Author : Alphy Maria Abraham 1
Date of Publication :7th June 2015
Abstract: Induction motors are the most commonly used machine in industry because of their robust nature. Energy management of induction motor is relevant as they form the bulk segment in industry. So online monitoring and efficiency estimation of the existing induction motors play a vital role in energy management. The air gap torque (AGT) method is a well established technique for determining the efficiency of an induction motor, since it is known to be highly accurate Unlike testing motor efficiency in a laboratory, certain methods given in IEEE Standard 112 cannot be used for motor efficiency evaluations in the field. For example, it is difficult to load a motor in the field with a dynamometer when the motor is already coupled to driven equipment. The motor efficiency field evaluation faces a different environment from that for which IEEE Standard 112 is chiefly written. A field evaluation method consists of one or several basic methods. This paper separates and compares the basic methods according to their physical natures.
- J. D. Kueck, M. Olszewski, D. A. Casada, J. S. Hsu, P. J. Otaduy, and L. M. Tolbert, ―Assessment of methods for estimating motor efficiency and load under field conditions,‖ Lockheed Martin Energy Research Corp., Oak Ridge, TN, Rep. ORNL/TM-13165, Jan. 1996.
- J. S. Hsu and P. L. Sorenson, ―Field assessment of induction motor efficiency through air-gap torque,‖ IEEE Trans. Energy Conversion, vol. 11, pp. 489–494, Sept. 1996.
- High Efficiency Motor Selection Handbook, Bonneville Power Administration (BPA), Portland, OR, 1990, p. 21.
- W. D. Biesemeyer and J. Jowett, ―Facts and fiction of HVAC motor measuring for energy savings,‖ Arizona Department of Commerce, Energy Office, Phoenix, AZ, Biesemeyer #116, 1994
- P. L. Alger, The Nature of Induction Machines. New York: Gordon and Breach, 1965.
- J. S. Hsu, H. H. Woodson, and W. F. Weldon, ―Possible errors in measurement of air-gap torque pulsations of induction motors,‖ IEEE Trans. Energy Conversion, vol. 7, pp. 202–208, Mar. 1992.
- J. S. Hsu, ―Monitoring of defects in induction motors through air-gap torque observation,‖ IEEE Trans. Ind. Applicat., vol. 31, pp. 1016–1021, Sept./Oct. 1995.
- C. L. Becnel et al., ―Determining motor efficiency by field testing,‖ IEEE Trans. Ind. Applicat., vol. IA23, pp. 440–443, May/June 1987.
- A. H. Bonnett, ―An update on ac induction motor efficiency,‖ IEEE Trans. Ind. Applicat., vol. 30, pp. 1362–1372, Sept./Oct. 1994
- IEEE Standard Test Procedure for Polyphase Induction Motors and Generators, IEEE Standard 112- 1991, 1991.
- H. E. Jordan and A. Gattozzi, ―Efficiency Testing of Induction Machines,‖ in Conf. Rec. IEEE-IAS Annu. Meeting, Cleveland, OH, Sept. 30–Oct. 5, 1979, pp. 284–289.
- R. E. Oesterlei, ―Motor efficiency test methods— Apple and oranges?,‖ Power Transmission Design, vol. 22, no. 5, pp. 41–43, May 1980.
- P. G. Cummings, W. D. Bowers, and W. J. Martiny, ―Induction motor efficiency test methods,‖ IEEE Trans. Ind. Applicat., vol. IA-17, pp. 253–272, May/June 1981
- NEMA Standards Publication No. MG1, National Electrical Manufacturers Association (NEMA), Washington, D.C., 1993.
- Motor Master, Version 2.1., 98504-3165.K, Washington State Energy Office, Olympia, WA.
- R. L. Nailen, ―Can field tests prove motor efficiency?,‖ in Conf. Rec. IEEE I&CPS Tech. Conf., Baltimore, MD, May 2–5, 1988, pp. 110–116.
- J. S. Hsu, P. J. Otaduy, and J. D. Kueck, ―Efficiency and reliability assessments of retrofitted high-efficiency motors,‖ in Conf. Rec. IEEEIAS Annu. Meeting, Lake Buena Vista, FL, Oct. 8–12, 1995, pp. 2745–2751.
- J. S. Hsu and B. P. Scoggins, ―Field test of motor efficiency and load changes through air-gap torque,‖ IEEE Trans. Energy Conversion, vol. 10, pp. 471–477, Sept. 1995.
- Understanding AC motor efficiency,‖ Electrical Apparatus Service Association, St. Louis, MO