Heat dissipation improvement and experimental verification of converter transformer valve side bushing based on water cooling technology

As the key equipment of the converter station, the UHV converter transformer valve side bushing simultaneously carries the high voltage and large current of the whole electric system during operation. With the gradual increase in the transmission capacity of Chinese power grid, the current carrying capacity of the bushing is also increasing, and the heating problem of the bushing is getting more and more serious. If the bushing runs at high temperature for a long time, it will accelerate the aging of components such as epoxy core and electrical contacts, which will affect the service life of the bushing. In this paper, according the thermal effect of the bushing's conductor, the heat dissipation ability of bushing is optimized. A design of using forced water cooling to dissipate heat from conductor is proposed. The effects of current amplitude on the thermal field distribution both of the traditional and water-cooled bushing were studied by 3D electromagnetic-heat-flow coupling method. The rationality and effectiveness of the optimal design were verified by the temperature rise test, which provides a solution for reducing the thermal effect of the bushing.