Two-mode hybrid architectures with three planetary gear sets and four clutches will bring both flexibility and complexity to energy management of powertrains. In order to take full advantage of the increased degrees of freedom, highly delicate operation strategies are needed. Presented are basic concepts for developing mode shift strategies. Some important considerations, which could not be included here, can be contained in further research. Precise models of motor control losses and actuator losses will allow fairer and more realistic comparison between mode operation results. Additional attention should be paid to the transient responses. This is to prevent the strategies from deteriorating shift quality and from providing inefficient or infeasible operation commands to the components. The findings are summarized below: 1. The transmission efficiency of an EVT (Electrically Variable Transmission) is determined by the input speed, input torque and the speed ratio. Especially, the speed ratio is the most decisive factor. 2. The optimal trade-off between the engine and the transmission efficiencies could determine the optimal mode when the battery operation is limited. 3. The POP analysis applied to the two-mode, three- PG system could define the best mode corresponding to battery power. This yielded different results from the strategy for no battery power. 4. The addition of fixed gear operations is beneficial from the viewpoint of fuel economy. For considerable output load conditions, the FG (Fixed Gear) modes were the most efficient choices. 5. Dynamic optimization and the optimal shift algorithm showed that the actual mode shift comprises the base strategy for no battery power and its variations for light battery operation.
Developing mode shift strategies for a two-mode hybrid powertrain with fixed gears
Entwicklung von Mode-Shift-Strategien für einen Zweibetriebsarten-Hybridantriebsstrang mit feststehenden Getrieben
2008
8 Seiten, 13 Bilder, 2 Tabellen, 9 Quellen
Aufsatz (Konferenz)
Englisch
Developing Mode Shift Strategies for a Two-Mode Hybrid Powertrain with Fixed Gears
British Library Conference Proceedings | 2008
|Developing Mode Shift Strategies for a Two-Mode Hybrid Powertrain with Fixed Gears
SAE Technical Papers | 2008
|Developing mode shift strategies for a two-mode hybrid powertrain with fixed gears
Kraftfahrwesen | 2008
|2008-01-0307 Developing Mode Shift Strategies for a Two-Mode Hybrid Powertrain with Fixed Gears
British Library Conference Proceedings | 2008
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