The invention discloses an intelligent substation based on sensors, a communication network and an expert system. The intelligent substation comprises a substation automation system, a primary equipment condition monitoring system and an intelligent auxiliary control system. The intelligent substation is characterized in that the real-time data of equipment operation are acquired by additionally installing various sensors, the IEC61850 standard is utilized to realize information modeling of the sensor data, a communication network is utilized to build a physical channel for information transmission, and advanced application of the substation automation system and intelligent monitoring and linkage of the primary equipment condition monitoring and auxiliary systems are realized by a background expert system, thus realizing intelligent operation and patrol functions of the substation; the sensors include an all-fiber electronic current transformer, a capacitive voltage divider type electronic voltage transformer, a primary equipment condition monitoring sensor and an internet sensor with an auxiliary system things; and the advanced application of the substation automation system includes sequential control, equipment condition visualization, intelligent alarm, distributed condition estimation, substitution function and the like. Intelligent operation and patrol functions of the substation can be realized.