电力系统冲击接地电阻测量装置

Apparatus for Measuring Impulse Grounding Resistance in Power Systems

电力系统冲击接地电阻的测量是关系到电力系统稳定运行和电气设备安全的重要问题。文中介绍了一种基于变换计算方法的冲击电阻测量装置,其测量原理是利用波头较缓、幅值较小的入射电流,通过变换计算的方法求出接地装置在波头较陡、幅值较大的雷电流波形作用下的电压响应,从而进一步求出冲击接地电阻。依照上述测量原理并考虑实际条件,文中选择了以AT89C51单片机为控制器、以门电路和高速A/D转换器构成自动数据采集子系统、以高级语言C51作为编程软件的方案。并且给出了装置的模拟测试结果和一组现场测试结果。该装置具有体积小、重量轻、工作时间长、测量思想新颖、稳定可靠等优点,同时具有波形存储和通信功能,完全满足野外杆塔冲击接地电阻测量的要求。

The measurement of grounding resistance under impulse voltage is of great importance for safe operation of power system and electronic equipment. A measuring apparatus based on the transforming calculation is introduced. By utilizing the current with flat wave head and small amplitude, the voltage response under sharp wave head and large amplitude is determined by the virtue of transformation calculation and then the impulse grounding resistance is figured out. According to the measuring principle and physical condition, AT89C51 is selected as the controller, gate and high-speed analog-to-digital converter is chosen as data acquisition sub-system, and MCS51 is chosen as program language. Finally, simulation test result and field measuring result are given. The apparatus has such advantages as small volume, lightweight, long work time, novel measuring thought and stabilization. In addition, the apparatus can store wave shape and has the communication function. It can completely meet the demand to measuring impulse grounding resistance of field tower.