Research on Broadband High Precision Voltage Ratio Measurement System
Yue Chang-x · Electrical Measurement & Instrumentation · 2013
To study the influence of harmonic effects on error characteristics of the power transformer, the paper develops a broadband high precision voltage ratio measurement system. It is based on Labview and dual-channel digitizer NI PXI-5922, and utilizes channel switching technique. The overall structure and principle of the system are introduced, and the error, frequency response and stability of the system are tested. Results indicate that the ratio measurement error is reduced effectively with the application of channel switching technique. The system's ratio error is lower than 1×10-6, and phase error is lower than 0.1 μrad when the phase between the two measured signals is close. And its frequency response is very flat between 60 Hz to 10 kHz. The ratio measurement performance of this equipment is greatly improved compared with similar devices.