Lebed D. Control system for power active filters in the presence of voltage fluctuations in distribution electrical networks

The dissertation work sets and solves the urgent task of improving the control system for power active filters to improve the quality of filtering higher harmonics and reduce voltage fluctuations in distribution electrical networks in the presence of rapidly changing and nonlinear loads. For the first time, the control laws of a parallel power active filter and a unified power quality regulator during voltage fluctuations have been established, taking into account their power limitations and requirements for voltage fluctuations, which ensures the selection of parameters for their control system. The control system of the parallel power active filter has been improved using adaptive adjustment of the integration time interval of the active and reactive components of the control current and the delay time of the control signals, which ensures high performance of the parallel power active filter. The control system of the unified power quality regulator has been further developed using a digital filter with a finite impulse response in the storage capacitor voltage control system, which ensures increased stability of the capacitor voltage under external disturbances. The practical significance of the obtained results is improvement and implementation of a control system for power active filters to reduce non-sinusoidality in the presence of voltage fluctuations in distribution electrical networks. Its application will contribute to improving the quality of electricity, in particular, reducing voltage fluctuations and non-sinusoidality in distribution electrical networks.