Resonance control method of ultrasonic machining system with integrated electromechanical modeling

Ultrasonic machining technology is widely used in precision manufacturing. However, under complex and varying machining conditions, the resonance state of the ultrasonic machining system can shift, weakening the vibration effect and seriously affecting the machining performance. To achieve rapid and accurate resonance control, this paper proposes a phase-based resonance control algorithm, implemented via PID-based closed-loop control and derived from the electromechanical lumped parameter model considering component connections. A resonant control system is constructed, and an ultrasonic power supply with the proposed algorithm is implemented on field-programmable gate array (FPGA). No-load and orthogonal milling experiments are conducted to evaluate the effectiveness of the method. The results indicate that the average frequency tracking accuracy remains within 0.17%. Compared with conventional methods, the proposed method improves the resonance control efficiency by 47.1%, decreases the average tracking error by 27.8%, and increases the average output power efficiency by 16.4%.