Vacuum circuit breaker’s solenoid force evaluation
29/12/2009
Deliverable 1
• Report on the compliance of the brand new trip coil and close coil to specification and their safety factors as derived from the laboratory experiments
EPE Switchgear -11 & 33KVClosing and Opening Coil
32 mm
Pull gauge
coilStopper block
Plunger
Trip hook/strike
16Kgf
232
2)(3.5)29(2(2205)7104 3.5A)F(32mm
2x
2Ai2Noμi)F(x,
EPE solenoid Force and Stroke EPE solenoid Force and Stroke RelationshipRelationship!!
μo is the Permeability of free spaceN is the number of coil turnsA is the effective cross sectionali is the max current x is the stroke length of the plunger
N.B. Data sheet of the coil attached in appendix
! A. E. Fitzgerald, Electric Machinery: The process, devices and systems of electromechanical energy conversion, McGraw Hill 1971
7.5Kgf
28
2)(3.5)23(2(350)7104 3.5A)F(8mm
2x
2Ai2Noμi)F(x,
ETAH solenoid Force and Stroke ETAH solenoid Force and Stroke RelationshipRelationship!!
μo is the Permeability of free spaceN is the number of coil turnsA is the effective cross sectionali is the max current x is the stroke length of the plunger
N.B. Data sheet of the coil attached in appendix
! A. E. Fitzgerald, Electric Machinery: The process, devices and systems of electromechanical energy conversion, McGraw Hill 1971
Stroke length (x) mm
Forc
e in
Kgf
EPE Solenoid Force & Amps vs Plunger positionEPE Solenoid Force & Amps vs Plunger position
Forc
e in
Kgf
TAMC) (ETAH) Solenoid Force & Amps vs Plunger positionTAMC) (ETAH) Solenoid Force & Amps vs Plunger position
Stroke length (x) mm
Photo Gallery
New Solenoid testing
Appendix – Solenoid Data Sheet