Induction Motor Resonance Control for Lower Supply Voltage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Induction machines, particularly air-cored motors and generators, require high supply voltages, which is a drawback as it increases weight, cost, and reduces efficiency, making them less competitive in applications like electric vehicles where power-to-weight ratio is crucial.
Innovation Solution
A method using a modified indirect field-oriented control algorithm that sets stator speed based on actual rotor speed to achieve electrical resonance, reducing the required voltage by operating at resonance, thereby reducing the need for high supply voltages and enhancing machine performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Weight of moving object
If air-cored induction machines are used to reduce weight and eliminate iron losses, then power-to-weight ratio and efficiency are improved, but supply voltage requirements increase significantly
Solution Approach 1:
The patent applies parameter changes by modifying the control algorithm to operate the air-cored induction machine at electrical resonance conditions. This changes the operating parameters (voltage, current, frequency relationships) to achieve a state where the machine can deliver required power at significantly reduced voltage levels compared to conventional operation, thus resolving the contradiction between weight reduction and voltage requirement increase
2Ease of operation
If conventional indirect field-oriented control is used for air-cored machines, then basic speed control is achieved, but high supply voltages are still required
Solution Approach 1:
The patent enhances the conventional indirect field-oriented control by incorporating feedback mechanisms that continuously monitor operating conditions and adjust control parameters to maintain electrical resonance. This feedback-based control strategy enables the system to automatically operate at optimal resonance points, achieving both ease of operation and reduced voltage requirements simultaneously
3Use of energy by moving object
If electrical resonance operation is implemented, then supply voltage requirements are reduced, but control algorithm complexity increases
Solution Approach 1:
The patent implements a dynamic control approach where the modified indirect field-oriented control algorithm continuously adapts control parameters based on real-time operating conditions to maintain electrical resonance. This dynamic adaptation allows the system to achieve reduced voltage requirements while managing control complexity through systematic algorithm modification rather than complex hardware additions
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
This approach allows for the design of lighter, cheaper machines with reduced voltage requirements, improving efficiency and competitiveness in high-voltage applications by decreasing the supply voltage from 800 V to 600 V, while maintaining efficiency and performance.
Implementation Method 1
setting a stator speed ωs based on the actual rotor speed ωr, so as to stand the machine in an electrical resonance
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
A method for controlling an induction-based motor (IM) or an air-cored resonant-induction motor (ACRIM), comprising the steps of: - receiving a current rotor speed (ωr) from a sensor, - selecting a stator speed (ωs) based on the current rotor speed (ωr), so as to realize a policy of motor control, - using an indirect field-oriented control (IRFOC) adapted algorithm with the stator speed (ωs).