Neighbour inter-connection on cold end system for the operating units was carried out by setting corresponding pipes and valves

and then the cooling equipments of outage unit

such as natural ventilation cooling tower

air cooling tower and air cooling condenser

were fully utilized by the operating unit

therefore the cooling capacity was enhanced and the back-pressure decreased. Taking the three typical kinds of cold end system such as wet cooling system

indirect air-cooling system and direct air-cooling system for 600 MW units as the example

technical scheme for neighbour inter-connection on cold end system was summarized and the energy conservation effect of operating unit under rated load was obtained. The results show that

after the neighbour cold end system inter-connection

the unit back-pressure decreased by 0.9 k Pa at ambient air wet-bulb temperature of 22.5 ℃ for wet cooling system

by 9.57 k Pa at ambient air dry-bulb temperature of 33 ℃ for indirect air-cooling system

and by 5.55 k Pa at ambient air dry-bulb temperature of 33 ℃ for direct air-cooling system. The results can provide references for reducing back pressure and realizing energy saving for thermal power units.