Axial magnetic field vacuum interrupter: interrupting current-function of electrode area

The author provide a description of the interrupting current of an axial magnetic field (AMF) vacuum interrupter contact by a power function of the contact electrode area. This characteristic implies the sum of the interrupting currents of two or more partial contacts connected in parallel is higher than the interrupting current of a single contact with an electrode area equal to the sum of the electrode areas of the partial contacts. An algebraic description of the current increasing effect and of the associated effect of electrode area reduction is also presented. Numerical comparison is made of the effect of various characteristics on the extent of i.e. increase and electrode area reduction. Information is given on the state of practical employment of the findings and their perspectives