含分布式光伏、储能的低压配电网电压调节及储能SoC均衡方法

Voltage regulation and battery energy storage SoC balancing methodfor low voltage distribution network with distributed PV and BESS

随着可再生能源渗透率的不断提高,配电网电压波动和越限问题日益严重。为解决这一问题,文中分析低压配电网中分布式光伏电源接入对电网电压的影响,进而将节点电压幅值与节点注入功率的关系线性化;提出基于功率里程数的低压配电网电压优化模型,通过求解优化目标,计算出分布式电池储能的输出;为提升分布式储能的利用效率,设计分布式储能的荷电状态(SoC)均衡控制策略;并根据重庆巫溪地区低压配电网0.4 kV线路数据,在MATLAB/Simulink上搭建配电网仿真模型,设计4种仿真案例对所提出的模型与方法进行有效性验证。仿真结果表明,文中提出的方法能够有效地调节低压配电网中的电压并能实现分布式储能的SoC均衡控制。

With the increasing penetration of renewable energy sources,the problems of the voltage fluctuation and limitation violation has become very serious.In order to solve this problem,this paper proposes a voltage regulation method for low voltage distribution network with distributed photovoltaic(PV)and battery energy storage system(BESS).First,the impact of distributed PV sources to network voltage is analyzed and the relationship between node voltage magnitude and node injection power is deduced and linearized.Then the power mileage based voltage regulation model is constructed,with which the output of distributed battery energy storage system(DBESS)is calculated by solving the optimization target.Finally,state of charge(SoC)balancing strategy of DBESS is designed to enhance the efficiency of BESS.Furthermore,a simulation model,which is derived from a real 0.4 kV feeder in Wuxi,Chongqing,is built on Matlab/Simulink to test the effectiveness of the proposed method with four different cases.Simulation results shows that the proposed method can keep the system voltage in a normal range and can also guarantee the balance of SoC.