Exergetic performance improvement by a novel energy management with fault tolerance in a fuel cell based hybrid electric vehicle

Nowadays, the use of green energy is becoming increasingly important. For this reason, environmentally friendly hybrid electric vehicles with low CO2 emissions are preferred. The low range problem of battery electric vehicles and the emission emission of hybrid vehicles not being at the desired level have increased the popularity of fuel cell vehicles. These vehicles, whose primary energy source is a fuel cell, are used with batteries and supercapacitors in order to increase system performance. Fuel cell + battery, fuel cell + supercapacitor and all of together are classified as the most popular topologies. With the combined use of these energy storage systems, an energy management system is needed to ensure correct and efficient power distribution. The efficient use of energy is provided by exergy management. At the same time, fault-tolerant systems are needed to ensure the reliability and continuity of fuel cell vehicles. In this thesis, fuel cell + battery, fuel cell + supercapacitor and fuel cell + battery + supercapacitor topologies were created. UDDS, HWFET, WLTP and FTP driving cycles were applied to these topologies. Power follower control strategy and fuzzy logic control strategies, which are among the energy management strategies, were applied to each topology and fuel consumption, power performance, energy efficiency comparisons were made for each driving cycle. The losses that cannot be detected in energy analysis are determined with exergy analysis. Therefore, both energy and exergy analyses were performed in this thesis study. Exergy efficiencies and losses were examined in detail in three topologies under the fuzzy logic control strategy and power follower control strategy. At the same time, reliable and uninterrupted operation is very important in fuel cell vehicles. Due to the complexity of the system, fault tolerance is important in order not to disrupt the continuity of the system in possible faults and to continue the operation of the vehicle. For this reason, the reactions of the system according to fault scenarios were examined in this thesis study. This thesis aims to contribute to the wider application areas of fuel cell vehicle technology and the development of sustainable and efficient vehicles.