基于双主动桥输入输出电流协调控制的二次纹波电压抑制策略

Secondary ripple voltage suppression strategy based on coordinated control of input and output currents for dual active bridge

单相电力电子变压器(PET)隔离级传输二次脉动功率较少且不可控,使其直流侧出现较大幅度的二次纹波电压,将影响系统供电质量以及供电可靠性。在传统双主动桥(DAB)降阶等效模型中加入开关电阻、变压器磁化电感和铜耗电阻,提升了二次脉动功率传输的准确性;在DAB控制中,电流内环采用比例-积分-谐振(PIR)控制,并引入低压直流侧二次纹波电流前馈,使高低压直流侧二次脉动功率向负载侧稳定传输,高低压直流侧二次纹波电压幅值显著减小;为加快控制器动态响应速度,对控制器关键参数进行优化设计,最后通过仿真和实验验证了所提方法的有效性。

The secondary ripple power transmission of isolation stage of single-phase PET(Power Electronic Transformer)is small and uncontrollable.As a result,a large amplitude secondary ripple voltage appears on the DC side,which could negatively impact the quality and reliability of the power supply system.The switch resistance,transformer magnetizing inductance and copper loss resistance are added to the traditional dual active bridge reduced-order equivalent model,which can improve the accuracy of secondary ripple power transmission.Moreover,in the control of DAB(Double Active Bridge),PIR(Proportional-Integral-Resonant)control is employed in the inner current-loop,and the secondary ripple current on the low voltage side is used as feed-forward compensation.Consequently,stable transmission of secondary ripple power from high and low voltage DC side to load side can be achieved,which enables greatly reduced secondary ripple voltage amplitude at high and low voltage DC sides.To improve the dynamic response of the controller,the critical parameters of the controller are optimized.Finally,the effectiveness of the proposed method is verified by simulation and experiment.