浅析变压器压力释放保护

Analysis of transformer pressure protection

变压器压力释放保护,作为变压器的非电气量保护,其保护原理是当油箱内有故障的时候,油箱本体上压力释放阀的微动开关动作接通变压器跳闸回路来实现对变压器的保护。即当故障点发生在变压器内部时,变压器油被汽化,产生大量的气体,同时由于变压器油箱内油的体积急剧膨胀,使变压器油箱内部压力迅速上升。当变压器油箱内部压力升高到变压器压力释放阀设定的压力时,变压器压力释放阀微动开关迅速闭合,同时变压器压力释放阀在2毫秒内立即打开,使变压器油箱内的压力急剧下降。与此同时变压器压力释放阀微动开关迅速动作闭合,使变压器跳闸出口回路接通,跳开变压器各侧断路器。从而防止了变压器故障的进一步扩大。但在现场实际运行中,经常发生变压器压力释放保护误动作的事故。本文从现场运行实际出发,对变压器压力释放保护作出一定的比较分析,为现场运行提供指导。

Transformer pressure release protection,as the transformer of non electric quantity protection, the protection principle is when fuel fault,the tank body pressure release valve of the micro switch action connected to the transformer tripping circuit to realize the protection of transformer.That when a fault occurs in the transformer,transformer oil is vaporized to produce large amounts of gas,also due to the rapid expansion of the volume of oil in the oil tank of the transformer,the transformer oil tank internal pressure is rising rapidly.When the transformer oil tank internal pressure rises to transformer pressure release valve set pressure,the transformer pressure release valve fretting switch quickly closed,also transformer pressure release valve in 2 milliseconds immediately opened,the transformer oil tank pressure drops sharply.At the same time the transformer pressure release valve fretting action quickly closed switch,transformer tripping outlet loop is switched on,all sides of the transformer circuit breaker is tripped.In order to prevent the further expansion of the transformer fault.But in the actualoperation, fre quent transformer pressure protection misoperation accident.This paper proceeds from the reality of field operation of transformer pressure release protecting make some comparative analysis,provide guidance for field operation.