Research On Efficiency Optimization Control Of Induction Motor Vector Control Variable Frequency Speed Regulation System

Induction motor is the major power equipment in industry, agriculture, transportation and other areas. As the energy and environmental problems become prominent increasingly, the efficiency of induction motor system is highly valued by all walks of life. The development of frequency conversion technology has played a huge role in promoting the energy-saving of induction motor system, but generally controlled with constant excitation, so the efficiency will be decreased when the motor is running steadily under no-load or light-load conditions. This paper uses induction motor vector control variable frequency speed regulation system as the object of study, in allusion to its light load steady state operating condition, studies the efficiency optimization control method in order to improve efficiency. The loss characteristic of the induction motor system is analyzed first, considering iron loss of induction motor vector control system is constructed. The fuzzy-PI control is put forward in order to improve the shortcomings of traditional PI speed control, such as easy to overstrike, slow response speed. Simulation experiments show that the fuzzy PI speed control can obviously improve the control performance of the system, laid a foundation for the study of efficiency optimization control.A new type of scale factor extraction strategy is put forward, based on the fuzzy search method on the basis of depth study of the loss model and fuzzy search efficiency optimization method. The strategy can make on-line calculation simply and effectively, and enhance fuzzy search speed. In order to solve the oscillation problem of the system in the vicinity of optimal efficiency, the membership functions of fuzzy sets are designed rationally.Comparison of the simulation results show that the method of loss model not only has the quick speed of response, but also can effectively reduce the loss of induction motor. But the motor parameter variations make the rotor flux deviate from the optimal value. The system has very good robustness based on the conventional fuzzy search method, but the convergence speed is slow. The new model of fuzzy search efficiency optimization control method put forward by the paper has dual advantages of the loss model method and fuzzy search method, and it has improved the fuzzy search speed and robustness obviously, improved the control performance of the system effectively.