750-V DC/DC converter features high efficiency

Targeting light-rail and industrial applications, Powerbox has introduced PRBX ENR500D, a high-efficiency 750-VDC input DC/DC converter. The switching stage of the ENR500D DC/DC converter is based on an enhanced resonant topology, providing a high efficiency of 95% typical across the low (20%) to high (100%) load range. The 750-V DC/DC converter also is combined with the latest MOSFET technology and high-performance magnetics, said the company.

A variety of electrically-powered traction systems are used in rapid transit systems around the world with most metros operating from DC power either at 750 VDC with a third rail, or 1.5 kV with a third rail or from an overhead catenary, said Powerbox.  A 750-VDC voltage is very common in light rail, powering both the rolling-stock equipment and trackside signalling systems as well as in industrial equipment and other applications such as mining, added the company.

The ENR500D has a nominal input voltage of 750 VDC and operates within a range of 500 to 900 VDC. The nominal output voltage is set to 48 VDC, though it can be adjusted up to 60 VDC, said Powerbox. Nominal output power is 500 W constant across the temperature range of -40°C to 70°C in natural cooling conditions. Designed to reduce systems energy consumption, at no load the ENR500D input power is less than 5 W.

Designed for a range of light-rail and industrial applications, the ENR500D can be modified to offer other output voltages such as 12 V or 24 V. Different output powers can also be provided in optimized mechanical formats.

The ENR500D is designed to comply with the EN 50124-1 standard and Pollution Degree 2 (PD2) such as control cabinets in the driver’s cabin or passenger compartments. The ENR500D has ingress protection to IP20, and input-to-output double-reinforced isolation. The unit meets EMC emissions and immunity as specified in both EN 50124-1 and EN 50124-5.

The ENR500D is enclosed in an aluminum chassis with an integral heatsink. It measures 163 × 230 × 80 mm. All printed circuit boards have a protective coating.