Current Interrupting Capability of Switch Equipped with Deion Plates and Electromagnetic Force Applied to the Arc

The present paper reports the measurements of the arc interrupting capability and calculation of the electromagnetic force of an arc quenching chamber equipped with deion plates,. The interrupting capability of an ac current was measured to be about 350 A for four plates made of copper (condition named C1–4). Locating four deion plates made of iron at the same intervals (condition I1–4) led to the interrupting capability to increase to about 600 A. In contrast, positioning the same number of the plates at a wider interval (condition I1,3,5,7) resulted in further increase in the capability to 900 A. Calculation of the magnetic‐flux density distribution in the cross‐section of a cylindrical conductor revealed that placing the four plates produced more asymmetrical distribution for the condition I1,3,5,7 than for I1–4. Further calculation of the electromagnetic force applied to the conductor showed that arranging the deion plates gave a higher force under the condition I1,3,5,7 than under I1–4.