| The research theme of this dissertation is the feeding system of Permanent Magnet Linear Synchronous Motors (PMLSM) and its control scheme. Base on the original thoughts, new theories and technologies of correlative subjects, a PMLSM feeding system is established. The dynamics, optimization and control strategy as well as some key technologies of the PMLSM feeding system are studied systematically by combining theoretical analysis, computer simulation with experiment.In chapter 1, the background and the significance of the research are stated. The development trend and the current research situations of the PMLSM feeding system are introduced in detail. And the main content of this dissertation is proposed.In chapter 2, based on analyzing the space vector transfer laws of the PMLSM, the mathematics model of PMLSM is built. Then the d-q model and the trust equation of the PMLSM are deduced. At last, the control method, block diagram and principle of the PMLSM rotors flux linkage orientation are obtained.In chapter 3, based on analyzing the apply force of the PMLSM feeding system, the simplified dynamic equation of the feeding system is built. The method of decreasing disturbs is proposed by optimizing the feeding system's structure. And the end force, slot force and sliding friction force are calculated and fitted through finite element method. At the end, the methods of compensating the remained disturbs by utilizing a disturb observer and identifying the model's parameters by using a state estimator are proposed.In chapter 4, the soft ware system and hardware system of the PMLSM feeding system are introduced in detail. Then the method of determining the initial position angle is presented. And the principles of forward motion, break and backward motion of the PMLSM feeding system are introduced in detail. At last, the function and choosing principle of the control loops and the low-pass filters are presented.In chapter 5, based on the theory of H∞, control strategy, the methods of determining the weighting function are emphasized and a mixed-sensitivity H∞ velocity controller is designed according to the model uncertainty and disturbance existing in the feeding system. And the stabilization and anti-disturb ability of the designed speed controller are analyzed theoretically. Simulations demonstrate that the H∞, velocity controller is much superior to the PI velocity controller in the PMLSM feeding system. And the preliminary experiment has been down in the laboratory.In chapter 6, because of the nonlinear elements existing in the PMLSM feeding system, a global-stable nonlinear controller is designed step by step according to the inner relationship between the motion equation and its parameters. Then a Lyapunov function is found to check thestabilization of the designed nonlinear controller, and the analyzing result demonstrates that the nonlinear controller is asymptotic steady. Simulations demonstrate that the performances of the nonlinear controller are much superior to those of the PI velocity controller that has been widely used in motion control.In chapter 7, the system for checking the positioning accuracy and the duplication positioning accuracy is built, and corresponding experiments have been finished and analyzed. Experiments result demonstrates that the positioning accuracy of the feeding system after compensation is greatly improved because of eliminating most of the linear error caused by manufacturing and assembling. Finally the PMLSM feeding system has been tested on a grinding machine, and the test demonstrates that it is very suitable for practical application.In chapter 8, the study contents and conclusions of the dissertation have been summarized, and the further research works have been forecast.
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