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高压短路器的选用指南

2013/11/16 14:22:43      点击:
   高压断路器(或称高压开关)它不仅可以切断或闭合高压电路中的空载电流和负荷电流,而且当系统发生故障时通过继电器;ぷ爸玫淖饔,切断过负荷电流和短路电流,具有相当完善的灭弧结构和足够的断流能力。

一、选择指南

1、一般原则:

①按正常工作条件包括电压、电流、频率、机械荷载等选择;

②按短路条件包括短时耐受电流、峰值耐受电流、关合和开断电流等选择;

③按承受过电压能力包括绝缘水平等选择;

④按环境条件包括温度、湿度、海拔、地震等选择;

⑤按各类高压电器的不同特点包括开关的操作性能、熔断器的;ぬ匦耘浜、互感器的负荷及准确等级等选择;

2、正常工作

     按工作电压选择选用的高压电器,其额定电压应负荷所在回路的系统标称电压,其允许最高工作电压Umax不应小于所在回路的最高运行电压Uy,即Umax≥Uy;按工作电流选择高压电器的额定电流In不应小于该回路在各种可能运行方式下的持续工作电流Ig,即In≥Ig。

3、短路稳定

⑴短路稳定性校验的一般要求

短路电流的热效应

⑶短路稳定性校验

二、环境条件

①选择电器的环境温度

②高海拔对高压电器的影响

③地震对高压电器的影响

④额定短路开断电流的选择

⑤额定短路关合电流的选择

⑥额定操作顺序的选择

⑦额定失步开断电流的选择

⑧额定异相接地故障电流、发展性故障电流及关于开断电流的选择

⑨额定线路充电开断电流、额定电缆充电开断电流、额定电容器组开断电流、额定电容器组合关合涌流、额定感应电动机电流等选择,但使用中应按照制造厂给出的试验数据选用

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