In order to improve the characteristics of a conventional moving coil permanent magnet linear motor （MCPMLM）, such as weak points on export force, response time, response speed, we studied a permanent magnet （PM） ...In order to improve the characteristics of a conventional moving coil permanent magnet linear motor （MCPMLM）, such as weak points on export force, response time, response speed, we studied a permanent magnet （PM） structure that is a key component of MCPMLM. Different magnetization techniques of single PM and differ- ent array structures of multiple PMs are compared, and a new MCPMLM magnetized along the external field force lines wing eight pieces of a tegular Halbach magnet array with air gaps is proposed as well. The analysis on magnetic field and experimental results of MCPMLM demonstrates that the force between the coil and the PM increases by more than 40%. The simulation frequeney is close to 350 Hz at -3 dB , and the response time is O. 005 s. In addition, the experiment frequency reaches 300 Hz at -3 dB and the response time is 0. 004 s, which agrees well with the simulation results. It means that the developed MCPMLM enjoys advantages in high frequency and rapid response, and can satisfy the requirements of a high speed electro-hydraulic proportional valve.展开更多
Hydrogen-powered electric aircraft have attracted significant interests aiming to achieve decarbonization targets.Onboard DC electric networks are facing great challenges in DC fault protection requirements.Vacuum int...Hydrogen-powered electric aircraft have attracted significant interests aiming to achieve decarbonization targets.Onboard DC electric networks are facing great challenges in DC fault protection requirements.Vacuum interrupters are widely used in low voltage and medium voltage power systems due to being environmentally friendly with low maintenance.In this paper a moving coil actuator with compensation coils for a vacuum interrupter,as part of a hybrid direct current circuit breaker,is designed and experimentally tested.Compensation coils are used to improve operating speed compared with original moving coil actuator.Comparisons between four possible connections of compensation coils and original moving coil actuator are carried out.Experimental results show comparisons between different connections of actuator coils in terms of opening time and coil current with a range of pre-charged capacitor voltages.Dynamic performance of each actuator connection is also compared.The actuator with compensation coils is shown to have a higher current rising rate and achieve faster opening speed,which is a critical requirement for electric aircraft network protection.The parallel connection actuator achieves the highest opening speed within 3.5 ms with capacitor voltage of 50 V.展开更多
DC circuit breakers are major enabling components for multi-terminal HVDC systems.Their key design targets are operating speed and efficiency.This paper proposes a novel moving coil actuator using a compensation coil ...DC circuit breakers are major enabling components for multi-terminal HVDC systems.Their key design targets are operating speed and efficiency.This paper proposes a novel moving coil actuator using a compensation coil topology to operate mechanical circuit breakers.This topology aims to significantly improve the magnetic field saturation and reduce the system inductance,so that the operating speed is increased.Four possible connection methods for the compensation coils are proposed and analyzed using finite element modeling,ensuing simulation results are compared and discussed.The operating speed of the moving coil actuator with compensation coils is significantly improved compared with the original moving coil actuator.The moving coil actuator with compensation coils can open a distance of 5 mm within 2.8 ms and the peak efficiency is 47%.展开更多
基金supported by The National High Technology Research and Development of China (863 Programme) under Grant No. 2006AA09Z226
文摘In order to improve the characteristics of a conventional moving coil permanent magnet linear motor （MCPMLM）, such as weak points on export force, response time, response speed, we studied a permanent magnet （PM） structure that is a key component of MCPMLM. Different magnetization techniques of single PM and differ- ent array structures of multiple PMs are compared, and a new MCPMLM magnetized along the external field force lines wing eight pieces of a tegular Halbach magnet array with air gaps is proposed as well. The analysis on magnetic field and experimental results of MCPMLM demonstrates that the force between the coil and the PM increases by more than 40%. The simulation frequeney is close to 350 Hz at -3 dB , and the response time is O. 005 s. In addition, the experiment frequency reaches 300 Hz at -3 dB and the response time is 0. 004 s, which agrees well with the simulation results. It means that the developed MCPMLM enjoys advantages in high frequency and rapid response, and can satisfy the requirements of a high speed electro-hydraulic proportional valve.
基金supported in part by the UK Aerospace Technology Institute under contract 103136-Zero Emissions for Sustainable Transport 1(ZEST 1).
文摘Hydrogen-powered electric aircraft have attracted significant interests aiming to achieve decarbonization targets.Onboard DC electric networks are facing great challenges in DC fault protection requirements.Vacuum interrupters are widely used in low voltage and medium voltage power systems due to being environmentally friendly with low maintenance.In this paper a moving coil actuator with compensation coils for a vacuum interrupter,as part of a hybrid direct current circuit breaker,is designed and experimentally tested.Compensation coils are used to improve operating speed compared with original moving coil actuator.Comparisons between four possible connections of compensation coils and original moving coil actuator are carried out.Experimental results show comparisons between different connections of actuator coils in terms of opening time and coil current with a range of pre-charged capacitor voltages.Dynamic performance of each actuator connection is also compared.The actuator with compensation coils is shown to have a higher current rising rate and achieve faster opening speed,which is a critical requirement for electric aircraft network protection.The parallel connection actuator achieves the highest opening speed within 3.5 ms with capacitor voltage of 50 V.
文摘DC circuit breakers are major enabling components for multi-terminal HVDC systems.Their key design targets are operating speed and efficiency.This paper proposes a novel moving coil actuator using a compensation coil topology to operate mechanical circuit breakers.This topology aims to significantly improve the magnetic field saturation and reduce the system inductance,so that the operating speed is increased.Four possible connection methods for the compensation coils are proposed and analyzed using finite element modeling,ensuing simulation results are compared and discussed.The operating speed of the moving coil actuator with compensation coils is significantly improved compared with the original moving coil actuator.The moving coil actuator with compensation coils can open a distance of 5 mm within 2.8 ms and the peak efficiency is 47%.
