In industrial switch-mode power supply (SMPS) designs, magnetic amplifiers (or saturable reactors) are often used for secondary-side voltage regulation. However, many engineers focus solely on the unit price of the magnetic core while overlooking the efficiency losses, increased thermal management requirements, and larger system footprint caused by improper core selection. These factors represent the true "hidden costs" in power supply design.
The Source of Hidden Costs: Common Misconceptions in Core Selecti
Different magnetic core materials exhibit significant differences in four critical areas:
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Saturation Flux Density (Bs)
Determines the maximum magnetic flux a core can handle and directly affects achievable power density.
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Coercivity (Hc)
Influences the energy consumption of the saturation-reset cycle. Higher coercivity generally results in greater core losses.
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High-Frequency Loss (>100 kHz)
Core losses can vary by several times between different materials at high switching frequencies.
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Temperature Stability
In wide-temperature environments such as automotive and outdoor applications, magnetic property drift can lead to unstable output voltage regulation.
Focusing solely on the purchase price of the core may save a few dollars initially, but can ultimately result in significantly higher costs associated with heat sinks, enclosures, maintenance, and field failures.
Comparison of Key Magnetic Core Materials
| Parameter | Ferrite | Permalloy | Amorphous Core |
|---|---|---|---|
| Saturation Flux Density Bs (T) | ~0.5 | ~0.8 | ~1.56 (Fe-based) |
| Coercivity Hc (A/m) | Relatively High | Moderate | < 18 |
| Curie Temperature (°C) | 120–300 | ~400 | > 560 |
| High-Frequency Loss (>100 kHz) | High | Medium | Low |
| Temperature Stability | Moderate | Good | Excellent |
| Typical Applications | Low-frequency, low-power systems | Medium-precision applications | High-frequency, high-power, wide-temperature, high-efficiency systems |
How Do These Hidden Costs Translate into Real Benefits?
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Reduced Energy Losses
Amorphous cores feature extremely low coercivity (<18 A/m), resulting in substantially lower saturation-reset losses compared with ferrite cores.
In continuous operation, overall power supply efficiency can improve by approximately 1–3 percentage points, potentially saving dozens of kilowatt-hours annually in power supplies rated at several hundred watts.
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Smaller Transformer Size
The higher saturation flux density (Bs) enables designers to use smaller core cross-sectional areas. At the same time, lower losses reduce cooling requirements, allowing for significant reductions in overall system size.
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Wider Operating Temperature Range
With a Curie temperature exceeding 560°C, amorphous cores maintain stable performance across a temperature range of -55°C to +150°C.
This eliminates the need for extensive derating, while simultaneously improving reliability and service life.
Why Choose Shinhom?
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Fully Integrated Manufacturing
From amorphous ribbon production and core cutting to final assembly, Shinhom maintains a complete manufacturing process and operates under IATF 16949-certified quality systems.
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Outstanding Magnetic Performance
- High saturation flux density (Fe-based ≥ 1.56 T)
- Ultra-low coercivity (<18 A/m)
- Wide operating temperature range (-55°C to +150°C)
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Flexible Design Options
Available in toroidal, cut-core, and other configurations, with support for custom dimensions and winding requirements.
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Engineering Support
Based on your converter topology (forward, flyback, resonant, etc.), switching frequency, and current requirements, Shinhom can provide simulation data and core selection recommendations to accelerate product development.
Evaluate Whether Your Design Is Paying Hidden Costs
- Free Samples：Request standard MA Series amorphous cores and evaluate them directly against your current design.
- Technical Comparison Reports：Provide your existing core model, and our engineering team will prepare a comparative loss analysis report.
- Custom Design Support：Submit your power, frequency, and temperature requirements and receive professional core selection recommendations within 24 hours.
📧 ： sales@shinhom.com
🌐 ： www.shinhom.com