A control method of asynchronous motor without speed sensor drive

Abstract

The invention discloses a control method of an asynchronous motor driven by a speed sensor, which belongs to the technical field of motors. The invention adjusts the input voltage amplitude and phase of the flux linkage and rotational speed observer adaptively through the voltage switching structure, so that the input voltage of the flux linkage and rotational speed observer is a virtual voltage at low speed, and ensures the asynchronous speed under the drive of the speed sensorless control system. Stable and reliable operation of the motor at low speeds; the input voltage of the flux linkage and speed observer is close to the actual voltage at high speeds, ensuring the speed control accuracy of the asynchronous motor driven by the speed sensorless control system at medium and high speeds; The motor flux orientation angle is estimated, and the vector control method is used to drive the asynchronous motor to run normally, so that the actual flux current, actual torque current, and estimated motor speed of the motor are respectively related to the reference flux current, reference torque current, and motor reference speed. Consistent, the smooth switching between the virtual voltage and the actual reference voltage is realized.

Description

technical field [0001] The invention belongs to the technical field of motors, and more specifically relates to a control method for an asynchronous motor driven by a speed sensor. Background technique [0002] As an important part of the equipment manufacturing industry, induction motors (including single-phase, three-phase and multi-phase induction motors) and their drive inverters (including low-voltage, medium-voltage and high-voltage inverters) are widely used in various industries of the national economy . The high reliability of induction motors is the main reason for its wide application. Therefore, in most application fields of induction motors, speed sensors such as encoders and resolvers, which are expensive and unreliable, will be abandoned, and speed sensorless drive technology will be used. The control method of asynchronous motor driven by speed sensor is of great significance. [0003] The rotor speed of an asynchronous motor at zero synchronous speed is un...

AI Technical Summary

Problems solved by technology

[0005] In view of the above defects or improvement needs of the prior art, the present invention provides a speed sensorless drive asynchronous motor control method, the purpose of which is to solve the existing fixed coefficient virtual voltage injection technology due to the difference between the observer input voltage and the motor. The actual voltage is different, resulting in the technical problem of insufficient rotor speed control accuracy when the motor is running at medium and high speeds

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