Study On High-power Ultrasonic Power Supply Based On STM32

The high-power ultrasonic power supply needed by former oil well processing near borehole zones has the characteristics of large capacity、stable frequency、high output power factor and comprehensive protect. In actual work, we find the key parameters of the system need real-time measurement and so related parameters need to be adjusted in real time due to complex formation condition. In actual work, due to complex conditions of formation which can storage oil, the acoustic parameters of sandstone in different sedimentary environment are different, so that acoustic system formed in different region and different strata has large differences. In order to send the high power ultrasonic vibration energy, which is stimulated in the well, into different strata with different acoustic parameters through the well fluids、casing and cement of the well casing, the key parameters of the system need real-time measurement and so related parameters need to be adjusted in real time.To meet these needs, the MCS STM32 is selected as the core of the system. Based on its precise timer, PWM output can be realized so as to provide waveform which makes IGBT work; Using the method of digital signal processing, MCS STM32 can automatically process the phase difference and amplitude ratio information of current and voltage waveforms, which are collected by STM32’s dual AD converter at the same time. Take this as the foundation, we can adjust the frequency of the transmitted waveform to the resonance frequency of probe. Ultimately frequency track and effective stimulation can be realized. Otherwise, with the help of the theoretical model,we can obtain the acoustic impedance in cased well from further processing of voltage and current.So that the acoustic impedance change during the actual work can be monitored.First, the overall design of the power system is introduced. Second the design of every part of the hardware is presented in turn according to the structure of the system, and the software implementation is described. Then the design process of the power transformer is demonstrated in detail. Increase the saturation magnetic flux density when the magnetic induction is saturated by opening air gap on the core,so that the transformer can withstand more current;Increase the effective area of the magnetic circuit,so that to meet the power transmission requirements. Calculate relevant parameters based on the basic law of magnetic circuit. Simulate the hysteresis loop of the core with air gap using matlab. At the end, the result is given. It shows that the output waveform of the IGBT gate is relatively stable. If connecting cable and transducer to the power system, the maximum current of the system can reach 94A and the voltage can reach 565V,so that the actual output electric power can reach 53kV.