Benefits, drawbacks and operational issues:Low base speed motors

Low base speed motors

For applications requiring operation with relatively slow base speed motors (10 or more poles), the limited number of slot combinations between the stator and rotor can lead to an acoustic resonant condition, and the associated very high levels of narrow band noise.

Many motor manufacturers will offer special windings using four pole or six pole motors with a reduced nominal frequency to avoid this phenomenon.

For a European 400 V electricity supply network, a requirement to

deliver full output at, for example 600 r/min, could be achieved with a 10 pole motor design, wound for 400 V at 50 Hz, or with a six pole motor wound for 400 V at 30 Hz.

Equally, because many motors are wound 400 V Delta/690 V Star (Wye), it is possible to provide full flux to a six pole design by connecting the motor in star and feeding with 400 V at 29 Hz base.

Related posts:

Pumps:Rotodynamic pumps
Compressed Air Transmission and Treatment:SYSTEM MAINTENANCE
Compressed Air Transmission and Treatment:Humidity control and Theory of coalescing filters
Particle degradation:Test rigs and data sources
Conveying characteristics:Single phase flow and The Darcy equation for pressure drop.
ROUBLESHOOTING PNEUMA TIC CIRCUITS:PNEUMATIC SYSTEM COMPONENT fAILURE MODES
MAINTENANCE OF HYDRAULIC SYSTEMS:ROOT CAUSE FAILURE ANALYSIS
RESERVOIRS, STRAINERS, FILTERS, AND ACCUMULATORS:fiLTRATION
Control components in a hydraulic system:Sequencing valve.
LINES, FITTINGS, AND SEALS:Hose Connection Side of Hose Fittings.
Process control valves and actuators:Flow control valves ,Actuators and Valve positioners.
The flapper-nozzle.
Air treatment:Stages of air treatment,Filters,Air dryers and Lubricators.
Fluid statics:Pressure at a point
PROPERTIES OF PURE SUBSTANCES:COMPRESSIBILITY FACTOR—A MEASURE OF DEVIATION FROM IDEAL-GAS...

Leave a comment

Your email address will not be published. Required fields are marked *