Experimental Study on Molded Type of Voltage-Current Senser for Power Factor in Electric Distribution Systems

电力企业在维护、控制和稳定电压调节等方面，迫切需要对用户端电能进行准确的估计。根据电压和电流的实际波形观察功率因数有几种方法。然而，传统上每个传感器都是独立安装在配电线路上的。为了实现对功率因数的波形观测，设计并提出了一种绝缘子内置式电压-电流传感器，该传感器采用两个互为反向连接的电流传感器线圈。根据我们以往对该传感器的研究，理论上可以成功地补偿传统传感器中由于各相电磁干扰而产生的严重相移。虽然上述绝缘子内置式电压电流传感器具有良好的同时测量电压和电流波形的性能特性，但形成绝缘子需要经过烧制过程。为了解决这一实际生产问题，我们利用聚缩醛树脂材料设计并实现了新型树脂模塑电压电流传感器。最后，在理论设计的基础上，制作了上述两个线圈的电压电流传感器样机，并在实验室模拟的三相配电系统中对电流传感器的相移进行了补偿。

The precise estimation of the electric power at the consumer end-side has been 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 wave form observation for power factor, we have devised and proposed an insulator built-in type of voltage-current sensor with the two current sensor coils, that are connected with opposite polarity to each other. According to our previous investigations on the sensor, it was found out theoretically that a serious phase shift due to the electromagnetic interference of each phase in the conventional sensor will be successfully compensated.Although the above insulator built-in type of voltage-current sensor has good performance characteristics for concurrent measurement of both voltage and current waveforms, the burning process will be required for the formation of an insulator. To overcome such a practical production problem, we have designed and implemented the new resin molded type of voltage and current sensor using the polyacetal resin material.Finally, based on the theoretical design, the prototype of the voltage-current sensor with above two coils has been fabricated 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 in our laboratory.