A high efficiency dc motor for operation in hostile conditions has been introduced by Astrosyn International Technology. The permanent magnet motor was initially developed to drive a hydraulic power pack for positioning the plough on a minefield clearance vehicle.
Its intended location in a confined, hot environment and its high power output of 6.2 kW meant that the motor's heat dissipation was a key consideration in its design. It is fitted with a metal cooling fan and a slotted body area over its brush gear. A thermal sensor and thermal cut-out are also incorporated.
The high efficiency design, with low losses and a low input current, is also important in minimising heat output.
A hollow shaft enables the motor to be close coupled with the hydraulic pump. The motor uses rare-earth permanent magnets and low-loss lamination steel, with novel designs for its construction and windings.
Operating from an 18-32 Vdc supply, the motor is designed to be powered from a motor vehicle, and its rugged construction makes it ideal for use in defence and other demanding applications.