Research On Maintenance Decision Making Optimization Based On Risk For Distribution Transformer

This article described the background distribution network condition-based maintenance. The necessity to executive condition-based maintenance on the distribution transformers, acting as one of key equipment in the distribution, is also expounded. After the analysis and comparison of the popular condition based maintenance concept nowadays, Risk Based Maintenance(RBM) is gaining traction around the world because of its advantages. It can both take the reliability and economy of the equipment operation into account. According to the concept of risk,risk assessment of power systems is not only to assess the severity of the failure probability but also the failure events’ consequence. In order to describe the aging process of the equipment, this paper presents an outage probability model based on Multi-state Markov process. Considering the effect of preventive maintenance on probability, the model is revised. Different types of load with the same size of the load loss cause different grid profit loss. Accordingly grid profit loss model is established accounting the load type. Taking the failure risk and the maintenance risk and the grid security constraints, maintenance resource constraints, while maintenance constraints constraints into consideration, the distribution transformer’s maintenance plan optimization model based on risk is established. Artificial bee colony algorithm can balance the exploration and mining process food source in the process of search. It can perform global and local search simultaneously. And then the probability of convergence to local optima is reduced in some extent. But as an intelligent algorithm,it has slow convergence and local optimum shortcomings inevitably. In order to solve the artificial bee colony algorithm’s slow convergence and falling into local optimal point, the chaotic search operator is introduced into the artificial bee colony algorithm.And the test function is used to verify the superiority of the optimization algorithm.The improved is used to solve transformer’s maintenance plan optimization model.Finally, taking RBTS-BUS2 system as an example, artificial bee colony algorithm based on chaotic search is used to optimize the 22 transformers’ maintenance plan.And then the proposed model and algorithm is verified to be rational and effective.