1、Definition and Function

High Voltage Disconnector is a key equipment used in power systems to isolate high-voltage equipment. It opens and closes circuits under no-load conditions to ensure the safety of personnel and equipment during maintenance or repair.

Core functions:

Electrical isolation: Cut off the power supply to form a clear disconnection point.

Safe operation: Cooperate with circuit breakers to achieve power-off maintenance.

System refactoring: Switching the operating mode during the switching operation.

2、Classification and Structure

Classification Dimension Type Characteristics

According to the installation location, outdoor and indoor types have strong weather resistance (such as GW4 type), while indoor types have small volume (such as GN19 type).

According to the insulation method, the ceramic column, tank, and SF6 gas ceramic column structures are simple. The tank type (such as GW6 type) is suitable for high voltage levels, and SF6 gas insulation performance is superior.

Manual, electric, hydraulic manual type (CS17 type) is suitable for small capacities, while electric type (CJ type) is used for remote control.

Non grounded, single grounded, and double grounded types (such as GW7 type) are suitable for double busbar systems to improve grounding reliability.

3、Technical parameters

Typical parameter values description

The rated voltage of 35kV~1100kV determines the insulation distance and creepage distance, such as a 110kV insulator with a height of about 1.5 meters.

The rated current of 630A~6300A depends on the current carrying capacity of the wire. If the 6300A level requires multiple contacts to be connected in parallel.

Dynamic stable current of 50kA~200kA, withstand peak short-circuit current. If the current is 200kA, the contacts and transmission mechanism need to be strengthened.

The thermal stability current ranges from 20kA to 63kA (4s) and can withstand the thermal effects of short-circuit current. For 63kA level, the thickness of the copper bar should be ≥ 20mm.

The mechanical lifespan is determined by the reliability of the operating mechanism, ranging from 2000 to 5000 cycles. For example, hydraulic mechanisms require regular oil replenishment.