The high power density capability of Ultracapacitor (UC) can be utilized by developing of Hybrid Energy Storage System (HESS) with a conventional power source, battery. UC power mainly used during peak power requirement of electric vehicle (EV) / Hybrid electric vehicle (HEV) on the other hand side battery is treated as a main source of the entire system and it serves the average power to the load. Energy management between the sources, is the primary difficulty associated with HESS powered electric vehicles. The main aim of this work is to design a new control strategy approach which is used to switch the power sources according to the electric vehicle dynamics. Four math functions are created individually according to the speed of an electric motor, named as Math Function Based (MFB) controller. The designed MFB controller is combined with a Proportional Integral (PI) controller in order to achieve the main objective and applied to the solar-powered electric vehicles for a smooth transition between battery and UC. The principal goal of the designed MFB controller always regulates the pulse signals generated by the conventional PI controller, and this scenario happens with respect to the speed of an electric motor. A solar panel is connected to the electric vehicle which is used to charge the battery charge based on irradiance, temperature available conditions and discharge the same amount of energy during unavailable timings of sunlight All modes of the circuit is simulated in MATLAB and results are plotted, discussed in simulation results and discussion section.
solar power, Hybrid Electric Vehicles (HEVs), Bidirectional Converter (BDC), Unidirectional Converter (UDC), battery, ultracapacitor, Math Function Based (MFB) controller, Proportional Integral (PI) controller
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