Self-power current measurement method for 220kV disconnector

This paper introduces a high-precision measurement technique specifically designed for self-powered line circuits, which is fundamentally based on the principle of magnetic field intensity inversion. The core mechanism of this innovative method involves the inversion measurement of the line current, which is accomplished by precisely measuring the voltage rise time of a designated test capacitor. Additionally, this approach ingeniously leverages the energy that is stored within the test capacitor to effectively power the subsequent components in the circuit. A significant enhancement to this method is the integration of electric field energy harvesting technology, which plays a crucial role in ensuring the continuous and uninterrupted operation of the microprocessor. This integration not only facilitates the realization of high-precision current measurement but also enables efficient signal transmission, all without the necessity of an external power supply, thereby enhancing the autonomy and reliability of the system.