Abstract: According to the actual needs, a digital ultrasonic power supply with a rated power of 2000 W was designed. STM32F767 was used as the main controller of the intelligent digital ultrasonic power supply to complete the control and processing of the entire power supply. According to the characteristics of the transducer, an LC series matching circuit was designed to realize the resonance matching of the transducer. According to the requirement of impedance matching, a high-frequency transformer was designed to realize the matching of the output impedance of the inverter. In order to solve the problem of automatic adjustment of the tracking direction in the process of frequency tracking, a direction adaptive variable-step frequency tracking algorithm was designed to realize the automatic adjustment of the frequency tracking direction. The composite power control algorithm of "open-loop + closed-loop" was utilized to effectively regulate the output power. Finally, the actual test results show that the intelligent digital ultrasonic power supply can meet the design requirements and has stable performance.