Hybrid Drive Torque Coordination via Electric Machine Mediator
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for dynamic torque coordination in hybrid vehicle drives lack an overall concept to achieve specified total target torque with high dynamics across a wide operating range while considering fuel consumption, exhaust emissions, and service life of drive units.
Innovation Solution
The method involves operating drive units at ideal or approximately ideal operating points, with one unit providing dynamic torque and/or speed compensation to achieve total target torque and speed, and switching between multiple operating modes to fully utilize the hybrid drive's working range, prioritizing modes based on efficiency, emissions, and wear considerations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the internal combustion engine is operated at an efficiency-optimal operating point with a lead setpoint torque, then fuel efficiency is improved, but the dynamic response speed deteriorates due to finite setting speed of the throttle flap and intake manifold filling effects
Solution Approach 1:
The electric machine acts as an intermediary between the driver's torque demand and the internal combustion engine. It can rapidly adjust its torque output to compensate for the slow dynamic response of the IC engine, while the IC engine operates at its efficiency-optimal point with a lead setpoint torque. This mediator approach allows the hybrid system to achieve both high fuel efficiency and fast dynamic response.
Solution Approach 2:
The system dynamically changes the operating parameters of the electric machine (torque, speed) to compensate for the fixed efficiency-optimal operating point of the internal combustion engine. By adjusting the electric machine's torque contribution in real-time, the system maintains overall high efficiency while achieving fast dynamic response to varying torque demands.
2Speed
If the electric machine is used to implement temporary torque requirements, then dynamic response is improved, but the overall concept to implement specified total target torque with high dynamics in a wide operating range while considering fuel consumption, exhaust emissions and service life deteriorates due to lack of comprehensive coordination
Solution Approach 1:
The system dynamically switches between different operating modes (first operating mode with IC engine at efficiency-optimal point, second operating mode with other drive unit at ideal operating point) based on real-time operating conditions. This dynamic mode selection allows the system to adapt to varying torque demands, efficiency requirements, emissions constraints, and service life considerations across the entire operating range, providing comprehensive coordination without excessive complexity.
Solution Approach 2:
The control system is designed to universally handle multiple objectives simultaneously: fuel consumption optimization, emissions reduction, service life extension, and high-dynamic torque implementation across the entire operating range. By creating a unified control concept that can operate in multiple modes and consider all these factors together, the system achieves comprehensive coordination for the hybrid drive.
3Device complexity
If the hybrid drive operates in a limited operating range, then control simplicity is improved, but the working range utilization deteriorates
Solution Approach 1:
The system dynamically adapts its operating mode based on the current operating point within the hybrid drive's working range. By implementing mode switching logic that activates different operating modes based on real-time conditions (torque demand, speed, efficiency requirements), the system can utilize the entire working range while maintaining relatively simple control structures for each individual mode.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a method for the dynamic torque coordination of drive units (4,6) of a hybrid drive (8) of a vehicle, particularly a motor vehicle, wherein the hybrid drive (8) is operated in at least one operating mode, wherein at least one of the drive units (4,6) is operated at an ideal, or approximately ideal operating point at a torque (EtB, Etmin, tDEIS) and/or a rotation that is ideal for said drive unit (4,6) with regard to a selectable operating parameter, and at least one further of the drive units is operated at a balanced torque and/or at a balancing rotation for the dynamic torque and/or rotational balance between the ideal torque (EtB, Etmin, tDEIS) and/or the ideal rotation and a total target torque (tDF) and/or total target rotation required of the hybrid drive (8). The invention provides at least one further operating mode, wherein the other drive unit (4,6) is operated at an ideal, or approximately ideal operating point at a torque (EtB, Etmin, tDEIS) and/or a rotation that is ideal for the other drive unit (4,6) with regard to a selectable operating parameter, and at least one of the drive units (4,6) is operated between the torque (EtB, Etmin, tDEIS) and/or the rotation that is ideal for the further drive unit (4,6) with regard to a selectable operating parameter for the dynamic torque and/or rotational balance, and the total target torque (tDF) and/or the total target rotation required of the hybrid drive (8), and/or at the total target rotation at an additional balancing torque and/or balancing rotation, and/or that a further operating parameter is selected in a further operating mode in order to operate the one or the further drive unit (4, 6) at the ideal, or approximately ideal operating point, wherein a change of the operating modes is brought about during the ongoing operation of the hybrid drive (8). The invention further relates to a corresponding device (2) for the dynamic torque and/or rotational coordination of drive units (4, 6) of a hybrid drive (8) of a vehicle.