计及脉冲分配的不对称型电流源逆变器直流侧纹波电流抑制

DC Side Ripple Current Suppression of Asymmetric Current Source Inverter Considering Pulse Distribution

单相电流源逆变器输出功率含有二倍频分量,使得直流侧功率存在二倍频波动,如果采用较小的储能电感,会产生较大的电感电流低频纹波,增大电感损耗,同时也不利于逆变器输出滤波电路的优化设计。针对这种情况,该文通过分析所设计的不对称型单相七电平电流源逆变器各电感电流在输出侧的功率分配情况,提出一种计及脉冲分配的功率前馈控制策略。仿真和实验结果表明,在满足储能电感轻量化的前提下,所提控制策略能够有效抑制电感电流低频纹波,减小输出电流低次谐波含量,验证所提逆变器和控制策略的正确性。

The output power of single-phase current source inverter contains double frequency component,which makes the power on the DC side have double frequency fluctuation.If a small inductor is used on the DC side,it will produce large low-frequency ripple of inductor current and increase inductor loss.At the same time,it is not conducive to the optimal design of inverter output filter circuit.In view of this situation,by analyzing the power distribution of each inductor current on the output side of the designed asymmetric single-phase seven levels current source inverter,a power feedforward control strategy considering pulse distribution is proposed.The simulation and experiment of the inverter are carried out.The results show that the proposed control strategy can effectively suppress the low-frequency ripple of the inductor current and reduce the low-order harmonic content of the output current under the condition of meeting the lightweight of the energy storage inductor.The correctness of the proposed inverter and control strategy is verified.