针对三电平变换器通常在轻载工作状态下滞后桥臂开关管实现零电压开关(zero voltage switching,ZVS)较为困难,整流二极管两端也存在电压尖峰和振荡的问题,在常规的三电平变换器主电路拓扑中加入辅助变压器,使其在宽负载范围内实现软开...针对三电平变换器通常在轻载工作状态下滞后桥臂开关管实现零电压开关(zero voltage switching,ZVS)较为困难,整流二极管两端也存在电压尖峰和振荡的问题,在常规的三电平变换器主电路拓扑中加入辅助变压器,使其在宽负载范围内实现软开关。对三电平变换器的工作原理及宽负载范围内实现ZVS的可行性进行详细分析。该新型拓扑是通过一台24V/10A,80kHz的实验样机进行了验证,实验结果表明变换器能够在宽负载范围内实现ZVS,并具有良好的性能。展开更多
The full-bridge converters usually use transformer leakage inductance and parallel resonant capacitors to achieve smooth current commutation and soft switching functions,which can easily cause problems such as energy ...The full-bridge converters usually use transformer leakage inductance and parallel resonant capacitors to achieve smooth current commutation and soft switching functions,which can easily cause problems such as energy leakage and significant duty cycle loss.This paper designs a novel full-bridge zero-current(FB-ZCS)converter with series resonant capacitors and proposes a frequency and phase-shift synthesis modulation(FPSSM)control strategy based on this topology.Compared with the traditional parallel resonant capacitor circuit,the passive components used are significantly reduced,the structure is simple,and there is only a slight energy loss.By controlling the charging time of the capacitor,it can be achieved without additional switches or auxiliary circuits.The automatic control of capacitor energy based on input current addresses the low efficiency of the traditional control strategies.This paper introduces its principle in detail and verifies it through simulation.Finally,an experimental prototype was built further to demonstrate the feasibility of the theory through experiments.The module can be applied to a photovoltaic DC collection system using input parallel output series(IPOS)cascade to provide a new topology for large-scale,long-distance DC transmission.展开更多
针对电动汽车充电电源额外热量产生影响电池使用寿命的问题,提出一种无电解电容隔离式单级双向AC/DC变换器。该变换器能有效阻止低频功率纹波注入电池单元,减少了额外热量的产生;同时电解电容的消除也大大提高了系统的可靠性。控制策略...针对电动汽车充电电源额外热量产生影响电池使用寿命的问题,提出一种无电解电容隔离式单级双向AC/DC变换器。该变换器能有效阻止低频功率纹波注入电池单元,减少了额外热量的产生;同时电解电容的消除也大大提高了系统的可靠性。控制策略方面,提出的一种四相控制器,不仅能使所有开关管实现零电压开关(Zero Voltage Switch,ZVS),并在导通损耗进行了性能优化。最后,通过PSIM仿真软件和实验样机,验证了理论分析的正确性和可行性。展开更多
文中提出一种新型单级式隔离AC-DC变换器及控制方案。所提结构在不改变图腾柱无桥功率因数校正(totem pole bridge-free power factor correction,TP-PFC)和双向全桥(dual active bridge,DAB)两级式AC-DC变换器特性的前提下,将TP-PFC高...文中提出一种新型单级式隔离AC-DC变换器及控制方案。所提结构在不改变图腾柱无桥功率因数校正(totem pole bridge-free power factor correction,TP-PFC)和双向全桥(dual active bridge,DAB)两级式AC-DC变换器特性的前提下,将TP-PFC高频桥臂和DAB原边侧第一个桥臂进行开关复用,减小了开关器件数目。同时,相较于TP-PFC和DAB两级式AC-DC变换器,取消了直流母线电解电容并且抑制了交流电感电流尖峰。利用其拓扑特点及所提出的控制方案,实现了拓扑开关器件的全范围软开关。首先详细分析所提拓扑结构的工作特性,包括工作模态、拓扑优点、功率特性及软开关特性;其次基于对拓扑的分析,提出控制简单的控制策略;最后,对所提拓扑结构及控制方案进行实验验证。展开更多
A novel DC traction power supply system suitable for energy feeding and de-icing is proposed in this paper for an urban rail transit catenary on the basis of the full bridge submodule (FBSM) modular multilevel convert...A novel DC traction power supply system suitable for energy feeding and de-icing is proposed in this paper for an urban rail transit catenary on the basis of the full bridge submodule (FBSM) modular multilevel converter (MMC). The FBSM-MMC is a novel type of voltage source converter (VSC) and can directly control the output DC voltage and conduct bipolar currents, thus flexibly controlling the power flow of the urban rail transit catenary. The proposed topology can overcome the inherent disadvantages of the output voltage drop in the diode rectifier units, increase the power supply distance and reduce the number of traction substations. The flexible DC technology can coordinate multiple FBSM-MMCs in a wide area and jointly complete the bidirectional control of catenary power flow during the operation of the electric locomotive, so as to realize the local consumption and optimal utilization of the recovered braking energy of the train. In addition, the FBSM-MMCs can also adjust the output current when the locomotive is out of service to prevent the catenary from icing in winter. The working modes of the proposed topology are illustrated in detail and the control strategy is specially designed for normal locomotive operations and catenary de-icing. Simulation cases conducted by PSCAD/EMTDC validate the proposed topology and its control strategy.展开更多
文摘针对三电平变换器通常在轻载工作状态下滞后桥臂开关管实现零电压开关(zero voltage switching,ZVS)较为困难,整流二极管两端也存在电压尖峰和振荡的问题,在常规的三电平变换器主电路拓扑中加入辅助变压器,使其在宽负载范围内实现软开关。对三电平变换器的工作原理及宽负载范围内实现ZVS的可行性进行详细分析。该新型拓扑是通过一台24V/10A,80kHz的实验样机进行了验证,实验结果表明变换器能够在宽负载范围内实现ZVS,并具有良好的性能。
基金This work was supported by the Key R&D Program of Tianjin(No.20YFYSGX00060).
文摘The full-bridge converters usually use transformer leakage inductance and parallel resonant capacitors to achieve smooth current commutation and soft switching functions,which can easily cause problems such as energy leakage and significant duty cycle loss.This paper designs a novel full-bridge zero-current(FB-ZCS)converter with series resonant capacitors and proposes a frequency and phase-shift synthesis modulation(FPSSM)control strategy based on this topology.Compared with the traditional parallel resonant capacitor circuit,the passive components used are significantly reduced,the structure is simple,and there is only a slight energy loss.By controlling the charging time of the capacitor,it can be achieved without additional switches or auxiliary circuits.The automatic control of capacitor energy based on input current addresses the low efficiency of the traditional control strategies.This paper introduces its principle in detail and verifies it through simulation.Finally,an experimental prototype was built further to demonstrate the feasibility of the theory through experiments.The module can be applied to a photovoltaic DC collection system using input parallel output series(IPOS)cascade to provide a new topology for large-scale,long-distance DC transmission.
文摘针对电动汽车充电电源额外热量产生影响电池使用寿命的问题,提出一种无电解电容隔离式单级双向AC/DC变换器。该变换器能有效阻止低频功率纹波注入电池单元,减少了额外热量的产生;同时电解电容的消除也大大提高了系统的可靠性。控制策略方面,提出的一种四相控制器,不仅能使所有开关管实现零电压开关(Zero Voltage Switch,ZVS),并在导通损耗进行了性能优化。最后,通过PSIM仿真软件和实验样机,验证了理论分析的正确性和可行性。
文摘文中提出一种新型单级式隔离AC-DC变换器及控制方案。所提结构在不改变图腾柱无桥功率因数校正(totem pole bridge-free power factor correction,TP-PFC)和双向全桥(dual active bridge,DAB)两级式AC-DC变换器特性的前提下,将TP-PFC高频桥臂和DAB原边侧第一个桥臂进行开关复用,减小了开关器件数目。同时,相较于TP-PFC和DAB两级式AC-DC变换器,取消了直流母线电解电容并且抑制了交流电感电流尖峰。利用其拓扑特点及所提出的控制方案,实现了拓扑开关器件的全范围软开关。首先详细分析所提拓扑结构的工作特性,包括工作模态、拓扑优点、功率特性及软开关特性;其次基于对拓扑的分析,提出控制简单的控制策略;最后,对所提拓扑结构及控制方案进行实验验证。
基金supported in part by National Key Research and Development Program of China(2017YFB1200801)Continuous Co-phase Traction Power System based on Static Power Converter(20192001148).
文摘A novel DC traction power supply system suitable for energy feeding and de-icing is proposed in this paper for an urban rail transit catenary on the basis of the full bridge submodule (FBSM) modular multilevel converter (MMC). The FBSM-MMC is a novel type of voltage source converter (VSC) and can directly control the output DC voltage and conduct bipolar currents, thus flexibly controlling the power flow of the urban rail transit catenary. The proposed topology can overcome the inherent disadvantages of the output voltage drop in the diode rectifier units, increase the power supply distance and reduce the number of traction substations. The flexible DC technology can coordinate multiple FBSM-MMCs in a wide area and jointly complete the bidirectional control of catenary power flow during the operation of the electric locomotive, so as to realize the local consumption and optimal utilization of the recovered braking energy of the train. In addition, the FBSM-MMCs can also adjust the output current when the locomotive is out of service to prevent the catenary from icing in winter. The working modes of the proposed topology are illustrated in detail and the control strategy is specially designed for normal locomotive operations and catenary de-icing. Simulation cases conducted by PSCAD/EMTDC validate the proposed topology and its control strategy.
