Reliability analysis of autonomous controllable protection device in power system

With the deepening of the concept of autonomous control in the power system, more and more attention is paid to the stability of the protection device itself. Compared with the primary equipment condition monitoring, the fault of the secondary protection device will be more concealed. This paper analyzes the factors affecting the reliability of protection devices, forms the life cycle prediction method of substation protection devices, and ensures the safe and stable operation of intelligent substation. Analyzed the reliability of the relay protection device related concepts, from the failure mechanism, through the establishment of joint aging failure based on the Arrhenius model and Weibull distribution model, and based on grid relay protection device, the data is using LM method for joint failure rate estimate the parameters of the model, get old equipment failure rate model of concrete, to determine the reliability of the protection device and the effective service life. An example shows that the model proposed in this paper can effectively predict the failure trend and life boundary of the device, and provide a theoretical basis for the daily maintenance of smart substation.