What information do you need to quote custom transformers or power inductors?

We usually need the topology and schematic, operating voltages and currents, switching frequency, isolation and safety requirements, expected ambient and cooling concept, plus any mechanical limits and connector preferences.

Can TPS help if I only have a target inductance or turns ratio?

Yes. Many projects start with functional targets rather than finished drawings. Our team can propose winding structures, core types and insulation systems that meet your requirements and are manufacturable at the intended volumes.

Which standards do your custom magnetics support?

TPS designs magnetics to fit into systems that may fall under industrial, automotive or medical standards, depending on the end product. We align hipot levels, creepage and clearance with the safety categories specified by the customer.

Can you pot or encapsulate transformers and inductors?

Yes. Where required, TPS offers resin potting or encapsulation to reduce vibration and audible noise, improve dielectric strength and protect against moisture or contamination.

Do you supply magnetics on their own or only as part of larger assemblies?

Both options are available. Some customers purchase magnetics as stand-alone components, while others prefer TPS to combine them with PCBs, coolers, harnesses and cabinets so that everything is tested together before shipping.

For power electronics and industrial OEMs that need more than catalogue transformers or inductors.

Custom transformers and power inductors for industrial and e-mobility electronics

TPS designs and manufactures custom transformers, power inductors and common mode chokes for power supplies, drives, battery systems and charging infrastructure. Instead of buying loose parts, you can source magnetics together with PCBA, coolers, metal parts and cabinet wiring as tested assemblies.

On this page we explain what types of magnetics we build, how our coil winding services work, and how custom magnetics fit into complete power electronics manufacturing.

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Why custom transformers and power inductors matter

Standard catalog magnetics are ideal for evaluation boards and simple power supplies. But once a design moves into production, you often need custom transformers and inductors that match your topology, switching frequency, efficiency targets and industry standards.

In a switching power supply or converter, power inductors store energy and filter current ripple, while transformers provide isolation and voltage conversion. In many EV, renewable and industrial applications, magnetics also influence EMC, thermal behaviour and overall system size.

Optimised performance: custom magnetics let you tune losses, leakage inductance and temperature rise to your exact duty cycle.
Mechanical fit: winding windows, creepage distances and terminals are laid out for your PCB, busbars and cabinet layout.
Compliance and reliability: insulation systems, hipot levels and materials are matched to the relevant safety and industry requirements.

In many converters, custom transformers handle isolation and voltage conversion, while power inductors provide energy storage and filtering on the output or intermediate stages.

TPS winding goods capabilities

TPS operates a dedicated winding area where custom transformers, power inductors and common mode chokes are produced as part of our EMS stack. The same QA and traceability used for PCBA and cabinet wiring applies to magnetics.

Coil winding services and machine base

Automatic coil winding machines for medium- to high-volume parts with controlled turns, tension and layer patterns.
Programmable toroidal winding machines for high-current chokes and toroidal transformers.
Manual and semi-automatic equipment for prototypes, specials and lower-volume industrial applications.

Conductor and core options

Copper or aluminium wire in round, rectangular or litz constructions.
Ferrite, laminated steel, nanocrystalline and powder cores selected to match frequency and loss targets.
Bobbin, toroidal, E-core, U-core and planar constructions depending on footprint and power level.

TPS turns your electrical and mechanical specifications into wound, impregnated and tested custom magnetics that can be shipped alone or as part of larger assemblies.

For a deeper overview of the winding area, see the Winding Goods section on our electronic manufacturing services page.

Types of custom magnetics we build

TPS focuses on custom transformers and inductors for power electronics rather than small-signal or RF-only parts. Typical device families include:

Custom transformers

Isolated power transformers: flyback, forward, full-bridge and resonant topologies for AC/DC and DC/DC converters.
Gate-drive and auxiliary transformers: small transformers for driving high-side switches and providing auxiliary rails.
High-power magnetics: multi-kilowatt transformers for industrial drives, chargers and rectifiers, designed for forced-air or liquid cooling.

Power inductors and chokes

Energy-storage inductors: buck, boost and PFC inductors designed for defined ripple current and saturation margins.
Output filter chokes: smoothing inductors for inverters and DC buses, often built on toroidal or E-cores.
High-current bus inductors: custom busbar-integrated inductors for compact high-power converters.

Common mode chokes and EMI magnetics

Common mode chokes: wound components that attenuate high-frequency noise on power or data lines while passing the desired differential signal, helping systems meet EMI limits.
Line reactors and filters: inductive components that reduce current ripple and protect drives or power supplies from grid disturbances.

Magnetics can be delivered as individual parts or combined with PCBA and cabinet assemblies so you receive fewer part numbers and tested sub-systems.

Manufacturing: coil winding, impregnation and testing

Reliable magnetics are defined not only by the electrical design but also by how the coils are wound, insulated and tested. TPS uses controlled processes for every step.

Coil winding and assembly

Layer and section control: winding programs that enforce turns-per-layer, insulation margins and start/finish routing for repeatable inductance and leakage values.
Multi-wire and litz winding: parallel conductors or litz wire where skin-effect and AC losses need to be minimised at higher frequencies.
Leadout and termination: tinned leads, PCB pins, lugs or custom terminals designed for fast assembly into your system.

Vacuum impregnation and potting

Varnish impregnation: atmospheric or vacuum impregnation to improve dielectric strength, mechanical stability and moisture resistance.
VPI / vacuum pressure impregnation: deeper penetration of resin into windings for high-voltage or high-reliability applications.
Potting and encapsulation: filled or unfilled resin systems to protect coils from vibration, humidity and contamination, and to reduce audible noise.

Electrical and functional testing

Hi-pot and insulation tests: dielectric withstand tests between windings and core or between primary and secondary, according to the working voltage and applicable standards.
Inductance and loss measurement: verification of inductance, turns ratio, leakage and core losses at representative test conditions.
Routine and sample tests: 100% checks on safety-critical parameters and sample tests for extended characteristics, documented under our QA system.

From specification and coil winding through impregnation and testing, TPS applies controlled processes so custom transformers and inductors behave consistently from prototype to series production.

Industry applications for custom transformers and inductors

Custom magnetics from TPS are used in the same sectors as our power electronics manufacturing.

Industrial power and automation

AC/DC and DC/DC power supplies for factory automation, motion control and test equipment.
Drive input and output filters, line reactors and auxiliary supplies inside control cabinets.
Magnetics for laboratory power racks and programmable supplies used in R&D and test benches.

Automotive and e-mobility electronics

Custom transformers and inductors for on-board chargers and DC/DC converters in electric vehicles.
Common mode chokes and EMI magnetics for charging infrastructure and vehicle test systems.
Gate-drive transformers and current-sense transformers in traction inverters and battery test equipment.

Battery systems, DC power and energy storage

Magnetics for battery chargers, DC distribution and backup systems.
Isolation and filtering components in power shelves and modular DC racks.
Auxiliary transformers and inductors in battery management and monitoring systems.

Medical and laboratory equipment

Custom transformers for diagnostic instruments, imaging systems and lab automation equipment.
Inductors and chokes in low-noise power supplies for sensitive measurement circuits.

To see how magnetics connect with full systems, explore our electronic manufacturing services, integration solutions and EMC & safety testing pages.

How to start a custom magnetics project with TPS

You can involve TPS at different stages – from early feasibility to ready-for-production drawings. For a meaningful discussion we typically need:

Electrical requirements: topology, input and output ranges, switching frequency, power level and efficiency targets.
Insulation and safety data: required isolation voltage, creepage and clearance distances, and target standards.
Mechanical constraints: maximum footprint and height, connector type, cooling concept and mounting details.

FAQ about custom transformers, inductors and chokes

What information do you need to quote custom transformers or power inductors?: We usually need the topology and schematic, operating voltages and currents, switching frequency, isolation and safety requirements, expected ambient and cooling concept, plus any mechanical limits and connector preferences. If you already have magnetics models or reference parts, sharing them helps speed up the review.
Can TPS help if I only have a target inductance or turns ratio?: Yes. Many projects start with functional targets rather than finished drawings. Our team can propose winding structures, core types and insulation systems that meet your requirements and are manufacturable at the intended volumes.
Which standards do your custom magnetics support?: TPS designs magnetics to fit into systems that may fall under industrial, automotive or medical standards, depending on the end product. We align hipot levels, creepage and clearance with the safety categories you specify and can document tests as part of your compliance package.
Can you pot or encapsulate transformers and inductors?: Yes. Where required, we offer resin potting or encapsulation to reduce vibration and audible noise, improve dielectric strength and protect against moisture or contamination. This is especially useful for outdoor, high-voltage or high-reliability applications.
Do you supply magnetics on their own or only as part of larger assemblies?: Both options are available. Some customers purchase magnetics as stand-alone components, while others prefer TPS to combine them with PCBs, coolers, harnesses and cabinets so that everything is tested together before shipping.