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

  Jul 28, 2025

  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.    

  Hot Tags : Inrush Current Limiter Nanocrystalline core for OBC Magnetic Core for OBC Power Electronics for OBC 1K107B Nanocrystalline Core Nanocrystalline Toroidal Core

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  How to Achieve High Inductance and Low Current in Power Supply Designs

  Jul 25, 2025

  In power supply designs, one of the biggest challenges is achieving high inductance without increasing the current too much, which can cause saturation. When this balance is not optimized, systems may emit unwanted noise or experience poor performance due to high current. This issue is particularly common in industries where efficiency, reliability, and noise reduction are critical. Finding a way to maintain high inductance and prevent excessive current from causing saturation is key to optimizing a power supply system.     A real-world case study demonstrates an effective solution to this problem.   One of our client had a power supply that emitted noticeable noise and had high current levels. Despite attempts to reduce the inductance to avoid saturation, the power supply still faced issues. The solution came when we combined nanocrystalline and amorphous magnetic materials in the core of the power supply. This hybrid core design successfully achieved high inductance, prevented saturation, and reduced noise.   Solving the Problem with a Hybrid Core Design The client approached us with a specific issue: when their power supply was powered on, it produced a loud noise and had an unacceptably high current. The issue arose from their earlier attempt to lower the inductance in the magnetic core to prevent saturation. However, this didn’t solve the problem, as it compromised the system’s overall performance. Their main challenge was to maintain high inductance while preventing the core from saturating, which would increase the current. To solve this issue, we proposed a hybrid approach by using a combination of nanocrystalline and amorphous materials for the magnetic core. The core was designed with the inner two-thirds made from nanocrystalline material and the outer third from amorphous material. This unique material combination solved the problem by offering several key advantages.   Nanocrystalline and Amorphous Materials: A Perfect Combination Both nanocrystalline and amorphous materials have specific magnetic properties that make them ideal for different parts of a power supply’s magnetic core: Nanocrystalline Material:Nanocrystalline materials are known for their high magnetic permeability and excellent performance at high inductance. They provide low core losses, which means more efficient energy storage in the magnetic field. The nanocrystalline material in the inner part of the core helped achieve the desired high inductance without overloading the system. Amorphous Material:Amorphous materials have a low saturation point and are highly stable at high frequencies. By placing amorphous material in the outer part of the core, we prevented the core from reaching saturation. This allowed the power supply to handle higher current levels without causing the core to saturate, keeping the system stable and free from excessive noise. By combining these two materials in the core design, we were able to achieve high inductance without sacrificing efficiency or stability.   Advantages of the Hybrid Core Solution This hybrid approach brought several significant benefits to the power supply system: Higher Efficiency: By combining the high inductance of nanocrystalline material with the low saturation point of amorphous material, we achieved a highly efficient system. The power supply could store more energy while preventing the core from becoming saturated. Reduced Noise: One of the key issues the client faced was the noise emitted by the power supply. The hybrid core design minimized this noise by preventing saturation and reducing vibrations. Improved Stability: With this solution, the power supply could operate under varying load conditions without the risk of instability or saturation. This increased the overall reliability of the system. Cost-Effective: This solution provided a way to solve the problem effectively without resorting to expensive or complex materials. The hybrid core design was both affordable and highly effective.   How This Solution Benefits Power Supply Designers For designers facing similar challenges, the combination of nanocrystalline and amorphous materials offers a straightforward and effective way to balance high inductance and low current. It provides a way to optimize power supply systems for better efficiency, reduced noise, and reliable performance. Additionally, it offers a cost-effective solution to improve the overall design without compromising on quality or performance. This solution is especially beneficial for applications where reducing noise and improving efficiency are critical. It provides a stable and reliable way to manage the inductance and current, ensuring optimal performance in demanding environments.   Final Thoughts on Achieving High Inductance and Low Current By using a combination of nanocrystalline and amorphous materials, we were able to create a highly effective solution that addressed the challenges of achieving high inductance and preventing saturation in a power supply design. The hybrid core not only solved the current and saturation issues but also reduced noise, improved stability, and increased efficiency. This case study shows that with the right approach and material selection, it is possible to achieve optimal performance in power supply systems. If you are facing similar challenges, don’t hesitate to reach out to us for tailored solutions that can help optimize your designs.   Contact Information For more information or to discuss your specific project, feel free to contact us at: Website: www.amorphousoem.com WhatsApp: +86 13686646827 Email: julia@amorphousoem.com   We are ready to help you achieve better performance and reliability in your power supply designs with our advanced magnetic materials.

  Hot Tags : nanocrystalline and amorphous materials for magnetic cores power supply noise reduction and saturation prevention high inductance low saturation magnetic core design benefits of hybrid magnetic core design for power supply cost-effective solutions for power supply optimization wound nanocrystalline core

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  How to Improve Cased Nanocrystalline Core Performance: The Game-Changing Impact of Varnish Curing Before Casing

  Jul 17, 2025

  As a professional OEM/ODM manufacturer and global exporter of nanocrystalline and amorphous magnetic cores, we’ve faced — and solved — one of the most frustrating problems in magnetic component manufacturing: performance degradation of cased nanocrystalline cores after copper winding. Despite our best efforts with process control and material optimization, the issue remained. Until we discovered one simple yet powerful step that changed everything: varnish curing of the core before casing. In this article, we’ll walk you through the core problem, why conventional fixes don’t work, and how pre-casing varnish curing is a proven solution to improve cased nanocrystalline core performance in real-world production.   The Problem: Performance Degradation After Winding in Cased Cores What Happens in Production Cased nanocrystalline cores — usually toroidal or rectangular cores sealed with plastic, epoxy, or metal shells — are widely used in: High-frequency transformers Common mode chokes EMI filters Inverters and power supplies Before being integrated into magnetic components, these cores are typically cased for mechanical strength, electrical insulation, and ease of handling. However, once copper winding is applied to these cased cores, we consistently observed a decline in performance, including: Lower initial permeability Higher core loss Reduced stability under temperature variation Poorer high-frequency behavior These issues directly affect the quality and efficiency of the final device.   Why Traditional Solutions Don’t Work 1. Process Optimization We tried: Adjusting winding tension Controlling ambient humidity and temperature Improving casing procedures Post-winding annealing None of these consistently prevented the performance drop in cased cores after winding. 2. Material Substitution We experimented with: Different casing materials Various adhesives and bonding resins Modified insulation layers Again, results were unstable. The degradation continued.   Root Cause: Internal Stress and Magnetic Structure Disruption Nanocrystalline ribbon is highly sensitive to mechanical stress and surface tension. During the winding process, pressure from the copper wire and friction from the casing interface can disturb the internal magnetic domains of the ribbon. In cased products, this stress is harder to relieve because the core is confined within a rigid structure. Once distorted, the magnetic domains no longer function optimally — permeability drops, core loss increases, and overall stability suffers.   The Real Solution: Varnish Curing Before Casing After multiple tests, we found a breakthrough: spraying insulating varnish on the bare nanocrystalline core and curing it before applying the casing and winding. This varnish — specifically, a solvent-free polymer-based varnish such as V852-3 — forms a thin, flexible, nanograde insulating layer on the surface of the core. Once cured, it acts as a buffer between the magnetic material and mechanical stress.   How Varnish Curing Works Step-by-Step Process Core Surface Cleaning: Dust, oil, and oxidation are removed. Varnish Spraying: The varnish is evenly sprayed over the entire surface. Curing: The core is baked at 80–120°C for 30–60 minutes, depending on size. Casing: The cured core is then inserted into the casing. Winding: Copper coils are applied as usual.   How It Improves Magnetic Performance Reduces Stress Sensitivity: The cured layer absorbs winding pressure and mechanical stress from the casing. Preserves Magnetic Domains: Magnetic alignment remains stable under force and heat. Improves Thermal Cycling Stability: Coating remains intact even after repeated temperature changes. Enhances Surface Uniformity: Coating smooths minor imperfections, improving magnetic consistency.   Real-World Results from Our Factory After adopting varnish curing in our production line, we observed the following: Test Parameter Without Varnish With Pre-Casing Varnish Initial Permeability (μi) Drops 15–25% after winding Stays within ±5% range Core Loss @20kHz, 0.1T Increases by 30% Reduced by 20–30% High-Frequency Stability Inconsistent Stable across samples Production Rejection Rate ~8–10% <2%   We also received positive feedback from export customers in Europe, South Korea, and the US, especially those working in automotive power supplies, photovoltaic inverters, and EV charging systems.   Why Varnish Curing Beats Other Solutions Method Effectiveness Comments Process tuning ★☆☆☆☆ Temporary benefit, not scalable Casing material change ★★☆☆☆ Costly and still stress-sensitive Annealing post-winding ★☆☆☆☆ Risky in cased products Varnish curing before casing ★★★★★ Simple, stable, and proven effective     Application Fields That Benefit Most High-frequency transformers (20kHz–100MHz) Common-mode chokes for EV charging EMI suppression for power electronics Photovoltaic inverters and wind converters UPS systems and power storage devices DC-DC converters in automotive and rail   We Are a Leading Manufacturer and Exporter With over 10 years of experience in nanocrystalline and amorphous magnetic core production, we provide: Customized OEM/ODM services Cased and uncased cores in toroidal, cut, and block shapes High-frequency, high-efficiency materials Mass production with stable quality control Global export logistics and multilingual support We do not manufacture varnish, but we successfully integrate varnish curing into our own core production lines to deliver the best performance for our customers.   ✅ Improve Your Magnetic Core Reliability Today If you're tired of post-winding performance issues in cased cores, consider switching to a better solution. Let us help you: 🧪 Request free samples 🛠 Get custom nanocrystalline core / amorphous core solutions 📦 Start stable OEM/ODM partnerships 🌍 Deliver globally with technical support 📞 Contact Us 🌐 Website: www.amorphousoem.com 📱 WhatsApp: +86 13686646827 📩 Email: julia@amorphousoem.com 🕘 Working Hours: Mon–Sat, 8:00–18:00 (China Time)   💬 Let’s Build a Better Core — From the Inside Out.  

  Hot Tags : How to fix magnetic core performance drop Magnetic core winding stress solution Improve amorphous or nanocrystalline core properties Best practices for transformer core manufacturing OEM nanocrystalline core exporters with advanced curing improve cased nanocrystalline core performance

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