JUSTIFICATION OF SAFETY BRAKE PARAMETERS FOR HOISTING MACHINES IN MINES
It is shown that safety brakes of mine hosting machines, given the idle time tх.х
= 0,5 s, and the static reliability factor Kс.н
= 3, ensure maximum permissible deceleration Aдоп = 5 m/s2
, and, thus, minimum deceleration track in neither mine.
Reduction in idle time down to tх.х
= 0,1 s, allowed better deceleration from 10.7 to 53% for small hosting machines and improved deceleration by 7% for large hoisting machine depending on the initial velocity prior to deceleration. The deceleration track is decreased by 14.3–23.7% for small machines and by 10.7–12.9 for large machines in this case under the same conditions.
By simultaneous reduction in the idle time to the value of tх.х
= 0,1 s, and the increase in the static reliability factor Kс.н
enables maximum deceleration Aдоп = 5 m/s2
. The deceleration track becomes shorter by 29.1–50.1% for small machines and by 21.1–25.8 for large machines depending on the initial velocity. However, the studies have shown that the static reliability factor Kс.н
first grows to a value of Kс.н
= 10,5 at the initial velocity Vнач
= 3,45 m/s, and then lowers down to Kс.н
= 4,4 as the initial velocity increases to Vнач
= 11,5 m/s.
For large machines, the static reliability factor Kс.н ranges from Kс.н
= 4,1 at the velocity Vнач
= 13,8 , m/s, to Kс.н
= 3,75 as the initial velocity grows to Vнач
= 18,4 m/s.
The increase Kс.н
entails intense wear of brake shoes and, as a consequence, the loss of their life.
Concurrent mechanical and electrical braking action also allows maximum deceleration Aдоп = 5 m/s2
. In the capacity of an electric brake, the hoisting motor is used in the mode of dynamic deceleration with separate excitation, the maximum force F*т.д.max = 2 is ensured by including auxiliary resistor rotor in the circuit. The minimum deceleration track for small machines is achieved by setting tх.х
= 0,1 s, and the static reliability factor Kс.н
varies from Kс.н
= 7,5 to Kс.н
= 3. For large, machines, tх.х
= 0,5 s, is set, and the static reliability factor Kс.н ranges between Kс.н
= 3,5 and Kс.н
= 3 , which enables reduction in wear of brake shoes at the increased initial velocity and the extended life cycle.
Mine hoisting machine, synchronized action mode, dynamic deceleration, life, shell ring, brake shoe.
Issue number: 3
Authors: Malinovskiy A. K., Shalloev A. P., Sorokina S. A.
About authors: Malinovskiy A.K., Doctor of Technical Sciences, Professor,
Shalloev A.P., Magister,
Sorokina S.A.1, Magister,
Mining Institute, National University of Science and Technology «MISiS»,
119049, Moscow, Russia, e-mail: email@example.com.
REFERENCES: 1. Pivnyak G. G., Shkrabets F. P., Gorbunov Ya. S. Releynaya zashchita elektroustanovok na otkrytykh gornykh rabotakh (Relay protection for electrical devices in surface mining), Moscow, Nedra, 1992, 240 p.
2. Ershov Yu. A., Kiselev D. N. Modelirovanie ustroystv releynoy zashchity v srede MATLAB (Relay protection modelling in Matlab), LAP LAMBERT Academic Publishing, 2012, 148 p.
3. Andreeva A. V., Kiselev D. N. Modelirovanie tsifrovykh organov toka, available at: http://elib.sfu-kras.ru/handle/2311/5331, 2015 (accessed 29.12.2015).
4. Likhachev F. A. Zamykaniya na zemlyu v setyakh s izolirovannoy neytral’yu i s kompensatsiey emkostnykh tokov (Earth fauls in isolated neutral networks with capacitive currents compensation), Moscow, Energiya, 1971, 152 p.
5. Chernykh I. V. Modelirovanie elektrotekhnicheskikh ustroystv v Matlab, SimPowerSystems i Simulink (Electrical devices modelling in Matlab, SimPowerSystems и Simulink), Moscow, DMK Press, 2008, 288 p.
6. Fedoseev A. M. Releynaya zashchita elektroenergeticheskikh sistem (Power system relay protection), Moscow, Energoatomizdat, 1992, 532 p.
7. Ovcharenko N. I. Tsifrovye apparatnye i programmnye elementy mikroprotsessornoy releynoy zashchity i avtomatiki energosistem (Digital hardware and software elements of power system relay protection and automatization), Moscow, NTF Energoprogress, 2006, 120 p.
8. Phadke A. G. Hidden failures in electric power systems. International Journal of Critical Infrastructures, 2004, vol. 1, no 1.
9. Gurevich V. I. Mikroprotsessornye rele zashchity. Ustroystvo, problemy, perspektivy (Microprocessor-based relay protection. Structure, problems, prospects), Moscow, Infra-Inzheneriya, 2011, 336 p.
10. Horowitz S. H., Phadke A. G. Power system relaying Chichester. Research Studies Press Limited, 2008. 332 p.
11. Шнеерсон Э. М. Цифровая релейная защита (Digital relay protection), Moscow, Energoatomizdat, 2007, 549 p.
12. Internet-forum «Sovety byvalogo releyshchika» http://rza.communityhost.ru (accessed 29.12.2015).
13. Terzija V., Valverde G., Deyu Cai. Wide-Area Monitoring, Protection, and Control of Future Electric Power Networks. Proceedings of the IEEE, 2011, Vol. 99, No. 1 pp. 80–93.
14. Emilson P. L. Scientific and Engineering Applications Using MATLAB. Rijeka.: InTech, 2011. 214 p.