1. High Speed Switch Main Parameters:
252kV High speed switch technical parameters:
| Time | Opening | Short arcing | Arcing range | Total breaking
time |
| Traditional
switch |
27 | 11-12 | 9 | ≤50 |
| High speed switch | ≤8 | ≤8 | 9 | ≤25 |
550kV High speed switch technical parameters:
| Time | Opening | Short arcing | Arcing range | Total breaking time |
| Traditional switch | 19-23 | 13-15 | 9 | ≤50 |
| High speed switch | ≤7 | ≤8 | 9.8 | ≤25 |
2. Advantage on High Speed Switch
The transmission power of grid is determined by the safety and stability of short circuit fault. The longer the time of line fault removal, the more difficult for the system stability. High speed switch can improve the system stability effectively . At the same time, the high speed switch can quickly remove the fault current, shorten the overload duration of the transformer, prevent the coil temperature from being too high, slow down the aging speed of insulation, so as to reduce the impact of the fault current on the transformer and damage, reduce the transformer burn probability.
3. Project Application
The first 252kV product was put into operation in December 2020 and passed the artificial short-circuit current test on site. The total breaking time was 20.1ms
(including relay protection time). The reliable breaking ability of 252kV fast switch has been verified, and the product has been operating safely so far also.
