How One EV Charging Innovator Solved Their Inrush Current Challenge with a Nanocrystalline Core？

In the rapidly evolving world of electric vehicles (EVs), power density and efficiency are everything. As manufacturers strive to build smaller, smarter, and more efficient onboard chargers (OBCs), even minor components—like magnetic cores—can make a major difference.

This was exactly the case for a North American EV power electronics company designing their next-gen OBC platform.

The Challenge: Inrush Current Suppression in Compact Spaces

Their engineering team was facing a familiar yet critical issue: how to manage inrush current during power-up without compromising on board space or thermal reliability.

Standard ferrite-based cores simply couldn’t meet the demands:

• Too much core loss at high frequencies

• Thermal instability beyond 100°C

• Inconsistent inductance affecting EMI compliance

They needed a new solution—one that was compact, thermally robust, and capable of delivering high inductance in a tight form factor.

The Solution: 1K107B Nanocrystalline Core

That’s when they turned to Dongguan JH Amorphous for help.

Our recommendation: the 1K107B Nanocrystalline Toroidal Core, designed specifically for current limiting and EMI suppression in demanding power environments.

Key Specifications:

• Material: Nanocrystalline alloy

• Size: 12.0 × 8.35 × 12.0 mm

• Initial Permeability (μi): >80,000

• Saturation Flux Density: ~1.2 T

• Operating Temperature: –40°C to +140°C

• Coating: Blue epoxy insulation

This unique combination of properties allows the core to:

• Deliver stable inductance over a wide frequency range (10 kHz – 1 MHz)

• Suppress inrush current without magnetic saturation

• Perform reliably in high-heat EV environments

The Results: Smaller Footprint, Better Thermal Margin

After lab testing, the client was impressed. The 1K107B core not only met their technical targets—it exceeded them.

✅ 20% reduction in PCB space usage
✅ Improved EMI filter stability
✅ Reliable operation at elevated temperatures
✅ Higher efficiency in inrush current suppression

They have since moved the design into full production, and the 1K107B is now integrated into thousands of OBCs hitting the EV market.

Why Nanocrystalline Cores Are the Future of Power Electronics

As EVs and renewable power systems demand higher efficiency and thermal resilience, nanocrystalline materials are proving to be a superior alternative to traditional ferrites in many applications:

• Inrush Current Limiters

• EMI Filters

• DC/DC and AC/DC converters

• Renewable energy inverters

Looking for a Better Magnetic Core?

At Dongguan JH Amorphous, we specialize in custom and standard magnetic core solutions for high-performance applications. Whether you’re designing for EVs, power grids, or automation systems, we can help.

📩 Contact us for samples, datasheets, or to discuss your design goals.