Scientific and Technical Journal

ELECTROTECHNIC AND COMPUTER SYSTEMS

ISSN Print 2221-3937
ISSN Online 2221-3805
EVALUATION OF THE ELECTROMAGNETIC TIME-CONSTANT OF SCIM ROTOR AND ITS INFLUENCE ON VFD DYNAMIC CHARACTERISTICS
Abstract:
In hoisting mechanisms equipped with VFD-fed three-phase squirrel-cage induction motor (SQIM), slow response of the drive during starting is observed; such delay in response negatively impacts the operator. This paper presents an explanation of the reasons of the delay in the motor torque growth at starting based on experimental results and analysis. The effect of inertness, determined by the electromagnetic time-constant of the motor rotor is analyzed. In literature, the evaluation of the electromagnetic time-constant of the SCIM rotor is limited to 6-pole motor. However, in this paper, simplified analytical relationships, linking the rotor electromagnetic time-constant of a SQIM with the motor power and number of poles (for p=4-10), are obtained on experimental basis. A comparison of VFD starting with a preliminary magnetized/demagnetized motor is performed; a significant decrease in the delay growth of the motor torque with preliminary magnetization is shown. Based on the implementation of the functions of modern VFDs, the process of smooth backlash taking-up in the kinematic transmission for slewing mechanism of a portal crane is presented.
Authors:
Keywords
DOI
References
  1. Albatros portal cranes 10/20 t, User manual. (1979) [Instrukciya po ekspluatacii portalnyh kranov “Albatros” gruzopodjemnostju 10/20 t], CRIA Morflot,  M. 124 p.
  2. Sokol portal cranes 16/20/32 t, User manual. (1979) [Instrukciya po ekspluatacii portalnyh kranov “Sokol” gruzopodjemnostju 16/20/32 t], CRIA Morflot, M. 148 p.
  3. Condor portal cranes, User manual. Morflot, (1986) [Instrukciya po ekspluatacii portalnyh kranov “Kondor” postroyki 1974─1984]: V/O “Mortehinforeklama”, M. 140 p.
  4. Radimov, S. N., Anichenko, K. A., “Potential of energy saving of electric drives of portal hoisting machines”, [Potentsial energosberejeniya electroprivodov portalnih gruzopodjemnih mashin] Kiev, Electrical machinery and electrical equipment, Technika, vol. 66, pp. 322─323.
  5. Akimov, L. V., Kotliyarov, V. O., Litvinenko, D. G., (2011) “Dynamic parameters of VFD induction motors”, [Dinamicheskie parametric asinhronnih dvigateley chastotno-reguliruemih electroprivodov], Electrical Engineering and Electromechanics, Kharkiv, vol. 3, pp. 10─14.
  6. Variable speed drives Altivar 71. Programming manual, Schneider Electric, 2006. 238 p.
  7. Variable speed drives Altivar 71. Programming manual, Schneider Electric, 2007. 288 p.
  8. Teplyakov, A. G.,(2002) “Implementation of optimum control of the slewing mechanism electric drive”, [Realizaciya optimalnogo upravleniya electroprivodom mehanizma povorota]Technica, Kiev, Electrical machinery and electrical equipment, vol. 58, pp. 34─38.
  9. Gerasimyak, R. P., Naydenko, E. V.  (2008) “Control of induction motor drives of the slewing mechanisms with reduced dynamic loads”, [Upravlenie asinhronnim electroprivodom mehanizmov povorota, obespechivauschee snizhenie dinamicheskih nagruzok] NTU “KPI” Kharkiv Theory and practice, vol. 30,  pp.111─112.
  10. Gerasimyak, R. P., Subbotin, V. V. (2013) “Improving the quality of transient processes of taking-up the gap in electromechanical systems”, [Uluchshenie kachestva perehodnih processov pri vibore zazora v electromehanicheskih sistemah], Technica, Electrotechnics and computer systems, vol. 10, pp. 27─32.
  11. Kluchev, V. I., (1971) “Limitation of dynamic loads of the electric drive”, , [Ogranichenie dinamicheskih nagruzok electroprivoda] Energy, Moscow.  320 p.
  12. Variable speed drives, Altivar Process ATV900. Catalogue, Schneider Electric, October 2016.78 p.
Published:
Last download:
2017-09-26 16:42:34

[ © KarelWintersky ] [ All articles ] [ All authors ]
[ © Odessa National Polytechnic University, 2014. Any use of information from the site is possible only under the condition that the source link! ]
Яндекс.Метрика