Variable-Magnetic-Force Motor Control for Movable Body Torque Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Movable bodies using motor torque face discomfort issues due to temporary decreases in motor torque when magnetic force is reduced, as existing solutions either increase size and weight or fail to effectively manage torque changes.
Innovation Solution
A control system with a drive motor featuring a variable-magnetic-force magnet and a controller that adjusts magnetizing current and powertrain components to minimize discomfort by reducing the impact of magnetic force decreases on motor torque, including clutch engagement force adjustments and torque current management.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the magnetic force of the magnet is reduced to increase power factor, then the power factor of the motor increases, but the motor torque temporarily decreases causing discomfort to the person aboard
Solution Approach 1:
The clutch engaging force is reduced in advance before the magnetic force reduction occurs. This preliminary action prepares the powertrain system to absorb the upcoming torque decrease, preventing it from being transmitted to the wheels and thus avoiding discomfort to the person aboard while allowing the magnet's magnetic force to be reduced for improved power factor
Solution Approach 2:
The clutch serves as an intermediary element between the motor and the wheels. By adjusting the clutch engaging force, it mediates the transmission of torque changes, allowing the magnetic force reduction to occur without directly transmitting the torque decrease to the wheels, thereby resolving the contradiction between improving power factor and preventing discomfort
2Productivity
If the magnetic force of the magnet is reduced to increase power factor, then the power factor of the motor increases, but the moving force applied to the movable body decreases
Solution Approach 1:
The clutch engaging force is reduced in advance before the magnetic force reduction occurs. This preliminary action prepares the powertrain system to absorb the upcoming torque decrease, preventing it from being transmitted to the wheels and thus maintaining the moving force applied to the movable body while allowing the magnet's magnetic force to be reduced for improved power factor
3Object-affected harmful factors
If the clutch engaging force is reduced to suppress discomfort, then the discomfort to person aboard is suppressed, but the transmission of motor torque to wheels is affected
Solution Approach 1:
The clutch engaging force is temporarily reduced only during the specific period when magnetic force reduction occurs, rather than being permanently reduced. This periodic adjustment allows the system to maintain normal torque transmission efficiency during normal operation while suppressing discomfort only when needed during magnet demagnetization control
Solution Approach 2:
The clutch engaging force is reduced in advance before the magnetic force reduction occurs, and then restored after. This temporary, targeted adjustment minimizes the impact on overall transmission efficiency while effectively suppressing discomfort during the critical demagnetization period
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 discomfort in movable bodies by maintaining moving force stability during magnetic force reduction, ensuring a smoother experience by managing motor torque changes through strategic powertrain adjustments.
Implementation Method 1
a stator opposing the rotor with a gap therebetween and provided with a plurality of coils... control magnetizing current flowing through the coils so as to change a magnetic force of the variable-magnetic-force magnet
Implementation Method 2
a drive motor including a rotor configured to output a rotational force and provided with a variable-magnetic-force magnet... moves by utilizing a motor torque generated by a motor
Data Source
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, 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 variable-magnetic-force magnet. During a demagnetization control in which the magnetic force of the variable-magnetic-force magnet is reduced by the magnetization controlling module, the controller operates the powertrain component to suppress a decrease in a moving force applied to the movable body due to a decrease in the motor torque.