Input circuit analysis of 3 kv static converter in electric locomotives

W pracy zamieszczono analizę przekształtnika trakcyjnego DC/AC/DC z transformatorem pośredniczącym na napięcie 3 kV. Omówiono topologie układowe stosowane do tego typu zasilaczy oraz zawarto porównanie nowoczesnych materiałów magnetycznych wykorzystywanych do budowy transformatorów. Zaprezentowane zostały badania i wyniki symulacyjne typowych topologii przekształtnika DC/AC/DC zasilanego napięciem 3kV. W ramach potwierdzenia założeń teoretycznych przedstawiono wyniki badań zbudowanego przekształtnika DC/AC/DC o mocy 3 kW, 3x400 V.This paper presents analysis of 3kV DC/AC/DC converter with transformer. It also describes circuit topologies used for traction type of converters and also includes comparison of modern magnetic materials used in modern transformers. In addition author shows simulation results of typical converter 3kV DC. In order to check theoretical results the paper presents laboratory measurements of DC/AC/DC converter for 3kW, 3x400V

Digital signal registration of microprocessor controlled systems

W artykule zaprezentowano opis i budowę Rejestratora Przebiegów Cyfrowych. Dodatkowo omówiono programy komputerowe do rejestratora, pozwalające na zbieranie, obserwację i analizę danych z zewnętrznego układu mikroprocesorowego. Opisano również urządzenia pomocnicze wykorzystywane przy rejestracji danych.The paper presents description and architecture of a Digital Signal Registrator. The software for the registrator which allows us to receive, observe, and analyse the data from an external microprocessor device is described. Also auxiliary devices used for data recordimg are depicted

Auxiliary power converter with 3-level NPC structure for railway applications – simulation and experimental results

W artykule przedstawiono przetwornicę statyczną z izolacją transformatorową z wykorzystaniem struktur wielopoziomowych typu NPC (ang. Neutral Point Clamped). Zaprezentowano wybrane wyniki badań symulacyjnych i laboratoryjnych przekształtnika AC/DC i DC/AC w topologii 3-poziomowej.The paper presents AC/DC/AC converter with galvanic isolation of NPC (Neutral Point Clamped) multilevel structures. Selected simulation and experimental results of 3-level AC/DC/AC converter are presented

Comparative study between two-level and three-level high-power low-voltage AC-DC converters

The article presents the analysis of the simulation test results for three variants of the power electronics used as interface between the power network and superconducting magnetic energy storage (SMES) with the following parameters: power of 250 kW, current of 500 A DC and voltage of 500 V DC. Three interface topologies were analyzed: two-level AC-DC and DC-DC converters; three-level systems and mixed systems combining a three-level active rectifier and a two-level DC-DC converter. The following criteria were considered: input and output current and voltage distortions, determined as THDi and THDu, power losses in power electronics components; cost of the semiconductor components for each topology and total cost of the interface. Results of the analysis showed that for high-power low-voltage and high-current power electronics systems, the most advantageous solution from a technical and economical perspective is a?two-level interface configuration in relation to both AC-DC and DC-DC converters

Selected converter topologies for interfacing energy storages with power grid

The paper presents different solutions applicable in power converter systems for connecting power grids with energy storage systems such as superconducting magnetic energy storage (SMES), supercapacitor energy storage (SES) or chemical batteries. Those systems are characterized by bidirectional current flow between energy storage and power grid. Two-level converters (AC-DC and DC-AC converters) dedicated for low power energy storage compatible with 3×400 V-type power grids are proposed. High power systems are connected with 3×6 kV-type power grids via transformers that adjust voltage to the particular energy storage or directly, based on multilevel power converters (AC-DC and DC-AC) or dual active bridge (DAB) systems. Solutions ensuring power grid compatibility with several energy storage systems of the same electrical parameters as well as of different voltage-current characteristics are also proposed. Selected simulation results illustrating operation of two system topologies of 200 kW power for two-level converter and neutral point clamped (NPC) three-level converter are presented