The research team led by Kim Hyok Chol, an institute head at the Faculty of Electrical Engineering, and Kim Nam Chol, a researcher at the Faculty of Mechanical Science and Technology, who designed and manufactured our style two-way high-speed circuit breaker for underground electric vehicles, is working for further achievements.
A two-way high-speed circuit breaker was designed and fabricated by combining a digital cut-off controller.
The device can achieve reliable high-speed cutoff even under severe operating conditions of underground electric vehicles. Accurate cutoff setting current and low mass and volume are other advantages of this device. In particular, successful bidirectional blocking is guaranteed.
The high-speed circuit breaker consists of a maintenance and release device for high-speed interruption, a blanking room, a locking control unit, and a contact system, which can sense both the current entering the electric vehicle and the current entering the grid during regenerative braking, so that the circuit can be shut down within 18 ms once an accident occurs.
The shutoff coil of the hold and trip device has no vibration-induced malfunction because there is no current flow during normal operation, and it takes less than 1ms to output a shutoff signal immediately after the current-cut signal from the current sensor enters the shutoff control device.
The turn-off controller has a double current sensing and a circuit to turn off analog and digital double, and the current setting has been simplified on a button.
The contactor is a two-point open type with an inclination angle of 45° and there is an arc-extinguishing component and a main contractor at each contactor. There is little electrical wear at the main contactor because there is no structural repulsion during turn-on.
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