DEVELOPMENT OF A HIGH ACCURACY AC SAMPLING RTU DEVICE

The design of software and hardware for a high accuracy AC sampling remote terminal unit(RTU) device is presented in this paper. In the hardware, the Voltage Frequency Converter (VFC) and high performance CPU chip is used, the influence of harmonics and frequency on the accuracy of measurement is considered and can be adaptively corrected by software. The measurement accuracy for U, I, P, Q reaches the accuracy level of 0.5%. Besides, an interface for LONWORKS network is equipped in the RTU, so it can be easily interconnected.