Control method for single-phase brushless motor

Abstract

The invention discloses a control method for a single-phase brushless motor. The brushless motor with the application of the control method is used in an electric tool, and the electric tool includesa position sensor, a driving circuit, and a controller. The control method includes the steps that: the controller closes a currently outputted control signal when a position signal outputted by the position sensor is changed, after a non-conduction angle T is delayed, the controller triggers the output of a target control signal to the driving circuit, and the driving circuit drives the single-phase brushless motor according to the target control signal. According to the control method, with the change of the position signal outputted by the position sensor as a command, the controller closesthe currently outputted control signal, after the non-conduction angle T, the output of the target control signal to the driving circuit is triggered to drive the single-phase brushless motor so as to reduce the current spikes in the single-phase brushless motor, the overall performance of the single-phase brushless motor is improved, and the size of an electric tool motor and the size of a corresponding control board are reduced.

Description

technical field [0001] Embodiments of the present invention relate to the technical field of motor control, in particular to a method for controlling a single-phase brushless motor. Background technique [0002] In recent years, with the development of permanent magnet new materials, microelectronics technology, automatic control technology and power electronics technology, especially high-power switching devices, brushless motors have made great progress. Single-phase brushless motors are widely used in electric tools, fans, vacuum cleaners and other fields due to their minimum number of phases, relatively simple electrical system, and low cost of drive control circuits. However, there are relatively few applications of single-phase brushless DC motors in the market due to their lower operating efficiency compared to three-phase brushless DC motors. [0003] In the motor, during the conduction period, when the motor rotor rotates to a certain position, the back EMF reaches...

AI Technical Summary

Problems solved by technology

Under the same application, the single-phase brushless motor has more serious armature reaction than the three-phase brushless motor, and the back EMF waveform drops sharply in the later stage of the conduction region, which will cause extremely high current peaks and serious distortion of the current waveform , the overall performance is poor

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