Contents I. Introduction
The ever increasing demand of the fossil fuels and growing level of pollution in the case of conventional internal combustion engine (ICE) vehicles has led to the commercialization of the electric vehicles. The fuel cell electric vehicle not only have comparable performance with ICE based vehicle but also have better overall efficiency because the fuel cell allows the direct conversion of compressed hydrogen and oxygen from the air to generate the electricity (without any combustion) [1], [2]. The byproduct produced during this reverse electrolysis process is the water and heat which can be easily expelled. Thus fuel cell is the clean energy source as absolutely less or zero greenhouse gas emission takes place. However this fuel cell has certain demerits: it possess less power density compared to ICE, poor dynamic response thus cannot provide the sudden peak power. The fuel cell cannot absorb the regenerative braking energy thus resulting in the more fuel consumption (i.e. hydrogen) [3]. Hence the need of hybridization of fuel cell with the battery and supercapacitor is necessary [4]. These auxiliary energy sources reduce the stress on the fuel cell during the sudden peak power demands at time of acceleration and absorb the power during braking, thus results in less fuel consumption and improved lifetime of fuel cell [5], [6], [7]. Hence the energy management strategy is required to control these hybrid energy sources [8]-[14].
