Model-free Predictive Voltage Control of Dual Active Bridge Converter Based on Adaptive Linear Extended State Observer
The model predictive control is parameter dependent,the traditional disturbance observer applied in dual active bridge converter,such as the estimation compensation,may lag behind the external disturbances,and the fixed gain is not able to adapt to the change of external wide-range disturbances.Therefore,a model-free predictive voltage control strate-gy based on adaptive linear extended state observer is proposed.Firstly,the voltage prediction ultra-local model of the dual active bridge converter is constructed by combining the predictive control and model-free control methods,instead of the traditional physical model,which reduces the parameter dependence.Secondly,the linear extended state observer is designed to provide feedback compensation for the dynamic part of the ultra-local model to improve the control accuracy.At the same time,by online fitting the voltage error trend,the observer bandwidth is adaptively adjusted to realize the over-advanced compensation.Finally,the cost function is designed to solve the optimal shift ratio for model-free predic-tive voltage control.The experimental results verify the effectiveness of the method in improving the robustness and dynamic of the system.
dual active bridgeadaptive linear extended state observerultra-localmodel-free predictive controlro-bustnessdynamics