Smart stations

For more than 80 years, transformer stations have connected the transmission grid with regional distribution grids, power plants and large industrial enterprises. If this power transfer is to function smoothly, the voltage has to be matched to the requirements of the customers. This “transforming” – from 380 to 110 kilovolts, for example – is performed by transformers.

As a result of the energy transition, wind and solar installations with heavily fluctuating generation patterns due to the natural whims of the weather feed electricity into the grid. This affects the voltage ­level in the grid. In future, the equipment installed in the transformer substations will play a key role in keeping the voltage level stable and, figuratively speaking, in regulating the traffic in the network. Amprion is preparing several transformer stations for these new tasks.

Stabilising the grid voltage

In order to build up the voltage in the AC grid, we need what’s called “reactive power”. This functions rather like a lubricant for the active or real power: the power that consumers can actually use. If the reactive power is too low, the voltage drops and the current flow is disturbed. If it is too high, less active power can be transported across the grid. Up to now, it was mainly the generators of large power stations that generated reactive power. However, with the phasing-out of coal and nuclear power, many of these generators are going offline. For this reason, Amprion is using more and more systems in transformer substations that absorb or generate reactive power as required.