Electromagnetic Rotating Machine Torque Weight Contradiction
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Solution Overview
Problem
Conventional turbofan engines require heavy magnetic field systems and large electric generating systems to produce big torque for large-diameter fans, leading to increased weight and energy consumption, and face challenges in maintaining a constant electromagnetic force direction for efficient rotation.
Innovation Solution
An electromagnetic rotating machine design where the armature coil is on the outer circumference and the excitation coil is on the inner surface, eliminating the need for iron cores and using split coils with controlled excitation to generate effective electromagnetic force without external power, allowing for lightweight and high-efficiency operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If a magnetic field system with large capacity and iron-core structure is used to generate big torque, then the torque output is improved, but the weight of the engine section increases
Solution Approach 1:
The patent extracts and eliminates the iron-core structure from the armature, retaining only the armature coil. This removes the heavy magnetic field system while preserving the torque-generating capability through electromagnetic induction, directly resolving the contradiction between torque output and weight.
Solution Approach 2:
The patent replaces the conventional iron-core magnetic field system with a pure electromagnetic induction system. Instead of using mechanical iron cores to concentrate and generate magnetic fields, the system relies on electromagnetic induction from the excitation coil to generate the necessary magnetic field for torque production, substituting a lighter electromagnetic system for a heavier mechanical magnetic system.
2Power
If current is applied to armature coil in magnetic field to generate electromagnetic force, then motive power is produced, but the direction of electromagnetic force must be constantly maintained which requires complex control systems
Solution Approach 1:
The patent employs periodic alternation of the magnetic field direction through the excitation coil, which automatically induces current in the armature coil with the appropriate direction to maintain constant electromagnetic force. This periodic action eliminates the need for complex control systems, as the alternating magnetic field naturally produces the required current direction through electromagnetic induction.
Solution Approach 2:
The system uses the changing magnetic field from the excitation coil to automatically induce current in the armature coil, which then generates the electromagnetic force needed for rotation. The system serves itself by using the excitation field to create the armature current, eliminating the need for external control mechanisms to maintain constant force direction.
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 design achieves significant weight reduction and efficient energy use by producing big torque with small electromagnetic force, enabling the rotation of large-diameter fans with reduced power consumption and improved energy efficiency.
Implementation Method 1
when the magnetic field is changed in time, induced current is applied to the armature coil based on Faraday's law of electromagnetic induction
Implementation Method 2
electromagnetic force with the size and direction that are proportional to the vector product (i×B) between the induced current (i) and the magnetic field (B) is generated by the interaction between induced current (i) and the magnetic field (B)
Data Source
AI summary
In order to obtain an electromagnetic rotating machine of lightweight and high energy efficiency, which produces big torque for rotating a large-diameter fan, a coil A and coil B as excitation coils are disposed on an inner peripheral surface of a fan casing so as to face an outer circumference of the fan, and a coil M as an armature coil crosses at a central portion and is disposed on the outer circumference of the fan. The relationships |Iai|=|Iai+1| and Iai=−Iai+1, or |Ibi|=|Ibi+1| and Ibi=−Ibi+1 are obtained respectively for the coil A or coil B by a current control device (not shown). Moreover, the coil A and coil B are subjected to excitation control such that the direction of effective electromagnetic force, which is generated by an interaction between an effective magnetic field formed by the coil A and effective induced current applied to the coil M by the coil B, corresponds to the direction of rotation of the fan.