HV circuit breaker state assessment based on gray-fuzzy comprehensive evaluation

As the factors of HV (High Voltage) circuit breaker state assessment are fuzzy and gray, the gray-fuzzy theory is applied to it. A hierarchical evaluation model considering the operational mechanism is established based on a pilot project of HV circuit breaker. The weight set of each assessment factor at different levels is composed of fuzzy part and gray part. Its fuzzy part is calculated based on the AHP (Analytic Hierarchy Process) and its gray part is determined based on the redundancy degree of information and the experiences of experts. The fuzzy relation between assessment factor and state grade is described by the membership degree to combine qualitative analysis and quantitative analysis. The incredibility of fuzzy relation is described by the pixel gray scale to establish the gray fuzzy discrimination matrix for the comprehensive assessment of HV circuit breaker state. The practical calculation example shows that the proposed model can objectively and effectively assess the state of HV circuit breakers. ©, 2014, Electric Power Automation Equipment Press. All right reserved.