Our SD series of solid state frequency converters are derived from our long experience in the design and manufacture of rectifiers, inverters, UPS systems and frequency converters. This 400Hz frequency converter range includes outdoor all weather units that can be used for military airfield and airport applications. The compact converters can be fixed to the gantry of a passenger loading bridge, can be hung underneath the walkway, or the vertically configured systems can be installed at a convenient place close to aircraft parks. We also have indoor versions of the ground power unit (GPU) for use in maintenance hangars, avionics workshops, hard shelters and simulator applications.
The SD series of frequency converters is available in 60kVA with a single output, or 90kVA and 120kVA with one or two output circuits suitable for a wide bodied aircraft. The 180kVA/380 unit is supplied with two 90kVA outputs and is configured so that two 180kVA converters can support the ground power requirements of an Airbus A380.
This frequency changer is designed for connecting to the normal three phase 50Hz (or 60Hz) mains power source and delivers an output of 200V three phase 400Hz power to the aircraft through a single contactor output stage in sizes up to 90kVA or through a circuit breaker when used indoors. The higher powered units are supplied with two output circuit breakers, interlocks and with two contactors for the outdoor versions.
These ‘point of use’ GPUs can be supplied with an optional built in NBT feature that allows the converters to synchronise with the on board aircraft power system so the lights, air conditioning system and the avionics continue operating during the change over from aircraft power to the external converter power.
The SDM-M series is the mobile version of this range. The all weather converter is supplied on a trailer as a versatile mobile GPU with 400Hz output up to 180kVA, and as an option can be configured as a combination converter with a secondary output of 28V DC 600A.
Optional Features:
- Military class rugged construction
- Ingress protection IP42 and IP54
- Extended temperature range: from -20C to +50C
- Dual output for connecting two cables and two aircraft connectors
- Parallel load sharing configuration for multi-modules
- Output contactor control interface from the aircraft connector
- Aircraft interlock bypass circuits
- No break power transfer to aircraft power circuit
- Line drop compensation
- Remote voltage sensing and control for long cable lengths
- Mobile version on towable trolley or trailer
- Horizontal style for mounting under passenger loading bridge
- Secondary output of 28V DC, 600A for battery charging and helicopter engine starting
