Wire-wound inductor WL40025

ferriteferrous corehigh-current

Product overview
A toroid power inductor is a passive magnetic component in a toroidal shape, used in power electronics to store and transfer energy, control current flow and filter voltage variations. The toroidal geometry provides a closed magnetic path that reduces flux leakage, lowers electromagnetic interference (EMI) and increases magnetic efficiency compared with open-core designs. WL40025 series can be manufactured with ferrite, powdered iron, sendust or metal alloy cores according to application requirements.

How it works
Current through the winding generates a magnetic field in the toroidal core. When current varies, the field stores and releases energy, smoothing current ripple and filtering switching noise in power supplies and converters. The closed magnetic circuit of the toroid minimizes stray flux and improves efficiency in high-frequency switching environments.

Applications

• Switching power supplies and DC–DC converters
• Industrial automation and motor drive systems
• Renewable energy inverters (solar, wind converters)
• Electric vehicle power modules (BMS, onboard chargers)
• Telecommunications power and filtering modules
• Audio electronics, UPS systems and selected medical equipment
• EMI suppression and power line filtering in advanced electronics

Advantages

• High magnetic efficiency due to closed magnetic path (low flux leakage)
• Reduced EMI emission compared with open-core inductors
• Compact form factor enabling high inductance per volume
• High current handling with low copper and core losses
• Core and winding options customizable to frequency and power requirements

Disadvantages

• Winding process can be more complex and costly than for some other inductor types
• Component mounting and PCB integration may require specific mechanical solutions
• Cooling options are limited for very high-power designs
• Incorrect core material selection can reduce performance at certain frequencies

Technical datasheet (typical values)

• Core material: Sendust (Fe‑Si‑Al) (other materials available)
• Inductance range: 10 µH – 100 mH (typical)
• Rated current: 3 A – 10 A (typical)
• Saturation current: up to 15 A (typical)
• Operating frequency: 10 kHz – 100 kHz (typical)
• Operating temperature: -40°C to +125°C
• Insulation: enameled copper wire
• Core shape: toroidal

Customization
Toroid power inductors can be custom designed (core size, number of turns, wire gauge, target inductance, current rating, insulation and mounting style) to meet specific electrical and mechanical requirements for industrial applications.

Troubleshooting & reliability
Common failure modes include overheating (from excessive current or insufficient cooling), inductance variation (wrong core choice, winding defects or aging), magnetic saturation (exceeding saturation current), EMI issues (layout or wiring faults) and physical damage (insulation or winding degradation). Regular electrical testing, thermal monitoring and correct component specification reduce the risk of failure.

Technical specifications

• Model name: WL40025
• Core materials supported: ferrite, powdered iron, sendust, metal alloys
• Inductance range available: 10 µH – 100 mH (typical)
• Rated current range: 3 A – 10 A (typical)
• Saturation current: up to 15 A (typical)
• Operating frequency: 10 kHz – 100 kHz (typical)
• Operating temperature range: -40°C to +125°C
• Insulation: enameled copper wire
• Typical uses: power supplies, converters, renewable energy, EV systems, industrial automation, EMI suppression