基于分布式拟牛顿法的交流微电网经济运行控制

Economic operation control of AC microgrid based on distributed quasi-Newton method

针对含多撑网逆变器的交流微电网,提出一种基于分布式拟牛顿法的经济运行控制策略,该策略包括电压和无功功率调节器以及频率和有功功率调节器两部分。采用稀疏通信网络交换相邻逆变器的信息,基于等耗量微增率准则,采用拟牛顿法根据本地和相邻节点的信息估算有功功率和无功功率的最优分配量。在电压和无功功率调节器中,无功功率的估算值可作为电流源型逆变器的参考值,或用于产生电压源型逆变器的电压修正项,实现无功功率的最优分配和电压控制。在频率和有功功率调节器中,有功功率的估算值可作为电流源型逆变器的参考值,或用于产生电压源型逆变器的频率修正项,实现有功功率的最优分配和频率控制。6节点交流微电网的仿真结果表明,所提控制策略在实现高质量电压和频率控制的同时,能够实现系统的最优经济运行,具有“即插即用”的能力,且对通信链路故障有较高的鲁棒性。

Aiming at the AC microgrid with multiple GSIs(Grid-Supporting Inverters),an economic operation control strategy based on quasi-Newton method is proposed,which includes two parts of voltage-reactive power regulator and frequency-active power regulator.The sparse communication network is adopted to exchange the information between adjacent inverters,based on the law of equal consumed energy incremental rate,quasi-Newton method is adopted to estimate the optimal active and reactive power allocation quantity according to the information of local and adjacent nodes.In the voltage and reactive power regulator,the estimated reactive power can be taken as a reference for CS-GSI(Current-Source-based Grid-Supporting Inverter)or used to generate a voltage correction term for VS-GSI(Voltage-Source-based Grid-Supporting Inverter),realizing optimal reactive power allocation and voltage control.In the frequency and active power regulator,the estimated active power can be taken as a reference for CS-GSI or used to generate a frequency correction term for VS-GSI,realizing optimal active power allocation and frequency control.The simulative results of a 6-bus AC microgrid show that the proposed control strategy can realize optimal economic operation of system while realizing high-quality voltage and frequency control,which has the capability of“plug and play”and high robustness to the failure of communication link.