The design theme of "the township 供电所 the supply of design. design the main contents including : 10 3 4kv 变电所 main transformer choose ; 变电所 the design electrical wiring ; short-circuit current computing ; the work load ; no power compensating ; ( 母线 and electrical equipment chosen and isolation of hv circuit switches, 避雷器 ) ; distribution device design ; relay protection plans for the protection of the design ; in charge of design should be based on electrical supply reliability, flexibility and economical to design electrical terminals and the high profile adopted by the low side, 母线 a single 母线 in the form of electrical wiring ; low side of the statistical calculations of the needs of the law to reduce wastage ; no work to improve electrical energy accessibility and the design of the transformers choose and the transformer the electric wiring and computing power ; short-circuit current calculations include short time to choose and its specific value ; and electrical equipment chosen according to the amp rating and short-circuit current computing ( use the add method now ) ; relay protection is in a design on the velocity at the protection and the protection of the current design calculations ; the design details of 10kv overhead lines have a common accident analysis and reasons for the word: Transformer choose your keywords ; electrical the relay terminals ; protection