Small-capacitance power converter and power grid side electric energy quality control working method and bus voltage suppression control method thereof

Abstract

The invention discloses a small-capacitance power converter and a power grid side electric energy quality control working method and a bus voltage suppression control method thereof. The power decoupling circuit is connected in series between a traditional diode rectifier and a direct current bus of a driving system, two energy transmission channels are constructed between a power grid and the direct current bus, and the flexibility of power grid pulsating power processing is remarkably improved. A controller of the active power decoupling circuit is constructed based on a virtual bus voltage concept, instantaneous voltage change of a decoupling capacitor is rapidly and accurately controlled according to working conditions of a driving system, bus voltage pulsation under various working conditions is remarkably reduced, and high-performance operation of the motor driving system under steady-state and dynamic working conditions is realized. Driving system power grid electric energy quality control based on the small-capacitance active power decoupling circuit and direct current bus voltage pulsation suppression are mutually decoupled, the complexity of a system controller is effectively reduced, high-performance operation of a motor is achieved, and meanwhile the power grid electric energy quality related harmonic standard is met.

Description

technical field [0001] The invention belongs to the technical field of power electronics, and relates to a small-capacitance power converter and a power quality control method at the power grid side thereof and a bus voltage suppression control method. Background technique [0002] Permanent magnet synchronous motors have the advantages of simple structure, high power density, and convenient maintenance. They have gradually replaced DC motors and asynchronous motors in the fields of household appliances, industrial production, and automobile drives. In order to achieve high-performance operation of the motor, the DC bus of this type of motor drive system needs to be connected in parallel with a large-value electrolytic capacitor to maintain the stability of the bus voltage. However, short life and poor thermal stability of electrolytic capacitors are the main causes of drive system failures. [0003] The small-capacitance drive system uses small-capacity, high-reliability f...

AI Technical Summary

Problems solved by technology

However, compared with the traditional drive system, the DC bus voltage fluctuation problem of this small capacitor drive system is still prominent, and the motor torque fluctuation problem still exists, especially in dynamic working conditions, which restricts the small capacitor drive system. Application of the system in high-performance applications

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