Evaluation Method for Interruption Capability of DC Circuit Breakers

This paper presents an evaluation method for the interruption capability of direct-current (DC) circuit breakers. We induced various hybrid types of DC circuit breakers (DCCBs) and proposed a suitable DC interruption test method to simulate the scenario of a short circuit occurring in a DC system during normal operation. To analytically estimate the interruption capability of the DCCB, we calculated the magnitude of the DC interruption current, rate of change of current (di/dt), and maximum transient recovery voltage (TIV) using an equivalent circuit model. To experimentally evaluate the interruption capability of the DCCB, we constructed a practical DC interruption test facility based on an equivalent circuit. The measured DC interruption test current was compared with the values calculated using the equivalent circuit model.