基于三端口虚拟MPPT的直流耦合储能变换器控制策略研究

Research on control strategy for DC-coupled energy storage converters based on three-port virtual MPPT

基于三端口虚拟最大功率点跟踪太阳能控制器(MPPT)的直流耦合储能变换器是光伏组件阵列和光伏逆变器之间的能量匹配和调节装置,通过分析前级和后级变换器的拓扑结构和稳定性,实现前后级控制解耦。针对后级升压(BOOST)不稳定性做超前滞后补偿,保证合适的相位裕量和幅值裕度。分析了直流耦合储能变换器的虚拟MPPT输出控制策略,完美匹配存量市场的光伏逆变器,平滑光伏发电输出,移峰填谷,大幅提高自发自用效率。

DC-coupled energy storage converters based on three-port virtual Maximum Power Point Tracking(MPPT)are the energy matching and adjusting devices between PV module arrays and PV inverters.By analyzing the topology and stability of the front-end and back-end converters,decoupling of the front-end and back-end control was realized.Lead-lag compensation for the instability of back-end BOOST ensured proper phase margin and amplitude margin.The virtual MPPT output control strategy of the DC-coupled energy storage converter is considered to be a perfect match for the PV inverter in stock market since it can smooth the PV power output,shave peak load,and greatly increase the self-usage ratio.