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Method for diagnostics of synchronous generator defects by changes of external electromagnetic field

Yu.B. Kazakov, A.N. Morozov, A.P. Okeansky, E.A. Shumilov

Vestnik IGEU, 2019 issue 1, pp. 55—61

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Abstract in English: 

Background. Timely diagnostics of synchronous generator (SG) performance reduces the damage to power plants from their failures. Electromagnetic processes in the elements of SG create external electromagnetic fields (EEMF) of SG. Therefore, damage to the SG will cause a change in EEMF. There are systems for registering EEMF of SG, their changes, but there are no mathematical models simulating EEMF changes when SG elements are damaged. The aim of the work is to find mathematically grounded interrelationships between SG defects and EEMF changes.

Materials and methods. The finite element method is used. Model analysis of EEMF of 538 kW SG is done for idle mode, active, inductive and capacitive loads with defects in the field winding, armature winding, taking into account the damping action of the case at a synchronous rotor speed.

Results. A method has been developed for diagnosing SG defects by analyzing the results of finite-element simulation of EEMF and their changes. The greatest change in EEMF when the field winding is damaged has been found to occur with active-inductive load: at a 25 % inter-winding fault of the field coil of one pole, the induction over the neighboring poles increases by 90 %; at a 50 % fault by 235,6 %; at a 75% fault – by 416 %. The break of the parallel branch of the armature winding leads to different amplitude EEMF induction distributions over time on the SG case. The measurements of the EEMF of a working healthy SG have confirmed EEMF presence. Defects of SG elements cause changes in EEMF. Damage to the pole field coil leads to an increase in the EEMF induction in the region of other poles. The defect of the armature winding can be detected by the difference between the amplitudes of the EEMF induction distributions over time at different points on the case. A method for diagnosing damage to the elements of SG by measuring changes in EEMF has been proposed.

Conclusions. The proposed method of synchronous generator defect diagnostics allows determining the types and degree of synchronous generator stator and armature winding damage by changes in the external electromagnetic field.

 

References in English: 

1. Lazarev, G.B., Samorodov, Yu.N. Avariynost' generatorov i sinkhronnykh elektrodvigateley. Novye problemy [Failure rate in generators and synchronous electric drives. New issues]. Sbornik dokladov nauchno-tekhnicheskoy konferentsii «Aktual'nye voprosy i perspektivy razvitiya elektromashinostroeniya» [Proceedings of the scientific and technical conference «Modern issues and prospects for development in electric machine industry»]. Moscow: OAO «VNIIKP», 2015, pp. 35–42.

2. Samorodov, Yu.N. Turbogeneratory. Avarii i intsidenty [Turbogenerators. Accidents and incidents]. Moscow: Eleks-KM, 2008. 488 p.

3. Glebov, I.A., Danilevich, Ya.B. Diagnostika turbogeneratorov [Diagnostics of turbogenerators]. AN SSSR. VNIIElektromashinostroeniya [Academy of Sciences of the USSR. All-Union Research and Development Institution of Electric Machine Industry]. Leningrad: Nauka, 1989. 118 p.

4. Alekseev, B.A. Opredelenie sostoyaniy (diagnostika) krupnykh turbogeneratorov: Obzor otechestvennogo i zarubezhnogo opyta [Determination (diagnostics) of large turbogenerators conditions: A review of the Russian and foreign experience]. Moscow: Izdatel'stvo NTs ENAS, 2001. 152 p.

5. Kazakov, Yu.B., Shumilov, E.A., Tam'yarov, A.V., Morozov, A.N. Vneshnie elektromagnitnye polya elektrodvigateley i sposoby ikh snizheniya [External electromagnetic fields of electric drives and methods of their reduction]. Ivanovo, 2017. 116 p.

6. Khayrullin, I.Kh., Pashali, D.Yu. Diagnostika elektromekhanicheskikh preobrazovateley po vneshnemu magnitnomu polyu [Diagnostics of electromechanical transducers by external magnetic field]. Vestnik UGATU, 2006, vol. 7, no. 1(14), pp. 165–170.

7. Alekseenko, A.Yu., Brodskiy, O.V., Vede-neev, V.N., Tonkikh, V.G., Khomutov, S.O. Diagnostika i prognozirovanie sostoyaniya asinkhronnykh dvigateley na osnove ispol'zovaniya parametrov ikh vneshnego elektromagnitnogo polya [Diagnostics and prediction of induction motor conditions based on the parameters of their external electromagnetic field]. VESTNIK AltGTU im. I.I. Polzunova, 2006, no. 2, pp. 9–13.

8. Novoselov, E.M., Savel'ev, V.A., Skorobogatov, A.A., Strakhov, A.S., Sulynenkov, I.N. Otsenka vozmozhnosti ispol'zovaniya radial'noy sostavlyayushchey vneshnego magnitnogo polya v tselyakh diagnostiki asinkhronnykh elektrodvigateley [Estimation of the possibility of using the radial component of external magnetic field for induction motor diagnostics]. Vestnik IGEU, 2018, issue 3, pp. 38–46.

9. Polishchuk, V.I., Vasil'eva, Yu.Z. Razrabotka sposoba vyyavleniya vitkovogo zamykaniya v obmotke vozbuzhdeniya sinkhronnoy mashiny [Development of the method of localizing inter-winding faults in field coils of induction motors]. Nauchnoe obozrenie, 2014, no. 12, pp. 55–59.

10. Yaghobi, H., Ansari, K., Mashhadi, H. Rajabi. Analysis of Magnetic Flux Linkage Distribution in Salient-Pole Synchronous Generator with Different Kinds of Inter-Turn Winding Faults. Iranian Journal of Electrical & Electronic Engineering, 2011, vol. 7, no. 4, pp. 260–272.

11. Kazakov, Yu.B., Morozov, A.N., Okeanskiy A.P. Diagnostika elektromagnitnykh nesimmetriy po vneshnemu polyu elektricheskikh mashin [Diagnostics of electromagnetic unbalance by measuring the external fields of electric motors]. Materialy V Vserossiyskoy nauchno-tekhnicheskoy konferentsii «Problemy elektrotekhniki, elektroenergetiki i elektrotekhnologiy» (PEEE-2017) [Proceedings of the V All-Russia scientific and technical conference «Problems of electric engineering, electric power engineering and electric technologies»]. Tol'yatti: Izdatel'stvo TGU, 2017, pp. 376–380.

 

Key words in Russian: 
синхронные генераторы, дефекты обмотки возбуждения, обмотка якоря, диагностика синхронных генераторов, внешние электромагнитные поля, конечно-элементное моделирование
Key words in English: 
synchronous generators, field coil defects, armature winding, diagnostics of synchronous generators, external electromagnetic fields, finite element simulation
The DOI index: 
10.17588/2072-2672.2019.1.055-061
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25