Search Results (3)

As the need for green and effective utilization of energy continues to grow, the advancements in the energy and power electronics industry are constantly driven by this need, as both industries are intertwined for obvious reasons. The developments in the power electronics industry has over the years hinged on the progress of the semiconductor device industry. The semiconductor device industry could be said to be on the edge of a turn into a new era, a paradigm shift from the conventional silicon devices to the wide band gap semiconductor technologies. While a lot of work is being done in research and manufacturing sectors, it is important to look back at the past, evaluate the current progress and look at the prospects of the future of this industry. This paper is unique at this time because it seeks to give a good summary of the past, the state-of-the-art, and highlight the opportunities for future improvements. A more or less ‘forgotten’ power electronic switch, the four-quadrant switch, is highlighted as an opportunity waiting to be exploited as this switch presents a potential for achieving an ideal switch. Figures of merit for comparing semiconductor materials and devices are also presented in this review. Full article

The research presented in this paper proposes a hybrid energy storage system that combines both electrolytic double-layer capacitors (EDLCs) also known as supercapacitors (SCs) and lithium-ion capacitors (LiCs) also known as hybrid capacitors (HCs) with a battery through a multiple input converter. The proposal was verified in simulation and validated by implementing a laboratory prototype. A new hybridisation topology, which reduces the amount of resource requirement when compared to the conventional hybridisation topology, is introduced. An electric vehicle (EV) current profile from previous research was used to test the performance of the proposed topology. From the results obtained, the hybridisation topology proposed in this research had the lowest cost per unit power at 14.81 $/kW, the lowest cost per unit power to energy, and available power to energy ratio, both at 1:1.3, thus making it a more attractive hybridisation topology than the two conventional alternatives. The multiple input converter built had efficiency values in excess of 80%. The key take away from this paper is that using the proposed hybridisation topology, the battery is less often required to supply energy to the electric vehicle, and so, its cycle life is preserved. Furthermore, since the battery is not used for the repeated acceleration and deceleration in the entire driving cycle, the battery’s cycle life is further preserved. Furthermore, since the battery is not the only storage device in the energy storage system, it can be further downsized to best fit the required base load; therefore, leading to a more optimized energy storage system by reducing the weight and volume of space occupied by the energy storage system, while also achieving better efficiencies. Full article

There has been increasing interests in the use of double layer capacitors (DLCs)—most commonly referred to as supercapacitors (SCs), ultra-capacitors (UCs), or hybrid capacitors (HCs)—in the field of power electronics. This increased interest in the hybridization of energy storages for automotive applications over the past few years is because of their advantage of high power density over traditional battery technologies. To facilitate accurate design and simulation of these systems, there is a need to make use of accurate and well validated models. Several models have been postulated in literature, however, these models have various limitations and strengths, ranging from the ease of use down to the complexity of characterization and parameter identification. The aim of this paper is to review and compare these models, specifically focusing on the models that predict the electrical characteristics of DLCs. The uniqueness of this review is that it focusses on the electrical circuit models of DLCs, highlighting the strengths and weaknesses of the different available models and the various areas for improvement. Full article