This paper describes the high efficiency drive unit for an EV, which is designed with accessible solutions for the efficiency increasing. Synchronous utilization of ultracapacitors and three-level inverter brings considerable power savings and enhancement longevity for a lithium battery pack. The total loss and EMI comparison between the two-level and three-level inverter and power measurements on the EV drive unit are presented at the conclusion part of this paper.

This paper focuses on the development and optimization of a special hybrid electric vehicle arrangement known as a four-quadrant rotary converter. The introduction summarizes the main advantages and disadvantages of existing topologies in radial and axial flux arrangements. Based on previous experience, we developed a novel axial flux arrangement that eliminates the problems and disadvantages associated with existing radial flux solutions. In addition, this paper evaluates and subsequently describes the optimization of permanent magnet parameters in an axial flux rotary converter unit. A number of 3D finite element method optimizations were performed to find the optimal mass distribution of permanent magnets on the frontal area of the outer rotor in the axial flux rotary converter unit. The optimization involved the permanent magnets’ material, shape, and thickness in order to achieve maximal efficiency of the entire unit while leaving its nominal output power and speed unaffected. The results show an increase in the overall theoretical efficiency of the outer rotor unit from 90.2% to 94.4% following the optimization.

Control of electrical power systems with attached units of accumulation represents a relatively complex problem, both in terms of technical equipment and in terms of the measurement and the control algorithms. In order to control system dynamically from the viewpoint of energy flows, so particularly with regard to increasing quality of electrical energy, all processes must be processed with relatively high frequency of sampling. The paper describes the elements of electrical energy accumulation control system, which was implemented in the Technology Centre of VřB - Technical University of Ostrava. This system uses originally developed analog measuring logger, which performs data collection from the entire system, processes the data and generates the desired quantity of them for semiconductor converters control. These converters perform control of energy flows throughout the accumulation system.

Comparison of Standard and Fast Charging Methods for Electric Vehicles

The searching and utilization of new energy sources and technologies is a current trend. The effort to increase the share of electricity production from renewable energy sources is characteristic for economically developed countries. The use of accumulation of electrical energy with a large number of decentralized storage units is most preferred, as well as the focus on the production of energy at the point of its consumption. Modern cogeneration units are a good example. This paper describes the accumulation of electrical energy for equalizing the power balance of electric charging stations with high instantaneous power. The possibility of re-utilization of electrical energy from the charged vehicle in the case of lack of electricity in the power grid is solved at the same time. This paper also deals with the selection of appropriate concept of accumulation system and its cooperation with both renewable and distribution networks. Details of the main power components including the results obtained from the system implementation are also described in this paper.