A stand-alone microgrid often contains a variety of distributed generators and energy storage devices,so the coordinated operation and control are very complex.Different control strategies have significant influences on operation conditions.This paper gives full consideration to different control strategies of a stand-alone wind-solar-diesel-battery microgrid.Taking into account the initial cost,the operation and maintenance cost,the fuel cost,and the replacement cost,the optimal sizing model for stand-alone wind-solar-diesel-battery microgrid based on different control strategies is established.With the economical and environmental benefits as the optimization objectives,the non-dominated sorting genetic algorithm(NSGA-Ⅱ)is adopted to seek the optimal sizing scheme for power source types and capacities under the optimal control strategy.The results show that the method can make comprehensive assessment of the role and influence of different control strategies on optimal sizing,as well as the economic and environmental benefits of different schemes.It can clearly serve as a useful tool for optimal microgrid design.