Inverter & Power Conversion Busbar Solutions

New power architectures — EVs, consumer electronics, renewables — keep expanding the use of AC-DC and DC-DC converters and DC-AC inverters. Designs push switching frequencies higher to shrink size and save board space, which makes thermal management an increasing challenge, while the converter location is often extremely space-limited. In the commutation loop of any inverter, every nanohenry of stray inductance shows up at switch-off as voltage overshoot: V = L × di/dt. That overshoot drives power component ratings, switching frequency and losses, which is why the DC link is designed around the busbar.

A laminated busbar is built for exactly this. Inductance of a conductor depends on its shape and the proximity of opposite current paths; the lowest-inductance geometry is given by parallel planes — the structure of a laminated busbar. To minimize inductance, opposing conductors are brought extremely close, with reference designs holding dielectric spacing under 100 µm between opposing layers. The busbar distributes current from the DC-link buffer capacitors to the IGBT/MOSFET modules through defined, low-inductance paths, and soldering or bolting capacitors as close as possible to the device terminals eliminates the long individual leads that would otherwise extend the commutation loop.

Partial discharge is the second control axis, especially as bus voltages climb. Trapped air bubbles at insulation-to-conductor and insulation-to-insulation interfaces initiate PD; production verification keeps it below the industry reference level of 10 pC, even at test voltages above the operating voltage. We walk through both control axes in our engineering notes on low-inductance busbar design and on partial discharge in busbars.

Where the current sits between a PCB and a full laminated bar — roughly 100–500 A — reference designs use thick-copper hybrid construction (400–800 µm copper), wave-solderable like a PCB while carrying busbar-level current. We build these DC links as 1–6+ layer C11000 copper assemblies, tin-plated and edge-sealed, part of our power electronics busbars family; the same low-inductance, PD-controlled geometry carries over to aerospace converter DC links when platforms move into airborne or defense environments. Every DC link ships with lot-by-lot hipot, PD and dimensional test records. Send us the module datasheet and capacitor layout — DFM review within one business day.