Modernisation of electric drive in gantry crane

Diplomsko delo obravnava zamenjavo krmilnega sistema vožnje mostnega dvigala in mačka. Dvigalo je trenutno krmiljeno s kontaktorsko tehniko, sedaj pa bo vožnja dvigala in mačka krmiljena s frekvenčnima pretvornikoma. Za pravilno zamenjavo električnih komponent moramo poznati vse lastnosti dvigala. Tako je na začetku dela opisano obstoječe stanje mostnega dvigala z vsemi lastnostmi električnih strojev in razlago trenutnega delovanja sistema. Za potrebe pravilnega izbora komponent so izračunane dinamične obremenitve zaviranja obeh sklopov, ki bosta sedaj krmiljena s frekvenčnim pretvornikom. Poznavanje teh obremenitev je ključno za izbiro pravilnega zavornega upora, kar tekom naloge tudi pokažem. Problem lahko nastane predvsem pri zelo zahtevnih sistemih, kjer so cikli voženj zelo pogosti in kratki. Takrat je ključno, da je upor pravilno dimenzioniran, da ne pride do okvare na frekvenčnem pretvorniku. Prikazan je tudi postopek nastavitve frekvenčnih pretvornikov proizvajalca Vacon serije NX_.Thesis deals with the replacement of the drive control system of gantry crane and a trolley. The lift is currently controlled by contactor technique which will now be replaced with the frequency converter in bridge and trolley application. To do a proparly replaicement of electrical components we should be familiar with the status of the crane. Thus, at the beginning of the thesis is description of the existing situation of gantry crane with all the properties of electrical machinery and interpretation of the current operation of the system. For the purposes of proper selection of components are calculated dynamic load inhibition of both sets, which will now be controlled by frequency converters. Knowledge of these datas is the key to select the correct braking resistor what I show during thesis. The problem may occur especially in very complex systems, where drive cycles are very common and short. The key is that the brake resistor is correctly dimensioned, to avoid damage to the frequency converter. In thesis is also shown the process of setting the frequency converters of Vacon manufacturer