| Brand | Switchgear parts |
| Model NO. | 220 kV intermediate straight through joint (ordinary type) |
| Rated voltage | 220kV |
| Series | YJJJI |
Structural design:
Adopting a prefabricated structure with built-in stress cone and shielding layer, the conductor connection adopts molding process, with low contact resistance and high mechanical strength
The outer sheath is double sealed with copper shell and fiberglass waterproof protection box, filled with flame-retardant and environmentally friendly waterproof casting agent, with a protection level of IP68
Electrical performance:
Rated voltage of 127/220kV, suitable for cable cross-section of 400~2500mm ², peak lightning impulse withstand voltage of 550kV (10 times for positive and negative polarities)
The long-term operating temperature of the conductor is 90 ℃, and it can withstand 250 ℃ during short circuit (lasting for 1 second)
Application scenarios
Urban power grid: used for direct connection of 220kV cable lines, such as tunnel and cable trench laying scenarios
New energy engineering: supporting wind power and photovoltaic booster station cable interconnection, requiring adaptation to environmental temperatures ranging from -40 ℃ to+50 ℃
Fault repair: When partial discharge exceeds the standard, the connector needs to be replaced (Example: A phase connector of a 220kV line had a discharge capacity of 11353pC due to a process defect, and the signal disappeared after replacement)
Technical Specifications
| Voltage level (kV) | 220 |
|---|---|
| Maximum operating voltage (kV) | 252 |
| Weight (kg) | ≈180kg (ordinary type) ≈500kg (waterproof type) |
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