Generation of Diffusion Arcs in Vacuum Circuit Breakers
Abstract
A model describing the generation of “diffusion” arcs in vacuum circuit breakers, the key mechanisms of which are thermo-auto-electronic emission and bombarding the cathode surface with positive ions and excited atoms, is presented. Recommendations on the design of electrodes with petals that serve for generating “diffusion” arcs and make it possible to decrease the contact drop-back force are given. The following conclusions have been drawn based on the study results: Thermo-auto-electronic emission and bombarding the cathode surface with positive ions and excited atoms are the key mechanisms governing the generation of “diffusion” arcs. Almost all ions colliding with the metal surface become neutralized. The use of tubular electrodes with petals in the design of vacuum arc quenching chambers makes it possible to decrease the warping of loop current and, hence, to reduce the contact drop-back force and create the heat tube operation conditions.
References
2. Ульянов К.Н. Физическая модель образования анодного пятна в сильноточной вакуумной дуге. — Теплофизика высоких температур, 2003, т. 41, № 2, с. 167.
3. Мещеряков В.П. Электрическая дуга большой мощности в выключателях. Часть II. Ульяновск: ОАО «Контактор», 2008, 429 с.
#
1. Raizer Yu.P. Fizika gazovogo razryada (Gas discharge physics). Moscow, Naula, 1992, 536 p.
2. Ul’yanov K.N. Teplofizika vysokikh temperature — in Russ. (Thermal Physics of High Temperature), 2003, vol. 41, No. 2, p. 167.
3. Meshcheryakov V.P. Elektricheskaya duga bol’skoi moshchnosti v vyklyuchatelyakh (High-power electric arc in circuit breakers). Part II. Ul’yanovsk, JSC «Kontaktor», 2008, 429 p.
