Reliability model and maintenance cost optimization of wind-photovoltaic hybrid power systems

Power systems are becoming the backbone for replacing fossil energy sources in powering human life, including wind, solar, hydropower, and nuclear energy. However, a power system is intermittent, while the integration of multiple systems allows to reduce the impact of intermittency and to increase the reliability. This paper studies the wind-photovoltaic hybrid power system and its complementary strategy and maintenance cost under different failure modes and scenarios. A reliability model of the wind-photovoltaic power system is developed based on the critical wind turbine components and the topological structure of photovoltaic (PV) systems. A maintenance cost model is then derived while considering the corrective maintenance and preventive maintenance. Afterward, a maintenance optimization model is developed while incorporating some strategies of energy complementarity. Finally, a case study in Zhejiang Province, China is adopted to verify the efficiency of the proposed method, the minimum number for proper work of the PV power subsystem, and the energy complementarity between wind and PV power system.