一种应用于高电压的温度测量系统

Temperature Measurement System Applied in High Voltage System

为使铂电阻高压测温系统测温精度符合要求,采用硬件校正和软件补偿方式解决铂电阻阻值与温度的非线性。测量系统采用A/D转换器及光纤传输解决高低压的绝缘。用温控制箱模拟一定范围的温度变化和标准温度计联用,对硬件较正电路的输出采用最小二乘法处理。试验结果证明该方法的测量误差≤±0.5°C。

Voltage transducer are the basic measurement instruments for energy measurement and relay protection in the electric power system. With the increasing demand for digitization and automation in the electric power system control and protection etc. At present, people began to show more interests on electronic voltage transducers, which are based on electronics, micro-computer and fiber communication techniques, because of their good stabilization, reliability and well-performed sensor technology. In this paper a kind of temperature measurement method for platinum resistor in highvoltage measurement system is introduced. And the nonlinearity between the value of platinum resistor and temperature is analysed. On the purpose of required accuracy, the system correct the nonlinearity between the value of platinum resistor and temperature by hardware means, combining software compensation. The measurement system adopts A/D converter and fibre transmission mode, which solve the problem that insulation between highvoltage and lowvoltage. In the simulated temperature environment witch is controlled by temperature device, this measurement method and a standard thermometer are used. At last ,the least square technique is used to dispose the output of the hardware correcting circuit. As a result , the experimental results approve the way that measuring temperature is feasible, and the measurement error range vary within 0.5℃. The voltage and temperature information is transferred by optic fiber and processed mainly in control room. The paper discusses temperature test and compensation about EVT.