Research And Implementation Of Synchronous Buck Converter Digital Control

Switching power supply in industrial production and life widely used,the traditional switching power supply to simulate the main control,there are some shortcomings and deficiencies.With the continuous improvement of the frequency of the digital controller,the price declining,and the increase in computing power,switching power supply digital control has become a new trend in the development of switching power supply.This paper mainly studies the digital control technology of synchronous buck converter.Firstly,the synchronous buck converter is used as the research object,the working principle is analyzed,the mathematical model is established,and then the simulation analysis is carried out.Simulation tools using the new power electronic simulation software StarSim and graphical programming software LabVIEW,graphical programming environment can be more intuitive display of the structure of the algorithm.In the algorithm,select the PID algorithm and pole configuration algorithm.The method of combining pole assignment and integral separation is proposed,which not only ensures the system has good starting performance,but also eliminates the steady state error of the system.Finally,two control algorithms are implemented by simulation,and the comparison is analyzed.The simulation results show that the performance of the pole placement algorithm is more advantageous than the PID algorithm in the start,anti-power disturbance and anti-load disturbance.In the simulation analysis,the principle of PID algorithm and pole assignment algorithm is introduced in detail,and how to write PID algorithm and realize pole assignment through state feedback control in LabVIEW.The method of implementing carrier comparison,dead time and ripple calculation with LabVIEW is described.In order to further verify the algorithm to STM32 as the master chip,the actual production of synchronous buck converter control prototype.Respectively,introduced the control circuit,power circuit,drive circuit,signal conditioning circuit design process and design points.Focusing on the switching power supply PCB design process and design specifications.Finally,STM32 on the realization of the above two algorithms,given the programming flow chart.The results show that the proposed algorithm is consistent with the simulation analysis,which verifies the correctness of the simulation analysis and proves the superiority of the pole placement algorithm.