Optimization Of Reactive Powerand Control In Distribution Network Considering The Connection Of Wind-PV-ES Hybrid System

Wind energy system (WES) and photovoltaic system (PVS) are two mature generationtechnology of the distributed generations. Wind-PV-ES hybrid system is a new way ofpower generation with the association of the wind power generation, photovoltaic system,and energy storage. The hybrid generation system can take full advantage of the distributedgeneration in economic, energy, and environment. The power flow will be changed by thegrid-connection of the Wind-PV-ES hybrid system.，at the same time cause a bad impact onthe power quality and grid security. Reactive power optimization of the power system is animportant means of improving the operation efficiency, security, and power quality of thegrid. This paper gives a research on the problem of the reactive power optimization of thedistributed network that contains the Wind-PV-ES hybrid system. Finished the followingworks:1. Structure diagram and operation mode of the hybrid power system is analyzed. Havea research on the equivalent model of the hybrid system in the power flow calculation. Thepower characteristics of the doubly fed induction generator is also analyzed and it’s abilityto generate or absorb reactive power make it’s participation in the regulation of reactivepower in the power system.2．Analyze the impaction on the voltage level and active power loss of the power girdwith different location and capacity of the integrated generation system.3．Genetic algorithm is introduced, the advantage and shortage of the algorithm is alsopresented. The improved genetic algorithm and the step of using it to solve the reactivepower optimization problem is proposed finally.4．Mathematical model of the dynamic reactive power optimization with the hybridsystem is established. Considering the dynamic changes of the load and power output of thehybrid system. Improved genetic algorithm and dynamic programming algorithm is used tosolve the mathematical model. Firstly, have a division to the dynamic load and poweroutput of the hybrid system. Then, optimize the power losses and voltage deviation withoutconsidering the limitation of equipment’s regulation times using the improved geneticalgorithm. The optimal solution and several suboptimum solutions are saved as statevariables of the next optimization. At last, the equipment’s regulation times is optimizedusing the dynamic programming algorithm.5. Simulation is made in the IEEE-33distribution system and the optimization programis written using the MATLAB software. The result shows that the proposed method canobtain good convergence property and speed. The optimal plan meets requirements ofsecure and economic operation and reduces equipment’s regulation times. The proposedmethod is suitable for solving the dynamic reactive power optimization problem.