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On the use of selected 4th generation nuclear reactors in marine power plants

Drosińska-Komor Marta, Głuch Jerzy, Breńkacz Łukasz, Ziółkowski Paweł

Polish Maritime Research

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2022

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nr 1

76--84

EN

This article provides a review of the possibility of using different types of reactors to power ships. The analyses were carried out for three different large vessels: a container ship, a liquid gas carrier and a bulk carrier. A novelty of this work is the analysis of the proposal to adapt marine power plants to ecological requirements in shipping by replacing the conventional propulsion system based on internal combustion engines with nuclear propulsion. The subjects of comparison are primarily the dimensions of the most important devices of the nuclear power plant and the preliminary fitness analysis. It was assumed for this purpose that the nuclear power plant fits in the engine room compartment and uses the space left after the removal of the combustion engines. At the same time, this propulsion provides at all times sufficient energy for port, technological and shipping operations at an economically justifiable speed. For deep-sea vessels, which are supposed to reach null emissions of CO, CO2, NOx, SOx and H2O, this is one of the most reasonable solutions. Finally the paper proves that all the above-mentioned marine functions could be effectively applied in power plants equipped with 4th generation nuclear reactors.

2

Failure analysis of a high-speed induction machine driven by a SiC-inverter and operating on a common shaft with a high-speed generator

Breńkacz Łukasz, Bagiński Paweł, Adamowicz Marek, Giziewski Sebastian

Eksploatacja i Niezawodność

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2022

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Vol. 24, no. 1

177--185

EN

Due to ongoing research work, a prototype test rig for testing high speed motors/generators has been developed. Its design is quite unique as the two high speed machines share a single shaft with no support bearings between them. A very high maximum operating speed, up to 80,000 rpm, was required. Because of the need to minimise vibration during operation at very high rotational speeds, rolling bearings were used. To eliminate the influence of higher harmonics of supply voltage and current on the formation of torque oscillations on the shaft and excessive losses in the form of heat, a voltage source inverter with high switching silicon carbide (SiC) power transistors characterizing high precision of the output voltage generation with a fundamental harmonic frequency of several kilohertz has been used. During the first start-ups, it turned out that the system was not stable, and a failure occurred. The paper presents the consequences that may arise when a machine operating at a speed of about 70,000 rpm fails. The article contains pictures of a generator failure that occurred at a high rotational speed.

3

Comparable analysis of PID controller settings in order to ensure reliable operation of active foil bearings

Witanowski Łukasz, Breńkacz Łukasz, Szewczuk-Krypa Natalia, Dorosińska-Komor Marta, Puchalski Bartosz

Eksploatacja i Niezawodność

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2022

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Vol. 24, no. 2

377--385

EN

In comparison to the traditional solutions, active bearings offer great operating flexibility, ensure better operating conditions over a wider range of rotational speeds and are safe to use. In order to ensure optimum bearing performance a bearing control system is used that adapts different geometries during device operation. The selection of optimal controller parameters requires the use of modern optimization methods that make it possible to quickly achieve the assumed parameters. This article presents the method that has been employed to select the parameters of a proportional integral derivative (PID) controller, in which both stochastic algorithms and hybrid methods have been compared. The results show that all of the used algorithms were able to reach the global optimum but only the hybrid algorithm was repeatable in all runs within a low value of the standard deviation. The best solution will be proposed in the future to control an active foil bearing. Analysing of this paper would help to prevent failures of active foil bearing used in the designed rotating machine.

4

Application of the Teager-Kaiser energy operator in diagnostics of a hydrodynamic bearing

Blaut Jędrzej, Breńkacz Łukasz

Eksploatacja i Niezawodność

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2020

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Vol. 22, no. 4

757--765

EN

The paper presents the use of the Teager-Kaiser energy operator (TKEO) to evaluate the state of rotor unbalance. The method was developed in 1990 by Kaiser and involves a simple calculation of signal energy. It has been used before in diagnostics, e.g. during the evaluation of instability of hydrodynamic bearings and as a diagnostic symptom of gearbox damage. This paper is the first to present the use of the Teager-Kaiser method to evaluate the rotor unbalance in hydrodynamic bearings.

PL

W artykule przedstawiono zastosowanie operatora energetycznego Teagera-Kaisera (TKEO) do oceny stanu niewyważenia wirnika. Metoda ta opracowana została w 1990 roku przez Kaisera i polega na prostym obliczeniu energii sygnału. Wykorzystywana była już wcześniej w diagnostyce np. przy ocenie niestabilności łożysk hydrodynamicznych oraz jako symptom diagnostyczny uszkodzenia przekładni. W artykule tym po raz pierwszy przedstawiono możliwość wykorzystania metody Teagera-Kaisera do oceny niewyważenia wirnika pracującego na łożyskach hydrodynamicznych.