During its operation,the power grid voltage inevitably contains some additional background harmonic components.The presence of these background harmonics can cause distortion in the waveform of the grid-connected current when power electronic devices are connected to the grid,and may also adversely affect the safety,stability,and operational efficiency of the power grid.To address this issue,the methodology starts by establishing an impedance mathematical model of a three-phase inverter system equipped with LCL-type filter;It then delves into the specific mechanisms by which voltage fluctuations in the power grid affect the grid-connected current;Subsequently,an advanced full feed-forward control strategy for grid voltage has been engineered to counteract the detrimental influences of background harmonic voltages in the power grid on the grid-connected current;Finally,the simulation verification is carried out.After adding the strategy,the harmonic content of the grid-connected current was reduced from 7.03%to 1.46%.The results demonstrate that the proposed full feed-forward suppression method for grid voltage effectively mitigated the impact of the inverter's output current caused by background harmonics in the power grid,thereby effectively suppressing potential resonance issues in the grid-connected system.
维普
万方数据