Innovative bidirectional isolated high-power density on-board charge for vehicle-to-grid

This paper deals with developing and implementing a bidirectional galvanically isolated on-board charger of a high-power density. The power density of the new charger was 4 kW/kg and 2.46 kW/dm(3), and the maximum efficiency was 96.4% at 3.4 kW. Due to the requirement to achieve a high-power density, a single-stage inverter topology was used. Regarding switching losses, due to the topology of the circuit with so-called hard switching, the switching frequency was set to 150 kHz. A laboratory prototype was built to verify the properties and operating principles of the described charger topology. The on-board charger has been tested in a microgrid test platform. Due to the parasitic properties of the transformer and other electronic components, overvoltage with subsequent oscillations occurred on the primary side of the transformer and damped resonance on its secondary side. These parasitic properties caused interference and especially voltage stress on the semiconductor elements. These undesirable phenomena have been eliminated by adding an active element to the charger topology and a new transistor control strategy. This new switching control strategy of transistors has been patented.Web of Science2221art. no. 847

Nová metoda přímého řízení momentu asynchronního motoru s použitím DSP

Import 20/04/2006Prezenční výpůjčkaVŠB - Technická univerzita Ostrava. Fakulta elektrotechniky a informatiky. Katedra (448) výkonové elektroniky a elektrických pohon

Metody přímého řízení momentu asynchronních motorů

Import 30/07/2008Prezenční448 - Katedra elektronikyNeuveden

Smart grid energy system operation study

Energy systems which combine renewable energy sources and waste-to-energy systems have been of great interest around the world. These systems use eco-friendly technologies and reduce waste production, which are the emerging priorities of the European Union. This paper describes an experimental hybrid energy system installed in the Technology Centre of Ostrava (TCO) at VSB-Technical University of Ostrava consisting of a solar photovoltaic system, fuel cell technology, pyrolysis unit, cogeneration unit, power converters and battery packs. These components form a system able to produce electricity to power our facilities or to be supplied into the electrical grid with financial profits. The experimental operation was carried out to determine a real electricity yield. The fuel for the pyrolysis unit was ground tyres, as common waste with high combustible gas components, which is suitable for cogeneration unit operation. In a 24-h operation mode, there was 1280 kWh of electricity supplied to the power grid, but if we take into consideration all energy inputs into the system and only electricity production as output, the efficiency was only 9%.Web of Science145art. no. 4