基于SOC特性边界条件下VSG在光伏发电中最优控制策略研究

Research on optimal control strategy of VSG in photovoltaic generation based on SOC characteristic boundary condition

针对虚拟惯量和阻尼的取值边界会伴随荷电状态(SOC)的不同而变化的问题,提出一种基于虚拟同步发电机(VSG)控制的储能逆变器在不同SOC下变惯量、阻尼最优控制策略。分析了不同SOC下虚拟惯量和阻尼的取值边界变化情况,通过结合粒子群(PSO)和天牛须算法(BAS)构造天牛群优化算法,用来获取VSG最优虚拟惯量和阻尼值,可有效避免输出功率超限和频率振荡。仿真结果表明,相比于传统控制算法,系统输出功率超调量降低,调节时间缩短,系统会在不同SOC下自适应改变参数值,进而维持系统频率稳定,并且储能系统功率变化满足功率限制要求。

Aiming at the problem that the value boundary of virtual inertia and damping will change from the difference in state of charge (SOC), an optimal control strategy of variable inertia and damping for energy storage inverter based on control of virtual synchronous generator (VSG) is proposed under different SOC. The boundary changes of virtual inertia and damping under different SOC are analyzed. The beetle swarm optimization algorithm is constructed by combining particle swarm optimization ( PSO) and beetle antennae search ( BAS) algorithm to obtain the optimal virtual inertia and damping value of VSG. The overrun of output power and frequency oscillation can be effectively avoided. The simulation results show that compared with the traditional control algorithm, the output power overshoot of the system is reduced, the adjustment time is shortened, and the parameters of the system can be changed adaptively under different SOC, so as to maintain the frequency stability of the system. And the power change of the energy storage system meets the power limit requirements.