in this paper, a dual closed-loop ultrasonic power system based on phase inspection was researched and developed. Reliable phase closed-loop inspection circuits and the power closed-loop control system are combined in our method. To implement the power control, the PWM full-bridge output, over current protection, automatic frequency tracking and frequency adjustable function are realized by means of stm32 processor. Transducer matching circuit which uses hall sensors to achieve power control and frequency tracking dual closed-loop control system design is composed of high-frequency transformer and matching inductor. The impacts of the wave instability, the electromagnetic field, the environment temperature, severe drift problems are efficiently avoided and the structure of ultrasonic power system is simplified. This ultrasonic power system has been implemented and practically tested on ultrasonic power supply.