A Novel Insulation Parameter Online Measuring Technique Based on Two Voltage Transformers for Distribution Networks
A Novel Insulation Parameter Online Measuring Technique Based on Two Voltage Transformers for Distribution Networks
复制标题
一种基于两台电压互感器的配电网绝缘参数在线测量新技术
DOI：
10.1109/tpwrd.2020.3040214
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发表时间：
2021-12
期刊：
影响因子：
--
通讯作者：
Zhan Wang
中科院分区：
文献类型：
--
作者：
Kun Yu;Siqi Liu;Xiangjun Zeng;Honghai Peng;Feng Liu;Zhan Wang
为了提高中性点不接地配电网对地绝缘参数的测量精度，提出了一种基于双电压互感器的在线测量新技术。特征频率电流信号注入配电网零序电压互感器的开口三角形侧，与电流源相等。返回特性电压信号在另一个空载零序电压Transformer的开口三角侧测量。根据注入电流与返回电压的关系，在线测量接地绝缘参数。根据特征信号的循环回路，注入电流流经绝缘参数分支，测量电压等于绝缘参数分支的电压。电压互感器的内阻抗和谐波消除不影响注入电流和被测电压，提高了测量精度。resistance.do为了验证该方法的有效性和可行性，研制了绝缘参数测量装置，并在10 kV配电网实验室和实际10 kV变电站进行了测试。实验和现场测试结果表明，该方法具有较高的测量精度。测量过程可以在不断电的情况下实现。
To improve the measurement accuracy of ground.insulation parameters in neutral point ungrounded distribution.networks, a new online measuring technique based on two voltage.transformers is proposed. The characteristic frequency current.signal is injected at the open triangular side of the zero-sequence.voltagetransformerinthedistributionnetwork,anditisequivalent.to the current source. The return characteristic voltage signal is.measured at the open triangular side of another no-load zero-.sequence voltage transformer. The ground insulation parameters.are measured online based on the relationship between injected.current and return voltage. According to the circulation loop of.the characteristic signal, the injected current flows through the.insulation parameters branch and the measured voltage is equal to.the voltage of the insulation parameter branch. The voltage trans-.former internal impedance and harmonic elimination resistance.do not affect the injected current and measured voltage, which.increases the measurement accuracy. To prove the effectiveness.andadvantagesofthemethod,theinsulationparametermeasuring.device is developed and tested in a 10-kV distribution network lab-.oratory and an actual 10-kV substation. The experiment and field.test results show that the proposed method has high measurement.accuracy. The measurement process can be realized without power.interruption.