基于故障分量的变压器浮动比率差动保护  

A New Algorithm Based on Fault Increment for Transformer Floating Ratio Differential Protection

作　　者：赵永彬[1] 陆于平[1] 

机构地区：[1]东南大学电气工程学院,江苏省南京市210096

出　　处：《电力系统自动化》2007年第13期83-87,共5页Automation of Electric Power Systems

基　　金：国家自然科学基金资助项目(50577006)~~

摘　　要：为防止变压器穿越性电流造成的不平衡电流影响,需要设置一个差动动作门槛,而变压器区内匝间故障或高阻抗接地故障却希望门槛越小越好。比率制动斜率大小的选择影响保护动作区和制动区的大小,区外故障希望斜率大些,区内故障希望斜率小些。门槛和斜率的选择直接影响比率差动保护的灵敏度和可靠性。文中深入分析比较了基于故障分量比率差动保护和传统电流比率差动保护,证明故障分量比率差动保护具有很高的灵敏度和可靠性,而且试验证明在某些故障情况下,利用故障分量的浮动比率制动较之传统的电流比率差动保护具有非常明显的优越性和实用性。A differential current threshold value is usually needed to avoid the effect of unbalancing current when the current is passing though the transformer.For ratio differential protection when a winding fault or a high impedance ground fault occurs,often it requires the value to be as small as possible.The ratio of differential protection can affect the action zone of differential current and restraint current.A high ratio is advantageous for an external fault but the small ratio is better to an internal fault.Selection of the fixed value and the ratio directly affects the protection＇s sensitivity and reliability.Hence this paper investigates the fault increment ratio differential protection and the traditional ratio current differential protection.It proves that the fault increment ratio differential protection precedes the traditional ratio current differential protection.It is also demonstrated in thepaper that the fault increment floating ratio differential protection tested by examination and simulation has much obvious superiority and practicability for some faults.

关 键 词：变压器保护 浮动比率差动保护 故障分量 灵敏度 

分 类 号：TM407[电气工程—电器]