A switching arc plasma measurement experimental system using a magnetic sensor array

The measurement and analysis of the spatial morphology and dynamic characteristics of the electric arc plasma inside low voltage circuit breaker is an effective way to improve its breaking performance and modern testing techniques have been applied to the experimental study on switching arc plasma in recent years. However, these techniques usually need to destroy the extinguishing chamber wall and thus the original characteristics of the chamber will be changed. To solve this problem, this paper presents a novel measurement experimental system which is to infer the spatial morphology of the arc via measuring the magnetic field around the arc with the magnetic sensors array. This approach is a non-intrusive means so the chamber wall which has an important impact on the arc won't be damaged. The system has such advantages as a smaller size, lower cost and digital output and is fully applicable to experimental study on arc extinguishing system of low voltage circuit breakers. The experimental measurement system is designed in this paper and numerous experiments are performed. Results show that the magnetic field data sensed can infer the spatial morphologies of the arc in different stages.