Control system for a PWM-based STATCOM

Author

Garica-Gonzalez, P. ; García-Cerrada, Aurelio

Author_Institution

ETS de Ingenieria, Univ. Pontificia Comillas de Madrid, Spain

Volume

15

Issue

4

fYear

2000

fDate

10/1/2000 12:00:00 AM

Firstpage

1252

Lastpage

1257

Abstract

The always-increasing switching frequency of modern solid-state power switches, together with the application of multi-converter topologies, make it possible to use pulse width modulation (PWM) in high power applications of STATCOMs (static synchronous compensators). This paper investigates the control system for a PWM-based STATCOM. First of all, a discrete-time model of the STATCOM is derived to take into account the discrete-time implementation of the controller. Secondly, the control algorithm is detailed. It ensures decoupled control of the real and reactive power exchanged between the power converter and the electric-energy system. This is necessary to control the DC capacitor voltage during transients of the exchanged reactive power. Finally, the control of the capacitor voltage is explained in detail. The controller is tailored to keep the capacitor voltage almost constant in spite of the fast control of the reactive power. This helps to reduce the capacitor size significantly. The main contributions are illustrated using a 15 kVA laboratory prototype

Keywords

PWM power convertors; reactive power control; static VAr compensators; voltage control; 15 kVA; DC capacitor voltage control; PWM power converter; PWM-based STATCOM; control algorithm; control system; decoupled control; discrete-time model; electric-energy system; multi-converter topologies; reactive power exchange; real power exchange; solid-state power switches; static VAr compensators; static synchronous compensators; switching frequency; Automatic voltage control; Capacitors; Control systems; Pulse width modulation; Reactive power control; Solid state circuits; Space vector pulse width modulation; Switching frequency; Topology; Voltage control;

fLanguage

English

Journal_Title

Power Delivery, IEEE Transactions on

Publisher

ieee

ISSN

0885-8977

Type

jour

DOI

10.1109/61.891511

Filename

891511