In this paper,a long stroke moving secondary permanent magnet linear eddy current brake is proposed.Without exciting coils,the permanent magnet eddy current brake possesses the advantage of saving copper and better re...In this paper,a long stroke moving secondary permanent magnet linear eddy current brake is proposed.Without exciting coils,the permanent magnet eddy current brake possesses the advantage of saving copper and better reliability.The topology and operating principle are presented.The mathematical model was derived with the layer theory.The braking force characteristic was analyzed using the finite element method.The structural parameters of the long stroke moving secondary permanent magnet linear eddy current brake were studied by referring the design progress of the other types of eddy current brakes.Finally,a prototype of long stroke moving secondary permanent magnet linear eddy current brake was built and tested,and the experimental result verifies the correctness of the above analysis.展开更多
As a auxiliary brake, Permanent Magnet Retarder （PMR） generates lots of energy and has greater temperature-rise when PMR works, so that it has a direct impact on PMR work performance and even causes demagnetization ...As a auxiliary brake, Permanent Magnet Retarder （PMR） generates lots of energy and has greater temperature-rise when PMR works, so that it has a direct impact on PMR work performance and even causes demagnetization seriously. In order to analyze permanent magnet （PM） demagnetization in high-temperature in PMR, PMR mathematical model is established firstly, and the boundary conditions of finite element analysis are determined. Then the eddy current field distribution in the rotor is determined by solving eddy current demagnetization field, and PM dynamic permeance coefficient is obtained. Combined with PM demagnetization curve analysis, PMR permanent magnet demagnetization properties are analyzed. The analysis result is validated by the bench test. It shows that part of PM is demagnetized when PRM continues working for about 15 minutes, and the braking performance is declined. Finally, three PMR optimization design methods are proposed.展开更多
Rising concern in environmental issues on global scale has made energy saving in powered equipment a very important subject.In order to improve the energy efficiency and driving range of a motor hoist,a regenerative b...Rising concern in environmental issues on global scale has made energy saving in powered equipment a very important subject.In order to improve the energy efficiency and driving range of a motor hoist,a regenerative braking system is designed and discussed.The system takes a unique ultracapacitor-only approach to energy storage system.The bi-directional bride DC？DC converter which regulates current flow to and from the ultracapacitor operates in two modes：boost and buck,depending on the direction of the flow.In order to provide constant input and output current at the ultracapacitor,this system uses a double proportional-integral（PI） control strategy in regulating the duty cycle of PWM to the DC？DC converter.The permanent magnet synchronous motor（PWSM） drive system is also studied.The space vector pulse width modulation（SVPWM） technique,along with a two-closed-loop vector control model,is adopted after detailed analysis of PMSM characteristics.The overall model and control strategy for this regenerative braking system is ultimately built and simulated under the MATLAB and Simulink environment.A test platform is built to obtain experimental results.Analysis of the results reveals that more than half of the gravitational potential energy can be recovered by this system.Simulation and experimentation results testify the validity of the double PI control strategy for interface circuit of ultracapacitor and SVPWM strategy for PMSM.展开更多
基金This work was supported in part by the National Natural Science Foundation of China under Grant 51877051,the Research and Development Project of Scientific and Technological Achievements in Provincial Universities of Heilongjiang Education Department under Grant TSTAU-C2018014.
文摘In this paper,a long stroke moving secondary permanent magnet linear eddy current brake is proposed.Without exciting coils,the permanent magnet eddy current brake possesses the advantage of saving copper and better reliability.The topology and operating principle are presented.The mathematical model was derived with the layer theory.The braking force characteristic was analyzed using the finite element method.The structural parameters of the long stroke moving secondary permanent magnet linear eddy current brake were studied by referring the design progress of the other types of eddy current brakes.Finally,a prototype of long stroke moving secondary permanent magnet linear eddy current brake was built and tested,and the experimental result verifies the correctness of the above analysis.
文摘As a auxiliary brake, Permanent Magnet Retarder （PMR） generates lots of energy and has greater temperature-rise when PMR works, so that it has a direct impact on PMR work performance and even causes demagnetization seriously. In order to analyze permanent magnet （PM） demagnetization in high-temperature in PMR, PMR mathematical model is established firstly, and the boundary conditions of finite element analysis are determined. Then the eddy current field distribution in the rotor is determined by solving eddy current demagnetization field, and PM dynamic permeance coefficient is obtained. Combined with PM demagnetization curve analysis, PMR permanent magnet demagnetization properties are analyzed. The analysis result is validated by the bench test. It shows that part of PM is demagnetized when PRM continues working for about 15 minutes, and the braking performance is declined. Finally, three PMR optimization design methods are proposed.
基金supported by National Key Technology Research and Development Program of China (Grant No. 2007BAF10B00)
文摘Rising concern in environmental issues on global scale has made energy saving in powered equipment a very important subject.In order to improve the energy efficiency and driving range of a motor hoist,a regenerative braking system is designed and discussed.The system takes a unique ultracapacitor-only approach to energy storage system.The bi-directional bride DC？DC converter which regulates current flow to and from the ultracapacitor operates in two modes：boost and buck,depending on the direction of the flow.In order to provide constant input and output current at the ultracapacitor,this system uses a double proportional-integral（PI） control strategy in regulating the duty cycle of PWM to the DC？DC converter.The permanent magnet synchronous motor（PWSM） drive system is also studied.The space vector pulse width modulation（SVPWM） technique,along with a two-closed-loop vector control model,is adopted after detailed analysis of PMSM characteristics.The overall model and control strategy for this regenerative braking system is ultimately built and simulated under the MATLAB and Simulink environment.A test platform is built to obtain experimental results.Analysis of the results reveals that more than half of the gravitational potential energy can be recovered by this system.Simulation and experimentation results testify the validity of the double PI control strategy for interface circuit of ultracapacitor and SVPWM strategy for PMSM.
