High penetration of renewable energy sources(RESs)induces sharply-fluctuating feeder power,leading to volt-age deviation in active distribution systems.To prevent voltage violations,multi-terminal soft open points(M-s...High penetration of renewable energy sources(RESs)induces sharply-fluctuating feeder power,leading to volt-age deviation in active distribution systems.To prevent voltage violations,multi-terminal soft open points(M-sOPs)have been integrated into the distribution systems to enhance voltage con-trol flexibility.However,the M-SOP voltage control recalculated in real time cannot adapt to the rapid fluctuations of photovol-taic(PV)power,fundamentally limiting the voltage controllabili-ty of M-SOPs.To address this issue,a full-model-free adaptive graph deep deterministic policy gradient(FAG-DDPG)model is proposed for M-SOP voltage control.Specifically,the attention-based adaptive graph convolutional network(AGCN)is lever-aged to extract the complex correlation features of nodal infor-mation to improve the policy learning ability.Then,the AGCN-based surrogate model is trained to replace the power flow cal-culation to achieve model-free control.Furthermore,the deep deterministic policy gradient(DDPG)algorithm allows FAG-DDPG model to learn an optimal control strategy of M-SOP by continuous interactions with the AGCN-based surrogate model.Numerical tests have been performed on modified IEEE 33-node,123-node,and a real 76-node distribution systems,which demonstrate the effectiveness and generalization ability of the proposed FAG-DDPGmodel.展开更多
The Regional Integrated Energy System(RIES)has brought new modes of development,utilization,conversion,storage of energy.The introduction of Soft Open Point(SOP)and the application of Power to Gas(P2G)technology will ...The Regional Integrated Energy System(RIES)has brought new modes of development,utilization,conversion,storage of energy.The introduction of Soft Open Point(SOP)and the application of Power to Gas(P2G)technology will greatly deepen the coupling of the electricity-gas integrated energy system,improve the flexibility and safety of the operation of the power system,and bring a deal of benefits to the power system.On this background,an optimal dispatch model of RIES combined cold,heat,gas and electricity with SOP is proposed.Firstly,RIES architecture with SOP and P2G is designed and its mathematical model also is built.Secondly,on the basis of considering the optimal scheduling of combined cold,heat,gas and electricity,the optimal scheduling model for RIES was established.After that,the original model is transformed into a mixed-integer second-order cone programming model by using linearization and second-order cone relaxation techniques,and the CPLEX solver is invoked to solve the optimization problem.Finally,the modified IEEE 33-bus systemis used to analyze the benefits of SOP,P2G technology and lithium bromide absorption chillers in reducing systemnetwork loss and cost,as well as improving the system’s ability to absorb wind and solar and operating safety.展开更多
由于柔性多状态开关(soft normal open point,SNOP)复杂的控制策略及其弱馈特性,传统配电网故障定位方法难以适用于柔性互联配电网(flexible distribution network,FDN)。因此,文中提出一种利用电流正序分量波形相似性进行FDN故障区段...由于柔性多状态开关(soft normal open point,SNOP)复杂的控制策略及其弱馈特性,传统配电网故障定位方法难以适用于柔性互联配电网(flexible distribution network,FDN)。因此,文中提出一种利用电流正序分量波形相似性进行FDN故障区段定位的方法。首先,针对SNOP的典型控制策略,分析FDN的短路故障特征。其次,计算配电网中不同故障位置电流正序分量的Tanimoto系数,通过对比不同位置的电流正序分量波形相似性,构建FDN短路故障定位判据,并通过Teager能量算子(Teager energy operation,TEO)实现故障时刻的精确定位,利用智能配电终端(smart terminal unit,STU)传递信息。最后,通过建模仿真对所提方法进行分析验证,结果表明该方法能够对故障区段进行准确定位,不受故障位置、故障类型、过渡电阻、采样频率及通信延时等因素的影响,验证了该方法的可行性与有效性。展开更多
智能软开关(soft open point,SOP)能够提供实时潮流控制、故障快速自愈和馈线负载平衡,在配电网中得到了广泛应用。然而,电网电压暂降(grid voltage dips,GVD)是典型的大扰动工况,无法通过小信号方法分析配电网SOP在该工况下的稳定运行...智能软开关(soft open point,SOP)能够提供实时潮流控制、故障快速自愈和馈线负载平衡,在配电网中得到了广泛应用。然而,电网电压暂降(grid voltage dips,GVD)是典型的大扰动工况,无法通过小信号方法分析配电网SOP在该工况下的稳定运行机理。为此,采用混合势理论(mixed potential theory,MPT)研究了GVD工况下SOP的稳定性,并提出了增强SOP稳定性的参数优化策略和虚拟电容控制策略。首先,建立了SOP的非线性平均模型。在此基础上,利用MPT推导出SOP在GVD条件下的大信号稳定性判据(large signal stability criterion,LSSC)。此外,为了增强SOP系统的稳定性,基于LSSC提出了参数优化策略和构建虚拟电容的控制策略。最后,通过MATLAB/Simulink时域仿真验证了上述方法的有效性,即:1)基于LSSC可以有效地分析SOP在GVD下的稳定性;2)基于LSSC的系统参数优化策略和构建虚拟电容控制策略可以有效提高系统在大扰动条件下的稳定运行能力。展开更多
利用柔性多状态开关(soft open point,SOP)提升配电网的分布式能源(distributed generation,DG)消纳能力,提出了配电台区SOP的多目标优化控制策略。通过分析配电网SOP的接入模式,考虑其在分布式电源消纳与削峰填谷的作用,构建了分布式...利用柔性多状态开关(soft open point,SOP)提升配电网的分布式能源(distributed generation,DG)消纳能力,提出了配电台区SOP的多目标优化控制策略。通过分析配电网SOP的接入模式,考虑其在分布式电源消纳与削峰填谷的作用,构建了分布式能源日消纳量最大、控制成本最低和馈线日净负荷偏差最小的多目标模型。以改进的配电网算例进行仿真对比验证。结果表明:SOP接入有利于提升新能源消纳,并实现负载均衡。展开更多
基金This work was supported by the National Natural Science Foundation of China(No.72331008)GuangdongNaturalScienceFoundation(No.2023A1515010653)+1 种基金Environment and Conservation fund(No.ECF 49/2022)PolyU research project 1-YXBL and CDAH.
文摘High penetration of renewable energy sources(RESs)induces sharply-fluctuating feeder power,leading to volt-age deviation in active distribution systems.To prevent voltage violations,multi-terminal soft open points(M-sOPs)have been integrated into the distribution systems to enhance voltage con-trol flexibility.However,the M-SOP voltage control recalculated in real time cannot adapt to the rapid fluctuations of photovol-taic(PV)power,fundamentally limiting the voltage controllabili-ty of M-SOPs.To address this issue,a full-model-free adaptive graph deep deterministic policy gradient(FAG-DDPG)model is proposed for M-SOP voltage control.Specifically,the attention-based adaptive graph convolutional network(AGCN)is lever-aged to extract the complex correlation features of nodal infor-mation to improve the policy learning ability.Then,the AGCN-based surrogate model is trained to replace the power flow cal-culation to achieve model-free control.Furthermore,the deep deterministic policy gradient(DDPG)algorithm allows FAG-DDPG model to learn an optimal control strategy of M-SOP by continuous interactions with the AGCN-based surrogate model.Numerical tests have been performed on modified IEEE 33-node,123-node,and a real 76-node distribution systems,which demonstrate the effectiveness and generalization ability of the proposed FAG-DDPGmodel.
基金Project Supported by National Natural Science Foundation of China(51777193).
文摘The Regional Integrated Energy System(RIES)has brought new modes of development,utilization,conversion,storage of energy.The introduction of Soft Open Point(SOP)and the application of Power to Gas(P2G)technology will greatly deepen the coupling of the electricity-gas integrated energy system,improve the flexibility and safety of the operation of the power system,and bring a deal of benefits to the power system.On this background,an optimal dispatch model of RIES combined cold,heat,gas and electricity with SOP is proposed.Firstly,RIES architecture with SOP and P2G is designed and its mathematical model also is built.Secondly,on the basis of considering the optimal scheduling of combined cold,heat,gas and electricity,the optimal scheduling model for RIES was established.After that,the original model is transformed into a mixed-integer second-order cone programming model by using linearization and second-order cone relaxation techniques,and the CPLEX solver is invoked to solve the optimization problem.Finally,the modified IEEE 33-bus systemis used to analyze the benefits of SOP,P2G technology and lithium bromide absorption chillers in reducing systemnetwork loss and cost,as well as improving the system’s ability to absorb wind and solar and operating safety.
文摘由于柔性多状态开关(soft normal open point,SNOP)复杂的控制策略及其弱馈特性,传统配电网故障定位方法难以适用于柔性互联配电网(flexible distribution network,FDN)。因此,文中提出一种利用电流正序分量波形相似性进行FDN故障区段定位的方法。首先,针对SNOP的典型控制策略,分析FDN的短路故障特征。其次,计算配电网中不同故障位置电流正序分量的Tanimoto系数,通过对比不同位置的电流正序分量波形相似性,构建FDN短路故障定位判据,并通过Teager能量算子(Teager energy operation,TEO)实现故障时刻的精确定位,利用智能配电终端(smart terminal unit,STU)传递信息。最后,通过建模仿真对所提方法进行分析验证,结果表明该方法能够对故障区段进行准确定位,不受故障位置、故障类型、过渡电阻、采样频率及通信延时等因素的影响,验证了该方法的可行性与有效性。
文摘智能软开关(soft open point,SOP)能够提供实时潮流控制、故障快速自愈和馈线负载平衡,在配电网中得到了广泛应用。然而,电网电压暂降(grid voltage dips,GVD)是典型的大扰动工况,无法通过小信号方法分析配电网SOP在该工况下的稳定运行机理。为此,采用混合势理论(mixed potential theory,MPT)研究了GVD工况下SOP的稳定性,并提出了增强SOP稳定性的参数优化策略和虚拟电容控制策略。首先,建立了SOP的非线性平均模型。在此基础上,利用MPT推导出SOP在GVD条件下的大信号稳定性判据(large signal stability criterion,LSSC)。此外,为了增强SOP系统的稳定性,基于LSSC提出了参数优化策略和构建虚拟电容的控制策略。最后,通过MATLAB/Simulink时域仿真验证了上述方法的有效性,即:1)基于LSSC可以有效地分析SOP在GVD下的稳定性;2)基于LSSC的系统参数优化策略和构建虚拟电容控制策略可以有效提高系统在大扰动条件下的稳定运行能力。
文摘利用柔性多状态开关(soft open point,SOP)提升配电网的分布式能源(distributed generation,DG)消纳能力,提出了配电台区SOP的多目标优化控制策略。通过分析配电网SOP的接入模式,考虑其在分布式电源消纳与削峰填谷的作用,构建了分布式能源日消纳量最大、控制成本最低和馈线日净负荷偏差最小的多目标模型。以改进的配电网算例进行仿真对比验证。结果表明:SOP接入有利于提升新能源消纳,并实现负载均衡。
