Air Core Reactor Sound Mitigation via Phase-Shifted Windings
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Air core reactors produce audible sound due to mechanical forces from alternating current and magnetic fields, which can be a nuisance in populated areas, and existing solutions like sound barriers are costly and obstructive to maintenance.
Innovation Solution
The design of air core reactors is modified to introduce a phase difference in the current flowing through the winding layers, making the forces generated out of phase, thereby reducing the net forces and vibrations that produce sound, while maintaining electrical performance and cost constraints.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If sound barriers are constructed around the reactor, then sound levels are reduced, but maintenance access is obstructed and cost increases
Solution Approach 1:
The patent converts the harmful acoustic vibrations into a beneficial effect by introducing counter-phase currents that generate opposing magnetic forces. These forces actively cancel the vibrations that cause sound, transforming the harmful mechanical vibration into a controlled electromagnetic interaction that reduces noise without physical barriers
Solution Approach 2:
The patent replaces the mechanical sound barrier system with an electromagnetic field-based solution. Instead of using physical structures to block sound waves, the invention uses controlled electromagnetic forces to cancel the vibrations at their source, substituting a mechanical acoustic solution with an electromagnetic field control approach
2Object-affected harmful factors
If sound barriers are constructed around the reactor, then sound levels are reduced, but cost increases
Solution Approach 1:
The patent converts the harmful acoustic vibrations into a beneficial effect by introducing counter-phase currents that generate opposing magnetic forces. These forces actively cancel the vibrations that cause sound, transforming the harmful mechanical vibration into a controlled electromagnetic interaction that reduces noise without physical barriers
Solution Approach 2:
The reactor system provides its own sound mitigation function through the controlled interaction of electromagnetic fields. The system uses its inherent electromagnetic components to generate canceling forces, making the noise reduction capability intrinsic to the reactor operation rather than requiring separate external mitigation systems
3Object-affected harmful factors
If current phase difference is introduced in winding layers, then sound levels are reduced, but electrical performance may be affected
Solution Approach 1:
The patent applies different current phase relationships to different winding layers locally. Specifically, adjacent winding layers are operated with currents that are 180 degrees out of phase, while maintaining proper phase relationships within each layer. This localized phase differentiation cancels vibrations at the source without disrupting the overall electrical performance of the reactor
Solution Approach 2:
The patent changes the phase parameter of the current flowing through adjacent winding layers from the conventional in-phase relationship to a 180-degree out-of-phase relationship. This parameter change fundamentally alters the magnetic force interaction between layers, causing vibration cancellation while maintaining the reactor's electrical function through proper design of the winding connections
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 effectively reduces sound levels emanating from the reactors, eliminating the need for additional sound barriers and allowing for easier maintenance access, by optimizing the acoustic performance without increasing electrical losses or manufacturing costs.
Implementation Method 1
they are subjected to mechanical forces created by the interaction of the electrical current and the magnetic field generated by the reactor
Implementation Method 2
a current in a outermost package is out of phase with a current in another package, the phase relationship between the currents and the magnetic field causing a force to be generated in the outermost package that is out of phase with a force generated in the another package
Data Source
AI summary
An air core reactor (47) including a plurality of concentric conductor winding packages (44, 46) wherein a force (F+) generated by the interaction of current (+) flowing through one package and a magnetic field (42) generated by the reactor is out of phase (Fâ) with a force generated in another package, thereby effectively mitigating audible sound generated by power operation of the reactor. In one embodiment (FIG. 3), the out of phase force may be generated when at least one winding (38c, 37d) of one package (38) is configured to conduct a current (â) that is at least 10 degrees out of phase with a current (+) conducted by another package (40) or other windings (38a, 38b) of the reactor (36).