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Intelligent relay power supply for extra long city (highway) tunnel engineering

The total length of the tunnel is 1.17km, and the distance between the substation outside the tunnel and the tunnel entrance is 0.35km. The power supply distance is about 1.5km, and the investment required for building a substation in the middle of the tunnel or using a thicker distribution cable scheme is tens of millions.
By adopting an intelligent relay power solution, while meeting the same technical requirements for reliability and safety, the investment only needs to be in the hundreds of thousands.