The reactor used in the electric power system is a series reactor and a parallel reactor. The series reactor is mainly used to limit the short circuit current, and also in the filter with the capacitor in series or parallel to limit the high order harmonics in the power grid. The reactor in the power grid of 220kV, 110kV, 35kV and 10kV is used to absorb the charge and capacitive reactive power of the cable lines. The operating voltage can be adjusted by adjusting the number of shunt reactors.
The EHV shunt reactor has many functions to improve the reactive power of the power system, including: (1) capacitive effect on light and no load or light load lines, so as to reduce power frequency transient overvoltages. (2) to improve the voltage distribution on the long transmission line. (3) the reactive power of the line in the light load is balanced as much as possible to prevent the irrational flow of reactive power, and the power loss on the line is also reduced. (4) when the large unit and the system are parallel, the power frequency steady voltage on the high voltage bus is reduced so as to facilitate the synchronous generator in the same period. (5) to prevent the self excitation resonance generator with long lines possible. (6) when the reactor neutral point is connected with a small reactance grounding device, a small reactor can also be used to compensate the phase to phase capacitance between the lines, so as to accelerate the automatic extinguishing of the secondary supply current and facilitate the adoption.