Modeling and design of single ring core DC sensor based on a new readout method for DC power system protection

We proposed a new readout method for single ring core direct current (DC) sensor to protect the DC power system.The principle of this readout method is based on the linear relationship between the permeability of magnetic ring core and the DC value when the DC value changes within a small range. We built a Pspice model of single magnetic ring core DC sensor based on the proposed method to prove its correctness. We performed simulations using this model under different conditions, including reference voltage, size of core, turns per coil, excitation period, and sampling frequency. The value of the tested DC can be fitted by one linear equation multiplied by a certain coefficient, and this result was consistent with the principle of the proposed readout method. Several trial manufactures of this sensor participated in a leakage detection test. The sensitivity and noise immunity of physical sensors can be enhanced by using a micro control unit (MCU) embedded system. The correctness of this method can be confirmed using measured data.