电力系统保护与控制
電力繫統保護與控製
전력계통보호여공제
Power System Protection and Control
2015年
17期
51-56
,共6页
赵军%袁雪琼%扈海泽%王林%阮琦%张春辉
趙軍%袁雪瓊%扈海澤%王林%阮琦%張春輝
조군%원설경%호해택%왕림%원기%장춘휘
中低压配电网%可变电阻%对地电导%对地电容%精确测量
中低壓配電網%可變電阻%對地電導%對地電容%精確測量
중저압배전망%가변전조%대지전도%대지전용%정학측량
low-voltage distribution network%variable resistor%grounded conductance%capacitance to ground%accurate measurement
为了获得配电网精确对地参数,提出基于变电阻电压扰动法的电网对地参数测量方法。对于中性点不接地系统、中性点经消弧线圈接地系统,由于系统正常运行时参数的不平衡,将在中性点产生一定的电压偏移。通过在中性点投入不同阻值的电阻,引起中性点电压的改变,测量改变前后的电压幅值,由电压幅值和其他已知参数通过一定的运算可先计算出配电网对地电导,将电导代入再求出系统对地电容精确值。Matlab仿真分析和实验模拟网测试结果表明该方法具有很高的精确度,且该方法简单、安全、适用范围广、可操作性强。同时指出实际现场测量时,应选用适当阻值电阻,以减小测量误差。
為瞭穫得配電網精確對地參數,提齣基于變電阻電壓擾動法的電網對地參數測量方法。對于中性點不接地繫統、中性點經消弧線圈接地繫統,由于繫統正常運行時參數的不平衡,將在中性點產生一定的電壓偏移。通過在中性點投入不同阻值的電阻,引起中性點電壓的改變,測量改變前後的電壓幅值,由電壓幅值和其他已知參數通過一定的運算可先計算齣配電網對地電導,將電導代入再求齣繫統對地電容精確值。Matlab倣真分析和實驗模擬網測試結果錶明該方法具有很高的精確度,且該方法簡單、安全、適用範圍廣、可操作性彊。同時指齣實際現場測量時,應選用適噹阻值電阻,以減小測量誤差。
위료획득배전망정학대지삼수,제출기우변전조전압우동법적전망대지삼수측량방법。대우중성점불접지계통、중성점경소호선권접지계통,유우계통정상운행시삼수적불평형,장재중성점산생일정적전압편이。통과재중성점투입불동조치적전조,인기중성점전압적개변,측량개변전후적전압폭치,유전압폭치화기타이지삼수통과일정적운산가선계산출배전망대지전도,장전도대입재구출계통대지전용정학치。Matlab방진분석화실험모의망측시결과표명해방법구유흔고적정학도,차해방법간단、안전、괄용범위엄、가조작성강。동시지출실제현장측량시,응선용괄당조치전조,이감소측량오차。
In order to obtain accurate grounded parameter of distribution network, a method of measuring grounded parameter of power grid based on variable resistor voltage disturbance is put forward. Due to the unbalanced parameters during system normal operation, voltage will deviated in the neutral point for neutral point grounding system and neutral point via arc suppression coil grounded system. By adding resistors with different resistance in the neutral point to change the neutral point’s voltage, this paper measures the voltage amplitude before and after the change, uses the voltage amplitude and other known parameters by certain operations to calculate the distribution network grounded conductance, and substitutes conductance into the equation to obtain accurate grounded capacitance. Matlab simulation analysis and experimental test results show that the method is highly accurate, simple, safe and has wide application and operability. It also points out that appropriate resistance values should be chosen in actual measurement to reduce the measurement error.