摘要
针对煤矿井下中性点绝缘低压供电线路中,由于电网对地分布电容的存在,使漏电电流或人身触电电流超过极限安全值,并且电网分布电容的多变容易引起原系统过补偿或欠补偿的情况,提出基于最小漏电电流闭环控制理论的电感量粗调和细调相融合的自动补偿方案,采用单片机控制继电器自动切换磁放大器多抽头交流绕组实现电感量有级调节,通过步进电机调节电位器改变磁放大器直流绕组的电流,实现电感量无级调节,从而使流过磁放大器的电感电流完全补偿电网分布电容的电流。该系统补偿速度快、精度高、调整周期短,补偿过程操作方便、安全。
In neutral insulation low voltage power supply lines of coal mine,due to distributed capacitance exists, the leakage currents or personal electric shock currents exceed the limited safety value, and the changes of distributed capacitance easily cause the original system overcompensation or under compensation. The automatic compensation scheme of combining inductance the coarse adjustment with the fine adjustment is proposed on base of the minimum leakage currents closed loop control theory. Using single chip microcomputer control relay automatic switching magnetic amplifier is to achieve multi tap AC winding inductance step adjustment. The currents of magnetic amplifier DC winding are changed by single chip microcomputer control step motor to adjust potentiometer. The system attains stepless regulation of the inductance, so that the currents of distributed capacitance are completely compensated by the inductor currents of the magnetic amplifier. It has many advantages of fast compensation speed, high precision, short cycle, safety and easy operation during compensation process.
出处
《山西焦煤科技》
2014年第12期4-7,共4页
Shanxi Coking Coal Science & Technology
关键词
漏电保护
容性电流
自动补偿
Leakage protection
Capacitive current
Automatic compensation