中文摘要：

逆变器中,电压瞬时值反馈调节对死区等因素造成的输出电压波形畸变有着很好的校正作用,但在实验中发现,对于大功率逆变器,由于滤波电感及并机电抗都很小,使得死区等因素可引起很大的谐波环流,而电压瞬时值反馈控制对这种谐波环流的抑制能力是非常有限的.该文为研究谐波环流的产生机理及瞬时值反馈控制对谐波环流的抑制作用,建立了基于谐波扰动的逆变器模型.研究表明,瞬时值反馈控制对谐波环流的抑制能力与其波形校正能力存在相互关系.通过对电压单环,电压电流双环控制的谐波环流抑制能力的比较,发现波形控制效果较好的瞬时值反馈控制,对谐波环流也有较好的抑制作用.仿真与实验验证了上述结论.

英文摘要：

In inverters, the distortion of the output sine voltage caused by factors like dead-times of power switches can be well compensated by the instantaneous voltage feedback regulators like PID controllers. However, in our experiments, we found that the dead-times could result in significant large circulating currents, and the instantaneous regulators had limited effect on restraining them, esp. in large power parallel systems where the filter reactors and output impedences must be small. In this paper, for analysis of the harmonic circulating currents, an inverter model that considered the bias of SPWM as a disturbence was established. The research of the restrain on harmonic circulating currents by the instantaneous regulators indicated that there had been relation between the output voltage distortion restrain and the harmonic circulating currents restrain by the regulators. The compare of the single loop and duel loop control demonstrated that regulators that can achieve good waveforms could also lead to the better restraining of the harmonic circulating currents. The experiments and simulation validated the conclusion.