摘要
电网电压前馈策略能有效抑制公共耦合点(PCC)电压谐波引起的逆变器并网电流畸变问题,但在实际中多采用比例前馈或在全前馈中引入额外的有源阻尼,易造成前馈误差。在此以弱电网下的LCL型并网逆变器为研究对象,推导了考虑电容电流反馈有源阻尼的电网电压全前馈策略,从频率响应角度分析了采用部分前馈时的误差问题,并提出微分近似控制器以实现全前馈中的微分项。最后,通过仿真和实验验证了理论分析的正确性和所提方法的有效性。
Grid voltage feedforward strategy can efficiently suppress grid-side current distortion of inverters caused by harmonics in point of common coupling(PCC)voltage.However,in real applications,proportional feedforward or fullfeedforward strategy with extra active damping methods are usually applied,which will cause feedforward errors.Based on the grid-tied inverter with LCL filter in weak grid condition,the grid voltage full-feedforward strategy with consideration of the capacitor-current-based active damping method is firstly deduced.Then,the feedforward errors of partial feedforward methods are analyzed and compared according to the frequency response of each term.To realize the derivative terms in full-feedforward strategy,an equivalent derivative controller is proposed.Finally,the correctness of theoretical analysis and the effectiveness of the proposed method are verified by simulation and experimental results.
作者
查晓宇
徐军忠
王勇
ZHA Xiao-yu;XU Jun-zhong;WANG Yong(Shanghai Jiao Tong University,Shanghai 200240,China)
出处
《电力电子技术》
CSCD
北大核心
2020年第4期84-87,共4页
Power Electronics
关键词
并网逆变器
弱电网
全前馈
grid-connected inverter
weak grid
full-feedforward
