Research On High Dynamic Response Converter Based On Energy Recovery And Sliding Mode Control

With the development of power electronics technology,the requirement for power supplies of electronic devices changes rapidly.And power supplies with a fast dynamic response speed,an excellent unloading transient response and robustness have been considered more important.For this reason,a convertor based on the BUCK circuit with an auxiliary circuit and controlled by sliding mode control technology is designed to meet the demand.Aiming at reducing the voltage overshoot caused by an unloading transient,this paper presents a solution to control BUCK converter by an auxiliary circuit based on energy circulation structure and analyzes this solution.The circuit is simulated in SABER.The BUCK circuit with energy recovery structure based on PI control is compared with the traditional BUCK converter.As a result,the BUCK converter with the auxiliary circuit has the faster dynamic response speed and less voltage overshoot caused by an unloading transient compared with the traditional BUCK converter.The auxiliary circuit based on the energy recovery structure reduces the overshoot,but at the same time its stability is not good enough.To solve this problem,this paper designs the control loop with sliding mode control.According to the characteristics,mathematical description and the conditions of sliding mode control theory,this paper designs the system’s model based on the BUCK circuit.The circuit is simulated in SABER and the better stability of the system is verified.In order to satisfy the request of a fast dynamic response speed,a less unloading transient response and robustness at the same time,this paper combines the auxiliary circuit and the sliding mode control to design the mathematical model.The BUCK converter based on energy recovery and sliding mode control is designed by the mathematic model.The simulation experiment is proved that it has better performance.After simulation experiments,the physical circuit is analyzed and designed.The designed power supply is proved that the solution purposed in this paper has a faster dynamic response speed,a less unloading transient response and higher stability.