电源快切装置在天然气净化厂变电站的应用研究

Application and analysis of power supply fast switching device in gas purification plant substation

天然气净化厂变电站多采用双回电源供电和单母线分段接线,运行方式多为1路电源带1台变压器运行,另1路电源带1台变压器热备用,电源切换多采用电源快切装置。2021年12月20日某天然气净化厂35 kV变电站主变压器差动保护动作跳闸时,发生电源快切装置拒动事故,天然气净化厂35 kV变电站停电11 min,导致天然气净化厂发生非计划性停产,经济损失较大。通过研究电源快切装置动作原理,检测变电站电源快切装置接线和定值,发现电源快切装置备用电源进线电压互感器二次回路接线端子虚接,导致备用电源进线电压测量值偏低,引起电源快切装置发生误判而拒动;同时发现天然气净化厂35 kV变电站进线电压互感器接线和电源快切装置功能存在缺陷,提出了电压互感器接线优化和电源快切装置功能完善的改造方案。对电源快切装置拒动事故分析和应用研究,可指导天然气净化厂35 kV变电站自动装置的运维管理,提升天然气净化厂35 kV变电站自动装置的动作准确性和天然气净化厂供电可靠性。

The substations of natural gas purification plants often utilize dual circuit power supply and single bus segmented wiring.The usual operation mode involves one power supply with one transformer for operation,and the other power supply with another transformer for hot standby.The power supply switching commonly utilizes power supply fast switching devices.On December 20,2021,when the differential protection of the 35 kV main transformer in a natural gas purification plant tripped,the power supply fast switching device failed to operate,resulting in an 11-minute power outage in the purification plant substation.This led to an unplanned shutdown of the natural gas purification plant and significant economic losses.By studying the operation principle of the power supply fast switching device,checking the wiring and setting value of the power supply fast switching device in the substation,it is found that the secondary circuit wiring terminal of the standby power supply incoming line voltage transformer of the power supply fast switching device was loose and improperly connected.This resulted in a low measurement voltage of the standby power supply incoming line,causing the power supply fast switching device to misjudge and fail to operate.Additionally,the research found defects in the wiring of the incoming voltage transformer and the functionality of the power supply fast switching device in the substation.A transformation scheme was proposed to optimize the wiring of the voltage transformer and improving the functionality of the power supply fast switching device.Through the analysis and application research of power supply fast switching device failure accident,this study can guide the management of operation and maintenance of substation automation devices,improve the accuracy of the 35 kV substation automation device operation,and enhance the reliability of power supply in natural gas purification plant.