The Design And Optimization Of Four-rotor System Based On Active Disturbance Rejection Controller

Regarding present problems of ADRC(Active Disturbance Rejection Control)that the parameters of the ADRC is difficult to adjust,the fixed parameters cannot adapt to the changes of the external environment and fuzzy parameter relationship problem exists between the extended state observer and the nonlinear state error feedback,a conjugate gradient algorithm tuning the parameters of ADRC is proposed.Thus,the problem of slow convergence and accuracy of the parameters in ADRC can be solved.The main work contents are as follows:1?the system error function constructionThe system error function is constructed by the error between the output value and the expected value of the controlled system.The search step and search direction of the function are constructed by the conjugate gradient algorithm.The five important parameters of the auto disturbance rejection controller are continuously iterated in combination with the ADRC structural equation.The ability of the controlled system to adapt to the environment is improved by accurately reflecting changes in system parameters.2?The relational function of ADRC parameters(ADRC-PRF)The mutual coupling of five important parameters in ADRC increases the difficulty of parameter tuning.The related literature only realizes partial decoupling of ESO internal parameters,and ADRC does not achieve the best control effect.ADRC-PRF realizes the fully parameterized relational function of the ADRC,solving the problem of mutual influence between parameters and difficulty of set,which will further enhance the control effect of ADRC.3?Conjugate gradient algorithm tuning the parameters of ADRC(CGA-ADRC)There are 14 parameters in the auto-disturbance controller that need to be adjusted.The parameters in the ESO part and the NLSEF part directly affect the overall control effect of the controlled system.Therefore,the dynamic setting of the above five important parameters is particularly important.Based on the system error function and the ADRC-PRF,a method of tuning the ADRC parameters by using the conjugate gradient algorithm(CGA)is proposed,which changes the fix state of the important internal parameters of the traditional ADRC.The experimental platform of the four-rotor aircraft system is built,and the stability of the four-rotor system and the attitude angle tracking are optimized.The results show that compared with the traditional ADRC?cascade PID,the proposed algorithm can quickly adjust the critical control parameters of ADRC,and the attitude control accuracy is improved by 27.6%?51.1% respectively,which verifies the effectiveness of the proposed algorithm.