新型配电变一体化静止无功补偿技术研究

Research on novel technology of distribution transformer and static VAR compensator integration system

针对我国配电网及箱式变电站无功补偿所存在问题,提出了一种融合配电变压器和静止无功补偿单元的一体化无功补偿技术(Distribution Transformer STATCOM,DT-STATCOM)。该技术充分利用配电变压器的富余容量,动态补偿变压器及其负载的无功消耗;通过灵活的接入电压选择,扩展了补偿单元电力电子器件的选型范围;紧凑的一体化结构也有效降低了补偿装置的体积和成本,提高装置整体效率。介绍了DT-STATCOM的结构形式,并针对该特殊结构,提出了两种跨端口瞬时无功功率(电流)的检测方法。仿真和实验结果表明,DT-STATCOM技术对配电网无功动态补偿和综合电能质量控制有着显著的效果。

According to the reactive compensation feature of distribution network and box-type substation, this paper proposes an integration structure of distribution transformer and STATCOM （DT-STATCOM）. It uses the surplus capacity of transformer to compensate the reactive power; by setting the connection voltage flexibly, it extends the range of the switching devices selection; the integration structure reduces the volume and cost of compensation device effectively. This paper introduces the structure of DT-STATCOM and proposes two instantaneous reactive current detection methods across the transformer’s ports. Simulation and experimental results show that DT-STATCOM system has significant effect on dynamic reactive power compensation and comprehensive power quality control.