Nanocrystalline Cores for High Power Inverters
Intro
During analysis of modern hybrid inverter I found that power transformer of bidirectional isolated DC-DC converter made using unusual toroid cores, the main thing is that it has very high magnetic permeability.
Aliexpress
 | 3PCS/SET T644020 High Inductance Nanocrystalline Transformer Core |
 | 2PCS/SET T50x42x25 High Inductance Nanocrystalline Core |
Existing Sizes
| Aliexpress | Alibaba |
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Teardown (Disassembling)
Structure
The core made from thin foil:
Deformation
Looks like solid but actually able to deformation (parameters changes under deformation):
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Flame
Measurement
I tested several units from one package from the same seller:
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Analysis
| Average | 186.25uH |
| Median | 185.55uH |
| Min | 150uH |
| Max | 230.2uH |
Deviation
| A_L (µH) | A_L (µH) | Deviation |
| CORE1 | 172.5uH | -7.4% |
| CORE2 | 150uH | -19.5% |
| CORE3 | 230.2uH | +23.6% |
| CORE4 | 204.4uH | +9.8% |
| CORE5 | 198.7uH | +6.6% |
| CORE6 | 161.8uH | -13.1% |
More Photos
Tip: use saw tool to cut plastic.
Core made from thin foil of amorphous nanocrystalline metal fusion.
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Conclusions
| 🟢 | Modern inverters use nanocrystalline core for transformer |
| 🟡 | Magnetic permeability is depends on and could be 25% |
| 🟡 | Deformation cause parameters changes |
| 🔴 | Disassembling will cause damage of core |