Duncan Nicoll

A Study of the Impact that Induced and Leakage Electrical Current have on Rolling Contact Fatigue of Motor Bearings in Electric Vehicle

Supervisors – Dr Ling Wang, Prof Andrew Cruden

nCATS Research Group

I am a graduate of the University of Sussex, where I completed an undergraduate and Masters in Mechanical Engineering. Following this I spent two years working within the aerospace industry, specifically fuel delivery systems and centrifugal pump design. I returned to Academics to pursue a Phd in a developing field. Looking at Electric Vehicle as a rapidly growing industry and a crucial step for society to move towards being carbon neutral. My project looks to resolve a long-standing limitation to the effectiveness of electric drives, by reducing bearing failure rate, making them more economically viable for manufacturers and users alike.

Project Funders: Engineering and the Environment Research Studentship within the Faculty of Engineering and Physical Sciences

Project details: 

My research “A Study of the Impact that Induced and Leakage Electrical Current have on Rolling Contact Fatigue of Motor Bearings in Electric Vehicle” focuses on expanding on the current understanding of the phenomena related to electric bearing currents within electric motor drives and how this impacts the bearing life. The fundamentals of the phenomena is that leakage electrical currents are induced on the rotor drive from asymmetries in a induction motor. These currents then circulate across the motor housing bearings through the frame, across the alternate end bearings and back to the rotor shaft. The impact is electrical discharge between the raceways and rolling elements within the bearing, leading to an increase in rolling contact fatigue and premature failure. The aim of my research is to improve predictability of this occurrence. Defining what voltage and current levels result in particular failure modes and then propose possible solution to prevent the phenomena from happening.