Joint optimization of reliability design and spares inventory for a use-oriented product-service system based on the electric vehicle charging station

With the shift of business pattern from the traditional manufacturer orientation to customer orientation, the product-service system has become more and more popular. This paper takes an electrical vehicle charging station as the research object and builds a joint optimization model of reliability design and spares inventory with the objective of maximizing net profit under the constraints of availability and customer’s loss rate. Particularly, this model considers not only two types of services, namely fast charging and slow charging but also the transfer of customers between different types of service. This new model is more accordant with the practical circumstances by involving a series of elements of the product-service system simultaneously, such as the customer’s arrival, service, replacement maintenance and spares replenishment process. Then, the probabilistic indices related to reliability are derived by applying the continuous time Markov Process. A balance between the number of charging piles and spares inventory policy can be achieved by solving the joint optimization model. The influence of model parameters on these indices and the superiority of the proposed joint optimization model are analyzed in detail by numerical examples. Finally, some critical conclusions are obtained with the intent of promoting the system reliability and profit. Furthermore, this joint optimization model can be extended to more circumstances and provides guidances to solve the reliability optimization problems regarding a similar system.