Supervision and optimization of electricity consumption in robotic welding cell

Izdelovalci strojne opreme želijo svojim kupcem ponuditi tehnološko dovršeno robotsko celico, pri čemer je za kupca lahko pomemben vidik tudi pregled nad porabo in njeno optimizacijo za prihranek stroškov električne energije. Diplomska naloga obravnava nadzor in optimizacijo porabe električne energije varilne naprave, robota in mize – treh največjih porabnikov robotske varilne celice. V prvem delu so predstavljeni njeni porabniki: glavna stikalna omara, robotski krmilnik, robotski manipulator, miza ali pozicioner, vpenjalno-pozicionirno orodje, varilni sistem, čistilnik, dvoročni samostoječi pult in komandna plošča. Robotski krmilnik vodi mnogokratne naloge z možnostjo vodenja do osem robotov. V glavni stikalni omari se nahajajo vsi napajalni gradniki celice. Gibljivi strojni del celice sta robotski manipulator in miza z vpenjalno-pozicionirnim orodjem. Varilni sistem sestavljajo varilni izvor, povezni paket in varilna pištola. Čistilnik skrbi za čiščenje šobe varilne pištole. Dvoročni samostoječi pult in komandna plošča, na kateri so vsa glavna stikala, se uporabljata za upravljanje celice. Z meritvami parametrov robota, mize in varilne naprave smo izdelali dve preglednici nadzora porabe električne energije in dve predlogi HMI (human-machine interface). V njih se podatki sami preračunajo do porabe električne energije v kilovatnih urah in stroškov porabe v evrih za en, sto tisoč ter tri milijone zvarjenih kosov. V primerjavi varilna naprava porabi med tri do štirikrat več električne energije kot robot in miza skupaj, razmerje je odvisno predvsem od izbranega varilnega postopka. Porabo električne energije je možno najbolj optimizirati pri varilni napravi z dobro izbiro in nastavitvijo varilnega postopka z nanašanjem varilnega materiala s pulziranjem toka. Pri robotu in mizi je največji prihranek energije možen z izklopom servo regulacije motorjev robota, medtem ko robotska varilna celica v času odmorov za malico ne obratuje.Hardware producers strive to offer their customers a technologically perfected robotic cell. Two important factors that customers take into consideration are the overview of energy consumption and a possibility for optimization with regard to the energy cost savings. This thesis deals with the electricity consumption of a welding machine, robot and positioner, three main energy consumers of a robotic welding cell.The first part of the thesis describes the consumers of a robotic welding cell: robot controller, main switch cabinet, robot manipulator, positioner, clamping-positioning tool, welding system, cleaner, two-handed stand-alone counter and command panel. The robot controller performs multiple tasks and has the possibility to supervise up to eight robots. The power components are located in the main switching cabinet. The moving parts of the robotic welding cell are the robot manipulator and the positioner with the clamping-positioning tool. The welding system is composed of a welding source, a connecting package and a welding pistol. The cleaner carries out cleaning of the welding pistol\u27s nozzle. The two-handed stand-alone counter and the command panel with all the main switches are used to operate the robotic welding cell. By measuring the parameters of the robot, the positioner and the welding source we compiled two tables showing electricity consumption and designed two HMI (human-machine interface). The tables automatically calculate the electricity consumption for one, 100,000 and 3 million welded products in kilowatt hours and the costs in EUR. In comparison to the robot with the positioner, the welding source consumes three to four times more power, whereby the ratio mainly depends on the selected welding process. The electricity consumption of the welding tool can be best optimized by good setting and choosing the right welding process. With regard to the robot and the positioner, the most electricity can be saved by deactivating the servo regulation of the robot motors during the lunch time, when the robotic welding cell is not in operation