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O. Krievs and L. Ribickis

Frequency Selective Control of a Parallel Active Filter with Resonance Filter Regulators

The paper describes a method for frequency selective control of parallel active filters that are applied for compensation of the current harmonic distortions and the displacement power factor in symmetrical three-phase systems with a known harmonic spectrum. For simulation, an active filter for harmonic current compensation of a three-phase full-bridge diode rectifier was used. Comparative analysis has shown a good agreement between the results obtained experimentally and by simulation

Open access

P. Suskis, A. Andreiciks, I. Steiks, O. Krievs and J. Kleperis

Abstract

The authors propose a micro-grid for autonomous wind-and-hydrogen power generation thus replacing such traditional fossil-fuelled equipment as domestic diesel generators, gas micro-turbines, etc. In the proposed microgrid the excess of electrical energy from a wind turbine is spent on electrolytic production of hydrogen which is then stored under low-pressure in absorbing composite material. The electrolyser has a non-traditional feeding unit and electrode coatings. The proposed DC/DC conversion topologies for different micro-grid nodes are shown to be well-designed. The prototypes elaborated for the converters and hydrogen storage media were tested and have demonstrated a good performance.

Open access

A. Andreičiks, I. Steiks and O. Krievs

Abstract

In domestic applications the low DC output voltage of a hydrogen fuel cell used as the main power supply or a backup power source has to be matched to the level and frequency of the AC voltage of utility grid. The interfacing power converter system usually consists of a DC/DC converter and an inverter. In this work, a DC/DC step-up converter stage is designed for interfacing a 5kW proton exchange membrane (PEM) fuel cell. The losses of DC/DC conversion are estimated and, basing on the relevant analysis, the most appropriate configuration of converter modules is selected for a DC/DC converter stage of increased efficiency. The authors present the results of experimental analysis and simulation for the selected configuration of four double inductor step-up push-pull converter modules