Aircraft Motor Phase Short-Circuiting for Electromotive Force Protection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Aircraft electric motors driving wheels on the ground face damage from high electromotive forces generated during take-off and landing, which existing mechanical disengagement devices fail to mitigate effectively without increasing aircraft mass significantly.
Innovation Solution
Short-circuiting the electric motor phases during deactivation periods using electrical or electromechanical switches to prevent electromotive force formation, reducing the need for heavy mechanical clutch devices and minimizing mass increase.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a mechanical disengagement device is used to disconnect the electric motor from the wheel during high-speed phases, then the electric motor is protected against electromotive force damage, but the device becomes relatively heavy and complex
Solution Approach 1:
The patent replaces the traditional mechanical disengagement device with an electrical switching system. The control unit activates switching elements (transistors or IGBTs) within the inverter to short-circuit the motor phases electrically, eliminating the need for mechanical clutches or disconnect mechanisms. This substitution reduces mechanical complexity while maintaining protection effectiveness.
Solution Approach 2:
The inverter, which already exists for motor control during operation, is made multi-functional by using its switching elements to perform both motor control and phase short-circuiting during high-speed phases. This eliminates the need for a separate dedicated disengagement device, reducing overall system complexity and component count.
2Reliability
If a mechanical disengagement device is used to disconnect the electric motor from the wheel during high-speed phases, then the electric motor is protected against electromotive force damage, but the aircraft mass increases significantly
Solution Approach 1:
The patent replaces the traditional mechanical disengagement device with an electrical switching system. The control unit activates switching elements (transistors or IGBTs) within the inverter to short-circuit the motor phases electrically, eliminating the need for mechanical clutches or disconnect mechanisms. This substitution reduces mechanical complexity while maintaining protection effectiveness.
Solution Approach 2:
The inverter, which already exists for motor control during operation, is made multi-functional by using its switching elements to perform both motor control and phase short-circuiting during high-speed phases. This eliminates the need for a separate dedicated disengagement device, reducing overall system complexity and component count.
3Weight of moving object
If electrical switches are used to short-circuit the motor phases, then the aircraft mass increases less compared to mechanical devices, but the system requires additional control management
Solution Approach 1:
The inverter, which already exists for motor control during operation, is made multi-functional by using its switching elements to perform both motor control and phase short-circuiting during high-speed phases. This eliminates the need for a separate dedicated disengagement device, reducing overall system complexity and component count.
Solution Approach 2:
The control unit receives information about the aircraft's operational phase (taxiing, takeoff, landing) and automatically activates or deactivates the phase short-circuiting function accordingly. This feedback-based control ensures the protection is applied only when necessary, optimizing both weight savings and control management.
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
Effectively protects the electric motor from damage by preventing electromotive force generation during high-speed ground operations while maintaining a lower aircraft mass compared to traditional mechanical solutions.
Implementation Method 1
the electric motor's rotor is driven by the wheel's rotation, generating a certain electromotive force between the motor's phases
Implementation Method 2
a switching device designed to short-circuit the motor phases
Data Source
Figure 1
Figure 2~4
Figure 5~6
AI summary
The invention relates to a method of managing an electric motor (6) intended to drive a wheel (4) of an aircraft (1) in rotation, the method comprising the step of short-circuiting phases of the electric motor (6) when the aircraft (1) is in a period of engine (6) deactivation during which it is anticipated not to use the electric motor (6).