Direct characteristic control based novel double-fed induction motor control method

Abstract

The invention provides a direct characteristic control based novel double-fed induction motor control technology, comprising the following steps: 1, giving a voltage equation with regards to the alpha axis and beta axis of a stator of a double-fed induction motor under a stationary frame; 2, based on the voltage equation given in the step 1 and with the currents of the alpha axis and beta axis of the stator and flux linkages of the alpha axis and beta axis of a rotor as state variables, putting forward a corresponding state equation observer; 3, designing a sliding mode variable structure observer based on the step 2 so as to observe the currents of the alpha axis and beta axis of the stator and the flux linkages of the alpha axis and beta axis of the rotor at the current state; 4, carrying out discretization based on the state equation put forward in the step 2, thus obtaining a prediction control equation, namely predicting the currents of the alpha axis and beta axis of the stator and the flux linkages of the alpha axis and beta axis of the rotor at next time; and 5, using the predicted currents of the alpha axis and beta axis of the stator and currents of the d axis and q axis of the stator, calculated according to a given torque and a given rotor flux linkage together to solve a characteristic equation to obtain the voltages of the alpha axis and beta axis of the stator and sending the voltages to SVPWM. The direct characteristic control based novel double-fed induction motor control technology can be applied to the field of wind power generation and the like.

Description

technical field [0001] The invention relates to a novel doubly-fed induction motor control method based on direct characteristic control, which is suitable for wind power generation systems and other fields where AC motors, especially doubly-fed induction motors, are the control core. Background technique [0002] At present, in wind power generation and other fields, most of the control strategies for doubly-fed induction motors are still based on vector control, and the core of vector control is the three-loop structure, that is, the outer ring of speed, the outer ring of rotor flux linkage and the stator current In the inner loop, it is inevitable to use a PI regulator. However, the PI regulator also has some problems of its own, such as insufficient bandwidth, easy saturation, and so on. Aiming at these problems, some restraining methods and means have been proposed, but the system and structure are undoubtedly more complicated in terms of the whole control method. Ther...

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Problems solved by technology

[0004] The purpose of the present invention is to provide a new doubly-fed induction motor control method based on direct characteristic control, so that the motor can be controlled based on modern control theory in addition to traditional vector control, not only can quickly improve the response speed, but also can Avoid a series of problems such as difficulty in parameter adjustment caused by the use of PI in multiple places in traditional control

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