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Changing the ship propulsion system performances induced by variation in reaction degree of turbocharger turbine

Ghaemi M.

Journal of Polish CIMAC

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2011

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Vol. 6, no 1

55-70

EN

This paper presents a detailed mathematical model of ship propulsion system including slow speed diesel engine, screw propeller and governor. This mathematical model is then employed to investigate the system performances both in steady state and unsteady states. The simulation results are checked and the model is verified using experimental data. Next an original method for the system sensitivity analysis against changing of parameters is given. This method is finally applied for investigating the influence of degree of reaction of turbine of turbocharger on the system behaviour.

2

Influence of electric power generation structure on frequency control — mathematical modelling

Domachowski Z., Ghaemi M.

Archiwum Energetyki

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2011

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T. 41, nr 3-4

3-14

EN

A 20% decrease in CO2 emission is the principal goal formulated by European Union in the "3x20" package. As a result, development of windfarms, nuclear power plants and even small heat and power generating plants are expected in Poland. Electric power generation in windfarms and in nuclear power plants involves specific problems in the electric grid frequency control. Windfarm power generation requires a support from conventional power plants, when a nuclear power plant requires adequate structure for the control and adjustment purposes. A concept of mathematical model of so-called multi-machine power system, based on representative power plant mathematical models, has been presented in this paper. Such a model of electric grid is suggested for primary and secondary frequency control simulations, as well. The purpose is to investigate the influence of power generation structure on power system frequency control.

PL

Podstawowym celem pakietu „3x20" Unii Europejskiej jest zmniejszenie o 20% emisji dwutlenku węgla. Z tego powodu oczekuje się w Polsce rozwoju energetyki wiatrowej, podobnie jak energetyki jądrowej, a także mini elektrociepłowni. Elektrownie wiatrowe i jądrowe wnoszą specyficzne problemy w regulacji automatycznej częstotliwości systemu elektroenergetycznego. Farmy wiatrowe wymagają pod tym względem wspomagania przez elektrownie konwencjonalne; bloki jądrowe wymagają odpowiedniego dostosowania struktury i nastawień ich układów regulacji automatycznej. Przedstawiono koncepcję wielomaszynowego modelu matematycznego systemu elektroenergetycznego, opartą na modelach matematycznych tzw. reprezentatywnych turbozespołów i bloków. Taki uproszczony model matematyczny jest proponowany do symulacyjnych badań porównawczych regulacji automatycznej częstotliwości systemu elektroenergetycznego. Ich celem jest analiza wpływu struktury wytwarzania energii elektrycznej na regulację automatyczną częstotliwości systemu elektroenergetycznego.

3

Sterowanie automatyczne częstotliwości systemu elektroenergetycznego zasilanego elektrownią wiatrową wspomaganą elektrownią konwencjonalną

Domachowski Z., Ghaemi M.

Systems : journal of transdisciplinary systems science

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2008

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Vol. 13, spec. iss. 1/2

158--164

EN

Windpower is considerably increasing in many countries worldwide. Unfortunately, windfarm produces unreliable output due to the vagaries of the wind profile and so can not meet demand. Without action these would be major problems with fluctuating power quality. Wind energy source needs local support from conventional sources. The requirements concerning the reliability and quality of electric energy supply can be most satisfactory fulfilled when a windfarm is connected to a large electric power system. A strict cooperation is required between the large power system control and the windfarm control system to provide among others that any fluctuations of windpower supply should be damped as near to the windfarm as possible to avoid considerable disturbances of frequency and voltage in the electric power system. The distance between a windfarm and a large electric power system is very often too long to build a transmission line on an economically sound basis. It becomes unavoidable to produce windpower in a separate electric power system. Any fluctuations of windpower have to be damped due to an appropriate action of a conventional power plant support. To provide such a support the following aid concepts are possible: gas turbine power plant, diesel engine power plant, pumped storage power station. Investigation on the control of a separate electric power system composed of windpower farm and gas turbine power plant have been carried out. Effects of turbulence in the wind different amplitude and frequency of wind speed variations on gas turbine power plant control system have been simulated. The gas turbine power plant control system structure and parameters have been adopted to provide limiting the power and frequency fluctuations resulting from wind turbulence.