Alternators: Form versus Random Wound 1

[rastus05]

I am looking for information on the relative benefits of form wound alternators compared to random wound alternators, for example failure rates, performance under fault conditions etc. My particular application is for low voltage (415V) alternators upto 1.2MW capacity for continuous operation.

Any information would be appreciated.

 

[alehman]

You may need to talk to a manufacturer for relative performance characteristics. Random stator winding is commonly used at low voltages to save cost. The disadvantage is that turn-to-turn voltages that the winding insulation must withstand are impossible to predict excatly. There may be some places where wires cross that are many turns apart electrically, causing relatively high voltage stress in the insulation. Insulation failures have been attributed to the higher stresses particularly where harmonic distortion is high and where transient overvoltages are a concern.

 

[electricpete]

http://www.kato-eng.com/fwrw.pdf

page 4 - advantages of form wound coils.

 

[jbartos]

Suggestion: Also visit

http://www.kato-eng.com/oveview.pdf

for: Form-wound winding on page 5

http://www.marathonelectric.com/generators/BROCHURE/DRLSPEC.pdf

for: Form-wound winding specifications

http://www.lincolnmotors.com/products/spike2.asp

for: Winding design
etc. for more info