Propulsion Assembly Torque and RPM Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current electric motor systems face challenges in maintaining rotor blade RPM while varying collective pitch for rapid thrust control, leading to lag and reduced responsiveness due to the need for complex torque mapping and feedback mechanisms.
Innovation Solution
The implementation of a thrust and RPM controller that uses anticipatory feed-forward signals and PID control to manage motor torque and blade pitch, allowing for immediate thrust adjustments by varying collective blade pitch and maintaining RPM through a lead/lag filter and torque-to-pitch lead modules.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If complex torque mapping and feedback mechanisms are used to maintain rotor blade RPM while varying collective pitch, then RPM stability is improved, but system complexity and response time increase
Solution Approach 1:
The patent applies anticipatory feed-forward control by pre-calculating and applying torque adjustments based on expected pitch changes before they occur. The controller receives a pitch command and immediately generates the corresponding torque command in advance, eliminating the need for complex real-time feedback loops to maintain RPM stability during pitch variations.
Solution Approach 2:
The patent implements feedback control through a closed-loop system that continuously monitors actual RPM and compares it with the target RPM. The controller adjusts torque commands based on the RPM error signal, using proportional, integral, and derivative actions to maintain stable RPM while allowing rapid pitch changes, thereby resolving the contradiction between stability and responsiveness.
2Stability of the object's composition
If complex torque mapping and feedback mechanisms are used to maintain rotor blade RPM while varying collective pitch, then RPM stability is improved, but responsiveness and system bandwidth decrease
Solution Approach 1:
The patent applies anticipatory feed-forward control by pre-calculating and applying torque adjustments based on expected pitch changes before they occur. The controller receives a pitch command and immediately generates the corresponding torque command in advance, eliminating the need for complex real-time feedback loops to maintain RPM stability during pitch variations.
Solution Approach 2:
The patent replaces complex mechanical feedback mechanisms with electronic control algorithms that process pitch commands and generate appropriate torque commands through computational models. This substitution enables faster response times by using mathematical calculations rather than mechanical sensing and actuation loops.
3Speed
If immediate thrust adjustments are made by varying collective blade pitch, then responsiveness is improved, but RPM stability deteriorates
Solution Approach 1:
The patent implements feedback control through a closed-loop system that continuously monitors actual RPM and compares it with the target RPM. The controller adjusts torque commands based on the RPM error signal, using proportional, integral, and derivative actions to maintain stable RPM while allowing rapid pitch changes, thereby resolving the contradiction between stability and responsiveness.
Solution Approach 2:
The patent replaces complex mechanical feedback mechanisms with electronic control algorithms that process pitch commands and generate appropriate torque commands through computational models. This substitution enables faster response times by using mathematical calculations rather than mechanical sensing and actuation loops.
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 enhances system bandwidth and responsiveness by allowing immediate thrust adjustments and maintaining RPM stability, reducing lag and improving control precision in aircraft operations.
Implementation Method 1
Most electric motors operate through the interaction between the motor's magnetic field and an electric current in a wire winding to generate force in the form of torque applied on the motor's shaft
Data Source
AI summary
A system can include a flight controller for an aircraft that includes an electric motor that drives blades with a variable pitch, where the flight controller receives a command to change a flight characteristic of the aircraft and creates a torque command and a revolutions per minute (RPM) command. The system can also include a propulsion assembly, where the propulsion assembly creates a current command based at least in part on the torque command and the RPM command, creates a blade pitch command based at least in part on the torque command and the RPM command, communicates the current command to the electric motor to change a mechanical output of the electric motor, and communicates the blade pitch command to blade actuators to control the pitch of the blades. The current command and the blade pitch command cause the blades of the aircraft to rotate at a predetermined RPM.