Research and design of precise voltage conversion unit for low-voltage output sensor

In order to solve the problem of traceability and error calibration of low-voltage output signal equipment, such as active electronic voltage transformer and voltage sensor in primary and secondary fusion equipment of distribution network, etc. In this paper, a precision voltage conversion unit which can realize reverse phase and 1:10 arbitrary proportion voltage conversion unit is developed. The feedback loop to realize differential dynamic follow of output signal to input signal and the two-stage induction coil with multistage shielding and quadratic proportional superposition are designed in this paper. The error analysis and test of the precision voltage conversion unit are carried out. The maximum output ratio error is 42ppm and the maximum angle error is 24urad at 1:1-1:10 scale.