undergraduate thesis
Electromotive plants on board

Luka Marđetko (2016)
University of Zadar
Maritime Department
Division of Maritime Engineering
Metadata
TitleElektromotorna postrojenja na brodu
AuthorLuka Marđetko
Mentor(s)Marijan Gržan (thesis advisor)
Abstract
Brodski elektromotorni pogon je sastavljen od električnih strojeva i uređaja koji koristeći i trošeći električnu energiju proizvode mehaničku energiju. Elektromotorni pogon se sastoji od elektromotora, sustava za napajanje i sustava za upravljanje i regulaciju. Prema vrsti struje koja se koristi za njihovo pokretanje dijele se na istosmjerne i izmjenične elektromotore.Od ukupne potrošnje električne energije na brodu na elektromotorne pogone otpada između 75 i 95 % (ovisno o vrsti broda). U tu skupinu trošila ubrajaju se električni pogoni vitala, pumpa, kompresora, ventilatora i raznih pomoćnih strojeva nužnih za rad glavnih strojeva. Među najznačajnijim čimbenicima pri vrednovanju elektromotora, kao uostalom i većine brodske opreme, s obzirom da direktno smanjuju kapacitet broda, njihovi su masa i dimenzije.Kod ugrađenih velikih motora jako je važna i mogućnost popravka na licu mjesta. Preventivno održavanje mora biti što jednostavnije, primjereno stručnosti posade, i ni u kom slučaju ne smije remetiti tehnološki proces, što znači da je po obimu provedivo tijekom boravka u luci, ili da ne zahtijeva zaustavljanje pogona. Istosmjerni elektromotori imaju gotovo idealne vanjske karakteristike motora koji povezuje brzinu vrtnje i razvijeni moment, mogućnost jednostavnog dobivanja promjenljivog istosmjernog napona napajanja, jednostavni su u upravljačko-regulacijskom smislu te imaju široki opseg upravljivosti brzinom vrtnje. Rad istosmjernog elektromotora zasniva se na stvaranju elektromagnetske sile na vodi koji se nalazi u magnetskom polju. Elektromotor izmjenične struje (tzv. izmjenični motor) može biti asinkron i sinkron. Da li će motor raditi kao sinkroni ili asinkroni zavisi o tome kako mu je izveden rotor. Statori sinkronog i asinkronog motora se ne razlikuje. U njemu struje trebaju stvoriti okretno magnetsko polje. Kao i transformatori asinkroni motori mogu imati tri vrste električkih kvarova: spoj s masom, kratki spoj i prekid strujnog kruga. Danas se sinkroni motori uglavnom koriste u sklopu reguliranih elektromotornih pogona što znači da su napajani izpretvarača frekvencije koji ih ujedno na najbolji mogući način i upućuju polako podižući frekvenciju i napon uz kontrolu položaja rotora. Elektromotori obavezno imaju podnaponsku zaštitu, zaštitu od kratkog spoja i zaštitu od preopterećenja. Do strujnog udara dolazi kada se električni krug zatvori kroz čovjeka i pri tome poteče struja koja prelazi njegov prag osjeta (0,6-3mA). Najopasniji su međutim strujni udari kada se strujni krug zatvori kroz srce (ruka-ruka i ruka-noga) kad i bez vidljivih ozljeda može zbog zatajenja rada srca nastupiti smrt. Najznačajnija i najviše korištena tehnička mjera za zaštitu od strujnog udara je zaštitno uzemljenje koje je u slučaju broda ispravnije zvati izjednačenjem potencijala.
KeywordsElectromotive plants electrical energy mechanical energy electric motor ship DC electric motor AC electric motor asynchronous motor synchronous motor current.
Parallel title (English)Electromotive plants on board
GranterUniversity of Zadar
Lower level organizational unitsMaritime Department
Division of Maritime Engineering
PlaceZadar
StateCroatia
Scientific field, discipline, subdisciplineTECHNICAL SCIENCES
Traffic and Transport Technology
Maritime and River Traffic
Study programme typeuniversity
Study levelundergraduate
Study programmeNaval Mechanical Engineering and Maritime Industry Technology
Academic title abbreviationuniv. bacc. ing. nav. mech.
Genreundergraduate thesis
Language Croatian
Defense date2016-03-15
Parallel abstract (English)
The marine electric motor is made up of electrical machinery and devices which by using and consuming electricity produce mechanical energy. The electromotive plant consists of an electric motor, power and management systems and control system. According to the type of electricity used to run them they are divided into DC and AC electric motors. Of the total electricity consumption on board the electromotive plants consume between 75 and 95% (depending on the type of ship). This group of consumers includes the electric winch drives, pump, compressor, fan and various auxiliary equipment necessary for the operation of the main engines. Among the most important factors in the evaluation of electric motors, like the majority of marine equipment, as it directly reduces the capacity of the ship, are their weight and dimensions. With large built-in engines, the possibility of on the spot repairs is very important. Preventive maintenance should be as simple as possible, including appropriate expertise of the crew, and in no case should interfere with the technological process, which means that it must be executed during the stay in the port, or that it does not require stopping the system. DC motors have almost ideal external engine characteristics which connect the rotation speed and developed torque, they have the ability to easily obtain a variable DC voltage power supply, they are easy to control and regulate and have a wide range of handling the speed of rotation. The work of the DC electric motor is based on the creation of the electromagnetic force in a guide which is located in the magnetic field. Electric motor AC (ie, AC motor) can be asynchronous and synchronous. Will the engine operate as synchronous or asynchronous depends on how the rotor is implemented. Stators of a synchronous and asynchronous motor are no different. Currents need to be created by a rotating magnetic field. Like transformers, asynchronous motors can have three types of electrical faults: ground connection, short circuits and interruption of circuit currents. Today, the synchronous motor is mainly used as part of regulated electromotive plants which means that they are powered from inverters, which are in the best possible way guided by slowly raising the frequency and voltage by controlling the position of the rotor. Electric motors must have overvoltage protection, short circuit protection and overload protection. A power surge occurs when the electrical circuit is closed through a man and at the same time expires current that exceeds his threshold of sensation (0,6-3mA). However the most dangerous electric shock is when the circuit is closed through the heart (hand-arm and hand-foot) and when there is no visible injuries death by heart failure can occur. The most important and most used technical measures to protect against electric shock is grounding of the ship, which in the case of ships, is more correctly called equalization potential.
Parallel keywords (Croatian)Elektromotorni pogon električna energija mehanička energija elektromotor brod istosmjerni elektromotor izmjenični elektromotor asinkroni motor sinkroni motor struja.
Resource typetext
Access conditionOpen access
Terms of usehttp://rightsstatements.org/vocab/InC/1.0/
URN:NBNhttps://urn.nsk.hr/urn:nbn:hr:162:204012
CommitterMarta Unković