“…These methods mainly include expert systems [2] , artificial neural networks [3] , Petri nets [4] , Bayesian networks [5] , and so on. For example, Samimi et al [6] give the comprehensive use of sensors including electrical sensors, mechanical sensors, optical sensors, chemical sensors, and acoustic sensors to monitor the operational statuses of substations. These sensors can monitor the parameters such as current, voltage, partial discharge, gas content, temperature, and oil content.…”