Flywheel energy storage voltage sag system for power distribution network and use method thereof

Abstract

The invention provides a flywheel energy storage voltage sag system for a power distribution network, which relates to the technical field of flywheel energy storage of a transformer substation. The flywheel energy storage voltage sag system for the power distribution network comprises a voltage sag detection unit, a voltage sag compensation calculation unit and a flywheel charging and discharging control unit. The invention further discloses a use method of the flywheel energy storage voltage sag system for the power distribution network. The method comprises steps that S1, when flywheel energy storage undertakes a frequency modulation task, k2 is in a closed state, the flywheel energy storage is connected to a 10kV alternating current bus of a transformer substation through a parallel transformer; S2, k1 is in a closed state, k3 is disconnected, and a series transformer does not work, and aiming at the problem that the utilization rate of the DVR is not high, flywheel energy storage is fully utilized, and the flywheel energy storage is used for solving the problem of voltage sag of the power distribution network while cooperating with new energy power generation, so that the influence of the voltage sag of the power distribution network on sensitive users can be solved, and the fee paid by additionally installing a DVR can be avoided.

Description

technical field [0001] The invention relates to the technical field of flywheel energy storage in substations, in particular to a flywheel energy storage system for voltage sag in a distribution network and a method for using the same. Background technique [0002] The flywheel energy storage system is an energy storage method that stores energy in the system in the form of rotational kinetic energy by accelerating the rotor (flywheel) to a very high speed. When releasing energy, according to the principle of energy conservation, the rotation speed of the flywheel will decrease; while storing energy in the system, the rotation speed of the flywheel will increase accordingly. Most FES systems use current to control the speed of the flywheel, while directly using Mechanical energy equipment is also being developed. The rotor used in the high-energy FES system is made of high-strength carbon fiber and is suspended by magnetic bearings. The rotor speed in the vacuum enclosure ca...

AI Technical Summary

Problems solved by technology

[0003] At present, the commonly used method to control voltage sag is to install a dynamic voltage restorer (DVR) at the sensitive load, but the cost of DVR is relatively high. Due to the installation cost and unclear division of installation responsibilities, the utilization rate in China is not high.

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