Maintenance optimization of generating equipment based on a condition-based maintenance policy for multi-unit systems

In a competitive market environment, privatized generating companies are pressured to more efficiently maintain their generating equipment in order to maximize their profit. As a result, condition based maintenance is becoming popular and highlighted by researchers and practitioners in power plants due to its advantages of improving maintenance efficiency and avoiding unnecessary maintenance. A new condition based and opportunistic maintenance policy is proposed for multiunit systems (e. g. a generating unit) in this paper. Under this maintenance policy, the deterioration processes of equipment are discrete and modeled using continuous time Markov chains, and maintenance decisions are given based on deterioration states of equipment. With the application of the proposed policy, the maintenance activities of generating equipment can be optimized for maximizing the profit of a generating company over a finite time span, considering the variations of prices and sold/bought volume of coals, electricity, and heat in the future. The Monte Carlo simulation model of the maintenance policy is also given in detail. By a numerical example, the application of the proposed maintenance policy to the optimization of condition based maintenance in a thermal power plant is illustrated.