HF DC link capacitors provide ultra-low ESL

TDK Corporation offers the ModCapTM HF, a modular capacitor concept for DC link applications that can work at extremely high switching frequencies. The six new power capacitors of the B25647A* series are offered for rated voltages from 900V to 1600V and cover a capacitance spectrum from 640µF to 1850µF. Depending on the type, the rated currents vary from 160A to 210A with a maximum permitted hot spot temperature of 90C.

Thanks to the ultra-low ESL value of just 8nH and its flat ESR vs Freq evolution that minimises losses even at high frequency, the capacitor is ideal for fast-switching SiC-based inverters. The very low self-inductance stops voltage overshooting on the power semiconductors when the current is shut off. Consequently, generally, no snubber capacitors are required.

In contrast to traditional cylindrical designs, the types are cubic with dimensions of 205mm x 90mm x 170mm. Thanks to this design, the capacitors fit completely into the new generation of power modules, enhancing compactness and maximising power density.

External materials comply with fire and smoke standard EN 45545-2 HL3 R23 and UL94 V-0, specially demanded for traction application. The American market especially requires UL recognition.

Typical applications include compact converters for traction, renewable energies, and industrial applications with high switching frequencies.