模块化不间断电源自适应均流控制技术

针对模块化不间断电源并联冗余系统的环流问题,通过引入虚拟环流阻抗,提出一种基于阻抗自适应调节的均流控制策略,具备良好的稳态及动态电流均分能力。深入探讨并机电感及控制方法对系统输出阻抗、环流阻抗的影响。在此基础上设计新颖的自适应均流控制算法,并选取合适的阻抗控制器参数,改善并联系统动态环流抑制效果。同时,滤波电感电流直流分量控制的加入有效地解决了变压器直流偏磁问题,提高了并联系统的稳定性。实验结果验证了所提控制策略的正确性和有效性。

Adaptive Current-Sharing Control Technique for Modular Uninterruptible Power Supply

The virtual circulating current impedance was introduced to suppress the circulating current existed in parallel redundant system of modularized uninterruptible power supply (UPS). This paper proposed an adaptive current sharing control strategy with excellent steady-state and dynamic performance. The influences of connection inductor and control method on the output impedance and circulating current impedance were discussed. On this basis, a novel adaptive current sharing control algorithm was designed. The effect of dynamic circulating current suppression was enhanced with appropriate impedance controller parameters. Meanwhile, the DC magnetic bias of transformer was eliminated by DC offset control of inductor current, which improved the stability of parallel system. Experimental results validate the proposed control strategy.