Abstract: Some embodiments in the present disclosure provide a cooling apparatus for mold transformers, which may be installed at opposite sides of a lower portion of the mold transformer having a first space formed between a core and a low voltage coil and a second space formed between the low voltage coil and a high voltage coil, characterized in that the cooling apparatus comprises a duct extending from the cooling apparatus in a direction toward the mold transformer, a discharge port of the cooling apparatus is configured to direct toward lower ends of the low voltage coil and the high voltage coil, so that cooling air discharged from the duct is injected into the inside of the first and second spaces.

Abstract: Provided is a gas circuit breaker. The gas circuit breaker includes a fixed part, a movable part, a piston, and a double compression mechanism. The fixed part includes a fixed arc contact and a first fixed contact maker. The movable part includes a movable arc contact selectively making contact with the fixed arc contact, a cylinder in which the movable arc contact is disposed, and a second fixed contact maker guiding a movement of the cylinder. The piston is disposed in the second fixed contact maker. The double compression mechanism is configured to move the piston in a direction opposite to a moving direction of the movable part when the movable part is moved to separate the fixed arc contact and the movable arc contact for interrupting a fault current.

Abstract: Provided is a gas circuit breaker. The gas circuit breaker includes a fixed part, a movable part, a piston, and a double compression mechanism. The fixed part includes a fixed arc contact and a first fixed contact maker. The movable part includes a movable arc contact selectively making contact with the fixed arc contact, a cylinder in which the movable arc contact is disposed, and a second fixed contact maker guiding a movement of the cylinder. The piston is disposed in the second fixed contact maker. The double compression mechanism is configured to move the piston in a direction opposite to a moving direction of the movable part when the movable part is moved to separate the fixed arc contact and the movable arc contact for interrupting a fault current.