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Shunt reactors are the most compact devices, and are normally used to compensate reactive power in long high- and medium-voltage transmission lines for both overhead lines and cable systems. They can be shunt-connected to the electrical line and to the tertiary winding of a three-winding transformer. The shunt reactor is generally connected permanently, but in some cases it can be connected automatically through a switch according to the capacitive power to be compensated on the network.

GBE has extensive experience in producing reactors, not just shunt type but also short circuit limiters for both indoor and outdoor use, neutral forming reactors, low- and medium-voltage filter reactors, smoothing reactors, and detuning reactors.

From among the projects we worked on in 2022, an important one was the supply of a class 36kV 1MVAr single-phase shunt reactor for railways. The reactor was for one of the largest infrastructure builders in Finland, a leader not only in road and bridge construction, but also in underground and railway line actualisation. All the engineering projects for track electrification, safety equipment, and complex structural engineering projects were actualised in-house. The supplied reactor had to satisfy component technical requirements specifically for connection to the railway electrical network. The reactor was supplied complete with conservator, a Buchholz relay, an oil level indicator with two contacts, a thermometer, a thermal image, and remote-controlled current transformers on the secondary side. It was installed outdoors, so both the tank and the radiators were hot dip galvanized and coated with a solvent paint that resists atmospheric agents and extremely low temperatures (-40°C, coating class C4).