Research On Cooperative Control Of Microgrid Cluster Based On Communication Topology Optimization

As an important part of smart grid,the development and construction of microgrid have important strategic significance for the green energy utilization.Microgrid and microgrid cluster have more advantages of security,economic,flexible and intelligent in promoting the smart grid,but with the microgrid penetrating continuously,there are still some problems to be solved.This thesis is divided into three levels to solve the problem of microgrid cluster cooperative control.First,when the microgrid cluster access to the smart grid,the network topology of the microgrid cluster system will be more complex.And the traditional hierarchical control based on droop control due to make full use of the whole network information,makes the microgrid cluster of the high cost of energy exchange.This thesis mainly aiming at communication topology optimization problems in microgrid cluster network system,puts forward the PQL(preliminary Q-learning)algorithm,based on reinforcement learning by setting new adjacency matrix to reduce the cost of microgrid cluster of distributed collaborative control.Secondly,this thesis proposes a distributed collaborative control method for multi-microgrid system based on network topology optimization to solve the distributed collaborative control problem of microgrid cluster.The adaptive control of state of charge(SOC)of energy storage device is the first-level control.And the second-level control including current controller,voltage controller and power controller which is between the dc microgrid cluster system is implemented.Finally the three-level control based on global consistency could eliminate the voltage deviation because of the the first-level control and second-level control.Finally,the validity of the method is verified by Simulink.The simulation results show that the multilevel control structure can effectively control the power and voltage of the microgrid cluster and accomplish the cooperative operation of all parts of the microgrid cluster.