Evaluating the entire system as opposed to components individually leads to fully optimised solutions
Leamington Spa, UK, 11th September 2018 – A novel simulation and analysis tool will optimise the design of electric vehicle powertrains, significantly improving cost, performance and packaging. Developed by leading driveline engineering consultancy Drive System Design (DSD), the tool enables the multi-disciplinary analysis of the system as a whole, evaluating the sub-system trade-offs to deliver an optimum solution.
“You can use the best inverter, motor and transmission available on the market, but if they don’t work well together the solution won’t be the best it could,” said Dr Michael Bryant, Principal Engineer, Drive System Design. “To optimise an electric powertrain you must consider the system as a whole. Our tool enables us to accurately analyse thousands of potential concepts in just a few hours, which importantly aren’t affected by personal preferences. It significantly reduces the time and cost in developing and evaluating concepts and ultimately leads to a better solution.”
For example, the use of a downsized motor with higher rotor speed and reduced mass has a direct impact on the other components. The inverter will require a higher switching frequency to handle the speed increase, which may in turn reduce efficiency and could potentially add cost. The lower torque from the motor will necessitate a higher ratio in the transmission, increasing mass and reducing efficiency. DSD’s tool will analyse these trade-offs to determine if the motor choice benefits the system and the vehicle.
The process has been developed in-house and validated against measured test data to ensure correlation with physical systems. By considering the vehicle manufacturer’s targets, such as the performance required and typical user drive cycles, the design direction of an electrified powertrain can be efficiently decided.
“Traditionally, electrified powertrain sub-systems, such as the motors and inverters, have been considered and designed individually, often by different companies, in different countries, using different pieces of software,” continues Dr Bryant. “We believe the use of our tool will result in optimised powertrains, reducing size, weight and cost, and increasing efficiency compared to traditional methods. Ultimately the optimisation potential of such a system will ensure that the battery, a key component for cost and weight, can also be minimised.”
Dr Bryant will be presenting a paper on the analysis tool, including example results, at the 2018 CENEX Low Carbon Vehicle Event at Millbrook, 12-13th September. The paper, titled “Gearing up for lower cost electric drives – Novel methods for analysing integrated electric powertrains”, will be presented on day 1 at 16:20 in the Main Plenary Hall as part of the ‘Power Electronics, Machines and Drives’ session.
Interviews at the Low Carbon Vehicle show
DSD will be present at the Low Carbon Vehicle Show (Millbrook, UK, September 12-13). If you would like to arrange an interview with Dr Bryant, please call the press contact Richard Doherty on 07810 774105.
Drive System Design (DSD) is an award winning engineering consultancy specialising in the engineering, development, test and control of electrified and conventional driveline systems.
The company’s staff have experience working with vehicle manufacturers and Tier 1s around the world, designing new technologies and solving problems to make their products more competitive. They have the engineering, test, analysis and project management skills necessary to deliver projects to demanding timescales. Working closely with its customers through technical centres in Europe and North America, DSD is recognised as a world leading expert in driveline refinement, efficiency improvement and hybrid and electric vehicle transmissions. DSD is ISO 9001 and ISO 14001 certified.