逆变器无互联并联系统中环流抑制策略的研究

Circular Current Suppression Strategy of Parallel Connected Inverters without Interconnections

逆变器无互联线并联系统中,采用传统的PQ下垂控制法往往会引起动态性能的问题。其中最严重的问题是在调节过程中会引起逆变器输出电压的相位滞后。本文对传统下垂控制特性的局限性进行仔细分析,研究了一种双下垂特性控制方案。此控制方案解决了逆变器输出电压的相位滞后问题,同时对并联系统功率均分影响不大,并且对环流也有较强的抑制能力以及使负载电流均分。

Using traditional PQ droop control method could cause the problem of dynamic performance for inverter parallel system without internet line. One of the most serious problems is that the inverter output voltage phase lags in the adjustment process. In this paper, the limitation of traditional droop control characteristic is carefully analyzed and a kind of double droop control scheme is studied. The control scheme solves the problem of inverter output voltage phase lag. It has less effect on the parallel system power split, and has a stronger inhibitory ability to make load current homogeneous.