The Vienna rectifier with unbalanced input voltage and load transient is analyzed.A nonlinear control strategy for Vienna rectifier under unbalanced input is proposed.From the view of positive and negative sequence co...The Vienna rectifier with unbalanced input voltage and load transient is analyzed.A nonlinear control strategy for Vienna rectifier under unbalanced input is proposed.From the view of positive and negative sequence components,the proposed nonlinear control strategy suppresses the twice frequency ripple and guarantees the dynamic response characteristic at the same time.Thanks to the proposed nonlinear control strategy,the DC bus capacitor can be reduced a lot since the voltage ripple and drop can be suppressed.A 10 kW Vienna rectifier is built to verify the proposed control strategy.After applying the proposed nonlinear control strategy,the voltage ripple is only7 V and decreases over 75%over the traditional PI control when the unbalanced degree is 20%.The voltage drop can be reduced about 80%than former control strategy which is helpful to reduce the DC bus capacitor and achieve higher power density.The volume of the capacitor can be reduced by 83.3%with the new control method.展开更多
In this paper, a voltage oriented control strategy for three-level PWM rectifier based on Sliding Mode Control (SMC) is introduced in order to obtain fast and accurate response of dc-bus voltage. To verify the validit...In this paper, a voltage oriented control strategy for three-level PWM rectifier based on Sliding Mode Control (SMC) is introduced in order to obtain fast and accurate response of dc-bus voltage. To verify the validity of the analysis and the feasibility of the proposed control method a set of simulation tests have been conducted using Matlab/Simulink. The simulation results show that compared to the conventional PI controller, the SMC can reduce drastically the three-level rectifier’s voltage fluctuation and improve the dynamic response of dc-bus significantly.展开更多
Due to attractive features,including high efficiency,low device stress,and ability to boost voltage,a Vienna rectifier is commonly employed as a battery charger in an electric vehicle(EV).However,the 6k±1 harmoni...Due to attractive features,including high efficiency,low device stress,and ability to boost voltage,a Vienna rectifier is commonly employed as a battery charger in an electric vehicle(EV).However,the 6k±1 harmonics in the acside current of the Vienna rectifier deteriorate theTHDof the ac current,thus lowering the power factor.Therefore,the current closed-loop for suppressing 6k±1 harmonics is essential tomeet the desired total harmonic distortion(THD).Fast repetitive control(FRC)is generally adopted;however,the deviation of power grid frequency causes delay link in the six frequency fast repetitive control to become non-integer and the tracking performance to deteriorate.This paper presents the detailed parameter design and calculation of fractional order fast repetitive controller(FOFRC)for the non-integer delay link.The finite polynomial approximates the non-integer delay link through the Lagrange interpolation method.By comparing the frequency characteristics of traditional repetitive control,the effectiveness of the FOFRC strategy is verified.Finally,simulation and experiment validate the steadystate performance and harmonics suppression ability of FOFRC.展开更多
针对由电网不对称引起的Vienna整流器有功功率波动和电流不对称问题,介绍了有功功率波动的抑制控制APFSC(active power fluctuation suppression control )和对称的正序电流控制SPSCC(symmetric positivesequence current control )。...针对由电网不对称引起的Vienna整流器有功功率波动和电流不对称问题,介绍了有功功率波动的抑制控制APFSC(active power fluctuation suppression control )和对称的正序电流控制SPSCC(symmetric positivesequence current control )。由于受到功率器件的电流限制,采用APFSC会导致Vienna整流器运行的最大有功功率降低;采用SPSCC可以扩展Vienna整流器运行的最大有功功率,但有功功率波动较大。基于此,提出1种改进的功率控制IPC(improved power control )策略。当Vienna整流器处理功率较小时,以保持有功功率无波动为首要目标,此时IPC与APFSC的效果一致,对比SPSCC,IPC可有效抑制有功功率的波动;当Vienna整流器处理功率较大时,以满足功率需求为首要目标,但尽可能地减小有功功率波动,此时APFSC无法满足功率需求,但IPC可以满足有功功率需求,且在满足功率需求的前提下,对比SPSCC,IPC下有功功率的波动更小。最后通过实验验证了控制方法的优越性。展开更多
基金supported in part by the National Natural Science Foundation of China (Nos. 51777093 ,51722702)
文摘The Vienna rectifier with unbalanced input voltage and load transient is analyzed.A nonlinear control strategy for Vienna rectifier under unbalanced input is proposed.From the view of positive and negative sequence components,the proposed nonlinear control strategy suppresses the twice frequency ripple and guarantees the dynamic response characteristic at the same time.Thanks to the proposed nonlinear control strategy,the DC bus capacitor can be reduced a lot since the voltage ripple and drop can be suppressed.A 10 kW Vienna rectifier is built to verify the proposed control strategy.After applying the proposed nonlinear control strategy,the voltage ripple is only7 V and decreases over 75%over the traditional PI control when the unbalanced degree is 20%.The voltage drop can be reduced about 80%than former control strategy which is helpful to reduce the DC bus capacitor and achieve higher power density.The volume of the capacitor can be reduced by 83.3%with the new control method.
文摘In this paper, a voltage oriented control strategy for three-level PWM rectifier based on Sliding Mode Control (SMC) is introduced in order to obtain fast and accurate response of dc-bus voltage. To verify the validity of the analysis and the feasibility of the proposed control method a set of simulation tests have been conducted using Matlab/Simulink. The simulation results show that compared to the conventional PI controller, the SMC can reduce drastically the three-level rectifier’s voltage fluctuation and improve the dynamic response of dc-bus significantly.
基金funded by the Xi’an Science and Technology Plan Project,Grant No.2020KJRC001the Xi’an Science and Technology Plan Project,Grant No.21XJZZ0003。
文摘Due to attractive features,including high efficiency,low device stress,and ability to boost voltage,a Vienna rectifier is commonly employed as a battery charger in an electric vehicle(EV).However,the 6k±1 harmonics in the acside current of the Vienna rectifier deteriorate theTHDof the ac current,thus lowering the power factor.Therefore,the current closed-loop for suppressing 6k±1 harmonics is essential tomeet the desired total harmonic distortion(THD).Fast repetitive control(FRC)is generally adopted;however,the deviation of power grid frequency causes delay link in the six frequency fast repetitive control to become non-integer and the tracking performance to deteriorate.This paper presents the detailed parameter design and calculation of fractional order fast repetitive controller(FOFRC)for the non-integer delay link.The finite polynomial approximates the non-integer delay link through the Lagrange interpolation method.By comparing the frequency characteristics of traditional repetitive control,the effectiveness of the FOFRC strategy is verified.Finally,simulation and experiment validate the steadystate performance and harmonics suppression ability of FOFRC.
文摘针对由电网不对称引起的Vienna整流器有功功率波动和电流不对称问题,介绍了有功功率波动的抑制控制APFSC(active power fluctuation suppression control )和对称的正序电流控制SPSCC(symmetric positivesequence current control )。由于受到功率器件的电流限制,采用APFSC会导致Vienna整流器运行的最大有功功率降低;采用SPSCC可以扩展Vienna整流器运行的最大有功功率,但有功功率波动较大。基于此,提出1种改进的功率控制IPC(improved power control )策略。当Vienna整流器处理功率较小时,以保持有功功率无波动为首要目标,此时IPC与APFSC的效果一致,对比SPSCC,IPC可有效抑制有功功率的波动;当Vienna整流器处理功率较大时,以满足功率需求为首要目标,但尽可能地减小有功功率波动,此时APFSC无法满足功率需求,但IPC可以满足有功功率需求,且在满足功率需求的前提下,对比SPSCC,IPC下有功功率的波动更小。最后通过实验验证了控制方法的优越性。
