Title :
Parallel operation of digital controlled UPS system
Author :
Tamai, Shinzo ; Kinoshita, Masahiro
Author_Institution :
Mitsubishi Electric Corp., Hyogo, Japan
fDate :
28 Oct-1 Nov 1991
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;
Conference_Titel :
Industrial Electronics, Control and Instrumentation, 1991. Proceedings. IECON '91., 1991 International Conference on
Conference_Location :
Kobe
Print_ISBN :
0-87942-688-8
DOI :
10.1109/IECON.1991.239362
