Railway power supply system comprehensive electric energy quality treatment device and method thereof

The invention discloses a railway power supply system comprehensive electric energy quality treatment device and method thereof. A static var generator comprises a power unit and an electric reactor and is connected with a pre-charge loop; the power unit is connected in series with the electric reactor; and the pre-charge loop is connected with a power side of a power grid through an AC (alternating current) switch. A thyristor switch electric reactor comprises more than two electric reactor branches; each electric reactor branch comprises an electric reactor and an electronic switch; the electric reactor is connected in series with the electronic switch; and the electric reactor branch is connected in parallel on a load side of the power grid through the electronic switch. A control protection system controls the investment of the electric reactor branches to compensate for the reactive power and controls the static var generator to compensate for the reactive power. The device and method disclosed by the invention overcome the technical shortcomings that the cost is high by using a static var generator only and the thyristor switch electric reactor can not realize continuous compensation, and also consider the advantages of high regulation speed, wide operation range, reactive power compensation and harmonic wave treatment of the static var generator and large capacity and low cost of thyristor switch electric reactor.