To address the problems of low maintenance efficiency

difficulty in predicting maintenance timing

and high maintenance cost proportions in wind turbines

this paper proposes a combined maintenance strategy for wind turbines based on random shocks and multi-state degradation. Considering the effects of multiple state degradation and random shocks during wind turbine operation

the degradation process is first modeled using semi-Markov process and random shock model. Second

a multi-state combined maintenance strategy is developed

in which the degradation states of wind turbines are clarifies into normal

opportunistic maintenance

preventive maintenance

and corrective maintenance zones. Preventive maintenance

opportunistic maintenance

and corrective maintenance are jointly applied in maintenance decision-making to determine the maintenance needs of each wind turbine component

along with appropriate inspection intervals and maintenance thresholds. Simulation results show that the proposed strategy effectively reduces operation and maintenance costs of wind farms while improving the operational reliability of wind turbines.