Sharma, D., Reghunath, S., and Athreya, A., "Dynamic Reserve Energy Storage for Hybrid Vehicle Fuel Economy Improvement," SAE Technical Paper 2015-26-0117, 2015, doi:10.4271/2015-26-0117.
The pressure of stringent emission norms and the need for reducing CO2 footprint has made Hybrid technology the need of future mobility.The viability of Hybrid heavily depends on the fuel economy margin it offers over the conventional powertrain. The advent of intelligent powertrain control strategies and optimization possibilities in the conventional powertrain arena tends to decrease the gap between the hybrid and conventional fuel economy.To retain the same fuel economy advantage over the intelligent conventional powertrain, hybrids need to have innovative and intelligent control strategies that optimize the energy balance between the ICE and E-machine without compromising the drivability and performance aspects of the vehicle.This paper explains an intelligent predictive control strategy for High Voltage Battery State of Charge of the parallel hybrid systems. Upcoming route terrain information is processed to analyse the future energy consumption pattern of the secondary power unit system (electrical system). Based on the secondary power unit characteristics, a dynamic equivalent energy reserve calculation is done.The activation and deactivation of the secondary power unit is decided based on continuous monitoring of the level of stored energy and the reserve calculation. This predictive secondary power unit disabling reserves the energy in the storage system for usage in the upcoming low demand torque route segments. This technique avoids IC Engine running in inferior efficiency regions, thereby increasing Fuel Economy.The maximum system torque remains unaffected even with this technique which will ensure that the performance and drivability parameters are unaffected. Simulations are conducted using Heavy Duty Truck model and Highway Route to assess the benefit of this technology.