Controls Development for Clutch-Assisted Engine Starts in a Parallel Hybrid Electric Vehicle



SAE 2011 World Congress & Exhibition
Authors Abstract
In a parallel hybrid electric vehicle, higher fuel economy gains are typically achieved if significant electric drive (or engine-off) operation is possible, shifting the engine operating schedule so that it only runs at medium to high load for best efficiency. To enable efficient engine-off driving, a typical configuration will have a disconnect clutch between the engine and the rest of the driveline. In some configurations, when engine-on operation is requested the disconnect clutch is applied in conjunction with the traction motor/generator to crank the engine (i.e., a flying engine start). In this paper we describe the development of a control system for a flying engine start using an engine disconnect clutch. The clutch is located between the engine and electric motor, which is connected to the input of a multispeed transmission. We first describe an initial control algorithm evaluation using a driveline model. After this initial evaluation, the control algorithm was incorporated into an existing hybrid vehicle control system architecture and tested on a HIL bench to validate code implementation. Finally, we describe experiments in which we tested the control algorithm in a test cell using a mule transmission. We discuss in qualitative terms the refinements in the control algorithm resulting from the experimental results.
Meta TagsDetails
Smith, A., Bucknor, N., Yang, H., and He, Y., "Controls Development for Clutch-Assisted Engine Starts in a Parallel Hybrid Electric Vehicle," SAE Technical Paper 2011-01-0870, 2011,
Additional Details
Apr 12, 2011
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Content Type
Technical Paper