This work evaluates new experimental methods for determining the magnetically nonlinear characteristics for different electromagnetic devices. Procedures for determining iron core models are based on electrical variables, which are measured on the terminals of an individual device. Six different methods are compared in this work. From the obtained results it is evident, which method gives the best result for a particular case. The best results were obtained with the methods, where the tested device is excited by a sequence of stepwise changing voltage.
COBISS.SI-ID: 9925654
The authors are first one which applied differential evolution for solving the global optimization problems. Two members of the research program were invited to prepare a chapter with optimization of radial active magnetic bearings for spindle drive. The optimization aim is to achieve a radial maximum force at a minimum mass of the entire construction. Predefined design parameters are the bearing outer diameter, the shaft diameter, the air gap and the maximal generated force. The results have been already used in several industrial projects, which is very important.
COBISS.SI-ID: 10107926
The behavior of a power transformer depends considerably on the properties of the magnetically nonlinear iron core. This paper deals with the modeling of a three-phase, three-limb power transformer laminated iron core. The proposed iron core model is given by the corresponding partial derivatives of measured flux linkage characteristics. The numerical results obtained by the proposed iron core model agree with the measured results much better than those obtained by the existing nonlinear iron core model known from literature. The results have been already used in several industrial projects.
COBISS.SI-ID: 5504340
This contribution is a result of planned research work within the program group. The main result of this work is a development of universal optimization algorithm based on differential evolution strategy, which can be used for the design of different kind of insulation elements. A medium-voltage switchgear insulation element was optimized by this program. The goal for optimization was to achieve adequate capacitance of the voltage divider, which is a component of the device, and the optimal distribution of electric field strength inside the insulation element.
COBISS.SI-ID: 10266390
This paper deals with a resistance spot welding system. The unequal resistances of the two transformer's secondary circuits and the different characteristics of the diodes of output rectifier certainly lead to the magnetic saturation which, causes the unwanted spikes in the transformer's primary current and over--current protection switch--off. This disadvantage of classical spot welding systems is completely eliminated by the proposed advanced hysteresis controller, which keeps transformer iron core saturation within prescribed bounds regardless of how unequal the ohmic resistances are.
COBISS.SI-ID: 11993110