Research on Breaking Arc Characteristics of Circuit Breakers Under Harmonic Current

EasyChair Preprint 6369

Abstract

In recent years, a large number of new energy sources such as wind power and photovoltaics have been continuously connected to the grid, and the power system has gradually shown a trend of power electronics. The problem of excessive harmonics has gradually become prominent, which has greatly affected the safe and stable operation of the power grid. There is a risk of failure to break the circuit breaker when the harmonic is exceeded. Studying the influence of harmonics on the breaking of switchgear and formulating effective countermeasures are important technical measures to ensure the safe and reliable operation of the power grid. In this paper, by establishing an arc magnetohydrodynamic model under harmonic currents, the circuit breaker breaking characteristics under harmonic currents are developed. Studies have shown that the existence of harmonics in the system will cause the current change rate di/dt to increase significantly at the time of the current zero-crossing point in the circuit breaker opening process, and with the increase of the harmonic amplitude, the di/dt becomes larger; Existence will cause the arc voltage amplitude and rate of rise before zero crossing during the circuit breaker opening process to decrease; the presence of harmonics will cause the temperature of the arc extinguishing chamber to rise during the circuit breaker opening process; the above harmonics will affect the opening process It is not conducive to the successful opening of the circuit breaker.

Keyphrases: Arc model, arc characteristics, harmonic

@booklet{EasyChair:6369,
  author    = {Kai Liu and Ruihai Li and Zaixing Peng and Jiali Chen and Xiaoyong Yu and Shaonan Chen},
  title     = {Research on Breaking Arc Characteristics of Circuit Breakers Under Harmonic Current},
  howpublished = {EasyChair Preprint 6369},
  year      = {EasyChair, 2021}}