Edit (1) Class I substation. It refers to AC UHV station, nuclear power, large energy base (3 million KW and above) and 750 / 500 / 330kV substation connecting large regions (North China, central China, East China, Northeast China and Northwest China). (2) Class II substation. It refers to the 750 / 500 / 330kV substation, power plant outgoing substation (1 million KW and above, below 3 million KW) and inter provincial 220 kV substation, main transformer or bus outage, switch failure causing level 4 or above power grid events. (3) Three kinds of substations. It refers to 220kV substation other than class II, power plant outgoing substation (300000 kW and above, less than 1 million KW), substation with level 5 power grid event caused by main transformer or bus outage and switch refusal to operate, and substation directly supplying power to important users of level I and above. (4) Class IV substation. It refers to 35kV and above substations except class I, II and III. Note: all 220kV substations in the work area are class III substations, and all 110kV and below substations are class IV substations. Basic Requirements The basic requirements of the substation are as follows: 鈶?Define the type and function of the substation according to the power network planning, as well as the long-term and short-term construction scale (including the number of circuit lines and transformer capacity), so that the construction of substation can play the role of strengthening the power network and meet the needs of power supply. 鈶?The construction of substation requires less land, no or less arable land, and make full use of wasteland. In the distribution device layout and substation general layout, we should take the measures of less land occupation. 鈶?According to the type of substation, construction scale and the role in the power network, determine the main electrical connection, in order to improve the reliability of power supply, and try to use simple main electrical connection to reduce the construction cost and operation cost. 鈶?The facilities in the substation must meet the requirements of safe operation and convenient maintenance. All electrical equipment prone to misoperation shall be equipped with locking device to ensure the safety of personnel and equipment.Substation suppliers website:http://www.chmahalalel.com/substation/