Optimal Sizing And Coordination Control Of Hybrid Wind/PV/Storage Power System

That the rapid development of the global economy makes the lack of energy drawn wide attention from the international community. Hence developing and utilizing the sustainable clean wind and solar energy becomes research hotspot. Wind power systems and photovoltaic systems can not generate electricity persistently because of the natural defects of wind and solar, which causes energy wastation. Construct wind and PV hybrid power system based on the complementary nature of the wind and solar is of great significance. In order to establish a great efficient wind and PV hybrid power system, make full use of resources, optimizing the allocation of system capacity is necessary.Wind and solar is random and fluctuate greatly. Reasonable control strategy is necessary to keep the system have a long-term stable operation. Charge and discharge control of the battery is the core part of the system, and detect the state of charge state is a priority part of it. This paper gives several methods to detect SOC, such as electrolyte specific gravity method, open circuit voltage method and closed-circuit voltage method,regard the terminal voltage of battery as the control parameters of the system. For power generation section, mainly control power input to the system, so as to keep the battery in a floating state. Wind power generation system takes parallel electrical control and photovoltaic system take a tandem electrical control. For the energy consumption, primarily to determine whether to load shedding based on the number of energy and how to load shedding. Adopt energy scheduling strategy based on load demand.Correct model of fan, photovoltaic cells and batteries, select the target function and constraints are necessary conditions to get an ideal optimization results. This paper gives the mathematical model of them, optimizes overall system capacity based on the total system cost, consider three goals, that is cost, LPSP and SPSP in detail, determine the number of fan, photovoltaic cells and batteries as variate, consider the battery charging and discharging, constraint functions, takes energy scheduling strategy based on load demand, improve the fitness function of genetic algorithm to solve this multi-objective optimization problem which overcomes the defect of the conventional genetic algorithm. The steps of capacity optimization of wind and solar power system are as follows: 1.According to constraint functions to determine the the number of the range of fan, photovoltaic cells and batteries so as to get genetic algorithm initial population;2.Determine the type of the fan, photovoltaic cells and batteries based on the relevant parameters;3.Gather wind, solar light intensity and temperature data in same area and calculate power based on model;4.Combine load power demand, the objective function and related constraint functions, use genetic programming algorithm to get optimization results.Use the real-time data of wind and solar from September2011to August2012to verify the validation of this scheme. According to the relevant requirements, select matching photosynthetic brand fans, photovoltaic cells and batteries, use genetic algorithms to quickly get the optimal combination. Total output curve coincide the given load power curve basically, battery charge and discharge power meet the requirements, and the corresponding LPSP and SPSP are less than5%, which is reasonable.All in all, the scheme proposed in this paper is feasible.