DC/DC升压变换器自适应-PID串级控制系统仿真研究

为获得良好的电压控制性能,抑制模型非最小相位特性的影响,可使DC/DC升压变换器工作在电流控制模式下,采用串级结构的控制器,组成串级控制系统。系统的外环采用基于参数估计的自适应控制算法,以电容电压为被控量;内环则采用一种特殊的PID控制算法,以电感电流为被控量。此种自适应-PID串级控制器不但可使被控系统获得良好的动态特性,而且不需确知负载电阻、电容、电感、输入电压等参数的信息,对参数变化有着很强的鲁棒性。对DC/DC升压变换器的仿真结果表明,上述控制方案是可行的。

Simulation Study on Adaptive-PID Cascade Control System of DC/DC Boost Power Converters

In order to achieve high performance of voltage control and overcome the difficulties resulted from the non-minimum phase property of the model, DC/DC boost converters can be made work under the mode of current control. Thus, a cascade control system is constituted when a cascade controller is adopted in DC/DC boost converters. The outer loop of the cascade system adopts adaptive control algorithm with a parameter estimator and takes the capacitor voltage as the controlled variable. The inner one adopts a special PID control algorithm and takes the inductor current as the controlled variable. This kind of controller not only can make the controlled system achieve excellent dynamic characteristics, but also has strong robustness to the variations of system parameters, such as load resistance, capacitance, inductance, and input voltage. Simulation results of a certain DC/DC boost converter indicate that the controller presented above is feasible.