Evaluation and Analysis of Harmonic Distortion and Reduction in Wireless Electric Vehicle Speed Control System

This paper evaluates harmonic distortion in a wireless PWM-based EV speed control system. RC low-pass filtering was implemented to suppress harmonics introduced by PWM switching and wireless coupling. Frequency and magnetic response analyses were performed using transfer functions and Bode plots. Harmonic distortion reduced from 6 dB to 0.85 dB, an 85.83% improvement, and the motor achieved 7,998 rpm with >90% wireless efficiency. These results validate the viability and stability of wireless PWM control when supported by harmonic mitigation.