基于预设时间一致性的虚拟同步发电机二次电压控制

Secondary voltage control of virtual synchronous generator based on preset time consistency

针对孤岛微电网下虚拟同步发电机(VSG)一次控制存在的无功功率难以按照容量分配与电压偏差问题,提出一种基于预设时间一致性的分布式二次电压优化控制策略。该策略包含基于时基发生器的预设时间一致性算法以及与各分布式电源逆变器本体算法相结合的状态控制器,通过时基发生器将收敛时间提前确定,根据一致性算法对电压和功率输出偏差进行补偿,使逆变器仅依靠相邻单元之间的通讯即可实现无功功率分配与电压二次控制的目标。该策略无需考虑初始容量与协议参数的影响,保证了电压的定时快速恢复和无功功率的分配,同时收敛时间不受微电网容量扩展的影响,增加了微电网的灵活性和自由度。最后,通过仿真和实验验证了所提控制策略的可行性和有效性。

Aiming at the problem of power distribution and voltage deviation in primary control of virtual synchronous generator(VSG)in isolated island microgrid,a distributed secondary voltage optimal control strategy based on preset time consistency was proposed.The strategy includes the preset time consistency algorithm based on the time base generator and the state controller combined with the algorithm of each distributed power inverter body,so that the inverter can realize the target of reactive power distribution and voltage secondary control only by relying on the communication of adjacent units.This strategy does not need to consider the impact of initial capacity and protocol parameters,which ensures the timing and rapid voltage recovery.Meanwhile,the convergence time is not affected by the capacity expansion of the microgrid,which increases the flexibility and freedom of the microgrid.Finally,feasibility and effectiveness of the proposed control strategy are verified by simulation and experiment.