Brushless motor current regulator, motor system and control method

Abstract

A regulator for controlling the current of a brushless motor, comprising a current sensing circuit for sensing a phase current of a motor to generate a current sensing signal; a current reference generating circuit for generating a current reference signal, the current reference signal Contains target current information; reset signal comparison circuit, used to compare the current sensing signal with the current reference signal, and generate a switch reset signal; motor switch signal generator, used to set the motor switch signal and the motor switch signal according to the switch reset signal Makes the absolute magnitude of the motor phase currents follow the current reference signal. The motor current regulator can make the overall waveform of the motor phase current follow the current reference signal by comparing the current sensing signal and the current reference signal, so that the motor phase current is in a fully controlled state.

Description

technical field [0001] The invention relates to an electronic circuit, in particular to a brushless motor current regulator, a motor system and a control method. Background technique [0002] With the development of industrial technology, single-phase brushless DC motor systems are widely used in various industrial and consumer fields. E.g, figure 1 A schematic circuit diagram of a typical single-phase brushless DC motor system 100 in the prior art is given. Such as figure 1 As shown, the single-phase brushless DC motor system 100 includes a Hall commutation detector 101, has a Hall sensor 1011 and a Hall comparator 1012, and outputs a commutation signal V PHASE , a PWM (Pulse Width Modulation) signal generator 102 outputs a PWM motor switch signal V with a fixed duty cycle PWM . The logic drive circuit 103 receives the commutation signal V PHASE and the PWM signal V PWM , generating a set of switch driving signals S1-S4 to control the driving bridge 104 . The H-type...

AI Technical Summary

Problems solved by technology

[0003] Output phase current I COIL In a rotor cycle, there are often problems such as commutation phase difference and current spikes.

At the same time, due to the phase current I COIL controlled by the phase voltage V COIL1 (SW1 and SW2 common point voltage) and V COIL2 (SW3 and SW4 common point voltage), rotor reaction electromotive force, motor inductance and other factors, different motors have different magnetization control and motor winding inductance, and fluctuations in power supply voltage will cause output consistency problems

Designing compensation for these problems is very complicated to implement, and often requires dedicated digital operation circuits (such as microcontroller MCU, digital signal processor DSP, etc.) to achieve, which increases the cost and the effect is still not good

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