Analyza necharakteristickych harmonickych proudu polovodicovych menicu.

This thesis deals with low-frequency analysis of phase currents taken by semiconductor converters from a power distribution network which is unbalanced especially in amplitude. This effect leads to higher distortion of phase currents. There are additional frequency components presented in the frequency spectrum of these currents. The main attention is paid to the converters designed as a power source for voltage inverters. The next analysed type of converter is a three-phase fully controlled bridge rectifier working to an inductive load. In this case there is considered, in addition to the unbalanced power course, non-symmetrical firing pulses. The result of this work is the explanation of the physical patterns arising from non-characteristic harmonics, including their dependence on the value of effect noticed above. The next contribution of this thesis consists in providing background for the CENELEC Commission in order to familiarise contemporary standards focusing on emission of harmonic currents in low-voltage power supply systems.Available from STL, Prague, CZ / NTK - National Technical LibrarySIGLECZCzech Republi