基于变阻尼PCH的光伏储能系统控制策略研究

Research on control strategy of photovoltaic energy storage system based on variable damping PCH

光伏储能系统中对超级电容的充放电控制决定着储能系统的性能,为了实现快速稳定的充放电控制,利用tanh函数改变阻尼系数,将变阻尼系数注入PCH模型中,实现了对储能系统的变阻尼PCH控制。推导充电过程和放电过程中系统方程,根据能量转换过程列举能量期待方程,求解了系统的稳定条件,分析不同阻尼系数对系统性能的影响。仿真和试验结果验证了提出的变阻尼PCH控制策略具有良好的动态响应性能,能够在稳态时以更小的纹波接近期望输出值。

The performance of energy storage system is determined by the charging and discharging control of super capacitor in photovoltaic energy storage system. To realize fast and stable charging and discharging control, the damping coefficient is changed by Tanh function, and the variable damping coefficient is injected into PCH model to realize the variable damping PCH control of energy storage system. The system equations in the charging process and discharge process are derived. The energy expectation equation is listed according to the energy conversion process. The stability conditions of the system are solved, and the effects of different damping coefficients on the system performance are analyzed. Simulation and experimental results verify that the proposed variable damping PCH control strategy has good dynamic response performance and can approach the expected output value with less ripple in the steady state.