Investigation on the Magnetic Arc Control of Multi-Break VCBs

In order to obtain the effective magnetic arc control method, the synergy effect and the demand of the magnetic arc control in the multi-break VCBs is analyzed. The vital mechanism is the synergy interaction between the dynamic voltage distribution (DVD) and dielectric recovery strength (DRS). Then the test platform of the magnetic arc control in multi-break VCBs is set up and the magnetic arc control system is designed. The influence of the pulse width, control moment and magnetic field on the vacuum arc development and the post arc characteristic is investigated. The different combinations of externally applied AMF are applied to the double-break VCBs to analyze the effect of the AMF arc control on the DVD. The interaction between the magnetic arc control and the post arc characteristic is obtained and the influence of the post arc characteristic on the DVD and DRS is gained. The test results indicate that the mechanism of the magnetic arc control in multi-break VCBs is that the DVD and DRS is affected by the post arc characteristic which is influenced by the arc memory of the magnetic arc control in arcing process. The paper is useful to optimal design of the special serial VCBs and the magnetic arc control of multibreak VCBs.