multicoil

Multicoil is a term used to describe an assembly that contains two or more coils (windings) that are electromagnetically coupled, usually around a shared magnetic core. Unlike a single-coil component, a multicoil device can implement multiple voltage levels, isolation between circuits, or distributed energy transfer. The coils may be connected in series or parallel, or they may serve different functions in a system, such as primary and secondary windings in a transformer, or multiple secondary windings for different voltages in power supplies. In wireless power transfer, planar or air-cored multicoil arrangements can optimize coupling at target distances. In automotive or industrial applications, multicoil configurations are common in coil assemblies where several ignition coils or inductors are integrated into one housing to improve packaging and control.

Design considerations include achieving sufficient mutual coupling between coils while controlling leakage inductance, managing parasitic capacitances, selecting core material and geometry for the desired frequency and power level, addressing thermal dissipation, and ensuring insulation and safety compliance. Electrical characteristics such as coupling coefficient, leakage inductance, quality factor, and saturation behavior are key factors in performance.

Manufacturing approaches vary from wound bobbins and laminated cores to printed circuit board planar coils, depending on frequency and power. The term multicoil is often used interchangeably with multi-winding transformer, coil array, or coil pack, depending on context and application.