| Double-fed motor speed regulating system is a variable-frequence speed regulating system, which makes use of the rotor AC excitation control of the motor speed, including the motor body and the AC excitation system. Compared with the ordinary variable speed drives with signal fed induction machine, it has many advantages such as small capacity with variable-frequence device, low voltage, adjustable power factor, low reconstruct expenses, predominant performance of variable speed factor and so on. But the AC motor of double-fed exists nonlinear factors such as magnetic hysteresis and saturation. It is very important to understand nonlinear problem in motor research, and solve this problem also become one of the important issues which blocks motor development.Firstly, this paper introduced the energy waste caused by magnetic hysteresis and saturation arrive seriously, and energy problem has became the problem that every country of the world is working to solve. It can improve the motor operating efficiency and the rate of energy utilization efficiency via solving the nonlinear problem on motor, which is not only become the crucial issues in motor development, but also have great energy and social benefits to the entire country. To solve the motor's magnetic hysteresis and saturation question, firstly, we must have a adequately acknowledge at motor magnetism characteristic and establish effective motor model. This paper introduced the means of derivative genes of nonlinear magnetic linkage to linearity magnetic linkage which get the nonlinear motor model linearization., to establish the nonlinear motor mathematical model with relative accurate and effective consideration of magnetic hysteresis and saturation. The paper used the simulation on Matlab/Simulink platform which is establish the mathematical model to verify the simulation result is whether in accord with the theoretical analysis.In this paper, it will take the created motor mode applied to the system of double-fed motor speed regulation which can create the system of double-fed motor speed that considering the hysteresis nonlinear. It take the AC-DC-AC topologies structure to established the frequency converter that used in the control of double-fed motor. The frequency converter included the AC/DC rectifier mode and DC/AC inverter. The AC/DC mode adopt the means of vector control technology and SPVWM pulse width modulation mode to drive the rectifier. The DC/AC mode adopt the manner of stator magnetic field orient method which make M-T shaft the coordinates fasten of M shaft and the stator magnetic linkageψl coincidence. It takes the active component and reactive component respectively controlling. According to the stator magnetic field orient method, adopting the control structure of double closed-loop, taking the motor's speed and the reactive power on the stator side as the control outer race which consist of the control target, and taking the actual current on rotor side which after coordinates transform of current and reference current value to compare. After the voltage which was output by PI modulator and vector quantity anti transform, it can generate trigger pulse that take the modulating signal into SVPWM controller. The double closed-loop control is advantage to the responser speed. It has been validated by simulation that the control strategy is correctness.The whole simulation model comprises nonlinear motor, main circuit and control circuit. The motor model adopt the motor of hysteresis nonlinear which was set up by myself. To assuring the uniformity of semaphore, the model of inverter adopt the basic model with light current interface. The result of simulation has showed the manner is feasible.
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