A HOMOPOLAR GENERATOR FOR HIGH CURRENT LOW VOLTAGE D.C. SUPPLY

Technical Report · Fri Nov 30 04:00:00 EST 1951

OSTI ID:4322394

Watt, D A

A general theory of Homopolar Generator Design is given, including estimation of brush friction loss and conditions for stable operation when conducting large currents. A tabulated survey of the principal ohmic losses and power absorbed by brush friction is given for a 10kW generator. Three operating conditions are considered, ranging from 4,000 amps at 2.5 volts to 16,000 amps at 0.625 volts. Brush stability is examined and over-all merits of sodium-potassium alloy and mercury as the brush liquid are considered. It is shown that there are designs of 90 to 95% efficiency using mercury or alloy brushes, but mercury is to be preferred as it ensures greater brush stability under momentary overload and involves fewer development problems. A design of approximately 90% efficiency with mercury brushes is detailed. lt has a rotor of radius 16 cms., length in gap 6 cms., and is run at 935 rpm with gap flux 10,700 gauss to give 10,000 amps at 1.0 volt and at760 rpm, 6,000 gauss, to give 16,000 amps at 0.625 volt. (auth)

• Research Organization: Gt. Brit. Atomic Energy Research Establishment, Harwell, Berks, England
• NSA Number: NSA-12-011481
• OSTI ID: 4322394
• Report Number(s): AERE-ED/R-1843
• Country of Publication: United Kingdom
• Language: English

Related Subjects

CURRENTS
ELECTRIC POTENTIAL
GENERATORS
HOMOPOLAR GENERATORS
INTERMETALLIC COMPOUNDS
LOSSES
MAGNETIC FIELDS
MERCURY
PHYSICS
PLANNING
POTASSIUM ALLOYS
POWER
POWER PLANTS
SODIUM ALLOYS
STABILITY