Model motora s unutarnjim izgaranjem za ispitnu stanicu

master's thesis

• Title (english): Testbed internal combustion engine simulator
• Author: Jurica Mustać
• Mentor: Darko Kozarac (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2018-12-06, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering

Abstract

Da bi se smanjili troškovi razvoja automobilskih motora s unutarnjim izgaranjem, njihovo početno testiranje i nadzor performansi se odvija na testnim stanicama. Pomoću električne kočnice motora i upravljačke jedinice, motor s unutarnjim izgaranjem se može dovesti u bilo koju željenu radnu točku ili priključiti na postojeći matematički model vozila i okoline. Da bi se motor lakše i u kraćem vremenu podesio za testnu stanicu, potrebno je izraditi pouzdani matematički model motora pomoću kojeg će se moći procijeniti karakteristike stvarnog motora. U prvom dijelu izrade modela motora, definirana je točnost i kompleksnost samog modela. S tim pretpostavkama se odabiru dijelovi dinamike motora koji će se opisati teorijski ili empirijski, a sve sa svrhom provođenja proračuna u realnom vremenu ili čak brže od toga. Opisan je model u domeni kuta zakreta koljenastog vratila te su verificirani rezultati s relevantnim software-om. Nadalje je opisan model u vremenskoj domeni s kojim je moguće pokretati simulaciju kroz neko vremensko razdoblje i povezati s modelima ostatka vozila. U drugom dijelu rada, izrađeni su relevantni regulacijski sustavi za upravljanje značajkama rada motora, od regulatora brzine vrtnje u praznom hodu do tempomata. Ovi regulacijski sustavi su ključni za završne performanse motora i njegovu stabilnost u željenim radnim točkama. Sliding mode regulator je izabran kao nazivni regulator zbog svojih robusnih svojstava i dobrih performansi u raznim radnim točkama. Na kraju rada, model je preveden u globalno priznati standard za razmjenu matematičkih modela (FMU) koji se izvodi brže od opisanog modela u Simulink-u i ponaša se kao svojevrsna crna kutija. Vidljivi su samo ulazi i izlazi iz modela, dok se sastavu modela ne može pristupiti niti ga izmijeniti.

Abstract (english)

To reduce the research and development costs of the internal combustion engines (ICE), their initial testing and performance control is conducted on the testbeds. By using eletrical brake with control unit, the ICE can be run at any desired operating point or can even be connected to an existing mathematical model that simulates the rest of the vehicle and the environment. To shorten the time it takes to set up the ICE to the testbed, a reliable ICE model has to be designed in order to accurately calculate characteristics of a real engine. In the first part of the thesis, the desired accuracy and complexity of the model are defined. With these assumptions, parts of the model that will be described theoretically or empirically are selected in order to enable the model to in real time, or even faster. A crank-angle dependent model is described and the results are verified with the relevant software. Afterwards, the time-dependent model is described, with whom it is possible to run the simulation in the desired time frame and to connect it with the models of the rest of the vehicle.In the second part of the thesis, the relevant control systems for engine performance are designed, from the idle speed controller to the cruise control system. These control systems are crucial for the final engine performance and its stability in the desired operating points. Sliding mode control was selected as the default controller due to its robust properties and good performance in various engine states. Finally, the model is compiled to a globally recognized standard for mathematical model sharing (FMU) which runs faster than the model designed in Simulink and acts as a sort of a black box. Only the inputs and the outputs of the model are visible, while the content of the model is inaccessible and unchangeable.

• Keywords: testna stanica; motor s unutarnjim izgaranjem; model u stvarnom vremenu; upravljački sustav; FMU
• Keywords (english): testbed; internal combustion engine; real-time model; engine control unit; FMU
• Language: english
• URN:NBN: urn:nbn:hr:235:531126
• Study programme: Title: Mechanical Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka strojarstva (magistar/magistra inženjer/inženjerka strojarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2019-05-24 12:56:58