电压型非理想Buck变换器的DCM模式建模与仿真

Modeling and simulation of voltage-controlled non-ideal Buck converter in DCM

文章对DCM模式下的非理想Buck变换器进行全阶建模,提高了模型的精度,在此基础上,针对Buck变换器开环系统动态响应慢、相位裕度差等缺点,设计相应的PID控制网络。通过比较补偿前、后控制-输出传递函数的频域仿真,证明所设计的控制器能够改善Buck开环变换器的性能;通过在Simulink中对电路模型和实际电路的仿真比较,验证了文中建模方法的可行性,从而为DC-DC变换器及系统控制电路的设计提供了理论依据。

A full order modeling of non-ideal Buck converter operating in discontinuous-conduction mode（DCM） is conducted, which improves the accuracy of the model. Considering that the dynamic response is slow and the phase margin is bad in the open loop system, a PIE） controller is designed. By comparing the frequency domain simulation of control-output transfer function before and after the compensation, the controller is verified to be effective in improving the performance of converter. The proposed circuit model and the actual circuit are simulated in Simulink respectively. The results show the reasonableness of the presented modeling method, which gives guidance for DC-DC converter and control circuit design.