基于单片机的移相PWM功率控制超声波电源的研究

Research on phase-shifted PWM power control ultrasonic power supply based on single chip microcomputer

基于电火花超声复合加工制备金属微纳空心球的功能需求,需要在制备过程中要求超声波电源的功率、频率可调且稳定。本文设计了相应电路,主要使用STM32产生的PWM信号输出高低位电平,采用半桥驱动器IR2110驱动全桥工作,采用PID控制算法,通过调节移相角实现对输出功率的闭环控制,实现功率的稳定输出。通过实验进行验证。实验采用的换能器的固有频率为20kHz,额定功率1800W。实验测量换能器的电压约1000V,电源的工作频率达到19.77kHz,功左右,电流约3.5A,频率为20kHz。仿真和实验结果都表明,设计的超声波电源能够实现功率和频率可调的功能。

Based on the functional requirements for the preparation of metal micro-nano hollow spheres by electro-spark ultrasonic composite machining,the power and frequency of ultrasonic power supply shall be adjustable and stable during the preparation process.In this paper,the corresponding circuit is designed.The PWM signal generated by STM32 is mainly used to output the high and low level.The halfbridge driver IR2110 is used to drive the whole bridge.The PID control algorithm is used to realize the closed-loop control of the output power by adjusting the phase shift angle to achieve stable output of power.It have been verified by experiments.The natural frequency of the transducer used is 20 kHz in the experiment and the rated power is 1 800 W.The working frequency of the power supply is about 19.77 kHz and the power is about 1 750 W.The alternating voltage measured by Simulink simulation is about 1000 V,the current is about 3.5 A and the frequency is 20 kHz.The simulation and experimental results show that the designed ultrasonic power supply can realize the power and frequency adjustable function.