DC bus voltage control brushless motor commutation method

Abstract

The invention discloses a DC bus voltage control brushless motor commutation method. The method is characterized in that a compensation voltage is calculated according to a differential equation, at a motor non-commutation stage, a capacitor is charged according to the compensation voltage; at a motor commutation stage, the capacitor is connected in series with a power source to supply power for the motor to enhance the bus voltage. At the commutation period, the motor is provided with energy by the capacitor, the capacitor voltage decreases, after commutation, the bus voltage Udc is just kept at the level of 4E+3IR, the E is back electromotive force, the I is an average phase current value, the R is motor winding resistance, at the whole commutation stage, the motor stays in a low speed running state, a traditional PWM method is utilized to modulate an inverter, and commutation torque ripple is effectively inhibited. The method is advantaged in that the control strategy at the whole commutation stage same as at the normal motor conduction stage is utilized to control the inverter, controller design is simplified, system stability is improved, and excellent engineering application prospects are realized.

Description

technical field [0001] The invention belongs to the field of brushless direct current motor control, and in particular relates to a brushless motor commutation method controlled by direct current bus voltage. Background technique [0002] The motor is an electromagnetic device that converts mechanical energy and electrical energy through the medium of a magnetic field. The motor industry is a traditional industry. After years of development, it has become an indispensable core and foundation in modern production and life, and an important part of the national economy. With the continuous improvement of production modernization and the continuous increase of people's consumption of household appliances and automobiles, the market demand for motors is also increasing. Motors are mainly divided into three types: synchronous motors, asynchronous motors and DC motors, and their capacities range from a few watts to tens of thousands of watts. Different motors have different appl...

AI Technical Summary

Problems solved by technology

However, the commutation torque ripple severely limits its application range

According to literature research, when the brushless DC motor is running at high speed, if the motor winding resistance is ignored, when the bus voltage is less than 4 times the back electromotive force, the power switch of the inverter cannot be suppressed by modulating the commutation torque ripple

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