多微网最优潮流功率调度及协同优化控制策略

Multi-microgrid Optimal Power Flow Dispatching and Collaborative Optimization Control Strategy

针对多微网运行中存在的一些问题,提出了多微网功率调度及优化控制策略。在该方法下,多微网被分为微网控制部分和最优潮流能量调度部分。其中,微电网控制部分包括功率优化模块以及控制模块。在功率优化模块中,提出了动态有功参考值这一概念,利用稀疏通信网络与相邻单元协作,使用一致性算法执行本地计算以求得分布式电源(distributed generator,DG)等成本微增率,获得动态有功参考值,DG输出有功则对动态有功参考值进行跟随,使发电成本最小化,同时消除频率偏差,所以此方法无需对频率进行额外的控制。除此之外,控制模块中加入了电压控制器,针对电压不一致问题,加入补偿因子,维持电压在额定值,保证电能质量。最优潮流负责子微网之间的功率调度,当子微网的容量不足时可进行功率互济。最后在MATLAB/SIMULINK中建立交流多微网,仿真结果表明,所提方法有效地提高了系统的经济性和稳定性。

In allusion to the problem existing in multi-microgrid operation,a multi-microgrid power dispatching and optimization control strategy was proposed.In the proposed strategy,a multi-microgrid was divided into two parts,i.e.,the microgrid control part and optimal power flow energy dispatching part.The microgrid control part included power optimization module and control module.In power optimization module a concept of dynamic active power reference value,in which the sparse communication network was cooperated with adjacent unit,was put forward,and the consistency algorithm was utilized to perform local calculation to determine equal cost incremental rate of distributed generator(abbr.DG)to obtain the reference value of dynamic active power.The active power of DG output followed the dynamic active power reference value to make the generating cost minimized,meanwhile the frequency deviation was eliminated,and therefore with such a method the additional control of frequency was not needed.Be-sides,the voltage controller was added in the control module and aiming at voltage inconsistency the compensation factor was added to maintain the voltage at the rated value to ensure the power quality.The optimal power flow was responsible for the power scheduling among sub-microgrids,when the capa-city of sub-microgrid was insufficient the mutual aid of power among sub-microgrids could be conducted.Finally,an AC multi-microgrid model was established by MATLAB/SIM-ULINK,and the simulation results show that using the pro-posed method both economy and stability of the system were effectively improved.