Emergency Generator Sizing and Motor Starting Analysis

Authors: Mukesh Kumar Kirar, Ganga Agnihotri

Abstract:

This paper investigates the preliminary sizing of generator set to design electrical system at the early phase of a project, dynamic behavior of generator-unit, as well as induction motors, during start-up of the induction motor drives fed from emergency generator unit. The information in this paper simplifies generator set selection and eliminates common errors in selection. It covers load estimation, step loading capacity test, transient analysis for the emergency generator set. The dynamic behavior of the generator-unit, power, power factor, voltage, during Direct-on-Line start-up of the induction motor drives fed from stand alone gene-set is also discussed. It is important to ensure that plant generators operate safely and consistently, power system studies are required at the planning and conceptual design stage of the project. The most widely recognized and studied effect of motor starting is the voltage dip that is experienced throughout an industrial power system as the direct online result of starting large motors. Generator step loading capability and transient voltage dip during starting of largest motor is ensured with the help of Electrical Transient Analyzer Program (ETAP).

Keywords: Sizing, induction motor starting, load estimation, Transient Analyzer Program (ETAP).

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1088774

References:

[1] IEEE Recommended Practice for Industrial and Commercial Power Systems Analysis, IEEE Std 399-1997 , vol., no., pp.I, 1998
[2] IEC 60034-12:1980, “Rotating electrical machines” Part 12: Starting performance of single speed three-phase cage induction motors for voltages up to and including 660 V
[3] Rotating electrical machines – Part 1: Rating and performance, IEC 60034-1, 1999-08.
[4] IEEE Recommended Practice for Protection and Coordination of Industrial and Commercial Power Systems," ANSI/IEEE Std 242-1986 , vol., no., pp.0_1, 1986.
[5] A. Jack Williams, M. Shan Griffith, "Evaluating the Effects of Motor Starting on Industrial and Commercial Power Systems," Industry Applications, IEEE Transactions on, vol.IA-14, no.4, pp.292-305, July 1978.
[6] P.S. Patil, K.B. Porate, "Starting Analysis of Induction Motor: A Computer Simulation by ETAP Power Station," Emerging Trends in Engineering and Technology (ICETET), 2009 2nd International Conference on , vol., no., pp.494-499, 16-18 Dec. 2009
[7] IEEE Recommended Practice for Electric Power Distribution for Industrial Plants” IEEE Std 141-1993.
[8] Liang Xiaodong, O. Ilochonwu, "Induction Motor Starting in Practical Industrial Applications," Industry Applications, IEEE Transactions on , vol.47, no.1, pp.271-280, Jan.-Feb. 2011
[9] John H. Stout “Capacitor Starting Of Large Motors ” IEEE Transactions On Industry Applications, Vol. Ia-14, No. 3, May/June 1978, pp. 209- 212
[10] A. Jack Williams, JR. Member, M. Shan Griffith, “Evaluating the Effects of Motor Starting on Industrial and Commercial Power Systems” IEEE Transactions On Industry Applications, Vol. IA-14, NO. 4, JULY/AUGUST 1978