Performance of Virtual Torque Sensor for Heavy Duty Truck Applications
2022-01-0754
03/29/2022
- Event
- Content
- Automotive Companies are constantly looking to increase the fuel efficiency, shift quality, passenger comfort, and to reduce wear and tear on the components. Torque is one of the parameters that is estimated using SAE J-1939 CAN bus algorithm. This estimated torque is used for transmission control and to determine the required operational gear position at a given speed and road conditions. Currently, SAE J-1939 CAN bus torque estimation relies on steady state maps that are generated during the calibration of engine for different speeds and loads. The accuracy of the estimated torque is affected by the transient events like hill climbing, changing on-road traffic situations etc. which results in poor shift control causing higher fuel consumption. In this paper we report the development of a Virtual Torque Sensor (VTS) useful for real time torque measurement based on the engine harmonics analysis. The VTS uses the signal from the flywheel speed sensor to estimate the nth order flywheel angular acceleration, which provides a proportional torque value. The performance of the VTS is evaluated using an engine with flywheel attached to a dynamometer at different torque loads (0-100% load) and different speeds (900-2000 RPM). The accuracy of the sensor is found to vary from 2% to a maximum of 12% for 100% load test. The observed torque variation is linear within the speed range tested for medium (≥50%) load conditions and is in agreement with standard strain gauge-based measurement. The dynamometer test results are validated using 1D AMESim engine modeling and simulation.
- Citation
- Iddum, V., Chahal, I., Bair, J., and Ghantasala, M., "Performance of Virtual Torque Sensor for Heavy Duty Truck Applications," SAE Technical Paper 2022-01-0754, 2022, .