Design Of Intelligent Medium Frequency Power Supply Based On Stm32

Induction heating is a popular heating method in industrial production.Compared with the traditional heating method,induction heating is usually of high efficiency.The non-contact heating method can realize local heating,and the low energy consumption will not pollute the environment.In the production process that needs heating in industry,the power supply for induction heating equipment is usually medium frequency power supply.In the current medium frequency induction heating power supply,the control system of induction heating power supply is mainly composed of analog or discrete digital circuits.With the improvement of industrial production process standards,it is necessary to keep the output power constant and track the resonance frequency of load in real time for the medium frequency induction heating power supply,while the traditional medium frequency power supply is difficult to meet the current output power and output frequency Rate accuracy and real-time requirements.And in the medium frequency power supply,because the non-linear power electronic devices are used as the main circuit of power transformation,many harmonics will be generated when heating,and when the output power of the medium frequency power supply increases,more harmonics will be generated,and the harm to the power grid and the equipment in the network will be greater,so it is required that the medium frequency power supply should have the ability to suppress its own harmonics.In this paper,the main circuit topology of medium frequency power supply is analyzed,and diode three-phase bridge rectifier circuit and series resonant inverter circuit are used as the main circuit topology of medium frequency power supply.Through the analysis of the power regulation mode of medium frequency power supply,the power regulation method of SPWM modulation is determined.At the same time,an improved integral separation digital PI controller is designed to realize the constant output power of medium frequency power supply.Aiming at the output frequency of medium frequency power supply,a software phase-locked-loop is designed to ensure that the output frequency of medium frequency power supply can automatically track the natural frequency of load.Through the analysis of the harmonic suppression mode of medium frequency power supply,the scheme of embedding active power filter in medium frequency power supply is determined to suppress the harmonic,and the harmonic current detection method of ip-iq and hysteresis comparison current tracking method are adopted.With STM32F407VET6 microcontroller as the core,the hardware circuit of medium frequency power supply is built,and the software design and human-computer interface design are carried out to realize the intelligent management of medium frequency power supply.Finally,through simulation and experimental analysis,the feasibility and correctness of the design scheme of medium frequency power supply are verified,which lays a certain foundation for the further application of medium frequency power supply in industry.