52 research outputs found
Energy management system of the hybrid ultracapacitor-battery electric drive vehicles
The search for new, alternative propulsion and energy sources in transport is one of the economic and technological priorities of the current decade. The modern development of hybrid drives and electric means of transport makes it possible to at least partially diversify conventional drive systems. The study discusses the use of a battery and ultraca-pacitor in electric vehicles. Simulation analyzes of energy flow were performed using the solutions of electric drive systems and various energy storage control algorithms. The research was carried out in relation to the use of braking energy, its conversion into electricity and its storage in a battery or ultracapacitor. The operating conditions of the battery and the ultracapacitor were assessed in terms of specific energy consumption while driving. The article pro-posed the use of a drive system connected in series, the last link of which was an ultracapacitor. Such a solution signif-icantly reduced the use of the battery as well as its regular charging-discharging. At the same time, it required the use of a high-capacity ultracapacitor, which contributed to increasing its charging time. The analyzes were carried out using standardized research tests as well as tests in real traffic conditions. The research was carried out with the use of the AVL Cruise software for the analysis of energy flow in vehicles; a middle class passenger vehicle was selected for the tests, equipped with an electrochemical battery and – in the next stage of the research – an ultracapacitor. Three research models were used: I) typical electric drive system; II) a system with the use of ultracapacitors ran by a simple control algorithm; III) a system with the use of ultracapacitors with an advanced control algorithm (the algorithm took into account the change of driving conditions to the ultracapacitor charging conditions). The advantages of using ultracapacitors in the electric drive of a vehicle were demonstrated, especially for results obtained in real traffic condi-tions. Analyzing the simulation tests results allowed to determine the most advantageous options of utilizing these systems, in particular in the aspect of increased possibilities of algorithms controlling the flow of electricity in the drive system
Thermodynamical evaluation of usefulness of future hydrocarbon fuels for use in compression ignition engines
The tendencies in the regulations concerning the emission of toxic compounds by the diesel engines of the rail vehicles
Z uwagi na rosnące skażenie środowiska producenci silników spalinowych do pojazdów trakcyjnych poszukują możliwości zmniejszenia emisji substancji toksycznych, będących wynikiem spalania paliwa. Wprowadza się coraz większe ograniczenia prawne, dotyczące emisji CO, HC, NOx i PM. Kierunki tych zmian są coraz bardziej zbieżne w przepisach europejskich i amerykańskich zarówno w odniesieniu do testów badawczych jak i dopuszczalnych limitów emisji.Considering the increasing environmental contamination the producers of the diesel engines for the traction vehicles search for the possibilities of the reduction of emission of the toxic substances being the results of fuel combustion. The heavier and heavier legal limitations concerning the emission of CO, HC, NOX and PM are introduced. The directions of these changes are the more and more convergent in the European and American regulations both with reference to the research tests and the permissible limits of emission
Symulacyjna analiza energochłonności pojazdów elektrycznych w testach badawczych
The assessment of energy flow through electric vehicle systems makes estimating their energy consumption possible. The article presents analyzes of the energy consumption of electric vehicles in selected driving tests (NEDC, WLTC and in real traffic conditions – RDC test) in relation to the vehicles different curb weight. The use of electric motors was also analyzed, providing their operating ranges, data of the energy flow in batteries and the change in their charge level. Simulation tests and analyzes were carried out using the AVL Cruise software. It was found that despite similar vehicle energy consumption values in NEDC and RDC testing, there are significant differences in energy flow in vehicle subsystems. The changes in the battery charge level per 100 km of test drive are similar in both the WLTC and RDC tests (6% difference); for the NEDC test, this difference is the greatest at 25% (compared to the previous tests). The energy consumption of electric vehicles depends significantly on the test itself; the values obtained in the tests are in the ranges of 10.1–13.5 kWh/100 km (NEDC test); 13–15 kWh/100 km (WLTC test) and 12.5–16.2 kWh/100 km in the RDC test. The energy consumption values in the NEDC and WLTC tests, compared to the RDC test, are approximately 20% and 10% lower, respectively. Increasing the vehicle mass increases the energy consumption (increasing the vehicle mass by 100 kg was found to increase the energy consumption by 0.34 kWh/100 km).Ocena przepływu energii przez układy pojazdów elektrycznych umożliwia oszacowanie ich energochłonności. W artykule przedstawiono analizy dotyczące zużycia energii pojazdów elektrycznych w wybranych testach jezdnych (NEDC, WLTC oraz w rzeczywistych warunkach ruchu – test RDC) w odniesieniu do zróżnicowanej masy pojazdów. Analizie poddano również wykorzystanie silników elektrycznych, przedstawiając mapy ich pracy, wielkości przepływu energii w akumulatorach oraz stopień zmiany ich naładowania. Badania i analizy symulacyjne wykonano z wykorzystaniem oprogramowania AVL Cruise. Stwierdzono, że mimo podobnych wartości energochłonności pojazdów w testach badawczych NEDC oraz RDC, to występują znaczące różnice przepływu energii w układach akumulacji pojazdów. Zmiany stopnia naładowania akumulatora odniesione do 100 km testu są zbliżone w testach WLTC oraz RDC (różnica 6%); dla testu NEDC różnica ta wynosi maksymalnie 25% (w odniesieniu do poprzednich testów). Energochłonność pojazdów elektrycznych jest silnie zależne od testu badawczego; wartości uzyskane w testach kształtują się na poziomie 10,1–13,5 kWh/100 km (test NEDC); 13–15 kWh/100 km (test WLTC) oraz 12,5–16,2 kWh/100 km w teście RDC. Wartości energochłonności w testach NEDC oraz WLTC są odpowiednio mniejsze o około 20% i 10% w odniesieniu do testu RDC. Zwiększenie masy pojazdu zwiększa zużycie energii (zwiększenie o 100 kg masy pojazdu zwiększa zużycie energii o 0,34 kWh/100 km)
Numerical investigation of lambda-value prechamber ignition in heavy duty natural gas engine
Turbulent Jet Ignition systems are mainly dedicated to the combustion of lean mixtures of natural gas in heavy duty engines. The use of such a system in combination with lean mixtures leads to an increase in its overall efficiency. The article presents simulation analyzes of the impact of the air excess coefficient occurring in prechamber on the combustion process: combustion indicators and emission indicators. Tests on a single-cylinder engine with a displacement of about 4 dm3 at medium mixture (IMEP = 1.0 MPa) were carried out using the AVL Fire software. It was found that the incineration of global lean mixtures (λ = 2) is effective when initiating this process (in the prechamber) with a charge of a stoichiometric composition. A strong relationship was found between the thermodynamic indicators in both prechamber and main chamber and the air excess coefficient initiating combustion
Modeling of Fuel Cells Characteristics in Relation to Real Driving Conditions of FCHEV Vehicles
Fuel cells are one of the zero-emission elements of modern automotive drive systems. This article presents theoretical identification of the component parameters of indicators for the fuel cell operating conditions. Activation, ohmic, and mass transport losses were identified. Current–voltage characteristics were provided along with an analysis of typical cell losses. The actual performance characteristics of fuel cells were analyzed for Toyota Mirai I and II generation vehicles. The fuel cells operating conditions were derived and analyzed in the context of real driving conditions. Therefore, urban, rural, and motorway conditions were used. The vehicles were equipped with PEM fuel cells supplying power equal to 114 kW (1st gen.) or 128 kW (2nd gen.). The average fuel cell stack power values depend on the driving conditions: urban (about 10 kW), rural (20 kW) and motorway (about 30–40 kW) driving modes. The different power ratings of fuel cells combined with different battery generations resulted in a variation in the cells operating conditions. Analyses conducted in various traffic conditions indicated the possibility of determining losses related to the fuel cells. The analysis of fuel cell losses shows the greatest values for activation losses when the cells are under high load (for both generations)—i.e., in motorway driving conditions. The voltage of resistive losses reached its maximum in urban driving conditions when the load on the fuel cells was small
Analysis of mass transfer in marine engine with prechamber combustion spark ignition system
The development of combustion systems construction is associated with the possibility of increasing the thermal or overall efficiency of an internal combustion engine. The combustion systems currently in use (mainly related to direct fuel injection) are increasingly being replaced by hybrid systems, including direct and indirect injection. Another alternative is the use of prechambers in new combustion systems. This article concerns the thermodynamic aspect of this issue – namely, the assessment of the inter-chamber f low of a marine engine equipped with a prechamber combustion spark ignition system. The research was carried out using mainly one-dimensional simulation apparatus, and detailed analyses were presented using three-dimensional modeling. The tests included the engine model at medium load. Differences in mass f lows were shown at different diameters and different numbers of holes from the preliminary chamber (while maintaining the same cross-sectional area). Similar values of excess air coefficient during ignition of the fuel dose in the prechamber were observed, which resulted in changes in the f low between the prechamber and the main chamber. The differences in mass f low affected the temperatures achieved in the individual combustion chambers. Based on three-dimensional analyses, the mass transfer rate between the chambers and the temperature distribution were assessed during fuel ignition initiated in the prechamber
Control algorithms for a Range Extender vehicle with an combustion engine
The combination of two drive sources: the internal combustion engine and the electric motor in the hybrid drive system requires an appropriate control system to manage their operation. It relies on many variables, and the greater the degree of drive hybridization the greater is the degree of interdependence of the parameters involved. The article presents solutions of electric drive control algorithms with an additional power source in the form of an internal combustion engine (Range Extender). The results of simulation analyzes in the AVL Cruise program are presented, taking into account three control algorithms and two driving cycles. The obtained results indicate the necessity to take various input quantities into account in order to optimize the use of the combustion engine
Requirements and guidelines for light constructional materials with minimal impact on natural environment
W artykule zaprezentowano przegląd lekkich materiałów konstrukcyjnych ze stopów metali lekkich (zwłaszcza stopów aluminium) oraz kompozytów (wysokowytrzymałych tworzyw sztucznych) mających zastosowanie w lekkich konstrukcjach pojazdów drogowych i szynowych. Zaprezentowano tendencje w produkcji materiałów lekkich ze szczególnym uwzględnieniem ograniczenia kosztów w ich wytwarzaniu oraz ograniczeniu ich oddziaływania na środowisko naturalne. Wskazano ponadto na ekonomiczne aspekty w procesie recyklingu i utylizacji tych materiałów jako szansa w ograniczeniu szkodliwego oddziaływania zastosowanych lekkich materiałów na środowisko naturalne w tym ograniczenie emisji substancji szkodliwych do atmosfery oraz zmniejszenie tzw. efektu cieplarnianego. Artykuł powstał w ramach projektu rozwojowego nr 100047/06/2009 pt.: "Konstrukcja pojazdu szynowego z zastosowaniem najnowszych lekkich materiałów o wysokich parametrach wytrzymałościowych i o minimalnym oddziaływaniu na środowisko naturalne ".In this paper it is presented the review of light constructional materials madę of alloys of light metals (especially the aluminium alloys) and composites (high-strength artificial materials) that are applicable in the light construction of road and rail vehicles. It is also presented the tendency in production of light materials with special consideration of the cost reduction of its manufacturing and limiting their impact on natural environment. Besides this paper gives attention to economic aspects of recycling and utilization process of these materials, as a chance in limiting of emission of harmful substances to the atmosphere and reducing the greenhouse effect. This paper is prepared within a framework of developing projects No: 100047/06/2009: "Construction of rail vehicle with application of the newest light materials with high strength parameters and minimal impact on natural environment
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