配电网动态电压恢复器电压跌落改进补偿策略

Compensation Strategy on Improving Voltage Drop of Dynamic Voltage Restorer of Distribution Network

研究了一种应用于工业配电网系统的网侧电压跌落改进补偿策略,旨在提高敏感负荷负载侧电压品质。在分析传统超前预测补偿策略的基础上,通过DVR在初始时刻注入一个高有功功率对跌落后的电压幅值和相位进行预测存储,然后经过一个暂态寻优过程,进入最小有功模式运行,从而拓宽了最大补偿时间。相比于超前预测补偿方法,在50%跌落深度工况下,最大补偿时间可提升2倍以上。实验结果验证了所提方法的可行性和有效性,当跌落深度不超过其最大限值时,可实现直流电压的动态恢复,提升系统抗二次故障冲击能力。

A kind of improved compensation strategy for network side voltage drop of industrial distrib-ution network system is studied with purpose of improving the voltage quality of sensitive load side. On the basis of analyzing traditional advanced predicting compensation strategy. The voltage amplitude and phase after the drop are predicted and stored by way of injecting one high active power by DVR at initial moment,then are operated at minimum active power mode by way of a transient optimization search process,thus broadening the maximum compensation time. The maximum compensation time,compared to the advanced predicted compensation method and at the condition of 50% drop depth can improve above 2 times. The feasibility and effectiveness of the proposed method is verified by the experimental result. The dynamic restoration of DC voltage can be achieved with the drop depth no more than its maximum limit and therefore its ability to resist the secondary fault shock of the system is enhanced.