One Machine Solves PFC, Butterfly and Common Mode Winding for EV Inductor Manufacturer

Toroidal Winding Machine Case Study | PFC, Butterfly & Common Mode Solution

This case study shows how a fully automatic toroidal winding machine helped an EV inductor factory solve three winding processes with one device, cutting costs and improving consistency.

1. Client Background

The client is a professional electronic component manufacturer located in East China, focusing on the production of EV charging inductors, power supply common-mode chokes, and PFC inductors. The company serves new energy vehicle and industrial power supply customers, with daily toroidal coil production demand of over 8,000 pieces.

Before the upgrade, the factory needed to configure three different winding machines to produce notch PFC coils, butterfly coils, and common-mode coils. Multiple devices occupied large workshop space, required more operators, and caused inconsistent winding precision across different equipment.

2. Production Pain Points

Multiple equipment investment: Separate machines for PFC, butterfly and common-mode winding increased procurement and maintenance costs.

Low production flexibility: Frequent production line switching was required for different order types, resulting in long setup time and low efficiency.

Unstable product consistency: Different machines had different tension control and turn-count accuracy, leading to high defective rates in high-frequency inductor batches.

High labor dependence: Semi-automatic equipment required manual feeding and parameter adjustment, increasing labor costs.

3. Custom Solution from Grewin

According to the client's diversified winding requirements, Grewin provided a fully automatic hook-type toroidal winding machine with multi-mode compatibility. The equipment realizes one machine for multiple uses, supporting three core winding processes in one device:

• Notch PFC winding
• Butterfly winding
• Common-mode winding

The machine adopts PLC servo control system and precise wire tension calibration, which is perfectly adapted to the magnetic ring size and wire diameter range required by the client's new energy inductor products. The factory can freely switch winding modes through the system program without replacing any mechanical fixtures.

Meanwhile, the equipment is equipped with an intelligent turn-count detection function, which automatically alarms and corrects errors to avoid defective coils caused by missing turns or wrong winding angles.

4. Final Production Results

After officially using the Grewin multi-functional toroidal winding machine, the client's production efficiency and product quality were significantly improved:

• Equipment cost reduced by 40%: No need to purchase three separate winding machines; one device covers all three production processes.
• Production flexibility greatly improved: Fast switching between PFC, butterfly and common-mode winding, suitable for multi-variety, small-batch and large-batch orders.
• Product defective rate dropped from 3.2% to 0.6%: Servo precise tension control ensures consistent coil inductance, wire arrangement and turns.
• Labor cost saved by 50%: Fully automatic operation realizes unattended winding, reducing manual intervention.
• Workshop space saved: Single-device integration replaces multiple traditional equipment, optimizing production layout.

5. Client Feedback

"Grewin's multi-functional toroidal winding machine solves our biggest pain point of scattered equipment and complicated process switching. The one-machine multi-mode design perfectly matches our diversified inductor production. The winding precision and stability fully meet new energy customer quality standards, and the after-sales technical support is very professional."

6. Conclusion

For manufacturers producing PFC inductors, butterfly coils and common-mode chokes, traditional single-function winding machines lead to high comprehensive production costs. Grewin's upgraded fully automatic toroidal hook winding machine integrates three mainstream winding technologies, helping electronic component factories achieve low-cost, high-efficiency and high-precision flexible production.

If your factory also needs multi-type toroidal coil production, contact Grewin Industrial Group to get a customized winding solution.