电池储能抑制直流配电网振荡的控制策略研究

Oscillation suppressing control strategy of DC distribution network using battery energy storage system

与交流配电网不同,直流配电网的振荡特性主要由直流电压或直流电流的振荡特性体现。针对恒功率负荷接入含有直流限流电抗器的直流配电网所引起的振荡现象,本文首先采用简化模型分析引起直流配电网振荡失稳的机理;其次,通过分析电池储能双向充放电运行原理,提出一种采用电池储能装置抑制直流配电网电压振荡的策略,该策略是反馈接入点的直流电压至高通滤波补偿器,将产生的补偿电压与电流环产生的电压叠加之后生成功率器件的调制波;最后,采用电磁暂态仿真模型,验证了电池储能在充放电双重模式下均具有抑制直流配电网振荡的性能。

Different from AC distribution network,the oscillation characteristic of DC distribution network is reflected by DC voltage or DC current.It must be presented by the DC voltage if there is an oscillation phenomenon in DC distribution network.In view of the oscillation phenomenon caused by the constant power device connected to the DC distribution network with DC current limiting reactor,this paper first analyzes the mechanism of the oscillation instability of the DC distribution network by using a simplified model.Secondly,by analyzing the bi-directional charging and discharging operation principle of battery energy storage,a strategy of using battery energy storage device to suppress voltage oscillation of DC distribution network is proposed.This strategy is to feed back the DC voltage of the access point to the high pass filter compensator.The compensation voltage produced by the high pass filter compensator is superimposed to the voltage generated by the current loop to form the modulation wave of the power devices.Finally,the electromagnetic transient simulation model is used to verify that the battery energy storage can suppress the DC distribution network oscillation in the dual mode of charging and discharging.