Active Rotor Segment Phasing for Variable Generator Voltage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Permanent magnet generators in electrical systems, such as those used in aircraft, face challenges with inconsistent voltage generation due to their dependence on rotor speed, leading to increased heat and the need for cooling systems and clutches to manage failures, which add weight and complexity.
Innovation Solution
Incorporating an active rotor segment with second permanent magnets of alternative polarity, along with a fixed rotor segment of first permanent magnets, and an actuator mechanism to displace the active rotor segment relative to the fixed rotor segment, allowing for controlled voltage generation within defined ranges and disabling voltage generation as needed.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If permanent magnet generators are used to generate electrical energy, then high voltage generation in small size is achieved, but voltage consistency deteriorates and heat increase occurs
Solution Approach 1:
The rotor is divided into a fixed rotor segment and an active rotor segment that can be independently controlled. The active rotor segment contains permanent magnets that can be selectively activated or deactivated, allowing independent control of magnetic field contribution. This segmentation enables voltage regulation by adjusting the number of active permanent magnets while maintaining the compact high-power-density structure of permanent magnet generators.
Solution Approach 2:
The active rotor segment is designed to be dynamically adjustable relative to the fixed rotor segment. An actuator mechanism enables real-time reconfiguration of the active rotor segment's position or activation state, allowing the generator to adapt its voltage output dynamically. This dynamic capability maintains voltage consistency across varying operational conditions without requiring additional cooling systems or clutches.
2Power
If rotor speed increases to generate more voltage, then power output is improved, but heat generation increases requiring cooling systems
Solution Approach 1:
Instead of changing rotor speed to control voltage output, the system changes the parameter of permanent magnet activation. By controlling which permanent magnets in the active rotor segment are activated, the generator can adjust voltage output without increasing rotational speed. This parameter change approach decouples voltage control from speed control, preventing excessive heat generation while maintaining adequate power output.
3Reliability
If cooling systems and clutches are added to manage voltage consistency and failures, then system reliability is improved, but device complexity and weight increase
Solution Approach 1:
The active rotor segment serves multiple functions: it enables voltage regulation, provides failure protection, and eliminates the need for separate cooling and clutch systems. By integrating these functions into a single component that can be dynamically reconfigured, the system achieves high reliability without adding the complexity and weight of multiple separate subsystems. The actuator mechanism that controls the active rotor segment also serves as the failure protection mechanism.
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 solution enables more consistent voltage generation without the need for cooling systems or clutches, reducing weight and complexity while maintaining the benefits of permanent magnet generators in terms of size and weight.
Implementation Method 1
Energy flows through the stator to or from the rotor. In an electric motor, the stator provides a rotating magnetic field that drives the rotor. In a generator, the stator converts the rotating magnetic field to electric energy.
Implementation Method 2
the stator provides a rotating magnetic field that drives the rotor. In a generator, the stator converts the rotating magnetic field to electric energy.
Data Source
Figure 1
Figure 2A
Figure 2B
AI summary
An example electrical machine is described that includes active segments for variable voltage generation. The electrical machine includes a drive shaft, a fixed rotor segment, an active rotor segment, and an actuator mechanism. The fixed rotor segment is coupled to the drive shaft, where the fixed rotor segment has affixed thereon first permanent magnets of alternating polarity. The active rotor segment axially is adjacent to the fixed rotor segment along the drive shaft. The active rotor segment also has affixed thereon second permanent magnets of alternating polarity. The actuator mechanism is configured to articulate the active rotor segment relative to the fixed rotor segment and thereby alter a phase of the second permanent magnets relative to the first permanent magnets in order to change a first voltage generated by the electrical machine to a second voltage generated by the electrical machine.