Improved Pulse Train Control Technology Of CCM Switching Cnverter

With the development of electronic information technology,all kinds of miniaturized and lightweight electronic equipment provide a broad space for the development of switching power supply technology and put forward higher requirements.The traditional pulse width modulation(PWM)technology can't meet the demand because of the problems of slow transient response speed and difficulty design of compensation network.Pulse train(PT)control technology came into being.PT controlled Buck converter has good transient performance and steady-state performance when it works in discontinuous conduction mode(DCM),but the transmission power of the converter is relatively small.PT controlled Buck converter can transmit large power when it works in continuous conduction mode(CCM),but at this time,the pulse sequence controller indirectly regulates the output voltage through inductive current,which makes the controller have hysteresis to the output voltage regulation,leading to low-frequency oscillation and slow transient response of the switch converter.In order to solve this problem and improve the performance of PT controlled Buck converter working in CCM mode,this paper proposes a capacitor charge mode pulse train(CCM-PT)control technology.This control technology introduces capacitor current and integrates the capacitor current to ensure that the average value of the high-energy pulse period capacitor current is greater than zero,the converter output voltage rises,and the average value of the low-energy pulse period capacitor current is less than zero,and the output voltage of the converter drops,so as to effectively solve the low-frequency oscillation problem.Taking the CCM Mode Buck converter as an example,this paper analyzes its working principle,control characteristics,transient performance and steady-state performance,and carries out simulation and experimental verification.In order to solve the problem of low frequency oscillation,the dual edge current charge pulse train(DECC-PT)control technology is proposed by combining the front and back edge modulation with CCM-PT control technology,the problem of low frequency oscillation is solved,and the transient response speed of the converter is improved by changing the low energy pulse to the leading edge modulation.Taking the CCM Mode Buck converter as an example,this paper analyzes its working principle,control characteristics,transient performance and steady-state performance,and carries out simulation and experimental verification.