National Repository of Grey Literature 3 records found  Search took 0.00 seconds. 
The Eddy Current Losses of High-Speed Solid Rotor Induction Machine as Function of the Radial Air-Gap Lenght
Bárta, Jan
This paper introduces that the appropriately selected air-gap width have major impact in terms of efficiency for high-speed induction machines. Machine of interest is high-speed solid rotor cage induction machine intended for helium turbo-circulator. Proposed study is done from electromagnetic and thermal point of view. Presented results can be used as a guideline for air-gap length selection for others high-speed solid rotor induction machines.
Design of Electrical Machine 6 kW, 120 000 rpm for Helium Turbo-Circulator
Bárta, Jan ; Rafajdus,, Pavol (referee) ; Dušek,, Jiří (referee) ; Ondrůšek, Čestmír (advisor)
The induction machine with a squirrel cage is a workhorse of the industry. The main advantage of an induction machine is the low manufacturing price, simple and robust construction, low maintenance requirements. However, for high-speed applications, induction machine with a squirrel cage requires design modification due to the mechanical restrictions. The objective of this thesis is to show design process, methodology and assembly of the induction machine for high-speed applications. In this thesis, the rotor dimensioning data are presented. The results are demonstrated on the design of the 6 kW, 120 000 rpm solid rotor squirrel cage induction machine. This thesis also contains calculation and design of three different electrical machine topologies for a turbo circulator application. The electrical machines are designed with 6 kW output power at 120 000 rpm. The machines are estimated by using electromagnetic, thermal, and mechanical calculations. The drawbacks and advantages of each topology under study are described. For other high-speed applications, a comparative method helps in choosing the suitable electrical machine topology by examinations of discussed criteria. Rotor design effect on the electromagnetic performance of the induction machine is shown. Mechanical stresses are calculated with Finite Element Method analysis. Various assembly technologies to produce solid rotor with squirrel cage are discuss and compare. Describe approach enables high electromagnetic performance and durable construction of the high-speed induction machine. Work is confirmed by measurement on the manufactured prototype.
Simulation of Electromechanical System Control Structures
Petruška, Ľubomír ; Blaha, Petr (referee) ; Václavek, Pavel (advisor)
Construction of motor models is the main topic of this project. Mathematical characterization of AC machine, permanent magnet synchronous motor, separately-excited DC motor, series-wound DC motor, permanent magnet DC motor, switched reluctance motor is also described. Design of models is based on mathematical description of particular motors. Models are created in Matlab Simulink. Each model is implemented in continuous and also in discrete time variant. Selected models are implemented also on processor from Freescale 56F800E Hybrid Controller family. Each model has individual graphic user interface. Besides motor models, there is description and easy algorithm of Space Vector Modulation. Model of this method is also created. Models are build-up into a library, which can be used for simulations and tests of control structures. Results of models simulations are presented at the end of this project. Simulation of models that are implemented on processor is also made in Matlab Simulink environment and is compared to simulation of models that are implemented directly in Matlab Simulink.