Driving method for position-sensorless of permanent magnet brushless direct current motor

Abstract

The invention discloses a driving method for a position-sensorless of a permanent magnet brushless direct current motor, is applied to the permanent magnet brushless direct current motor under a high-speed and heavy-load condition, and belongs to the field of permanent magnet brushless direct current motor controlling. By utilizing the characteristic that the current slop of a follow current phase is a monotone function, by setting a corresponding threshold value, the counter potential of the follow current phase can still be detected when zero crossing point is submerged. The driving method for the position-sensorless of the permanent magnet brushless direct current motor is matched with a traditional counter potential zero crossing point method, the application range of sensorless technology of the permanent magnet brushless direct current motor can be enlarged. A central point of a coil does not need to be connected out, the requirement for the counter potential waveform of the motor is low, and the adaptability is high.

Description

technical field [0001] The invention belongs to the technical field of brushless direct current motor control methods, relates to a brushless direct current motor without a position sensor technology, in particular to a permanent magnet brushless direct current motor without a position sensor driving method. Background technique [0002] Permanent magnet brushless DC motors (BLDC motors for short) have simple control methods, high power density, and high efficiency, and are widely used in high-speed electric drive applications. As an important research direction of BLDC motor, position sensorless technology eliminates the position sensor of the motor, reduces the axial length of the motor, reduces the constraints of the motor design, and improves the reliability of the system. [0003] Judging the rotor position based on the back EMF zero crossing point is one of the most widely used position sensorless solutions for BLDC motors. [0004] This method is mainly divided into ...

AI Technical Summary

Problems solved by technology

However, this method requires that the opposite potential of the motor contains a large third harmonic, and the center point of the winding needs to be drawn out, which not only requires high electromagnetic design requirements for the motor, but also is not conducive to the machining of the motor.

Images