基于单周控制的基波磁通补偿串联混合型有源电力滤波器

介绍了基于变压器基波磁通补偿的串联混合型有源电力滤波器,将一变压器的一次侧串联在电网与谐波源之间,当串联变压器二次侧注入的基波电流与电网电流的基波分量满足补偿条件时,串联变压器可以实现对基波呈低阻抗,而对谐波呈很高的励磁阻抗,实现谐波与电网的隔离。将单周控制代替传统的滞环控制来获得补偿电流的跟踪,使得开关频率恒定,从而可以精确地设计高频滤波电容,提高系统的补偿性能和鲁棒性。推导了采用单周控制时系统的控制方程,分析了系统的工作过程。利用MATLAB对采用单周控制时系统的补偿性能进行仿真,结果表明系统具有较好的动稳态补偿性能。通过实验进一步证明了采用单周控制的可行性。

A Series Hybrid Active Power Filter Based on the Fundamental Magnetic Flux Compensation With One-cycle Control

A series hybrid active power filter based on the fundamental magnetic flux compensation of the series transformer is introduced.In the active power filter,a series transformer is chosen with its primary winding is connected in series between the power utility and harmonic producing loads.When the injected fundamental current of the secondary winding of the series transformer and the fundamental component of the utility current match the compensation condition,the series transformer can exhibit very low impedance at the fundamental frequency and high magnetizing impedance at harmonics frequency.As a result,the harmonic currents are isolated from the power utility.One-cycle control is applied to obtain the compensation current instead of the traditional hysteresis control in order to gain a constant switch frequency and the high frequency filter capacitor can be designed accurately as well as the compensation performance and robustness of the system are improved.The control equation and working process of the system with one-cycle control are proposed and its compensation performance is simulated by MATLAB.The simulation results show that the system has a better dynamic and steady compensation performance and the feasibility is also verified by the experiment results.