Title:
DC CIRCUIT BREAKER
Document Type and Number:
Japanese Patent JP2019204607
Kind Code:
A
Abstract:
To provide a DC circuit breaker in which a mechanical switch is opened after the load current is limited to a set value, even during a short-circuit incident.SOLUTION: A mechanical switch opening/closing a DC cable way and a current-limiting reactor having a winding wound around the magnetic core are placed in series between a DC power supply and a load, a DC current equal to a set value to be protected is fed continuously to the current-limiting reactor from a DC constant current source in the direction opposite to the load current, and in the load condition within the set value, the magnetic core is brought into magnetic saturation state, thus feeding the load current with less loss. When a current exceeding the set value begins to flow, ampere turn of the winding of the current-limiting reactor goes below a holding current and the current-limiting reactor becomes a high inductance, thus preventing the load current from exceeding the set value. The mechanical switch can be opened without generating arc discharge, by opening before the magnetic core saturates magnetically in the inverse direction due to back electromotive voltage. Furthermore, load on the DC constant current source can be reduced by providing a second winding in the current-limiting reactor, and feeding a set current thereto.SELECTED DRAWING: Figure 5
Inventors:
IIDA KATSUJI
Application Number:
JP2018097326A
Publication Date:
November 28, 2019
Filing Date:
May 21, 2018
Export Citation:
Assignee:
IIDA KATSUJI
International Classes:
H01H33/59; H01F37/00; H01H9/54; H01H33/16; H01H73/18