EV Torque Control With Virtual Engine Stall Simulation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electric vehicles lack the driving sensation of an engine stall, which is a key experience for drivers accustomed to manual transmission vehicles, as they cannot replicate the engine stalling mechanism due to the absence of an internal combustion engine.
Innovation Solution
An electric vehicle equipped with an accelerator pedal, pseudo-clutch pedal, pseudo-shifter, and a controller that simulates the torque characteristics of a manual transmission vehicle, allowing the driver to experience engine stalling by adjusting the motor torque output based on driver inputs and external sensor data to ensure safety and smooth traffic flow.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If torque fluctuation control is performed to simulate shifting operation in EVs, then the discomfort for drivers accustomed to MT vehicles is suppressed, but the driver cannot experience the authentic engine stalling sensation
Solution Approach 1:
The patent creates a virtual engine model that copies the torque characteristics and stalling behavior of a real internal combustion engine. The controller simulates engine torque based on accelerator pedal operation, virtual gear stage, and virtual engine speed, and deliberately allows the virtual engine speed to drop to zero to reproduce the authentic stalling sensation that drivers experience in MT vehicles.
Solution Approach 2:
The patent replaces the actual mechanical engine system with a computational model. Instead of using a real internal combustion engine with physical stalling mechanics, the system uses software-based torque fluctuation control that calculates and applies torque variations to mimic engine behavior, substituting physical mechanics with computational simulation.
2Adaptability or versatility
If pseudo-shifter and pseudo-clutch pedal are added to EVs, then drivers can operate the vehicle like MT vehicles, but the driving feeling of actual engine stall cannot be experienced
Solution Approach 1:
The controller serves multiple functions: it controls the electric motor torque, simulates engine torque characteristics, manages virtual gear stage transitions, and reproduces engine stalling behavior. The pseudo-shifter and pseudo-clutch pedal interface with this multi-functional controller, allowing a single system to handle both normal operation and stalling simulation.
Solution Approach 2:
The system creates a virtual replica of the engine-stalling phenomenon through software. The virtual engine model copies the essential characteristics of real engine torque curves and stalling behavior, allowing drivers to experience authentic MT vehicle sensations without an actual internal combustion engine.
3Reliability
If the virtual engine speed is reduced to zero to simulate stalling, then authentic stalling sensation is achieved, but safety issues may arise in critical driving situations
Solution Approach 1:
The controller continuously monitors driving conditions, vehicle speed, and accelerator pedal position to determine whether to allow virtual engine stalling. The system uses feedback from these parameters to decide when stalling simulation is appropriate and when it should be prevented, ensuring safety while maintaining authenticity in suitable situations.
Solution Approach 2:
The system preemptively prevents virtual engine stalling when critical driving situations are detected. By monitoring driving conditions in advance and applying counter-actions (preventing torque reduction) before unsafe stalling can occur, the system eliminates safety risks before they materialize while preserving the stalling sensation in safe conditions.
Data Source
AI summary
The controller of the electric vehicle is configured to control the torque of the electric motor using the MT vehicle model based on the operation amount of the accelerator pedal, the operation amount of the pseudo-clutch pedal, and the shift position of the pseudo-shifter. Further, the controller is configured to execute the stall production process for changing the engine output torque used for calculation of the driving wheel torque to zero when the calculated virtual engine speed using the MT vehicle model becomes lower than the prescribed stall engine speed.