A Novel Self-Powered Smart Current Sensor for Power Equipment
Current measurement is one of the most important work in online monitoring of the electric system. Self-powered and intelligence are key areas of the current measuring sensor. In this paper, a self-powered current measuring sensor realizing measurement and power supply synchronously was designed. The different functions of current transformer were integrated and the mathematical relationship between the line current and the CT secondary side output was deduced. The model for current measurement based on different signals before or after the rectifier bridge was constructed. The overall design of the current measuring equipment was given. Finally, the accuracy of different measuring models was verified by experiments and test results under load changes were analysed.