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U ovom magistarskom radu analizira se rad elektromehaničkih pretvarača energije (aktuatora). Pritom se razmatraju tri pristupa. Prvi pristup koristi elektromehanički model pretvorbe energije s koncentriranim parametrima. U tom modelu aktuator je prikazan crnom kutijom unutar koje se bez gubitaka pohranjuje magnetska energija te obavlja pretvorba energije iz električke u mehaničku. Za definiranje svojstava crne kutije koristi se model linearnog magnetskog kruga. Dobivaju se analitičke funkcije stanja crne kutije. Drugi pristup također koristi elektromehanički model pretvorbe energije, a za definiranje funkcija stanja crne kutije koristi magnetostatički model konačnih elemenata koji se analizira u nizu diskretnih statičkih stanja. Rezultati tih analiza interpoliraju se bikubičnom spline-interpolacijom da bi se dobile glatke funkcije stanja crne kutije. Treći pristup koristi dinamički elektromagnetsko-strukturni model konačnih elemenata s malim pomakom strukture. Analiza ovog modela izravno daje dinamičko ponašanje aktuatora, no on je ograničen malim iznosom pomaka strukture i korištenjem strujne umjesto naponske pobude. Najpotpuniju informaciju i najbolje slaganje s mjerenjima dala je analiza prema drugom pristupu. Analiza prema trećem pristupu bitna je jer jedina daje uvid u dinamičke učinke kao što su vrtložne struje. In this thesis, the dynamic behavior of electromechanical actuators is studied. Three approaches are proposed. The first approach utilizes a lumped-parameter electromechanical energy conversion model. The actuator is presented as a black box containing a lossless system which performs the conversion between electrical and mechanical energy. The properties of the black box are derived from a linear magnetic circuit model. The properties are expressed as analytical functions of the state of the black box. The second approach also utilizes the lumped-parameter model, but it derives the properties of the black box from a magnetostatic finite element model which is analyzed in a series of static states. The results of these analyses are interpolated using a bicubic spline interpolation to acquire smooth functions of the black box state. The third approach utilizes a dynamic electromagnetic-structural finite element model with small structural motion. The dynamic behavior is obtained directly by analyzing the model, but the model is limited by small maximum displacement of the moving part and by the application of a current source instead of a voltage source. The most complete information about the dynamic behavior of the actuator is obtained from the second approach. The unique value of the third approach is that it gives information about the dynamic effects such as eddy currents.

The paper presents the results of the simulation of a linear solenoid actuator. The simulation involves combining of a magnetostatic finite-element field calculation with a lumped-parameter electromechanical device simulation. The finite-element calculation is used to create a bicubic-spline interpolated function Ř = Ř(i, x), where Ř represents magnetic flux linkage, i represents coil current, and x represents armature position. This function is used in a lumped-parameter time-domain simulation of the response of the actuator to a voltage pulse. The results are compared with measurements.