The departure from fossil fuels and the massive expansion of wind and solar plants is only one side of the coin when it comes to the future of the grids. The other is that at the same time the demand for electricity is rising rapidly. Not only because mobility and heat are becoming electric, but also because more and more people need electricity to live: According to UN forecasts, the world's population will rise to around 10 billion by 2060. But if more electricity is to flow, we need more lines and larger transformers.
Time of the giants: XXL transformers for more power
The energy transition, sector coupling and population growth are causing the demand for electrical energy to grow enormously. The trend is therefore toward ever larger and more powerful transformers. Three areas are particularly affected by this.
Time of the giants: XXL transformers for more power
The energy transition, sector coupling and population growth are causing the demand for electrical energy to grow enormously. The trend is therefore toward ever larger and more powerful transformers. Three areas are particularly affected by this.
Reinhausen has developed an on-load tap-changer that makes such high-performance applications possible: VACUTAP® VRL® - the world's most powerful vacuum switch. Until now, the rated current was 1,300 amperes; the new switch can handle 3,200 amperes, which is more than double the rated current. This is how Reinhausen makes the construction of ever larger transformers possible in the first place. This is particularly interesting for three applications.
Direct current transmission with HVDC transformers
Direct current transmission with HVDC transformers
High-voltage direct-current transmission (HVDC) is a central adjusting screw for the energy turnaround. This is because climate-friendly electricity is usually generated far away from urban centers and large industrial consumers: on the high seas or in desert regions. Using direct current technology, the energy can be transported over long distances with low losses and can also be exchanged between countries that have a different grid frequency. To transport more and more solar and wind power, ever greater transmission capacities are needed. For the converter stations that convert the direct current into alternating current at the ends of the lines, this means significantly higher voltages. This is why ever larger HVDC transformers and ever more powerful tap-changers are needed here.
The size of HVDC transformers on the collection platforms is increasing. (©iStock)
The new VACUTAP® VRL® in figures
3200 A
Maximum rated current
6000 V
Maximum step voltage
10000 kVA
Maximum switching capacity
Stabilizers in the grid: phase-shifting transformers
Stabilizers in the grid: phase-shifting transformers
With the growth of renewable feeders, volatility in transmission grids is also increasing. Depending on weather conditions, overloads occur on individual lines without further grid expansion. In order to keep the grid stable, the generated electricity cannot be used and expensive redispatch measures are required. Power flow management is therefore becoming increasingly important. Phase-shifting transformers help to increase the transmission capacity of the existing infrastructure by shifting the overload from a line so that the network is better utilized. Here, too, the equation applies: If the power from sun and wind increases, the phase-shifting transformers must also become larger. One example of this is the largest and most powerful phase-shifting transformer used to date by the German grid operator Amprion. The VACUTAP® VRL® already switches in it.
Read more in ONLOAD
The VACUTAP® VRL® already switches in probably the largest phase shifter in the world.
High power applications: Transformers for industry
High power applications: Transformers for industry
Furnace transformers in steel mills have to handle enormous amounts of energy. They ensure that the temperature curve required for the melting process in the electric arc furnace is maintained. The central actuator for controlling this is the tap changer, which regulates the voltage around the clock. To illustrate the dimensions: It switches more frequently in a few weeks than it would in a normal grid transformer in 20 years. With up to 300,000 switching operations, the new VACUTAP® VRL® is maintenance-free and thus equipped to meet such enormous demands. And the high-performance switch is not only of interest to the steel industry: other energy-intensive applications in which large transformers are needed include cement plants, copper and aluminum production, or electrolysis applications, such as for the production of hydrogen.
High-performance transformers are essential for steel production. (©iStock)
A masterpiece
The VACUTAP® VRL® is an innovative solution for controlling extreme currents and magnetic fields. The developers at Reinhausen were able to draw on over 30 years of experience in vacuum technology for its realization. The VACUTAP® VRL® offers numerous advantages for both transformer manufacturers and network operators.
Advantages for the design of high power transformers:
- No forced current sharing is required, allowing for simplified winding design
- More compact design with less material and oil, lower weight and smaller dimensions
Advantages for mains operation:
- Low maintenance thanks to vacuum technology
- Improved transmission system resilience and reliability
- Higher transmission capacities
