This paper focus on a novel operation of a brushless dc (BLDC) motor fed by a proportional integral (PI) controlled buck--boost converter supplemented with a battery to provide the required power to drive the BLDC motor. The operational characteristics of the proposed BLDC motor drive system for constant as well as step changes in dc link voltage of a front end converter controlled by a Xilinx System Generator (XSG) based PI controller for two quadrant operations are derived. Thus a field programmable gate array (FPGA) based PI controller manages the energy flow through the battery and the front end converter. Moreover, speed to voltage conversion logic, made to control the BLDC motor through the PI controller, improves the performance and gives optimum control under the unstable driving situation or varying load condition when the complete system becomes a subject of application to electric vehicles (EVs) and hybrid electric vehicles (HEVs). The dual closed loop control implemented for end to end speed control of the proposed drive system facilitates the system with high accuracy integrated with excellent dynamic and steady state performance. In this paper, the proposed controller was designed for a 5 kW/480 V BLDC motor drive system. The feasibility of the proposed dual loop control topology for the BLDC motor drive system is validated and verified with extensive dynamic simulation in MATLAB/SIMULINK and XSG environment.