Research on the Self-Magnetic Field Distribution Characteristics of the Triggered Vacuum Switch With Multirod System

The motion of vacuum arc has an important effect on the performance of triggered vacuum switch with multirod (MTVS), and the motion characteristics of vacuum arc are closely influenced by the amplitude and profile of the magnetic flux density in the MTVS. A 3-D simulation model of the MTVS is built up, and the distribution of magnetic field of MTVS is calculated and analyzed. The simulation results show that the magnetic field in the interred gap has transverse component and longitudinal component. The simulation results also show that the transverse magnetic field is dominant when the MTVS is conducted by one single vacuum arc channel; however, the longitudinal magnetic field (LMF) is dominant when all the gap of the MTVS is conducted by vacuum arc. When the current flowing through the MTVS is up to 100 kA, the transverse component of magnetic field is up to 2.96 mT/kA, and the maximum value of the longitudinal component is up to 3.8 mT/kA, which meets the critical value of the LMF, which can keep the vacuum arc spreading. The influence of the structure parameters and the conductivity of vacuum arc on the magnetic field distribution are also analyzed. In addition, the high current capacity was tested, and the motion of vacuum arc in the MTVS has been investigated by the use of a high-speed camera. The experimental results agree well with the simulation results.