Abstract: In response to the problem of difficulty in covering urban electricity in small and medium-sized island areas far from the mainland, this paper proposes an improved offshore solar energy, and wind energy complementary power generation system. An improved variable step conductance increment method was adopted for maximum power point tracking in the photovoltaic subsystem; A control strategy combining a speed deviation compensator and a double power exponential approaching law sliding mode control was designed for the non working area of the wind turbine power generation electronic system. The entire system was modeled and simulated in MATLAB/Simulink simulation software, verifying the correctness and effectiveness of the multi energy complementary power generation system.