Design of Adaptive Impedance Unit for Electrical Source Emission System

This paper explores the design of an adaptive impedance unit for a wire source emission system. By examining the fundamental principles of transient electromagnetic detection and analyzing the characteristics of the emission current waveform, the study identifies key factors affecting the emission quality of electrical sources in transient electromagnetic applications. The adaptive impedance unit employs matching control to optimize the current waveform produced by the H-bridge inverter circuit, effectively reducing spikes in the original emission current waveform and improving overall emission quality. A comprehensive approach is presented, including theoretical analysis of the transient electromagnetic emission current regulation process, construction of an emission circuit simulation model, and optimization of impedance matching parameters. A low-power prototype transient electromagnetic emission system was successfully developed, demonstrating the capability to emit transient electromagnetic currents at 6.25 Hz and 12.5 Hz. Under a steady-state output current of 2 A, the peak deviation was controlled to within 2%, showcasing the effectiveness of the design.