| Based on the research of model-free adaptive control(MFAC),this paper optimizes the calculation of control law and improves the model-free adaptive control algorithm for the problem of system which accompanies noise interference.A new method for calculating the control law combined with the output error rate and an anti-noise model-free adaptive control approach based on the improved tracking differentiator are proposed respectively.The proof of the convergence of input and output of the above two improved algorithms is also given.Finally,the effectiveness of the above two improved algorithms is verified by simulation,and the application of the above two improved algorithms is studied to a certain degree.The main research contents and results of this paper have the following three aspects:Firstly,in order to make the MFAC method better solve the problem of system accompanying noise interference,this paper introduces an improved tracking differentiator in the feedback process,furthermore,an anti-noise model-free adaptive control is proposed.At the same time,the paper also gives the proof of the convergence of the input and output of the anti-noise MFAC algorithm.For some typical nonlinear systems,numerical simulations show that the proposed method preserves the excellent characteristics of the MFAC method while removing noise interference.Finally,combining with the control of the drum water level of the circulating fluidized bed(CFB)boiler,the application direction and prospect of the proposed algorithm are explained.Secondly,this paper introduces the idea of output error rate based on the calculation of the original control law,and assigns the corresponding weights of output error and output error rate,respectively.This paper further optimizes the control law calculation of MFAC algorithm.At the same time,the paper also gives the proof of the convergence of the input and output of the MFAC algorithm based on the new control law which aims to show the rationality of the algorithm.For some typical nonlinear systems,the MFAC method based on the new control law is compared with the original MFAC method.The simulation results show that the model-free adaptive control algorithm based on the new control law can track the given signal more quickly,and the tracking performance of the MFAC method is further improved.Finally,for the nonlinear problem of Li Br absorption chiller,this paper applies the MFAC method algorithm based on the new control law to the control system of Li Br absorption chiller.Then,using TRNSYS software to establish a dynamic model of Li Br absorption chiller and writing MFAC method into MATLAB.In the end,dynamic simulation is completed by using MATLAB and TRNSYS.For the application of MFAC in the chiller,the research done in this paper has certain guiding significance,which provides a new idea for the control of Li Br absorption chiller,and further expands the development of MFAC in the control direction of Li Br absorption chiller. |
