基于可控负荷与蓄电池储能的直流配电网电压波动抑制

Voltage fluctuation suppression of DC distribution network based on controllable load and battery energy storage

为了抑制直流配电网电压波动,提出了一种基于可控负荷与蓄电池储能的综合控制策略。对影响直流配电网电压波动的因素,包括新能源输出功率变化、负荷变动、线路参数变化及新能源接入位置进行了具体分析。当电压波动较小时,利用可控负荷即可抑制直流电压波动,可以减少蓄电池的容量配置及其充放电次数,提高了储能装置的经济性;当电压波动较大时,由于可控负荷的容量有限,需要蓄电池对直流电压波动进行抑制,因此可控负荷需与蓄电池配合控制,并对两者控制参数进行了设计,采用基于扰动观测器的前馈控制,减小了直流电压暂态波动。在MATLAB/Simulink中建立了直流配电网模型并进行了时域仿真,仿真结果表明所提控制策略能够抑制上述因素造成的直流电压波动,提高直流配电网各节点的电能质量。

In order to suppress the voltage fluctuation in DC distribution network,a comprehensive control strategy based on controllable load and BESS(Battery Energy Storage System)is proposed.The factors influencing the DC voltage fluctuation are analyzed specifically,including the variation of distributed power output,load,line parameter and distributed power access location.When the voltage fluctuation is small,the controllable load can be used to suppress the DC voltage fluctuation,which can reduce the capacity of the battery and its charging and discharging times so as to improve the economy of BESS.When the voltage fluctuation is big,due to the limited capacity of the controllable load,the comprehensive control is required with BESS and their parameters are designed.The feedforward control based on disturbance observer is applied to reduce the DC voltage transient fluctuation.The model of DC distribution network is built with MATLAB/Simulink,and the time-domain simulative results show that the proposed comprehensive control strategy can suppress the DC voltage fluctuation caused by the above factors and improve the power quality of each node in DC distribution network.