Search

This study highlights the critical role of maintaining high power quality in autonomous grids, particularly in complex systems with significant non-linear loads, such as shipboard power systems. Power quality issues such as voltage harmonic distortion and imbalance can lead to serious malfunctions and even accidents. This paper proposes an advanced predictive control algorithm with feedback from the supply current developed for a shunt active power filter. The presented control algorithm is characterized by high effectiveness in compensating supply current harmonics, imbalance, and reactive power, thereby improving power quality. This high performance in executing compensation tasks has been confirmed through experimental tests conducted in an autonomous grid powered by a diesel generator. The research results also include the system's adaptability under varying load conditions, the impact of delays, and the converter's non-linearities on the operation of the active power filter. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nowadays, the use of power converters to control active and reactive power in AC−AC grid-connected systems has increased. With respect to indirect AC−AC converters, the tendency is to enable the back-to-back (BTB) voltage source converter (VSC) as an active power filter (APF) to compensate current harmonics. Most of the reported works use the BTB-VSC as an auxiliary topology that, combined with other topologies, is capable of active power regulation, reactive power compensation and current harmonic filtering. With the analysis presented in this work, the framework of the dynamics associated with the control loops is established and it is demonstrated that BTB-VSC can perform the three tasks for which, in the reviewed literature, at least two different topologies are reported. The proposed analysis works to support the performance criteria of the BTB-VSC when it executes the three control actions simultaneously and the total current harmonic distortion is reduced from 27.21% to 6.16% with the selected control strategy.

This paper analyzes and proposes technical considerations for the selection and design of passive filter schemes rated at several mega VARs to compensate reactive power and current harmonics in mining power distribution systems. The paper includes technical information and analysis required to select the most adequate passive filter topology, to select the tuning frequency for each unit, to calculate filter parameters, and to distribute reactive power between passive filters. Passive filter schemes analyzed in this paper are used to compensate mining power distribution systems, especially when high-power grinding mill drives energized from 12-pulse cycloconverters are used in conjunction with several other nonlinear loads. This paper also analyzes technical limitations that passive filters present in the attenuation of low-frequency current harmonics. Finally, two power distribution systems with different passive filters schemes are evaluated, and the limitations in the attenuation of low-frequency current harmonics generated by cycloconverters are demonstrated with measured results. [ABSTRACT FROM AUTHOR]

Nowadays, the use of power converters to control active and reactive power in AC–AC grid-connected systems has increased. With respect to indirect AC–AC converters, the tendency is to enable the back-to-back (BTB) voltage source converter (VSC) as an active power filter (APF) to compensate current harmonics. Most of the reported works use the BTB-VSC as an auxiliary topology that, combined with other topologies, is capable of active power regulation, reactive power compensation and current harmonic filtering. With the analysis presented in this work, the framework of the dynamics associated with the control loops is established and it is demonstrated that BTB-VSC can perform the three tasks for which, in the reviewed literature, at least two different topologies are reported. The proposed analysis works to support the performance criteria of the BTB-VSC when it executes the three control actions simultaneously and the total current harmonic distortion is reduced from 27.21% to 6.16% with the selected control strategy. [ABSTRACT FROM AUTHOR]