Variable-Magnetic-Force Motor Torque Control for Movable Bodies
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Electric motors used in movable bodies, such as hybrid vehicles, face challenges in providing a wide range of output without increasing the size and weight of components, leading to discomfort for occupants due to transient increases in motor torque when magnetic force is enhanced.
Innovation Solution
A control system that includes an electric drive motor with a variable-magnetic-force magnet and a stator with coils, along with a controller that manages magnetization current to adjust magnetic force, and powertrain components like clutches and brakes to mitigate the increase in motor torque, thereby reducing discomfort for occupants.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If the magnetic force of the magnet is increased to improve motor output, then the motor torque increases, but this causes discomfort to occupants due to transient torque transmission
Solution Approach 1:
The controller preemptively reduces the engaging force of the clutch before the magnetization control increases motor torque, and preemptively increases brake force. This preliminary action prevents the transient torque from being transmitted to the wheels, thereby avoiding occupant discomfort while still allowing the magnetization control to improve motor output.
Solution Approach 2:
The clutch and brake act as intermediary components between the motor and wheels. By controlling the clutch engaging force and brake force, the system mediates the transmission of motor torque to the wheels, filtering out harmful transient torque while allowing useful torque transmission for vehicle propulsion.
2Adaptability or versatility
If the size of the electric motor is increased to achieve wide-range output, then the motor characteristics improve, but the size and weight of equipped components increase
Solution Approach 1:
The system uses a variable-magnetic-force magnet that can dynamically adjust its magnetic force according to load conditions. This dynamic adjustment allows a single motor to deliver high output when needed while maintaining compact size during normal operation, achieving wide-range output capability without permanently increasing component size and weight.
Solution Approach 2:
The magnetization control changes the magnetic force parameter of the magnet based on operational requirements. By adjusting the magnetic force rather than physically changing the motor size, the system achieves adaptable output characteristics across a wide range while keeping the physical dimensions and weight of the motor components constant.
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 system effectively suppresses the transmission of increased motor torque to the vehicle's wheels, minimizing discomfort for occupants during magnetization control by adjusting powertrain components and torque currents, ensuring a smoother ride.
Implementation Method 1
a magnetization controlling module to control magnetizing current flowing through the coils so as to change a magnetic force of the variable-magnetic-force magnet
Implementation Method 2
an electric drive motor including a rotor configured to output a rotational force and provided with a variable-magnetic-force magnet, and a stator opposing the rotor with a gap therebetween and provided with a plurality of coils
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A control system for a movable body configured to move by utilizing a motor torque generated by a drive motor, is provided. The system includes the drive motor including a rotor configured to output a rotational force and provided with a variable-magnetic-force magnet, and a stator opposing the rotor with a gap therebetween and provided with a plurality of coils. The device includes a powertrain component provided so as to be associated with the drive motor, and a controller having a magnetization controlling module configured to control magnetizing current flowing through the coils so as to change a magnetic force of the magnet. During a magnetization control in which the magnetic force of the magnet is increased by the magnetization controlling module, the controller operates the powertrain component to suppress an increase in a moving force applied to the movable body due to an increase in the motor torque.