Study on Calibration System for Merging Unit Test Equipments

Abstract

Today the problem of lacking effective calibration means for two key test function Indicators(delay characteristics and precision) of substation merging unit (MU) performance test equipment still exists. Under the background, this paper presents a calibration method for MU performance test equipment, develops a relevant calibration system and introduces the structure and technical indicators of the calibration system. The calibration system is based on the hardware system of high performance ARM processor, field programmable gate array (FPGA) and high precision AD chip. Then, a pre-circuit for quick sampling of voltage and current is designed to reduce sampling delay error, a high precision amplitude and phase algorithm of fixed frequency sampling is applied to realize high precision measurement of sampling signals, and a precise and flexible test strategy for delay characteristics is adopted. Finally, the comparative test of MU test equipment is carried out by using this calibration system, which basically solves the practical problem that the core performance of substation MU test equipment cannot be detected.