High voltage boost for trains

Paul Boughton

Test equipment manufacturer REO (UK), has launched a new high voltage direct current (HVDC) power supply for multi-function use.

The REOLAB 420 is a three phase DC high voltage power supply. Suitable for use as an auxiliary supply, the REOLAB 420 is used for the development and testing of frequency converters for railway engineering.

Input voltage for the unit is 3 x 400V line to line or 3 x 230V Line to neutral, with an output voltage from true zero to 12,000 VDC. Output current is 2x20 - 300A and output power is 100kW - 800kW as standard. Vector groups include Delta/Star/star/2 x B6U with a frequency range of 50/60Hz.

The REOLAB 420 complies with EC directive EN 61558-2-14 for power supplies with variable transformers. To further minimise the inherent dangers of working with high voltages, it offers an emergency-off circuit with external inputs and outputs as double-pole potential-free contacts for emergency-off circuits and safety circuits.

Because the unit is free of electromagnetic interference and maintains a constant residual ripple over the entire adjustment range of the DC output, the REOLAB 420 provides a control error of as little as 1%. The output current is protected against short-circuit and overload and has been doubled at half the DC voltage selectable.

Additional control of the supplementary equipment is attained by a 19" control unit, located away from the immediate vicinity of the HV supply unit.

Warning lights and additional connections for external warning systems increase unit safety. The REOLAB 420 has the ability to provide fast regulation of voltage variations and includes a built in discharge circuit for the intermediate-circuit capacitor. This is further enhanced using an earth trip with a compressed-air drive to short out and earth the DC output.

For more information, viist www.reo.co.uk