Experimental Study on Voltage-Current Sensor embedded in Insulator

在电力公司的维护、控制和稳压调节中，对用户端电量的精确估计是迫切需要的。根据电压和电流的实际波形，有几种方法来观察功率因数。然而，传统上每个传感器都是独立安装在配电线路上的。测量系统将是大型和复杂的，导致没有维护免费系统。为了对功率因数进行波形观测，我们设计并提出了一种内置绝缘体的电压电流传感器。根据我们之前对传感器的研究，从理论上发现由于每个相位的电磁干扰，电压和电流的测量波形可能会发生严重的相移。在这个项目中，我们通过对单相配电系统、水平和垂直三相配电系统的有限元分析，研究了电压和电流传感器相移的原因。为了补偿电流传感器中的相移，我们引入了新的电流传感器线圈，它们以相反的极性相互连接，以便安装在每个相位分配线上的传感器只测量其相线上的磁链，并取消由于其他相电流而产生的磁链。最后，在理论设计的基础上，在绝缘子公司制作了上述两个线圈嵌入绝缘子的电压电流传感器样机，并通过实验验证了在模拟三相配电系统中，补偿对电流传感器相移的影响是可以得到的。

The precise estimation of the electric power at the consumer end-side is eagerly demanded for the maintenance, control and the stable voltage regulation by electric power companies. There are several approaches to the observation of the power factor based on the practical waveform of both the voltage and the current. However, conventionally each sensor has been installed on power distribution lines independently. The measurement systems will be large and complicated to result in no maintenance free systems.To carry out the waveform observation for power factor, we have devised and proposed an insulator built-in type of voltage-current sensor. According to our previous investigations on the sensor, it was found out theoretically that a serious phase shift in the measured waveforms of the voltage and the current might occur owing to the electromagnetic interference of each phase.In this project, we have investigated the cause of phase shift in the voltage and current sensors through the finite element analyses on the single phase power distribution system, the horizontal and vertical three-phase power distribution systems. To compensate the phase shift in the current sensor, we have introduced the new current sensor coils, that are connected with opposite polarity to each other so that the sensor installed on each phase distribution line will measure only the flux linkage across its phase line and cancel the flux linkage due to other phase currents.Finally, based on the theoretical design, the prototype of the voltage-current sensor embedded in an insulator with above two coils has been fabricated in the insulator company and it has been found out experimentally that the effect of compensation on the phase shift in the current sensor could be obtainable in the simulated three-phase power distribution system.