Electricity and Control December 2022

TRANSFORMERS, SUBSTATIONS + CABLES : PRODUCTS + SERVICES

Substations are critical in grid stabilisation

The increasing demand for electricity, the phasing out of coal and to some extent nuclear power, and the necessary expansion of renewable energies pose major challenges to the energy system. Typically, the backbone of the energy supply system is the extra-high voltage grid, and in Bavaria, Germany, this enables the transport of renewable energies from north to south as well as the integration of regionally generated green electricity. The linchpins are transformer substations that link the transmission network – the highways, so to speak – with the subordinate distribution networks – that is, the rural and urban roads. Together with power lines, substations are a key factor in the success of the energy transition and, in this instance, in ensuring that Germany and Bavaria remain strong industrial locations with reasonable energy costs. The Schwandorf substation is the supply centre for the Upper Palatinate region and is currently being modernised during ongoing operations to make it fit for the energy transition. Leading European grid operator, TenneT, is investing a total of around €68 million in the Schwandorf substation, including €2.5 million in a new MSCDN system from Maschinenfabrik Reinhausen (MR) in Regensburg. The main task of the plants is to provide static reactive power, which is used in stages for reactive-power control and voltage control. At the same time, the systems can im prove the voltage quality and dampen resonances in the grid. The plants have many advantages, such as low loss es, economic efficiency and high availability. This so-called reactive power must be available in a sta ble and uniform way, as was previously provided by fossil fuel power plants. With the phase-out of coal and nuclear power, these rotating generators are gradually becoming fewer and, due to the increasing feed-in of renewable ener gies, the voltage in the power grid is subject to ever-great

TenneT Germany and MR recently symbolically commissioned the new MSCDN plant. er fluctuations that have to be absorbed by the transmis sion system operators. in an ac voltage network, current can only flow with the right ratio of active to reactive power. It is needed to build up and dissipate a magnetic field 50 times per second and thus to maintain the voltage during current transmission. If there is too much reactive power in the network, less active power is transported; if there is too little reactive power, the voltage drops and power supply disturbances can occur. With the MSCDN system, TenneT can absorb the voltage fluctuations in the substation effectively and thus stabilise the operation of the transmission grid. In early October 2022, Tim Meyerjürgens, Managing Director of TenneT Germany, andWilfried Breuer, Managing Director of Maschinenfabrik Reinhausen, symbolically commissioned the new MSCDN plant. Tim Meyerjürgens said, “Every milestone reached and every partial commissioning helps us to achieve the ambitious climate policy goals of Bavaria, to integrate more renewables

The Schwandorf substation is a key regional supply node.

30 Electricity + Control DECEMBER 2022