Title: Characteristics of modern nonlinear loads and their influence on systems with distributed generation

Authors: Doron Shmilovitz, Jiwu Duan, Dariusz Czarkowski, Zivan Zabar, Serena Lee

Addresses: School of Electrical Engineering, Tel Aviv University, Ramat Aviv, Tel Aviv 69978, Israel. ' Department of Electrical and Computer Engineering, Polytechnic University, Brooklyn, NY 11201, USA. ' Department of Electrical and Computer Engineering, Polytechnic University, Brooklyn, NY 11201, USA. ' Department of Electrical and Computer Engineering, Polytechnic University, Brooklyn, NY 11201, USA. ' Consolidated Edison Company of New York, Inc., 4 Irving Pl., New York, NY 10003, USA

Abstract: Nonlinear electronic loads may demonstrate unexpected reactions to variations in power system voltage. This effect of the electrical load may be very significant in distributed generation power systems containing relatively small generators. This paper reviews modern nonlinear electronic load current consumption mechanisms and provides typical current waveforms. Based on extensive measurements and field surveys, modified ZIP models have been developed to produce descriptive behaviour for a large class of nonlinear loads that account for cutoff voltages. Finally, an independent PC program was developed to analyse individual load equipment under varying voltage conditions based on the active and reactive powers at the rated voltage. The program also enables the study of combined loads (such as in a single residential or commercial building).

Keywords: harmonics; load estimation; ZIP model; varying voltage; reactive power; power quality; nonlinear loads; distributed generation; power generation; power electronics; waveforms; combined loads.

DOI: 10.1504/IJETP.2007.013033

International Journal of Energy Technology and Policy, 2007 Vol.5 No.2, pp.219 - 240

Published online: 04 Apr 2007 *

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