LOW VOLTAGE APPARATUS ›› 2026, Vol. 0 ›› Issue (6): 67-75.doi: 10.16628/j.cnki.2095-8188.2026.06.008

• Electrical Design & Discussion • Previous Articles     Next Articles

Research on Arc Extinguishing Characteristics of DC Molded Case Circuit Breaker Based on Arc Voltage

ZHANG Senlin1, ZHANG Yihe1, WANG Bingqing2   

  1. 1 Shanghai Electrical Apparatus Research Institute(Group) Co., Ltd., Shanghai 200063, China
    2 Shanghai Electrical Apparatus Research Institute, Shanghai 200063, China
  • Received:2026-05-09 Online:2026-06-30 Published:2026-07-14

Abstract:

The short-circuit arc extinguishing conditions of low-voltage DC molded case circuit breakers remain unclear, and no quantitative evaluation criterion is available for the breaking performance of products equipped with different arc extinguishing chamber structures. To solve this problem, an evaluation method for short-circuit breaking performance of DC molded case circuit breakers based on arc voltage is proposed. Different target arc voltages are obtained by adjusting the quantity of arc plates inside the arc extinguishing chamber. It systematically studies the influence of average arc voltage on the arc extinguishing performance of circuit breakers under three test conditions: 1 500 V/5 kA, 750 V/20 kA and 750 V/10 kA. Test results indicate that the critical average arc voltage coefficients for reliable arc extinction under the three working conditions are 0.45, 1.13 and 0.89, and the corresponding required numbers of arc plates for the arc extinguishing chamber are 30, 34 and 30 respectively. The research conclusions can offer theoretical guidance for the design and optimization of arc extinguishing chambers of low-voltage DC molded case circuit breakers, and support rapid screening of the optimal matching scheme for arc extinguishing chamber layout.

Key words: DC molded case circuit breaker, short-circuit breaking, arc extinction condition, arc voltage

CLC Number: