Frequency conversion drive control system and control method based on electrolytic capacitor inverter

Abstract

The invention discloses a frequency conversion driving control system and method based on an electrolysis-free capacitive inverter. The method comprises the following steps: detecting system input voltage current, bus voltage, motor phase current and rotating speed; carrying out Clark and Park conversion on three-phase current to obtain d and q axis current; carrying out error adjustment on a given rotating speed and an actual rotating speed; calculating q axis given current according to input voltage current, speed ring output and capacitance; calculating d axis given current according to voltage; calculating d and q axis error current and carrying out PI adjustment to obtain d and q axis actual voltage; limiting amplitude of actual voltage to obtain d and q axis calculated voltage; carrying out error adjustment on the actual voltage and the calculated voltage and taking the result as current ring feedback; carrying out Park inverse conversion on the d and q axis calculated voltage to obtain alpha and beta axis voltage; and modulating the inverter to control a motor. By the frequency conversion driving control system and method based on the electrolysis-free capacitive inverter, the motor can run at high speed in a flux weakening region, a network side high power factor is obtained, a control structure is simplified, and the reliability of the system is improved.

Description

technical field [0001] The invention belongs to the technical field of AC variable frequency drive, and more specifically relates to an AC variable frequency drive control method based on an electrolytic capacitor inverter. Background technique [0002] Permanent magnet synchronous motors show advantages in the field of speed regulation due to their high efficiency, small size, easy control, remarkable long life and reliability. Many fields such as locomotive traction, electric vehicles and household appliances have been widely used, and have become research hotspots of scholars from all over the world. [0003] Household appliances such as air conditioners, whose input voltage is single-phase AC, and the pre-stage circuit is a single-phase uncontrolled rectifier bridge, the bus voltage is prone to fluctuations, causing harmonic pollution and power factor drop. my country's 3C certification and European CE certification have clear regulations on the current harmonics of hou...

AI Technical Summary

Problems solved by technology

[0004] At present, the commonly used power factor correction schemes for household appliances mostly adopt BOOST circuit topology. Because the circuit contains power devices, switching losses are introduced, and the control circuit is relatively complicated.

At the same time, the large-capacity DC bus capacitor in the circuit is greatly affected by temperature, has a limited service life and low system reliability

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