Increasing penetration of distributed energy resources(DERs)introduced by different stakeholders,poses an immense challenge to power network operators.The traditional direct control of local DERs has the risk of viola...Increasing penetration of distributed energy resources(DERs)introduced by different stakeholders,poses an immense challenge to power network operators.The traditional direct control of local DERs has the risk of violating preferences and privacies of stakeholders.A promising solution for supplydemand coordination is to utilize a transactive energy(TE)based energy management method to indirectly coordinate the local DERs,which enables the distribution-level energy providers,consumers,and prosumers to trade energy with each other through a transactive energy system(TES)trading platform.This paper provides a comprehensive review of a TES and presents a detailed classification from different perspectives,including TES participants,structure,commodity,clearing method,and solution algorithm.The presented detailed component-scale classification can be used as a reference for future TES designs.Finally,two additional market tools,i.e.,penalty mechanism and loss allocation mechanism,are discussed as future focus areas,which can be seen as necessary complements to a TES for ensuring feasibility and fairness of energy trading.展开更多
The penetration of multi-carrier energy systems in distribution system gains more and more concerns.In this paper,a bi-level transactive energy trading framework is proposed to improve the energy scheduling and operat...The penetration of multi-carrier energy systems in distribution system gains more and more concerns.In this paper,a bi-level transactive energy trading framework is proposed to improve the energy scheduling and operation efficiency for multi-carrier energy systems which are modeled as energy hubs(EHs).In the upper level,each EH in the distribution system not only makes energy scheduling decisions considering supplies and demands of local energy,but also trades energy with each other to further maximize their social welfare.The associated trading payment among EHs is made in a fair manner by applying Nash bargaining theory.We solve the bargaining problem by decomposing it into two subproblems:operation cost minimization problem and payment bargaining problem.Then,based on the trading decision,the nodal equivalent loads of EHs are sent to the distribution system operator(DSO)without publishing trading details.By applying the second-order cone programming(SOCP),DSO reconfigures the network to reduce the transmission loss of the system in the lower level.The network reconfiguration and the trading behavior of EHs interact and iterate until the convergence.Numerical studies on modified IEEE 33-bus distribution system demonstrate the effectiveness of the proposed framework.展开更多
This paper presents a transactive demand response(TDR)scheme for a network of residential customers with generation assets that emphasizes interoperability within a transactive energy architecture.A complete laborator...This paper presents a transactive demand response(TDR)scheme for a network of residential customers with generation assets that emphasizes interoperability within a transactive energy architecture.A complete laboratory-based implementation provides the first(to our knowledge)realization of a comprehensive TDR use case that is fully compliant with the Institute of Electrical and Electronics Engineers(IEEE)2030.5 standard,which addresses interoperability within a cybersecure smart energy profile(SEP)context.Verification is provided by a full system integration with commercial hardware using Internet Protocol(IP)-based(local area network(LAN)and Wi-Fi)communication protocols and transport layer security(TLS)1.2 cryptographic protocol,and validation is provided by emulation using extensive residential smart meter data.The demand response(DR)scheme is designed to accommodate privacy concerns,allows customers to select their DR compliance level,and provides incentives to maximize their participation.The proposed TDR scheme addresses privacy through the implementation of the SEP 2.0 messaging protocol between a transactive agent(TA)and home energy management system(HEMS)agents.Customer response is handled by a multi-input multi-output(MIMO)fuzzy controller that manages negotiation between the customer agent and the TA.We take a multi-agent system approach to neighborhood coordination,with the TA servicing multiple residences on a common transformer,and use a reward mechanism to maximize customer engagement during the event-based optimization.Based on a set of smart meter data acquired over an extended time period,we engage in multiple TDR scenarios,and demonstrate with a fully-functional IEEE 2030.5-compliant implementation that our scheme can reduce network peak power consumption by 22%under realistic conditions.展开更多
The decreasing cost of solar photovoltaics(PVs)and battery storage systems is driving their adoption in the residential distribution system,where more consumers are becoming prosumers.Accompanying this trend is the po...The decreasing cost of solar photovoltaics(PVs)and battery storage systems is driving their adoption in the residential distribution system,where more consumers are becoming prosumers.Accompanying this trend is the potential roll-out of home energy management systems(HEMSs),which provide a means for prosumers to respond to externalities such as energy price,weather,and energy demands.However,the economic operation of prosumers can affect grid security,especially when energy prices are extremely low or high.Therefore,it is paramount to design a framework that can accommodate the interests of the key stakeholders in distribution systems—namely,the network operator,prosumer,and aggregator.In this paper,a novel transactive energy(TE)-based operational framework is proposed.Under this frame-work,aggregators interact with the distribution grid operator through a negotiation process to ensure network security,while at the lower level,prosumers submit their schedule to the aggregator through the HEMS.If network security is at risk,aggregators will send an additional price component representing the cost of security(CoS)to the prosumer to stimulate further response.The simulation results show that the proposed framework can effectively ensure the economic operation of aggregators and prosumers in distribution systems while maintaining grid security.展开更多
Healthcare for older adults with dementia is an important healthcare problem in Japan and in other developed countries. Importantly, healthcare workers in Japan are also getting older. In order to address solutions to...Healthcare for older adults with dementia is an important healthcare problem in Japan and in other developed countries. Importantly, healthcare workers in Japan are also getting older. In order to address solutions to this problem, using robots is being realized and is starting to assist healthcare and welfare practice needs. The aim of this study was to identify the characteristics of a transactive phenomenon in relationships among older adults with dementia, with nurses as intermediaries and with a cognitive skill-aid robot. Subjects were two institutionalized older adults who were diagnosed with dementia using Hasegawa’s Dementia Scale-Revised;a Kabochan (Nodding Kabochan) fixed with a remote-controlled speaker, Pechat (Kabochan with Pechat). Measurements of autonomic nervous activity were done using wearable electrocardiography attached to the subjects for four hours. Heart Rate Variability data were assessed at various frequency bands using a HRV software tool. In a continuously recorded data, interbeat (R-R) intervals were obtained for a 1-min segment using the maximum entropy method. In this study, the two major spectral components of HRV, the variances of the low-frequency (LF: 0.04 - 0.15 Hz) band and high-frequency (HF: 0.15 - 0.4 Hz) band, were calculated. Activities and behaviors of subjects transacting with Kabochan were observed by the expert nurses and video-recorded. Throughout the transaction period, observations were recorded of patients’ behavior, words uttered and over-all contents of the transactive conversation with the Kabochan or Kabochan with Pechat. Identified characteristics were transactive relationship phenomenon;changes in autonomic nervous system activity of persons with dementia are expressed as per one minute, linguistic response of elderly people, transactive relations among Kabochan, Kabochan with Pechat, and nurses as intermediaries. These were exhibited as Figures: Situation 1, A Sense of Fear, Situation 2, A Pleasant Sensation, and Situation 3, Misunderstanding and Confusion. It also showed that autonomic nervous system activity of persons with communication skills is actively changing in older adults with dementia. Conversation of adding Pechat to the Kabochan illustrated that nurses as intermediaries showed emotional conversations as established by effectively manipulating the Pechat. Also, it was revealed that if Kabochan with Pechat uttered words about patient’s personal information in a conversation, the patient felt a sense of fear. The researchers suggest that when developing future communication robot for elderly with dementia, it is necessary to consider, for an effective conversation, transactive relationships including nurses as intermediaries. The role functions of these intermediaries have been shown of high versatility, indicating that situations such as these can also be controlled by other healthcare providers such as by occupational therapists.展开更多
This paper reviews the state of the art of research and industry practice on demand response and the new methodology of transactive energy. Demand response programs incentivize consumers to align their demand with pow...This paper reviews the state of the art of research and industry practice on demand response and the new methodology of transactive energy. Demand response programs incentivize consumers to align their demand with power supply conditions, enhancing power system reliability and economic operation. The design of demand response programs, performance of pilot projects and programs, consumer behaviors, and barriers are discussed.Transactive energy is a variant and a generalized form of demand response in that it manages both the supply and demand sides. It is intended for a changing environment with an increasing number of distributed resources and intelligent devices. It utilizes the flexibility of various generation/load resources to maintain a dynamic balance of supply and demand. These distributed resources are controlled by their owners. However, the design of transaction mechanisms should align the individual behaviors with the interests of the entire system. Transactive energy features real-time, autonomous, and decentralized decision making.The transition from demand response to transactive energy is also discussed.展开更多
The increasing number of distributed energy resources connected to power systems raises operational challenges for the network operator, such as introducing grid congestion and voltage deviations in the distribution n...The increasing number of distributed energy resources connected to power systems raises operational challenges for the network operator, such as introducing grid congestion and voltage deviations in the distribution network level, as well as increasing balancing needs at the whole system level. Control and coordination of a large number of distributed energy assets requires innovative approaches. Transactive control has received much attention due to its decentralized decision-making and transparent characteristics. This paper introduces the concept and main features of transactive control, followed by a literature review and demonstration projects that apply to transactive control. Cases are then presented to illustrate the transactive control framework. At the end, discussions and research directions are presented, for applying transactive control to operating power systems, characterized by a high penetration of distributed energy resources.展开更多
Peer-to-peer(P2P)transactive energy trading offers a promising solution for facilitating the efficient and secure operation of a distribution system consisting of multiple prosumers.One critical but challenging task i...Peer-to-peer(P2P)transactive energy trading offers a promising solution for facilitating the efficient and secure operation of a distribution system consisting of multiple prosumers.One critical but challenging task is how to avoid system network constraints to be violated for the distribution system integrated with extensive P2P transactive energy trades.This paper proposes a security constrained decentralized P2P transactive energy trading framework,which allows direct energy trades among neighboring prosumers in the distribution system with enhanced system efficiency and security in which no conventional intermediary is required.The P2P transactive energy trading problem is formulated based on the Nash Bargaining theory and decomposed into two subproblems,i.e.,an OPF problem(P1)and a payment bargaining problem(P2).A distributed optimization method based on the alternating direction method of multiplier(ADMM)is adopted as a privacy-preserving solution to the formulated security constrained P2P transactive energy trading model with ensured accuracy.Extensive case studies based on a modified 33-bus distribution system are presented to validate the effectiveness of the proposed security constrained decentralized P2P transactive energy trading framework in terms of efficiency improvement,loss reduction,and voltage security enhancement.展开更多
Interest in transactive energy frameworks(TEFs)is proliferating due to the modern smart grid paradigm.This paper proposes a TEF,which applies auction-theory,incorporates a system of agents,and facilitates a transactiv...Interest in transactive energy frameworks(TEFs)is proliferating due to the modern smart grid paradigm.This paper proposes a TEF,which applies auction-theory,incorporates a system of agents,and facilitates a transactive energy market(TEM)through an auctioneer.Further,it also enables peer-to-peer(P2P)energy trading among the residential buildings in community microgrid for possible monetary benefits.In this framework,there are three agents,namely,auctioneer,participants,and utility.The auctioneer is a managing agent modeled using auction theory to determine day-ahead internal market-clearing price and quantity.The participants are autonomous and rational decision-makers;they aim to minimize their electricity bills through the demand response(DR)management.Two types of architectures,one with the third-party agent demonstrated using the MATLAB environment and the other with the virtual agent(without third-party)implemented using the blockchain environment are presented.The simulation results reflect significant monetary benefits to each market participant,improved community selfsufficiency,self-consumption,and reduced reliance on the utility grid.展开更多
Aggregating demand side flexibility is essential to complementing the inflexible and variable renewable energy supply in achieving low carbon energy systems.Sources of demand side flexibility,e.g.,dispatchable generat...Aggregating demand side flexibility is essential to complementing the inflexible and variable renewable energy supply in achieving low carbon energy systems.Sources of demand side flexibility,e.g.,dispatchable generators,storage,and flexible loads,can be structured in a form of microgrids and collectively provided to utility grids through transactive energy in local energy markets.This paper proposes a framework of local energy markets to manage this transactive energy and facilitate the flexibility provision.The distribution system operator aims to achieve local energy balance by scheduling the operation of multi-microgrids and determining the imbalance prices.Multiple microgrid traders aim to maximize profits for their prosumers through dispatching flexibility sources and participating in localised energy trading.The decision making and interactions between a distribution system operator and multiple microgrid traders are formulated as the Stackelberg game-theoretic problem.Case studies using the IEEE 69-bus distribution system demonstrate the effectiveness of the developed model in terms of facilitating local energy balance and reducing dependency on the utility grids.展开更多
In recent years,the advent of microgrids with numerous renewable energy sources has created some fundamental challenges in the control,coordination,and management of energy trading between microgrids and the power gri...In recent years,the advent of microgrids with numerous renewable energy sources has created some fundamental challenges in the control,coordination,and management of energy trading between microgrids and the power grid.To respond to these challenges,some techniques such as the transactive energy(TE)technology are proposed to control energy sharing.Therefore,this paper uses TE technology for energy exchange control among the microgrids,and applies three operation cases for analyzing the energy trading control of four and ten microgrids with the aim of minimizing the energy cost of each microgrid,respectively.In this regard,Monte Carlo simulation and fast forward selection(FFS)methods are respectively exerted for scenario generation and reduction in uncertainty modeling process.The first case is assumed that all microgrids can only receive energy from the network and do not have any connection with each other.In order to maximize the energy cost saving of each microgrid,the second case is proposed to provide a positive percentage of cost saving for microgrids.All microgrids can also trade energy with each other to get the most benefit by reducing the dependency on the main grid.The third case is similar to the second case,but its target is to indicate the scalability of the models based on the proposed TE technology by considering ten commercial microgrids.Finally,the simulation results indicate that microgrids can achieve the positive amount of cost saving in the second and third cases.In addition,the total energy cost of microgrids has been reduced in comparison with the first case.展开更多
With the rise of digital transactions, e-Wallets have become prime targets for fraudulent activity. Early detection of suspicious transactions is therefore crucial to protect users and maintain trust in these systems....With the rise of digital transactions, e-Wallets have become prime targets for fraudulent activity. Early detection of suspicious transactions is therefore crucial to protect users and maintain trust in these systems. This article proposes a mathematical model based on a Mixed Integer Program (MIP) to identify and block suspicious transactions. This mathematical approach is designed to analyze e-Wallet transactions in real time by combining integer and continuous decision variables, offering greater flexibility in modeling fraud detection constraints. It considers parameters such as transaction cost, geographical location, type of device used for the transaction, IP address and other potential fraud indicators. Assigning suspicion scores to each transaction enables the model to identify risks that become habitual behavior and mark them as suspicious. Tests carried out on 10,000 digital transactions show that using PMNE significantly improves the detection of fraudulent transactions by identifying the most critical anomalies in terms of accuracy, adaptability and operational efficiency. The model also offers greater accuracy, reducing the number of false positives and false negatives, enabling faster intervention to block truly suspicious transactions.展开更多
Cyber-Physical System (CPS) devices are increasing exponentially. Lacking confidentiality creates a vulnerable network. Thus, demanding the overall system with the latest and robust solutions for the defence mechanism...Cyber-Physical System (CPS) devices are increasing exponentially. Lacking confidentiality creates a vulnerable network. Thus, demanding the overall system with the latest and robust solutions for the defence mechanisms with low computation cost, increased integrity, and surveillance. The proposal of a mechanism that utilizes the features of authenticity measures using the Destination Sequence Distance Vector (DSDV) routing protocol which applies to the multi-WSN (Wireless Sensor Network) of IoT devices in CPS which is developed for the Device-to-Device (D2D) authentication developed from the local-chain and public chain respectively combined with the Software Defined Networking (SDN) control and monitoring system using switches and controllers that will route the packets through the network, identify any false nodes, take preventive measures against them and preventing them for any future problems. Next, the system is powered by Blockchain cryptographic features by utilizing the TrustChain features to create a private, secure, and temper-free ledger of the transactions performed inside the network. Results are achieved in the legitimate devices connecting to the network, transferring their packets to their destination under supervision, reporting whenever a false node is causing hurdles, and recording the transactions for temper-proof records. Evaluation results based on 1000+ transactions illustrate that the proposed mechanism not only outshines most aspects of Cyber-Physical systems but also consumes less computation power with a low latency of 0.1 seconds only.展开更多
In the contemporary era,characterized by the Internet and digitalization as fundamental features,the operation and application of digital currency have gradually developed into a comprehensive structural system.This s...In the contemporary era,characterized by the Internet and digitalization as fundamental features,the operation and application of digital currency have gradually developed into a comprehensive structural system.This system restores the essential characteristics of currency while providing auxiliary services related to the formation,circulation,storage,application,and promotion of digital currency.Compared to traditional currency management technologies,big data analysis technology,which is primarily embedded in digital currency systems,enables the rapid acquisition of information.This facilitates the identification of standard associations within currency data and provides technical support for the operational framework of digital currency.展开更多
Low data encryption efficiency and inadequate security are two issues with the current blockchain cross-chain transaction protection schemes.To address these issues,a blockchain cross-chain transaction protection sche...Low data encryption efficiency and inadequate security are two issues with the current blockchain cross-chain transaction protection schemes.To address these issues,a blockchain cross-chain transaction protection scheme based on Fully Homomorphic Encryption(FHE)is proposed.In the proposed scheme,the functional relationship is established by Box-Muller,Discrete Gaussian Distribution Function(DGDF)and Uniform Random Distribution Func-tion(URDF)are used to improve the security and efficiency of key generation.Subsequently,the data preprocessing function is introduced to perform cleaning,deduplication,and normalization operations on the transaction data of multi-key signature,and it is classified into interactive data and asset data,so as to perform different homomorphic operations in the FHE encryption stage.Ultimately,in the FHE encryption stage,homomorphic multiplication and homomorphic addition are used targeted for the interactive data and asset data,thereby reducing the computational complexity and enhancing the FHE encryption efficiency.The significance of the proposed scheme is proved by experimental results:Firstly,the multi-key generation function and its specific sampling method and transformation ensure the security and efficiency of key generation.Data preprocessing can also accelerate the FHE encryption process by eliminating invalid data and redundancy,so the FHE encryption efficiency is significantly improved.Secondly,the FHE encryption method based on discrete logarithm problem enhances the security of transaction data and can effectively resist multiple attacks.In addition,the preprocessed data also has good performance in capacity storage.The proposed scheme has significant impacts on key indicators such as encryption efficiency and security,it provides a new reference for blockchain cross-chain transaction protection technology and has an important impact on the security improvement of various cross-chain transaction data.展开更多
Local energy markets are emerging as a tool for coordinating generation, storage, and consumption of energyfrom distributed resources. In combination with automation, they promise to provide an effective energymanagem...Local energy markets are emerging as a tool for coordinating generation, storage, and consumption of energyfrom distributed resources. In combination with automation, they promise to provide an effective energymanagement framework that is fair and brings system-level savings. The cooperative–competitive natureof energy markets calls for multi-agent based automation with learning energy trading agents. However,depending on the dynamics of the agent–environment interaction, this approach may yield unintended behaviorof market participants. Thus, the design of market mechanisms suitable for reinforcement learning agentsmust take into account this interplay. This article introduces autonomous local energy exchange (ALEX) asan experimental framework that combines multi-agent learning and double auction mechanism. Participantsdetermine their internal price signals and make energy management decisions through market interactions,rather than relying on predetermined external price signals. The main contribution of this article is examinationof compatibility between specific market elements and independent learning agents. Effects of different marketproperties are evaluated through simulation experiments, and the results are used for determine a suitablemarket design. The results show that market truthfulness maintains demand-response functionality, while weakbudget balancing provides a strong reinforcement signal for the learning agents. The resulting agent behavioris compared with two baselines: net billing and time-of-use rates. The ALEX-based pricing is more responsiveto fluctuations in the community net load compared to the time-of-use. The more accurate accounting ofrenewable energy usage reduced bills by a median 38.8% compared to net billing, confirming the ability tobetter facilitate demand response.展开更多
Demand response transactions between electric consumers,load aggregators,and the distribution network manager based on the"combination of price and incentive"are feasible and efficient.However,the incentive ...Demand response transactions between electric consumers,load aggregators,and the distribution network manager based on the"combination of price and incentive"are feasible and efficient.However,the incentive payment of demand re-sponse is quantified based on private information,which gives the electric consumers and load aggregators the possibility of defrauding illegitimate interests by declaring false information.This paper proposes a method based on Vickrey-Clark-Groves(VCG)theory to prevent electric consumers and load aggregators from taking illegitimate interests through deceptive behaviors in the demand response transactions.Firstly,a demand response transaction framework with the price-and-incentive com-bined mode is established to illustrate the deceptive behaviors in the demand response transactions.Then,the idea for eradi-cating deceptive behaviors based on VCG theory is given,and a detailed VCG-based mathematical model is constructed follow-ing the demand response transaction framework.Further,the proofs of incentive compatibility,individual rationality,cost minimization,and budget balance of the proposed VCG-based method are given.Finally,a modified IEEE 33-node system and a modified IEEE 123-node system are used to illustrate and validate the proposed method.展开更多
Node synchronization is essential for the stability of the Bitcoin network. Critics have raised doubts about the ability of a new node to quickly and efficiently synchronize with the Bitcoin network and alleviate the ...Node synchronization is essential for the stability of the Bitcoin network. Critics have raised doubts about the ability of a new node to quickly and efficiently synchronize with the Bitcoin network and alleviate the storage pressure from existing full nodes to stockpile new data. Basic pruning and other techniques have been explored to address these concerns but have been insufficient to reduce node synchronization delay and effectively suppress the growth of synchronized data. In this study, we propose SnapshotPrune, a novel pruning and synchronization protocol that achieves fast node bootstrapping in the Bitcoin blockchain. Real Bitcoin historical data are leveraged to measure the synchronization time and monitor the network traffic during node bootstrapping. The protocol requires data downloads that are 99.70% less than Bitcoin Core, 81% less than CoinPrune, and 60% less than SnapshotSave, thereby saving 97.23% of download time. Findings show that the proposed design enhances the storage efficiency and reduces the node synchronization delay compared with existing techniques. We hypothesize that the efficiency of this protocol increases with the block height.展开更多
With the introduction of the“dual carbon”goal and the continuous promotion of low-carbon development,the integrated energy system(IES)has gradually become an effective way to save energy and reduce emissions.This st...With the introduction of the“dual carbon”goal and the continuous promotion of low-carbon development,the integrated energy system(IES)has gradually become an effective way to save energy and reduce emissions.This study proposes a low-carbon economic optimization scheduling model for an IES that considers carbon trading costs.With the goal of minimizing the total operating cost of the IES and considering the transferable and curtailable characteristics of the electric and thermal flexible loads,an optimal scheduling model of the IES that considers the cost of carbon trading and flexible loads on the user side was established.The role of flexible loads in improving the economy of an energy system was investigated using examples,and the rationality and effectiveness of the study were verified through a comparative analysis of different scenarios.The results showed that the total cost of the system in different scenarios was reduced by 18.04%,9.1%,3.35%,and 7.03%,respectively,whereas the total carbon emissions of the system were reduced by 65.28%,20.63%,3.85%,and 18.03%,respectively,when the carbon trading cost and demand-side flexible electric and thermal load responses were considered simultaneously.Flexible electrical and thermal loads did not have the same impact on the system performance.In the analyzed case,the total cost and carbon emissions of the system when only the flexible electrical load response was considered were lower than those when only the flexible thermal load response was taken into account.Photovoltaics have an excess of carbon trading credits and can profit from selling them,whereas other devices have an excess of carbon trading and need to buy carbon credits.展开更多
This paper draws on the experience of the eighth plenary meeting of the ISO/TC 321, Transaction assurance in e-commerce, held in Hangzhou of China in November 2023, and explores potential ways in which developing coun...This paper draws on the experience of the eighth plenary meeting of the ISO/TC 321, Transaction assurance in e-commerce, held in Hangzhou of China in November 2023, and explores potential ways in which developing countries in Africa can drive their development and contribute to global industrial progress by leveraging ISO/TC 321 standards. It provides practical recommendations for utilizing e-commerce standardization and related standards to stimulate economic growth and enhance business practices.展开更多
基金This work is supported by the National Research Foundation of Singapore,and the Energy Market Authority,under the Exploiting Distributed Generation(EDGE)Programme and administrated by the EDGE Programme Office(EDGE Programme Award No.EDGEGC2018-003).
文摘Increasing penetration of distributed energy resources(DERs)introduced by different stakeholders,poses an immense challenge to power network operators.The traditional direct control of local DERs has the risk of violating preferences and privacies of stakeholders.A promising solution for supplydemand coordination is to utilize a transactive energy(TE)based energy management method to indirectly coordinate the local DERs,which enables the distribution-level energy providers,consumers,and prosumers to trade energy with each other through a transactive energy system(TES)trading platform.This paper provides a comprehensive review of a TES and presents a detailed classification from different perspectives,including TES participants,structure,commodity,clearing method,and solution algorithm.The presented detailed component-scale classification can be used as a reference for future TES designs.Finally,two additional market tools,i.e.,penalty mechanism and loss allocation mechanism,are discussed as future focus areas,which can be seen as necessary complements to a TES for ensuring feasibility and fairness of energy trading.
文摘The penetration of multi-carrier energy systems in distribution system gains more and more concerns.In this paper,a bi-level transactive energy trading framework is proposed to improve the energy scheduling and operation efficiency for multi-carrier energy systems which are modeled as energy hubs(EHs).In the upper level,each EH in the distribution system not only makes energy scheduling decisions considering supplies and demands of local energy,but also trades energy with each other to further maximize their social welfare.The associated trading payment among EHs is made in a fair manner by applying Nash bargaining theory.We solve the bargaining problem by decomposing it into two subproblems:operation cost minimization problem and payment bargaining problem.Then,based on the trading decision,the nodal equivalent loads of EHs are sent to the distribution system operator(DSO)without publishing trading details.By applying the second-order cone programming(SOCP),DSO reconfigures the network to reduce the transmission loss of the system in the lower level.The network reconfiguration and the trading behavior of EHs interact and iterate until the convergence.Numerical studies on modified IEEE 33-bus distribution system demonstrate the effectiveness of the proposed framework.
基金Natural Sciences and Engineering Council of Canada(CRDPJ 477238-14)and Hydro Ottawa。
文摘This paper presents a transactive demand response(TDR)scheme for a network of residential customers with generation assets that emphasizes interoperability within a transactive energy architecture.A complete laboratory-based implementation provides the first(to our knowledge)realization of a comprehensive TDR use case that is fully compliant with the Institute of Electrical and Electronics Engineers(IEEE)2030.5 standard,which addresses interoperability within a cybersecure smart energy profile(SEP)context.Verification is provided by a full system integration with commercial hardware using Internet Protocol(IP)-based(local area network(LAN)and Wi-Fi)communication protocols and transport layer security(TLS)1.2 cryptographic protocol,and validation is provided by emulation using extensive residential smart meter data.The demand response(DR)scheme is designed to accommodate privacy concerns,allows customers to select their DR compliance level,and provides incentives to maximize their participation.The proposed TDR scheme addresses privacy through the implementation of the SEP 2.0 messaging protocol between a transactive agent(TA)and home energy management system(HEMS)agents.Customer response is handled by a multi-input multi-output(MIMO)fuzzy controller that manages negotiation between the customer agent and the TA.We take a multi-agent system approach to neighborhood coordination,with the TA servicing multiple residences on a common transformer,and use a reward mechanism to maximize customer engagement during the event-based optimization.Based on a set of smart meter data acquired over an extended time period,we engage in multiple TDR scenarios,and demonstrate with a fully-functional IEEE 2030.5-compliant implementation that our scheme can reduce network peak power consumption by 22%under realistic conditions.
基金supported by PVST project, funded under the Danish Energiteknologiske Udviklings-og Demonstrationsprogram (EUDP) programme (64017-0041)the State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources (LAPS21)
文摘The decreasing cost of solar photovoltaics(PVs)and battery storage systems is driving their adoption in the residential distribution system,where more consumers are becoming prosumers.Accompanying this trend is the potential roll-out of home energy management systems(HEMSs),which provide a means for prosumers to respond to externalities such as energy price,weather,and energy demands.However,the economic operation of prosumers can affect grid security,especially when energy prices are extremely low or high.Therefore,it is paramount to design a framework that can accommodate the interests of the key stakeholders in distribution systems—namely,the network operator,prosumer,and aggregator.In this paper,a novel transactive energy(TE)-based operational framework is proposed.Under this frame-work,aggregators interact with the distribution grid operator through a negotiation process to ensure network security,while at the lower level,prosumers submit their schedule to the aggregator through the HEMS.If network security is at risk,aggregators will send an additional price component representing the cost of security(CoS)to the prosumer to stimulate further response.The simulation results show that the proposed framework can effectively ensure the economic operation of aggregators and prosumers in distribution systems while maintaining grid security.
文摘Healthcare for older adults with dementia is an important healthcare problem in Japan and in other developed countries. Importantly, healthcare workers in Japan are also getting older. In order to address solutions to this problem, using robots is being realized and is starting to assist healthcare and welfare practice needs. The aim of this study was to identify the characteristics of a transactive phenomenon in relationships among older adults with dementia, with nurses as intermediaries and with a cognitive skill-aid robot. Subjects were two institutionalized older adults who were diagnosed with dementia using Hasegawa’s Dementia Scale-Revised;a Kabochan (Nodding Kabochan) fixed with a remote-controlled speaker, Pechat (Kabochan with Pechat). Measurements of autonomic nervous activity were done using wearable electrocardiography attached to the subjects for four hours. Heart Rate Variability data were assessed at various frequency bands using a HRV software tool. In a continuously recorded data, interbeat (R-R) intervals were obtained for a 1-min segment using the maximum entropy method. In this study, the two major spectral components of HRV, the variances of the low-frequency (LF: 0.04 - 0.15 Hz) band and high-frequency (HF: 0.15 - 0.4 Hz) band, were calculated. Activities and behaviors of subjects transacting with Kabochan were observed by the expert nurses and video-recorded. Throughout the transaction period, observations were recorded of patients’ behavior, words uttered and over-all contents of the transactive conversation with the Kabochan or Kabochan with Pechat. Identified characteristics were transactive relationship phenomenon;changes in autonomic nervous system activity of persons with dementia are expressed as per one minute, linguistic response of elderly people, transactive relations among Kabochan, Kabochan with Pechat, and nurses as intermediaries. These were exhibited as Figures: Situation 1, A Sense of Fear, Situation 2, A Pleasant Sensation, and Situation 3, Misunderstanding and Confusion. It also showed that autonomic nervous system activity of persons with communication skills is actively changing in older adults with dementia. Conversation of adding Pechat to the Kabochan illustrated that nurses as intermediaries showed emotional conversations as established by effectively manipulating the Pechat. Also, it was revealed that if Kabochan with Pechat uttered words about patient’s personal information in a conversation, the patient felt a sense of fear. The researchers suggest that when developing future communication robot for elderly with dementia, it is necessary to consider, for an effective conversation, transactive relationships including nurses as intermediaries. The role functions of these intermediaries have been shown of high versatility, indicating that situations such as these can also be controlled by other healthcare providers such as by occupational therapists.
基金This work is sponsored by Department of Commerce,State of Washington,and US Department of Energy,USA,through the Transactive Campus Energy Systems project,in collaboration with Pacific Northwest National Lab and University of Washington.
文摘This paper reviews the state of the art of research and industry practice on demand response and the new methodology of transactive energy. Demand response programs incentivize consumers to align their demand with power supply conditions, enhancing power system reliability and economic operation. The design of demand response programs, performance of pilot projects and programs, consumer behaviors, and barriers are discussed.Transactive energy is a variant and a generalized form of demand response in that it manages both the supply and demand sides. It is intended for a changing environment with an increasing number of distributed resources and intelligent devices. It utilizes the flexibility of various generation/load resources to maintain a dynamic balance of supply and demand. These distributed resources are controlled by their owners. However, the design of transaction mechanisms should align the individual behaviors with the interests of the entire system. Transactive energy features real-time, autonomous, and decentralized decision making.The transition from demand response to transactive energy is also discussed.
基金financed by the TNO Early Research Program on Energy Storage and Conversion(ERP ECS)through the SOSENS projectpartly supported by the Danish iPower project(http://www.ipowernet.dk/)funded by the Danish Agency for Research and Innovation(No.0603-00435B)
文摘The increasing number of distributed energy resources connected to power systems raises operational challenges for the network operator, such as introducing grid congestion and voltage deviations in the distribution network level, as well as increasing balancing needs at the whole system level. Control and coordination of a large number of distributed energy assets requires innovative approaches. Transactive control has received much attention due to its decentralized decision-making and transparent characteristics. This paper introduces the concept and main features of transactive control, followed by a literature review and demonstration projects that apply to transactive control. Cases are then presented to illustrate the transactive control framework. At the end, discussions and research directions are presented, for applying transactive control to operating power systems, characterized by a high penetration of distributed energy resources.
基金This work was supported in part by Shanghai Science and Technology Plan:Research and application for key technologies of public building virtual power plant based on distributed resource aggregation control,China(No.20dz1206200).
文摘Peer-to-peer(P2P)transactive energy trading offers a promising solution for facilitating the efficient and secure operation of a distribution system consisting of multiple prosumers.One critical but challenging task is how to avoid system network constraints to be violated for the distribution system integrated with extensive P2P transactive energy trades.This paper proposes a security constrained decentralized P2P transactive energy trading framework,which allows direct energy trades among neighboring prosumers in the distribution system with enhanced system efficiency and security in which no conventional intermediary is required.The P2P transactive energy trading problem is formulated based on the Nash Bargaining theory and decomposed into two subproblems,i.e.,an OPF problem(P1)and a payment bargaining problem(P2).A distributed optimization method based on the alternating direction method of multiplier(ADMM)is adopted as a privacy-preserving solution to the formulated security constrained P2P transactive energy trading model with ensured accuracy.Extensive case studies based on a modified 33-bus distribution system are presented to validate the effectiveness of the proposed security constrained decentralized P2P transactive energy trading framework in terms of efficiency improvement,loss reduction,and voltage security enhancement.
文摘Interest in transactive energy frameworks(TEFs)is proliferating due to the modern smart grid paradigm.This paper proposes a TEF,which applies auction-theory,incorporates a system of agents,and facilitates a transactive energy market(TEM)through an auctioneer.Further,it also enables peer-to-peer(P2P)energy trading among the residential buildings in community microgrid for possible monetary benefits.In this framework,there are three agents,namely,auctioneer,participants,and utility.The auctioneer is a managing agent modeled using auction theory to determine day-ahead internal market-clearing price and quantity.The participants are autonomous and rational decision-makers;they aim to minimize their electricity bills through the demand response(DR)management.Two types of architectures,one with the third-party agent demonstrated using the MATLAB environment and the other with the virtual agent(without third-party)implemented using the blockchain environment are presented.The simulation results reflect significant monetary benefits to each market participant,improved community selfsufficiency,self-consumption,and reduced reliance on the utility grid.
基金supported by National Key Research and Development Program of China (2019YFE0123600)National Natural Science Foundation of China (U2066211,52177124)+2 种基金in part by the Institute of Electrical Engineering,CAS (E155610101)the Youth Innovation Promotion Association of CAS (No.2019143)in part by the Ministry of Science and Technology of Chinese Taiwan under Grant MOST 109-2221-E007-020.
文摘Aggregating demand side flexibility is essential to complementing the inflexible and variable renewable energy supply in achieving low carbon energy systems.Sources of demand side flexibility,e.g.,dispatchable generators,storage,and flexible loads,can be structured in a form of microgrids and collectively provided to utility grids through transactive energy in local energy markets.This paper proposes a framework of local energy markets to manage this transactive energy and facilitate the flexibility provision.The distribution system operator aims to achieve local energy balance by scheduling the operation of multi-microgrids and determining the imbalance prices.Multiple microgrid traders aim to maximize profits for their prosumers through dispatching flexibility sources and participating in localised energy trading.The decision making and interactions between a distribution system operator and multiple microgrid traders are formulated as the Stackelberg game-theoretic problem.Case studies using the IEEE 69-bus distribution system demonstrate the effectiveness of the developed model in terms of facilitating local energy balance and reducing dependency on the utility grids.
基金supported by the Research Affairs Office of University of Tabriz,Tabriz,Iran
文摘In recent years,the advent of microgrids with numerous renewable energy sources has created some fundamental challenges in the control,coordination,and management of energy trading between microgrids and the power grid.To respond to these challenges,some techniques such as the transactive energy(TE)technology are proposed to control energy sharing.Therefore,this paper uses TE technology for energy exchange control among the microgrids,and applies three operation cases for analyzing the energy trading control of four and ten microgrids with the aim of minimizing the energy cost of each microgrid,respectively.In this regard,Monte Carlo simulation and fast forward selection(FFS)methods are respectively exerted for scenario generation and reduction in uncertainty modeling process.The first case is assumed that all microgrids can only receive energy from the network and do not have any connection with each other.In order to maximize the energy cost saving of each microgrid,the second case is proposed to provide a positive percentage of cost saving for microgrids.All microgrids can also trade energy with each other to get the most benefit by reducing the dependency on the main grid.The third case is similar to the second case,but its target is to indicate the scalability of the models based on the proposed TE technology by considering ten commercial microgrids.Finally,the simulation results indicate that microgrids can achieve the positive amount of cost saving in the second and third cases.In addition,the total energy cost of microgrids has been reduced in comparison with the first case.
文摘With the rise of digital transactions, e-Wallets have become prime targets for fraudulent activity. Early detection of suspicious transactions is therefore crucial to protect users and maintain trust in these systems. This article proposes a mathematical model based on a Mixed Integer Program (MIP) to identify and block suspicious transactions. This mathematical approach is designed to analyze e-Wallet transactions in real time by combining integer and continuous decision variables, offering greater flexibility in modeling fraud detection constraints. It considers parameters such as transaction cost, geographical location, type of device used for the transaction, IP address and other potential fraud indicators. Assigning suspicion scores to each transaction enables the model to identify risks that become habitual behavior and mark them as suspicious. Tests carried out on 10,000 digital transactions show that using PMNE significantly improves the detection of fraudulent transactions by identifying the most critical anomalies in terms of accuracy, adaptability and operational efficiency. The model also offers greater accuracy, reducing the number of false positives and false negatives, enabling faster intervention to block truly suspicious transactions.
基金funded by Ajman University,AU-Funded Research Grant 2023-IRG-ENIT-22.
文摘Cyber-Physical System (CPS) devices are increasing exponentially. Lacking confidentiality creates a vulnerable network. Thus, demanding the overall system with the latest and robust solutions for the defence mechanisms with low computation cost, increased integrity, and surveillance. The proposal of a mechanism that utilizes the features of authenticity measures using the Destination Sequence Distance Vector (DSDV) routing protocol which applies to the multi-WSN (Wireless Sensor Network) of IoT devices in CPS which is developed for the Device-to-Device (D2D) authentication developed from the local-chain and public chain respectively combined with the Software Defined Networking (SDN) control and monitoring system using switches and controllers that will route the packets through the network, identify any false nodes, take preventive measures against them and preventing them for any future problems. Next, the system is powered by Blockchain cryptographic features by utilizing the TrustChain features to create a private, secure, and temper-free ledger of the transactions performed inside the network. Results are achieved in the legitimate devices connecting to the network, transferring their packets to their destination under supervision, reporting whenever a false node is causing hurdles, and recording the transactions for temper-proof records. Evaluation results based on 1000+ transactions illustrate that the proposed mechanism not only outshines most aspects of Cyber-Physical systems but also consumes less computation power with a low latency of 0.1 seconds only.
文摘In the contemporary era,characterized by the Internet and digitalization as fundamental features,the operation and application of digital currency have gradually developed into a comprehensive structural system.This system restores the essential characteristics of currency while providing auxiliary services related to the formation,circulation,storage,application,and promotion of digital currency.Compared to traditional currency management technologies,big data analysis technology,which is primarily embedded in digital currency systems,enables the rapid acquisition of information.This facilitates the identification of standard associations within currency data and provides technical support for the operational framework of digital currency.
文摘Low data encryption efficiency and inadequate security are two issues with the current blockchain cross-chain transaction protection schemes.To address these issues,a blockchain cross-chain transaction protection scheme based on Fully Homomorphic Encryption(FHE)is proposed.In the proposed scheme,the functional relationship is established by Box-Muller,Discrete Gaussian Distribution Function(DGDF)and Uniform Random Distribution Func-tion(URDF)are used to improve the security and efficiency of key generation.Subsequently,the data preprocessing function is introduced to perform cleaning,deduplication,and normalization operations on the transaction data of multi-key signature,and it is classified into interactive data and asset data,so as to perform different homomorphic operations in the FHE encryption stage.Ultimately,in the FHE encryption stage,homomorphic multiplication and homomorphic addition are used targeted for the interactive data and asset data,thereby reducing the computational complexity and enhancing the FHE encryption efficiency.The significance of the proposed scheme is proved by experimental results:Firstly,the multi-key generation function and its specific sampling method and transformation ensure the security and efficiency of key generation.Data preprocessing can also accelerate the FHE encryption process by eliminating invalid data and redundancy,so the FHE encryption efficiency is significantly improved.Secondly,the FHE encryption method based on discrete logarithm problem enhances the security of transaction data and can effectively resist multiple attacks.In addition,the preprocessed data also has good performance in capacity storage.The proposed scheme has significant impacts on key indicators such as encryption efficiency and security,it provides a new reference for blockchain cross-chain transaction protection technology and has an important impact on the security improvement of various cross-chain transaction data.
文摘Local energy markets are emerging as a tool for coordinating generation, storage, and consumption of energyfrom distributed resources. In combination with automation, they promise to provide an effective energymanagement framework that is fair and brings system-level savings. The cooperative–competitive natureof energy markets calls for multi-agent based automation with learning energy trading agents. However,depending on the dynamics of the agent–environment interaction, this approach may yield unintended behaviorof market participants. Thus, the design of market mechanisms suitable for reinforcement learning agentsmust take into account this interplay. This article introduces autonomous local energy exchange (ALEX) asan experimental framework that combines multi-agent learning and double auction mechanism. Participantsdetermine their internal price signals and make energy management decisions through market interactions,rather than relying on predetermined external price signals. The main contribution of this article is examinationof compatibility between specific market elements and independent learning agents. Effects of different marketproperties are evaluated through simulation experiments, and the results are used for determine a suitablemarket design. The results show that market truthfulness maintains demand-response functionality, while weakbudget balancing provides a strong reinforcement signal for the learning agents. The resulting agent behavioris compared with two baselines: net billing and time-of-use rates. The ALEX-based pricing is more responsiveto fluctuations in the community net load compared to the time-of-use. The more accurate accounting ofrenewable energy usage reduced bills by a median 38.8% compared to net billing, confirming the ability tobetter facilitate demand response.
基金supported by the Fundamental Research Funds for the Central Universities(No.B230201048).
文摘Demand response transactions between electric consumers,load aggregators,and the distribution network manager based on the"combination of price and incentive"are feasible and efficient.However,the incentive payment of demand re-sponse is quantified based on private information,which gives the electric consumers and load aggregators the possibility of defrauding illegitimate interests by declaring false information.This paper proposes a method based on Vickrey-Clark-Groves(VCG)theory to prevent electric consumers and load aggregators from taking illegitimate interests through deceptive behaviors in the demand response transactions.Firstly,a demand response transaction framework with the price-and-incentive com-bined mode is established to illustrate the deceptive behaviors in the demand response transactions.Then,the idea for eradi-cating deceptive behaviors based on VCG theory is given,and a detailed VCG-based mathematical model is constructed follow-ing the demand response transaction framework.Further,the proofs of incentive compatibility,individual rationality,cost minimization,and budget balance of the proposed VCG-based method are given.Finally,a modified IEEE 33-node system and a modified IEEE 123-node system are used to illustrate and validate the proposed method.
基金supported by the National Key Project of China(No.2020YFB1005700)the Natural Science Foundation of Shandong Province(No.ZR2021MF086)+3 种基金the National Key Research and Development Program of China(No.2021YFA1000600)the National Natural Science Foundation of China(Nos.62132018 and 62172117)the National Key Research and Development Program,the Young Scientist Scheme(No.2022YFB3102400)the National Key Research and Development Program of Guangdong Province(No.2020B0101090002).
文摘Node synchronization is essential for the stability of the Bitcoin network. Critics have raised doubts about the ability of a new node to quickly and efficiently synchronize with the Bitcoin network and alleviate the storage pressure from existing full nodes to stockpile new data. Basic pruning and other techniques have been explored to address these concerns but have been insufficient to reduce node synchronization delay and effectively suppress the growth of synchronized data. In this study, we propose SnapshotPrune, a novel pruning and synchronization protocol that achieves fast node bootstrapping in the Bitcoin blockchain. Real Bitcoin historical data are leveraged to measure the synchronization time and monitor the network traffic during node bootstrapping. The protocol requires data downloads that are 99.70% less than Bitcoin Core, 81% less than CoinPrune, and 60% less than SnapshotSave, thereby saving 97.23% of download time. Findings show that the proposed design enhances the storage efficiency and reduces the node synchronization delay compared with existing techniques. We hypothesize that the efficiency of this protocol increases with the block height.
基金supported by State Grid Shanxi Electric Power Company Science and Technology Project“Research on key technologies of carbon tracking and carbon evaluation for new power system”(Grant:520530230005)。
文摘With the introduction of the“dual carbon”goal and the continuous promotion of low-carbon development,the integrated energy system(IES)has gradually become an effective way to save energy and reduce emissions.This study proposes a low-carbon economic optimization scheduling model for an IES that considers carbon trading costs.With the goal of minimizing the total operating cost of the IES and considering the transferable and curtailable characteristics of the electric and thermal flexible loads,an optimal scheduling model of the IES that considers the cost of carbon trading and flexible loads on the user side was established.The role of flexible loads in improving the economy of an energy system was investigated using examples,and the rationality and effectiveness of the study were verified through a comparative analysis of different scenarios.The results showed that the total cost of the system in different scenarios was reduced by 18.04%,9.1%,3.35%,and 7.03%,respectively,whereas the total carbon emissions of the system were reduced by 65.28%,20.63%,3.85%,and 18.03%,respectively,when the carbon trading cost and demand-side flexible electric and thermal load responses were considered simultaneously.Flexible electrical and thermal loads did not have the same impact on the system performance.In the analyzed case,the total cost and carbon emissions of the system when only the flexible electrical load response was considered were lower than those when only the flexible thermal load response was taken into account.Photovoltaics have an excess of carbon trading credits and can profit from selling them,whereas other devices have an excess of carbon trading and need to buy carbon credits.
文摘This paper draws on the experience of the eighth plenary meeting of the ISO/TC 321, Transaction assurance in e-commerce, held in Hangzhou of China in November 2023, and explores potential ways in which developing countries in Africa can drive their development and contribute to global industrial progress by leveraging ISO/TC 321 standards. It provides practical recommendations for utilizing e-commerce standardization and related standards to stimulate economic growth and enhance business practices.
