Motor driving system based on bidirectional interleaved parallel DC-DC inverter

Abstract

The invention discloses a motor driving system based on a bidirectional interleaved DC-DC inverter. According to the system, a bus voltage loop is additionally arranged on the basis of a current loopsum. The motor driving system comprises an acquisition module, a voltage loop controller and a direct-current bus voltage regulator, and is characterized in that the bus voltage acquisition module acquires a direct-current bus voltage Uout of a permanent magnet synchronous motor; the voltage loop controller extracts a rotating speed acquisition value of the permanent magnet synchronous motor froma speed loop, subtracts the rotating speed acquisition value from a given rotating speed, and inputs a difference value into a voltage control model; the voltage control model generates a bus voltagecontrol target Uref by taking the minimum total harmonic distortion rate THD as a target, and outputs the bus voltage control target Uref to the direct-current bus voltage regulator; the direct-current bus voltage regulator generates control signals of four switching devices in an inverter by taking the difference value of Uref and Uout as 0 as a control target; and the inverter generates dynamically regulated bus voltage and applies the bus voltage to a power driving module to drive the permanent magnet synchronous motor. According to the invention, the current ripple torque can be reduced, and the precision and stability of low-speed operation of the motor are improved.

Description

technical field [0001] The invention relates to the field of power electronics technology and the field of permanent magnet synchronous motor control, in particular to a motor drive system based on bidirectional interleaved parallel DC-DC inverters. Background technique [0002] In recent years, with the continuous improvement of power electronics technology, modern control theory, microprocessor technology and permanent magnet material performance, the application of AC permanent magnet synchronous motor (PMSM) has become more and more widespread. Permanent magnet synchronous motors have the characteristics of high power density, high efficiency, low loss, and simple structure, and are widely used in high-precision fields such as industrial automation and robots. [0003] Due to the complex operating conditions of the permanent magnet synchronous motor, its speed may fluctuate in a wide range, and during the operation of the permanent magnet synchronous motor, because the D...

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Problems solved by technology

[0004] The traditional permanent magnet synchronous motor drive system adopts the drive mode of fixed DC bus voltage. When running at low speed and light load, due to the small modulation degree of the inverter, the on-off time and dead time during the switching period have a greater impact on the PWM output waveform. It is bigger at high speed, and it is easy to reflect problems such as large torque ripple and large motor current ripple, which affect the accuracy and stability of the output of the drive system

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