KYOCERA AVX FFLK Capacitors Target Traction DC Links

Uploaded image KYOCERA AVX has released the FFLK Series, a new range of traction-grade DC filtering film capacitors for industrial motor control and electric vehicle traction systems. The series is built for the DC link section of power electronics hardware, where capacitors have to deal with high voltage, high ripple current, elevated temperature, and repeated mechanical stress without becoming the weak point in the system.

FFLK is a traction-grade DC filtering film capacitor series used for smoothing and supporting DC bus operation in systems such as industrial drives and EV traction inverters. KYOCERA AVX says the new range is available in multiple cylindrical case sizes with voltage ratings from 900 VDC to 3,800 VDC and capacitance values from 25 µF to 3,020 µF, giving the series broad coverage across medium- and higher-voltage traction-oriented designs.

Built for Higher-Current DC Filtering

KYOCERA AVX is positioning the FFLK Series for traction environments where current handling, durability, and service life all need to hold up together. The company says the series can handle higher currents in smaller case sizes than comparable DC filtering capacitors, including parts from its own portfolio and competing suppliers. This becomes relevant in the DC link stage of traction and motor control hardware, where the capacitor bank has to absorb ripple energy, support switching behavior, and stay stable under thermal and electrical stress. A smaller capacitor with the required current capability can also help ease packaging pressure inside tightly packed power assemblies.

Dry and Wet Film Options Across a Wide Voltage Range

KYOCERA AVX has split the series into dry and wet metallized polypropylene constructions depending on voltage class. Variants using dry segmented metallized polypropylene film cover 900 VDC to 1,900 VDC, while wet metallized polypropylene versions, without free oil, extend from 2,000 VDC to 3,800 VDC. That gives designers a wider selection across different traction bus levels and industrial DC filtering requirements.

The mechanical format is cylindrical aluminum, with case heights from 130 mm to 340 mm and diameters from 85 mm to 116 mm. Connector options include female M6 or M10 terminations and male M8 or M20 terminations, along with a mechanical mounting bolt. In traction equipment, those details affect how easily the capacitor fits into the enclosure and how practical the installation is during assembly and service.

Controlled Self-Healing for Rugged Power Systems

One of the more important technical details in the announcement is the dielectric behavior. KYOCERA AVX says the FFLK Series uses a patented dielectric film that provides controlled self-healing. When a dielectric breakdown occurs, the adjacent electrodes are vaporized in a controlled way that isolates the fault site. The goal is to prevent a short circuit and avoid catastrophic failure while allowing the capacitor to continue operating with only gradual capacitance loss over time.

This is especially relevant in traction and industrial inverter systems, where capacitors are exposed to repeated electrical stress over long service periods. KYOCERA AVX also rates the series for 100,000 hours when used within its defined operating conditions, including temperatures from -40 C to +95 C and a 70 C hot spot temperature. The series is further described as compliant with relevant IEC, UL, EN, and RoHS requirements for power electronics, railway use, environmental testing, and flammability.

Positioned for Demanding Traction Applications

KYOCERA AVX is also comparing the FFLK Series with commercial-grade DC filtering solutions and aluminum electrolytics used in similar roles. According to the company, the new range is intended for applications that demand higher surge voltage tolerance, lower ESR, higher RMS current capability, and longer service life.

For designers working on traction inverters, motor drives, and related DC link hardware, that is where the series is intended to sit. The FFLK range is aimed at demanding applications where electrical stress, environmental conditions, and operating lifetime place more pressure on the capacitor choice.

Learn more and read the original announcement at www.kyocera-avx.com

Technology Overview

The KYOCERA AVX FFLK Series is a traction-grade DC filtering film capacitor family for industrial motor control and EV traction systems. The series spans 900 VDC to 3,800 VDC, offers capacitance values from 25 µF to 3,020 µF, and uses dry or wet metallized polypropylene film in cylindrical aluminum cases.

View the FFLK Series datasheet.

Frequently Asked Questions

Are FFLK capacitors designed for EV traction inverters?

Yes. KYOCERA AVX positions the FFLK Series for EV traction systems and industrial motor control DC filtering applications.

What voltage range is available in the FFLK Series?

The series spans 900 VDC to 3,800 VDC, depending on the construction type.

What type of film dielectric does the FFLK Series use?

The series uses dry segmented or wet metallized polypropylene film, depending on the voltage-rated version.