Model Validation of the Chevrolet Volt 2016 2018-01-0420
Validation of a vehicle simulation model of the Chevrolet Volt 2016 was conducted. The Chevrolet Volt 2016 is equipped with the new “Voltec” extended-range propulsion system introduced into the market in 2016. The second generation Volt powertrain system operates in five modes, including two electric vehicle modes and three extended-range modes. Model development and validation were conducted using the test data performed on the chassis dynamometer set in a thermal chamber of Argonne National Laboratory’s Advanced Powertrain Research Facility. First, the components of the vehicle, such as the engine, motor, battery, wheels, and chassis, were modeled, including thermal aspects based on the test data. For example, engine efficiency changes dependent on the coolant temperature, or chassis heating or air-conditioning operations according to the ambient and cabin temperature, were applied. Second, the vehicle-level control strategy was analyzed under normal ambient temperature conditions for both charge-depleting and charge-sustaining modes. Next step, the effect of thermal conditions, such as ambient temperature or vehicle initial states (soaked or warmed-up vehicle), on the vehicle-level control strategy was analyzed. Operation of the heater, in particular, affects the vehicle-level control strategy, depending on the engine coolant temperature or heating demand. Finally, the entire vehicle model, including the vehicle-level controller, was implemented into Autonomie, a high-fidelity, forward-looking vehicle simulation tool. As a result, discrepancies in fuel economy were shown to be within 5%, as in most cases in the test-to-test variability, while many of the operational signals, including state of charge of the battery, were well matched.