grid current

THD of the grid current is small and power factor is high at full range of loads or even in abnormal grid voltage.

全负载范围内或电网电压谐波含量大时，可实现高的输出功率因数和低的进网电流ηTHD。

A fault takes place in a network, especially asymmetric fault, lead to the grid current imbalanced and DC side voltage instability, and feed into the grid power causing oscillation, even burned PV inverter, influence safe operation of grid-connected PV system and the grid.

电网发生故障，尤其是出现不对称故障时，会导致并网电流的不平衡和直流侧电压不稳定，造成馈入电网的功率发生振荡，甚至危及逆变器，影响光伏并网发电系统和电网的安全运行。

Dual-loop Grid Current Control Technique for Grid-connected Inverter Using An LCL Filter

采用LCL滤波器的并网逆变器双闭环入网电流控制技术

PWM rectifier current-loop can be designed to guarantee stability. However, grids short-circuit impedance and distributed capacitance will affect the stability of PWM rectifier leading to grid current oscillation and a large amount of harmonics.

尽管单相PWM整流器设计时，能够保证电流环稳定，然而电网短路阻抗以及分布电容等参数将对PWM整流器的稳定性产生影响，导致电网电流振荡，产生大量的谐波。

In grid-tied mode, because of the effect of the output filter capacitor, the grid-connected inverter has high THD of the grid current and low power factor at light load.

可独立与并网双模式运行的逆变器在并网模式下，由于输出滤波电容的影响，在轻载时进网电流ηTHD高，输出功率因数低。