Rule-based assistive hybrid electric brake system with energy generation for electric vehicle

ABSTRACT

One of the benefits of increased penetration of EVs is their ability to generate energy during braking operations. Electrochemical batteries are the most commonly used storage devices in EVs to propel electric motors. However, the large charging current generated during regenerative braking adversely affects the life of battery and hence the motor fails to produce maximum brake torque. The supercapacitor is employed in EVs because of its high power density and effectively contributes during braking operation. However, the supercapacitor also suffers from an aging and hence braking torque generated reduces after usage. This article proposes a blended brake system for EVs in which a dynamic brake resistor is added with a supercapacitor to increase the rate of energy absorption during braking. This addition of a dynamic braking mechanism provides assistive braking torque so that the motor’s braking torque production capability increases. The system is controlled with a rule-based controller, and it is tested with ECE and IM240 drive cycles. This method is 3.3% efficient in reducing the speed of the motor compared to the conventional regenerative braking approach. Moreover, the intervention of supercapacitor increases energy recovery by 3% and 5.88% for ECE and IM240 test cycles, respectively.

KEYWORDS:

• Electric vehicle
• regenerative braking
• blended braking
• rule-based controller
• brake dust emission

Disclosure statement

No potential conflict of interest was reported by the author(s).