Title: DSTATCOM topologies for three-phase high power applications

Authors: Vincent George, Mahesh K. Mishra

Addresses: Department of Electrical Engineering, Indian Institute of Technology Madras, Chennai, India. ' Department of Electrical Engineering, Indian Institute of Technology Madras, Chennai, India

Abstract: This paper proposes distribution static compensator topologies for application in three-phase high power distribution systems. These topologies overcome both the voltage and current rating constraints imposed by the semiconductor switches by the use of three single-phase multi-secondary transformers. Five topologies, namely, four leg-group, three leg-group split-capacitor, H bridge-group, three leg-group and two leg-group are suggested. These can effectively compensate unbalance, harmonics and low power factor of the load currents. Apart from the use of minimum number of current sensors and a single capacitor, the control circuit is very simple. It provides the electrical isolation and security deemed essential for high voltage systems. A detailed comparison is made for these topologies. Based on the hardware requirement and compensation quality, the four leg-group and three leg-group topologies are shown to be superior than the other structures for application in three phase four-wire and three-wire systems respectively. They are validated through extensive simulation studies using PSCAD in a three-phase four-wire power network with non-linear unbalanced load. Experimental verification is conducted for H bridge-group topology on a single phase system using a DSP-based prototype laboratory model.

Keywords: active power filters; distribution static compensators; DSTATCOM; instantaneous symmetrical component theory; high power transformers; multiple winding transformers; unbalance; harmonics; low power; electrical isolation; security.

DOI: 10.1504/IJPELEC.2010.031189

International Journal of Power Electronics, 2010 Vol.2 No.2, pp.107 - 124

Received: 08 Apr 2008
Accepted: 21 Jan 2009
Published online: 25 Jan 2010 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article