In the master's thesis, the dynamic model of electric drive was developed. Specific focus was given to the physical representation of electric motor, inverter and the implementation of the control algorithm.
Firstly, we investigated the mathematical models of a permanent magnet synchronous motor in the rotor reference frame. We outlined four possible representations of flux-current relationship with different degree of complexity and determined for which applications each of them is the most suitable. Then, we focused on the inverter model, where special consideration was given to the proper description of the voltage drop on the power switches.
Secondly, the losses in the SMTM were considered in detail. In order to determine losses in permanent magnets, we developed a hybrid model based on combination of 2-D finite-element method and an analytical calculation in three dimensions. The model was subsequently verified with results from a 3-D finite element method model.
Thirdly, the above theoretical considerations were implemented in dynamic simulation using Matlab Simulink environment. It was demonstrated, that the resulting model of the electrical drive allows for rapid simulations of the various operational conditions. At the end, the simulations were compared with measurements on the actual drive. The agreement between simulations and measurements was good, in some cases even excellent.
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