Designing And Research On Regulators In AC Adjusting Speed System With Vector Control

Asynchronous motor is a nonlinear and time-change system. It has multiple variables and the personality of strong gearing. Although vector control can solve the problem of gearing to some degree, the system is still nonlinear and time-change. What's more, during the real running course, there are many disturbance factors. So, the designing of regulators in AC adjusting speed system is the focus of researches so far.Classical PID controller is generally used in many fields of control. In its use, the method of designing PID parameters is always being studied, because the parameters have many effects on stability and performance of controlled system. In AC adjusting speed system, the method of designing regulators is still refined tothe conventional engineering designing method (EDM). In two decades recently, Genetic Algorithm (GA) is developed fast, because it can present the best solution in aspect of searching, optimization and machine learning. Because of above reason, this essay presented a new method of designing regulators on the base of studying relative documents and referring the experience of ancestors. And the new method will be used in AC vector control system oriented according to rotor magnet field. The new method will use GA to design the speed regulator and torque regulator of the system. And the magnet-link regulator will be designed using EDM.But, during the course of GA optimizing ATR, the changing of the rotor resistance which influenced the observation of torque wasn't taken into considerate, and the optimization of GA was off-line, so, when the ATR and ASR were running on-line, they couldn't get over the influence of the rotor resistance change; what's more, during the course of designing AψR, on one hand, the change of rotor resistance which influenced the observation of magnetic link wasn't taken into considerate, on the other hand, thedesigning method was EMD, so, when the AψR was running on-line, it couldn't get over the influence of the rotor resistance change, either. So, the essay analyzed the influences which the change of the rotor resistance brought to the designing result. And on the base of the analysis, the essay presented a compensation method to get over these influences.During the course of running of AC motor, the change of the rotor resistance wasn't known, so, during the course, the rotor resistance must be identified. To this point, on the base of analyzing influences and compensation, the essay presented using Neural-Network to identify the rotor resistance. Recently, artificial Neural-Network is generally used in the field of AC adjusting speed system, because it has the feature of self-recognizing, self-learning and self-adjusting. BP Neural-Network is mostly used because of its mature theory method, and at the same time, the BP algorithm is improved when it is being used. So, the essay will use the improved BP Neural-Network to identify the rotor resistance.When the essay presented simulations, fist, simulated the optimization of GA used in speed regulator and torque regulatorwithout taking the change of the rotor resistance into considerate. The result of simulation showed that this design method was feasible. Second, simulated the magnet-link regulator without thinking of the change of the rotor resistance. Then, simulated the influences of the rotor resistance bring to the system in condition of thinking of the change of the rotor resistance, the result classified that the thought of compensating is important, at the same time, it showed that it was important to identify the rotor resistance. At Lastly, the essay used unimproved BP Neural-Network and improved BP Neural-Network to identify the rotor resistance individually, then did the simulations. The results proved that the improved BP algorithm could identify the rotor resistance fast.