Parallel operation of digital controlled UPS system

Author

Tamai, Shinzo ; Kinoshita, Masahiro

Author_Institution

Mitsubishi Electric Corp., Hyogo, Japan

fYear

1991

fDate

28 Oct-1 Nov 1991

Firstpage

326

Abstract

A digital control algorithm for parallel connected three-phase inverters used in a UPS (uninterruptible power supply) is proposed. Each inverter module has an LC filter. The digital voltage controller, which has high-speed current control as a minor loop, provides low voltage distortion even for nonlinear loads. A parallel operation controller supplements the voltage controller in each inverter module. Voltage reference command of each inverter is controlled to balance the load current. It was confirmed by simulation and an experiment that low distortion characteristics of output voltage and good load sharing control characteristics were achieved by this control algorithm

Keywords

digital control; electric current control; invertors; uninterruptible power supplies; voltage control; voltage regulators; LC filter; digital controlled UPS system; digital voltage controller; high-speed current control; inverter module; load sharing control; low voltage distortion; nonlinear loads; parallel connected three-phase inverters; parallel operation controller; simulation; uninterruptible power supply; Capacitors; Control systems; Digital control; Equations; Low voltage; Power harmonic filters; Power system reliability; Pulse width modulation inverters; Uninterruptible power systems; Voltage control;

fLanguage

English

Publisher

ieee

Conference_Titel

Industrial Electronics, Control and Instrumentation, 1991. Proceedings. IECON '91., 1991 International Conference on

Conference_Location

Kobe

Print_ISBN

0-87942-688-8

Type

conf

DOI

10.1109/IECON.1991.239362

Filename

239362