双变流器串-并联补偿式UPS控制策略研究

STUDY OF CONTROL STRATEGY FOR SERIES-PARALLEL COMPENSATED UPS WITH DOUBLE CONVERTERS

介绍了三相双变流器串-并联补偿式UPS的工作原理,指出了其区别于传统双变换在线式UPS的优点,提出了一种基于同步旋转坐标系下的控制策略。该策略将串联变流器控制为基波正弦电流源,而并联变流器被控为基波正弦电压源,从而实现了双变流器串-并联补偿式UPS的全部控制功能:在电源电压不是额定值且含有谐波电压、负载有谐波电流和无功电流的情况下,电源输入电流被控制为正弦波、cosf =1,负载电压被控制为额定值正弦波。连续域下的系统特性仿真结果表明该控制策略的可行性。

The operation principle of a three-phase series-parallel compensated line-interactive UPS system is presented and its merits different from the traditional double conversion on-line UPS are pointed out, and then, a kind ofcontrol manner using Synchronous Reference Frame (SRF) is proposed. By controlling the series converter as a fundamental sine current source and the parallel converter as a fundamental sine voltage source, the proposed control tactics can make this kind of UPS carry out all of the control goals: sinusoidal input current with cosf =1 and sinusoidal output voltage withnormal value in the case of non-sinusoidal, abnormal supplyvoltage and non-linear load with reactive power. The simulation results of system performance under continuous domain verify that the strategy is feasible.