Torque Response Control for Electric Vehicle Motors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electric vehicles with electric motors face challenges in providing drivers with a sense of acceleration that matches their desired acceleration due to mismatched output torque characteristics, leading to dissatisfaction and difficulty in delicate driving manipulation, as traditional transmission solutions increase friction loss and reduce mileage.
Innovation Solution
A torque response control apparatus for electric motors that adjusts torque response based on vehicle speed and accelerator position, using a torque response determining coefficient to set target motor torque and control the inverter to achieve desired acceleration, thereby compensating for differences between required and actual acceleration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a transmission is arranged at the output side of the electric motor to adjust torque, then the driver can obtain desired acceleration, but friction loss increases and travel distance becomes shorter
Solution Approach 1:
The patent replaces the mechanical transmission system with an electrical control system. The inverter controls the motor torque response by adjusting current supply to the motor, eliminating the need for mechanical transmission components that cause friction loss. This substitution achieves the desired acceleration response through electrical control rather than mechanical adjustment.
Solution Approach 2:
The patent changes the torque response parameter of the motor by controlling the inverter's current supply. The control unit adjusts the torque response determining coefficient based on vehicle speed and accelerator position, dynamically changing the motor's torque characteristics to match desired acceleration without mechanical transmission.
2Speed
If the torque response of the electric motor is increased to improve acceleration response, then the sense of acceleration improves, but delicate driving manipulation becomes difficult due to excessive torque
Solution Approach 1:
The patent makes the torque response determining coefficient dynamic rather than fixed. The control unit adjusts this coefficient in real-time based on vehicle speed and accelerator position, allowing the system to provide high torque response when needed for acceleration while reducing torque response for delicate manipulation, thus adapting to different driving conditions.
Solution Approach 2:
The patent changes the torque response parameter dynamically by adjusting the torque response determining coefficient. When vehicle speed is low and accelerator position indicates gentle input, the coefficient is reduced to enable delicate manipulation. When vehicle speed is high or rapid acceleration is needed, the coefficient is increased to provide responsive acceleration.
3Speed
If the torque response determining coefficient is made large to increase torque response, then acceleration response improves, but torsional vibration is generated in the motor driving system
Solution Approach 1:
The patent dynamically adjusts the torque response determining coefficient based on operating conditions. By making the coefficient variable rather than fixed, the system can select optimal values that provide adequate torque response while avoiding conditions that generate excessive torsional vibration in the motor driving system.
Solution Approach 2:
The patent optimizes the torque response determining coefficient by changing its value according to vehicle speed and accelerator position. This parameter optimization allows the system to achieve sufficient torque response for desired acceleration while selecting coefficient values that minimize torsional vibration generation in the motor driving system.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution allows drivers to experience a sense of acceleration that closely matches their desired acceleration, reducing dissatisfaction and enabling more precise driving control without the drawbacks of traditional transmission systems, such as increased friction loss and reduced mileage.
Implementation Method 1
controls an inverter 6 in such a manner that the electric motor 2 is fed with a current to realize the target motor torque
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
When a vehicle speed VSP is low, a torque response determining coefficient K is made small to lower a motor torque response, and as the vehicle speed VSP increases, the torque response determining coefficient K is increased to increase the motor torque response. With this, a delicate driving manipulation for a delicate driving power control required in a lower speed running is easily achieved, and a torque increase is rapidly made in a higher speed running, so that a sense of acceleration required in such higher speed running is fulfilled. In a lower load condition where an accelerator position APO is low, the torque response determining coefficient K is made small to lower the motor torque response, and as the load increases, the torque response determining coefficient K is increased to increase the motor torque response. With this, a delicate driving manipulation for a delicate driving power control required in a lower load running is easily achieved, and a torque increase is rapidly made in a higher load running, so that a sense of acceleration required in such higher load running is fulfilled.