Dr. Kesorn Pechrach Weaver: Arc Control in Circuit Breakers: Magnetic forces in the contact area

Dr. Kesorn Pechrach Weaver: Arc Control in Circuit Breakers: Magnetic forces in the contact area: Magnetic forces in the contact area The conductors in circuit breaker and the arc are assumed to be threadlike. The anode is set on the...

Magnetic forces in the contact area

Magnetic forces in the contact area

The conductors in circuit breaker and the arc are assumed to be threadlike. The anode is
set on the moving contact and the cathode is on the fixed contact. The magnetic flux
density (B) is calculated by using a function of current and contact gap.
The experimental results provide the data of the arc current and the contact gap. The
magnetic flux density (B) is obtained from the magnetic force modeling. The
magnetic forces on arc root are calculated by using the relationship of the arc current,
contact gap and magnetic flux density (B).
At the point at which the arc root moves from contact region with contact opening
velocity 1-10 m/s, the contact gap is between 1.57 to 6 mm. Thus, the arc motion for
a contact gap less than 1 cm can be explained in terms of magnetic field

Ref: Arc Control in Circuit Breakers: Low Contact Velocity

Slow Contact Opening Circuit Breakers

Piezoelectrics in Circuit Breakers: Design and Test