Research And Design Of Active Disturbance Rejection Control Strategy For Boost Converter

With the advancement of science and technology,as well as the constant increase of the level of automation in manufacturing,various electrical equipment has higher and higher requirements for the performance of switching power supplies.However,the traditional linear control method is no longer suitable for high precision control under interference.In recent years,more and more experts and scholars have turned their research attention to the nonlinear control strategy of power electronic converters.Among them,Active Disturbance Rejection Control(ADRC)is favored because of its good control performance and no need for accurate mathematical model characteristics.In order to analyze the typicality of the problem,this paper takes the Boost DC-DC converter as the research goal.The working process of the system in the case of continuous inductor current mode(CCM)and discontinuous current mode(DCM)is investigated in detail in this study,starting with the functioning principle of the Boost converter,and under the condition of CCM,the average state model of the converter is established by using the state space method.Secondly,according to the design requirements of the circuit,select the appropriate circuit component parameters,and then substitute the parameter information into the mathematical model,and use the classical control theory to analyze the characteristics of the system in the frequency domain.In order to improve the control performance of Boost converter,the design of converter control system is completed by using ADRC control theory.The LADRC controllers are developed for the converter’s voltage and current loops,respectively,and cascading is utilized to tackle the difficulties of limited bandwidth and poor dynamic performance caused by the converter’s non-minimum phase characteristics.Specifically,the LESO equation is established with the output voltage and inductor current as state variables,so as to realize the estimation of the system state and disturbance,and then perform feedback control through LSEF.In order to further simplify the design process,a reduced-order LADRC controller is proposed,which reduces the LESO order and the number of parameter adjustments while ensuring the control performance,which is more convenient for design implementation and theoretical analysis.The simulation results show that the system controlled by LADRC has Stronger anti-interference ability.Secondly,in view of the shortcomings of ADRC in the rapid response when the system has mismatched disturbances,it is proposed to combine ESO,the core component of ADRC,with sliding mode control method,and propose an improved sliding mode composite control algorithm based on ESO,so that the system has more advantages.Fast convergence speed and stronger anti-interference ability.Using Lyapunov stability theory,the observer and controller’s stability is explored,and the algorithm’s feasibility and effectiveness are demonstrated through simulation.Finally,using DSP as the control system’s core,the essential peripheral circuits’ software and hardware designs are finished,and an experimental platform for algorithm verification is developed.The experimental results support the proposed composite control method’s effectiveness.