Abstract：The instantaneous output power of the two-stage single-phase inverter pulsates at twice the output voltage frequency, generating second harmonic current (SHC) in the front-end DC/DC converter. To reduce the SHC, this paper proposes a virtual-impedance-based control strategy and gives a closed-loop parameter design method when adopting a resistor as the virtual impedance. To further increase the system’s bandwidth, a control strategy with band-pass filter incorporated into the inductor current feedback path is put forward and a damping resistor is added into the band-pass filter. The proposed control strategy can not only reduce the SHC significantly, but also improve the dynamic performance of the front-end DC/DC converter effectively while guarantee the converter operating in stability. Finally, a 1kV·A prototype is built and tested in the lab, and the experimental results are given to verify the effectiveness of the proposed control strategy.
张力, 任小永, 阮新波. 基于虚拟阻抗且提高系统带宽的抑制两级式逆变器中二次谐波电流的控制策略[J]. 电工技术学报, 2014, 29(6): 136-144.
Zhang Li , Ren Xiaoyong , Ruan Xinbo. Control Strategy to Improve the Bandwidth and Reduce the Second Harmonic Current in the Two-Stage Inverter Based on Virtual Impedance. Transactions of China Electrotechnical Society, 2014, 29(6): 136-144.
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