Fingrid’s innovation work has resulted in a significant increase in the north-to-south electricity transmission capacity. The technology is known as shunt compensation, and it is a quick, cost-efficient and environmentally friendly way to increase the transmission capacity by hundreds of megawatts. The solution will benefit everyone in Finland, as it enables Finland to remain a single wholesale price area.
The electrification of society is increasing the need for electricity, especially in Southern Finland, while electricity generation is weighted towards the north. In recent years, wind power has accounted for a significantly larger share of the power system production. Wind power generation in Finland is weighted towards Northern Finland, so efficient north-to-south electricity transmission is required.
At present, four strong 400-kilovolt transmission lines pass through cross-section Central Finland in the electricity system of Finland, and the transmission capacity of these lines is now being boosted with the help of shunt compensation. Technically, the electrical power that can be transmitted through cross-section Central Finland is constrained by the quality of the voltage under normal operating conditions at the substations south of the cross-section, as well as variations in the post-fault voltages. The outcome of the development work is that capacitors will be added to the main grid to stabilise the voltage, thereby significantly increasing the transmission capacity through cross-section Central Finland. However, this innovation is no substitute for future power line projects and the need to build new substations.
Further information: www.fingrid.fi/en