Polishchuk S. Improvement of semiconductor converters EMC with mains electrical supply by controls and active filtering.

The object of research: The formation processes of the current consumed from the mains power supply by power semiconductor converters. The purpose of research: Increasing the level of EMC of semiconductor converters with network by means of creating new and improving existing control methods of semiconductor converters and with the help of active filtering of the currents consumed from mains power supply. Methods of research: The theory of differential equations and methods of mathematical physics, harmonic analysis and output voltage synthesis of the converters, elements of the matrix calculus and vector algebra, vector space theory, theory of electrical circuits, mathematical simulation and physical modeling of the formation processes of the current and voltage of converters. Theoretical and practical results and innovations: The concept of the back-to-back converter control has been proposed. It is based on a vector approaches to the formation of current consumed from the mains power supply. It allows to minimize the value of DC voltage link while ensuring the specified limits of regulation of the input power factor and input current quality indicators. Principles of matrix converters vector control have been improved by calculating the weighting coefficients and removal states, the calculated duration of which is less than the limit values, from structures of pulse-width modulation cycles. It is allowed to provide the adaptivity of the input current formation to the mains voltage unbalance and non sinusoidal conditions and improve the quality of the input current at the bottom of the range of output parameters. New coordinate systems for applications in the instantaneous power theory have been proposed and proved the feasibility of using. This allowed to implement the concept of constructing of adaptive coordinate system for the active filter control system and provide the control adaptation of the active filtering devices to the unbalance voltage power supply conditions with the help of organization of separate channel of the adjustment of the instantaneous reactive power component. The control strategy of shunt active filter in three-phase four-wire network at which instantaneous currents vector of three-phase network is proportional to the instantaneous phase voltages vector with partial attenuation of zero-sequence component has been proposed. The dependence of the required degree of the attenuation from the ratio of active resistances of phase and neutral conductors of the power cable network in order to minimize power losses in the power cable and improve the quality of current and voltage at the points of connection of the load to mains electrical supply has been determined. A subject and degree of implementation: The results of the research are used in the research projects of electrical Zaporizhzhya plant, in converters that have been put into practice at the "Knauf Gips Kyiv", "Rivneoblvodokanal", at the research institute of Mechanics Problems "Rhythm" in NTUU "KPI". Effectiveness of implementation: The possibility of obtaining the high performance input current. Sphere of use: enterprises of electrical engineering profile.