He begins with the basics of AC power systems, including their elements and architecture, moving to power generation systems, the power factor, including correction techniques, power transformers, capacitors, semiconductors, rectifier and filter circuits, power electronics, origins of AC line disturbances, power disturbance characterization, protection methods, the motor-generator set
, uninterruptible power systems, power conditioning devices, transient suppression (including at the circuit level and in facility wiring), grounding (practices, tower elements and system design in the facility), standby power systems, designing for tolerance of faults, energy efficiency, safety and protection systems.
A variety of solutions are available, the most complete being the motor-generator set
which can take raw power from a utility source and clean it up so that power variations will not affect plant operation.
His DC-to-AC power conversion method used rotary converters or motor-generator sets
, and some remained in use until recently.
"We used to drive high-speed elevators with DC; we converted the building's AC to DC using motor-generator sets
. Today, it's all done with solid-state devices," says Donoghue.
The lab currently keeps five motor-generator sets
: four from General Electric, each with a 2,100-horsepower motor driving a 1,500-kilowatt generator, and an Allis Chalmers setup with one 5,000-hp motor driving two generators that together produce a total of 3,500 kW.
Kato also manufactures motor-generator sets
and associated controls for power quality problems as well as frequency conversions.
An alternative to rotary motor-generator sets
as a d-c power source.
Predictive Maintenance (PM) is being applied to a wide range of rotating equipment: machine tools, spindles, electric motors, V-belt drives, gear drives, fans and blowers, turbines, motor-generator sets
, and rolling mills.
Three walking draglines, expected to begin digging by 2001 at Coal India Ltd.'s Dudhichua and Nigahi mines, will use General Electric motor-generator sets
for powering drag, hoist, and swing motions.
Available at all standard voltage to 600-v AC, sizes range from 10 to 1200 amps/phase and offer an alternative to rotary motor-generator sets
as a DC power source.