Student Research Highlight: Acceleration-Based Design of Electric Vehicle Auxiliary Energy Source Aree Wangsupphaphol, Nik Rumzi Nik Idris, Universiti Teknologi Malaysia, Skudai, Johor, Malaysia DOI. No. 10.1109/TAES.2016.140011. PROBLEMS BACKGROUND AND AIMS The battery electric vehicle (BEV) has disadvantages of high power loss during acceleration and poor regenerative braking energy recapture. Moreover, the battery is frequently exposed to repetitive high power demand, which consequently short- ens the battery lifetime [1]. To overcome these problems, many parallel connections of energy sources have been proposed by scientists with the aim to reduce high peak power supply and repetitive power, as well as to save battery energy and lengthen its use [2], [3]. In this article, a parallel supercapacitors (SCs)- batteries scheme for battery hybrid electric vehicle (BHEV) and its control are proposed. The confguration consists of a parallel connection of batteries and SCs, which are connected to the in- verter via a bidirectional dc-dc converter, as shown in Figure 1. This scheme intends to save braking energy for extending the driving range. In order to control the voltage and current of SCs, the control algorithms, composed of cascaded voltage and current loops based on the acceleration-based design (ABD), are developed. For effciency validation, comparison of the core features between 3 different system confgurations are proposed: the proposed BHEV with acceleration-based design (BHEV-ABD), BHEV with load-based design (BHEV-LBD) [4], and a pure BEV. PAST RESEARCH AND CURRENT STATE OF ART Currently, the major problem of control strategy, as reported in the literature, is obtaining a proper real-time SCs current refer- ence. A too high set point means the SCs are fully discharged even before the end of the acceleration phase, with consequence of high battery voltage variation and losses. On the other hand, a too low reference will incur poor utilization of SCs [5]. In [4], the authors proposed a real-time state of charge (SoC) control of SCs by using LBD and optimal neural network (NN) control. The energy consumption evaluation for a city driving cycle in simulation shows that the BHEV-LBD consumed more energy than the BHEV with NN control. In case of BHEV-LBD, the SCs voltage reference was generated by the SoC look-up table, and the SCs current reference was produced by the wideband current limiter; hence, proper real-time references could not be achieved due to nondynamic properties of the control algo- rithms. On the other hand, the NN control has the disadvantages of requiring a precise knowledge of the driving cycles for the training; otherwise, the optimal solution could not be realized. Moreover, in order to implement the NN-based control, a high performance processor is required thus increasing the cost of the vehicle. In this article, a simple yet effcient acceleration- based design for SCs is proposed. The proposed control system is capable of generating proper real-time SCs voltage and cur- rent references simultaneously, thus improving the overall per- formance of the BHEV. CONTRIBUTION The contribution of the proposed rule-based control strategy is the generation of proper real-time references for the SCs’ voltage and current of electric vehicle applications. Since the rule-based strat- Authors’ address: UTM-PROTON Future Drive Laboratory, Universiti Teknologi Malaysia, Skudai, Johor 81310 Malaysia, E-mail: (areeceic@yahoo.com). This research is supervised by N. R. N. Idris, A. Jusoh, N. D. Muhamad, Department of Electrical Power Engineering, Fac- ulty of Electrical Engineering, Universiti Teknologi Malaysia. Manuscript received January 23, 2015; revised February 12, 2015, April 5, 2015, October 7, 2015; ready for publication October 9, 2015. Refereeing of this contribution was handled by J. Glass. 0885/8985/16/$26.00 © 2016 IEEE Figure 1. The confguration of the proposed parallel SCs-batteries hybrid electric vehicle. 32 IEEE A&E SYSTEMS MAGAZINE JANUARY 2016