DEVICE FOR CONNECTION OF CAPACITORS TO TRACTION AC NETWORK Russian patent published in 2019 - IPC H02J3/18 

FIELD: electrical engineering.

SUBSTANCE: invention relates to electrical engineering, particularly to condenser units with discrete control, designed for transverse compensation of reactive power in traction alternating current networks of electrified railways. Device can perform both three-stage and two-stage control of reactive power. At two-stage control the third stage is in reserve. Three-stage connection of capacitors to AC traction network is performed through circuit with three single-phase bridge rectifiers. Rectifiers are made in the form of three diode branches (three-phase diode bridge) and one common for them diode branch. Through the reactor, the common diode branch is connected to the rail, and the other three are connected to the capacitors of the first, second and third stages, respectively. In direct-current circuit of three matched single-phase diode rectifiers there is a smoothing throttle. Due to natural properties of the device, each stage is smoothly switched on with increasing current and voltage of each capacitor charge by exponential law. After steady-state voltage is achieved on capacitors of each stage, the process of their connection is completed with the help of three contactors which individually shunt input terminals of each rectifier.

EFFECT: proposed technical solution allows reducing the number of elements in the device and improving its reliability; it is more reliable for traction power supply systems and can replace known capacitor plants for two- or three-stage transverse compensation of reactive power in traction alternating-current networks of electrified railways.

1 cl, 3 dwg