光伏-混合储能微电网协调控制及经济性分析

Coordinated control and economic analysis on a PV-hybrid energy storage micro-grid system

微电网黑启动电源的容量和出力不足会导致系统频率和电压失稳。为此,提出采用锂电池-铅酸电池混合储能系统(HESS)作为光储型微电网黑启动电源的协调控制方法。为提高孤岛微电网长期运行能力,以HESS调度指令的低频分量作为铅酸电池的功率指令,采用铅酸电池为HESS提供容量和功率支撑;锂电池为微电网提供电压和频率支撑,充分发挥锂电池寿命长和铅酸电池性价比高的特性。在此基础上,建立投资成本和运行维护成本的HESS成本模型。电力系统计算机辅助设计(PSCAD)仿真试验验证了所提策略的有效性。

Insufficient capacity and output of black-start power supply for micro-grid will lead to its frequency and voltage instability.Therefore,a hybrid energy storage system(HESS)within lithium batteries and lead acid batteries is proposed as the coordinated control method of the black-start power supply for photovoltaic and energy storage micro-grid.In order to improve the long-term operation of island micro-grid,the low-frequency component of an HESS dispatching command is taken as the power command of a lead-acid battery.Lead-acid batteries provide capacity and power support for the HESS for their high cost performance,while lithium batteries provide voltage and frequency support for the micro-grid for their long service lives.According to the characteristics of the batteries,the cost model including investment,operation and maintenance cost of an HESS is established.Power systems computer aided design(PSCAD)simulation tests can verify the effectiveness of the method proposed.