Automated engine calibration validation for real world driving conditions

With the introduction of the Worldwide Harmonised Light Vehicles Test Procedure (WLTP) and Real Driving Emissions (RDE) legislative tests, it has become imperative for automotive manufacturers to verify that their vehicles operate reliably and efficiently across a wide range of operating conditions. Engine air charge control and torque delivery should be consistent, smooth, and predictable to the operator, despite disturbances induced by technologies designed to improve efficiency and reduce emissions such as Variable Cam Timing (VCT), Exhaust Gas Recirculation (EGR) and forced induction. This is of particular importance to hybrid and Advanced Driver-Assistance Systems (ADAS)-enabled vehicles which require accurate control of the engine torque. The torque strategy validation is an iterative process which can be very time-consuming, expensive and requires considerable experience in order to adjust the calibration to meet validation requirements whilst maintaining accuracy with regards to the original characterisation data. This paper describes development and introduction of an automated validation process at the Ford’s Dunton Technical Centre in the UK. The algorithm was developed and tested in conjunction with a co-simulation environment, and both simulated and experimental results are presented. The automated procedure has been shown to reduce validation process time by around 50% resulting in significant cost saving whilst improving the overall accuracy of the calibration by around 30-50% depending on the engine programme.