Transducers Bridge The Gap At Brush Traction

Key to improvements are reliable converted engine governors for the repower packages, which use Penny + Giles LVDT technology to bridge a gap between the old and the new control and power equipment whose designs were conceived a few decades apart.

The engine governors fitted to older diesel-electric locomotives are electro-hydraulic control devices. The various types, produced by different manufacturers, can be up to 40 years old and all have to be converted by Brush engineers with very little support from the OEMs who produced them, as most no longer exist.

Since 1998, Penny + Giles LVDTs have been used to re-engineer locomotives that are having old-style hydraulic sub-systems ‘changed-out’ and replaced with new electronic sub- systems. The new systems provide faster feedback signals, allowing the locomotive’s new electronic control system to respond to power changes much more quickly than the existing hydraulically controlled system.

The Penny + Giles LVDTs are installed in engine governors – electro-hydraulic engine control devices found on all older diesel- electric locomotive engines. The governors control the power output of the diesel engine based on feedback from the LVDTs.

The Penny + Giles LVDTs and custom-designed transducer driver electronics provide the demand signal from the governor to control the traction alternator or generator, which in turn provides power to the traction motors. The rugged construction of the LVDTs makes them ideal for extremely hostile locomotive environments, where they are running in hot oil, which is another reason why they are specified.