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Theoretical Analysis of a Magnetic Shielding System Combining Active and Passive Modes
Qingzhi Meng1,2, Zelin Wang1, Qijing Lin1,2,3,4,5
1State Key Laboratory for Manufacturing Systems Engineering, Xi'an Jiaotong University, Xi'an 710049, China.
Nanomaterials (Basel, Switzerland)
|March 27, 2024
Summary
This study presents a novel electromagnetic shielding system combining active and passive modes to effectively block both geomagnetic fields and 50 Hz power-line interference. The proposed system achieves a high shielding efficiency of 113.98 dB, offering excellent protection in complex electromagnetic environments.
Area of Science:
- Physics
- Electrical Engineering
- Materials Science
Background:
- Complex working conditions in power grids necessitate robust magnetic shielding.
- Geomagnetic fields and 50 Hz power-line frequencies pose significant electromagnetic interference (EMI) challenges.
Purpose of the Study:
- To propose and analyze an electromagnetic shielding system combining active and passive modes.
- To evaluate the magnetic shielding efficiency against AC and DC interference.
- To provide theoretical guidance for constructing magnetic shielding systems in EMI environments.
Main Methods:
- A three-dimensional Helmholtz coil with a nested magnetic shielding barrel was designed using COMSOL simulation.
- The magnetic shielding efficiency of different materials (permalloy, pure iron, nickel) was compared.
- The impact of multiple layers on shielding efficiency was investigated.
Main Results:
- Permalloy alloy demonstrated superior shielding performance compared to pure iron and nickel.
- Shielding efficiency increased linearly with the number of shielding layers.
- The combined active and passive system achieved a shielding efficiency of S = 113.98 dB.
Conclusions:
- The proposed hybrid active-passive electromagnetic shielding system is highly effective against AC and DC magnetic fields.
- Permalloy is a preferred material for passive shielding components.
- Layered shielding designs enhance overall efficiency, providing a viable solution for complex EMI environments.
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