Wiki article · Collection 03

Coil Manufacturing

Engineering reference on Coil Manufacturing for wireless power system design, integration, and deployment.

6 minArticle 16/50Coil Design

Coil Manufacturing — educational diagram — Fig.: Educational diagram for “Coil Manufacturing”.

Coil manufacturing spans hand-wound litz on bobbins, automated toroid/spiral winding, PCB etch with heavy copper, and stamped foil assemblies. The method sets tolerance on inductance, unit cost, and failure modes. Fleet-scale AGV programs need process capability (Cp/Cpk) on L and R, not single golden samples.

Wireless power coils are high-current RF components — cosmetic consistency matters less than turn count, strand integrity, and termination quality.

01Process options

Litz spiral wound and potted: common for high-power TX/RX discs.
PCB coil: excellent repeatability, watch copper thickness and via resistance.
Preformed copper sheet: good for thick conductors, tooling cost upfront.
Hybrid: PCB for low-power sense windings, litz for power path.

Coil Manufacturing — supporting diagram — Fig.: Supporting illustration for “Coil Manufacturing”.

02Quality controls

100% or statistical electrical test at frequency (L, Q, R_ac). Visual inspection for strand nicking and ferrite cracks. Potting cure logs — incomplete cure allows wire movement in service. Serialization linking coil test data to pad serial number for field traceability.

03Supply chain

Second-source litz and ferrite where program volume warrants.
Document allowed substitutes with re-validation gates.
Lead times for custom ferrite tiles often dominate schedule — parallel-path early.