A Novel Control Method of Brushless DC Motor Based on Direct Characteristic Control

Abstract

A brushless DC motor control method based on direct characteristic control comprises the following steps of (1) building a three-phase voltage equation of a stator of a brushless DC motor under a three-phase coordinate system; (2) taking three phase currents of the stator and three phase magnetic links of a rotor as state variables according to the voltage equation listed in the step (1), and listing a corresponding state equation observer; (3) observing the three phase currents of the stator and the three phase magnetic links of the rotor in the current state according to a sliding-mode variable structure observer designed in the step (2); (4) carrying out discretization to obtain a forecast control equation according to the state equation in the step (2), namely, forecasting the three phase currents of the stator and the three phase magnetic links of the rotor at a next moment; and (5) carrying out characteristic equation on the three phase currents of the stator, calculated according to the forecasted three phase currents of the stator, the given torque and the given magnetic links of the rotor, to figure out the three phase voltages of the stator, and sending the three phase voltages into space vector pulse width modulation (SVPWM). The brushless DC motor control method can be widely applied to fields such as household appliances, office automation and automotive electronics.

Description

technical field [0001] The invention relates to a novel brushless DC motor control method based on direct characteristic control, which is suitable for fields such as household appliances, office automation, and automotive electronic systems where AC motors, especially brushless DC motors, are the control cores. Background technique [0002] At present, in the fields of household appliances, office automation, and automotive electronics, most of the control strategies for brushless DC motors are still based on vector control, and the core of vector control is the double-loop structure, that is, the outer loop of the speed and the inner loop of the stator current. Ring, it is inevitable to use a PI regulator, but 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 t...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a new type of control method for brushless DC motor 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

Images