附录英文翻译A comprehensive overview of substationsAlong with the economic development and the modern industry developments of quick rising， the design of the power supply system become more and more completely and system。 Because the quickly increase electricity of factories， it also increases seriously to the dependable index of the economic condition， power supply in quantity。 Therefore they need the higher and more perfect request to the power supply. Whether Design reasonable, not only affect directly the base investment and circulate the expenses with have the metal depletion in colour metal, but also will reflect the dependable in power supply and the safe in many facts。 In a word, it is close with the economic performance and the safety of the people。 The substation is an importance part of the electric power system， it is consisted of the electric appliances equipments and the Transmission and the Distribution. It obtains the electric power from the electric power system， through its function of transformation and assign， transport and safety。 Then transport the power to every place with safe, dependable， and economical. As an important part of powers transport and control, the transformer substation must change the mode of the traditional design and control, then can adapt to the modern electric power system, the development of modern industry and the of trend of the society life。Electric power industry is one of the foundations of national industry and national economic development to industry, it is a coal, oil， natural gas, hydropower, nuclear power， wind power and other energy conversion into electrical energy of the secondary energy industry， it for the other departments of the national economy fast and stable development of the provision of adequate power， and its level of development is a reflection of the countrys economic development an important indicator of the level。 As the power in the industry and the importance of the national economy， electricity transmission and distribution of electric energy used in these areas is an indispensable component。Therefore， power transmission and distribution is critical. Substation is to enable superior power plant power plants or power after adjustments to the lower load of books is an important part of power transmission。 Operation of its functions, the capacity of a direct impact on the size of the lower load power, thereby affecting the industrial production and power consumption。Substation system if a link failure， the system will protect the part of action。 May result in power outages and so on， to the production and living a great disadvantage。 Therefore， the substation in the electric power system for the protection of electricity reliability, sensitivity and other indicators.Power plants and substations are connected user link in the middle, transformation and distribution of electric energy to play the role. According to the different tasks substation can be divided into stepup transformer step-down transformer substation and two broad categories。 Step-up substation built on the general power plant， the general step-down transformer near the load center built on the low.Voltage can also be divided according to medium voltage substation （60 kV and below）， highvoltage substations （110 220 kV）， EHV Substation （330 765 kV） and Ultra High Voltage Substation (1000 kV and above）。 In electric power system according to their status as a hub substation can be divided into the middle substation substations and terminals. This requires a substation part of economic rationality， the second part of safe and reliable， the only way to the normal operation of substation work services for the national economy. There are step-up transformer stepdown transformer substation and two broad categories.Substations have been equipped with various protection devices， these devices are based on lower shortcircuit load to a maximum load conditions， such as configuration settings and， therefore, in the event of the failure was similar to the specific circumstances under to judge by the system should automatically trip protection, and now the protection of the whole trip has been a very short time， the lifting of the fault， the system will automatically reclosing devices and the gateway to restore power quickly。 This is to protect the lower the load is very favorable。 This will not only protect the safety of the load equipment is in favor of extending the service life and reduce equipment investment, and improved reliability of electricity supply， which is to improve the efficiency of industrial and agricultural production is very effective。Substations have been equipped with various protection devices, these devices are based on lower shortcircuit load to a maximum load conditions, such as configuration settings and, therefore, in the event of the failure was similar to the specific circumstances under to judge by the system should automatically trip pr