Mikhalsky V. Matrix Converters for Electrical Drives (Control, Current Commutation).

Object - process of frequency and voltage transformation by matrix converters (MC). The purpose - the further development of theory MC's control and development of new principles of switching an alternating current in them. Methods - theory of electric circuits, the method of Laplas continuous transformation, mathematical and physical modelling. Novelty - it is developed new methods of control and principles of safe switching the alternating current with association of features of algorithm of vector pulse-width modulation (VPWM) and step-by-step switching of bidirectional switches of MC, received analytical expressions for definition of adjusting coefficients which compensate influence of asymmetry of mains voltage on process of forming of the output voltage and input current of MC, defined conditions of minimization of switches' commutation in MC with VPWM, new method of compensation of subharmonics in the output voltage of MC with double-stage modulation is developed, conditions of transitions fromone scalar algorithm of MC's control to another with damping transients are formulated. Results - theory of control has received the further development and new principles of switching of the alternating current by bidirectional switches of MC for electric drives are developed. The carried out researches have found applications by development and introduction of MC in electric drives of turbomolecular pumps, sets for processing materials of electronic engineering etc. Area - designing of new frequency converters for speed control in AC electric drives.