Hybrid Motor Torque Path Switching Between ISG and EFAD
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing hybrid electric vehicles with single-motor systems lack the ability to switch between the ISG path and the EFAD path, limiting their operational efficiency and flexibility in achieving multiple driving modes.
Innovation Solution
A control method that acquires specific vehicle and battery states to transition the torque output path of the motor between the ISG and EFAD paths based on preset conditions, including vehicle speed, brake and accelerator pedal openings, and battery charge levels, ensuring smooth switching and efficient energy management.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the hybrid power system uses a complex structure to achieve multiple operating modes, then the adaptability is improved, but the device complexity increases and space utilization decreases
Solution Approach 1:
The motor is designed to perform multiple functions by switching between ISG path (integrated starter generator) and EFAD path (electric front axle drive). The same motor can provide starting assistance, driving assistance, and energy recovery across different operating modes without requiring separate dedicated components for each function, thereby achieving multiple operating modes while controlling system complexity
Solution Approach 2:
The system dynamically switches the motor's torque output path between ISG and EFAD configurations based on real-time operating conditions such as vehicle speed, accelerator pedal opening, and battery state of charge. This dynamic reconfiguration allows the system to adapt to different driving scenarios without permanent structural changes, maintaining versatility while simplifying the overall system architecture
2Adaptability or versatility
If the hybrid power system occupies a relatively large space to accommodate complex components, then the adaptability is improved, but the space utilization decreases
Solution Approach 1:
By making the motor multi-functional through path switching between ISG and EFAD configurations, the system eliminates the need for separate dedicated motors or components for different operating modes. This consolidation reduces the overall space required while maintaining the capability to operate in multiple modes including pure electric, hybrid series, hybrid parallel, and energy recovery modes
3Device complexity
If the motor remains on a single torque output path, then the device complexity is reduced, but the adaptability decreases
Solution Approach 1:
The control system dynamically determines the appropriate torque output path (ISG or EFAD) based on real-time vehicle operating conditions including vehicle speed, accelerator pedal opening, brake pedal opening, and battery state of charge. The system switches paths optimally: using ISG path at low speeds for starting and low-speed assistance, and EFAD path at higher speeds for driving assistance and energy recovery, thereby achieving adaptability without excessive complexity
Solution Approach 2:
The control system proactively manages the motor's torque output path selection based on predicted driving conditions and battery state of charge levels. By anticipating when path switching will be beneficial (such as switching to EFAD when battery charge is low and vehicle speed exceeds threshold), the system prepares and executes transitions in advance, improving responsiveness while maintaining manageable system complexity
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
In order to solve a technical problem that switching between an ISG path and an EFAD path cannot be performed, the present invention provides a control method for switching a torque output path of a motor of a hybrid electric vehicle, which includes: acquiring an initial path state of a torque output path of a motor; acquiring an initial vehicle speed of the vehicle; acquiring a brake pedal opening; acquiring an initial accelerator pedal opening; acquiring an initial state of charge of a vehicle battery; if the initial path state is the ISG path, the initial state of charge is less than a first preset value, the initial vehicle speed is less than a second preset value and the initial accelerator pedal opening is greater than a third preset value, controlling the torque output path of the motor to be transitioned from the ISG path to the EFAD path; if the initial path state is the EFAD path, the initial state of charge is less than the first preset value, the brake pedal opening is greater than a fourth preset value and the initial vehicle speed is greater than a fifth preset value, controlling the torque output path of the motor to be transitioned from the EFAD path to the ISG path. The invention improves the drivability, comfort and safety of the vehicle.