Power distribution network fault recovery method based on active control of distributed power supply

Abstract

The invention provides a power distribution network fault recovery method based on active control of a distributed power supply. The method comprises the following steps: firstly, acquiring parameters such as voltage amplitude and phase angle, active load, reactive load, initial active power output, initial reactive power output and initial switch state of each node of a power distribution network in real time by using terminal equipment; when the power distribution network has a fault, disconnecting the adjacent switch of the fault section to isolate the fault, calculating a new state combination of the section switch and the interconnection switch by using the operating parameters at the moment, and further formulating a switching-on and switching-off operation sequence scheme; before the interconnection switch closing operation is executed each time, the distributed power supply optimal control point at the upstream of the loop closing point is calculated according to the preset closing time; and adjusting the power control reference value of each distributed power supply, and then carrying out switching-on operation. The method is easy to implement, loop closing voltage fluctuation in the power distribution network fault recovery process can be restrained to the maximum extent, and the safety and reliability of a new energy power system are effectively improved.

Description

technical field [0001] The invention relates to the technical field of new energy power generation control, in particular to a distribution network fault recovery method based on active control of distributed power sources. Background technique [0002] Fault recovery refers to the process of recovering the lost load to the maximum extent under the premise of ensuring system safety through a series of means after the grid fails and is isolated. Network reconfiguration is the main means of fault recovery in radial distribution network. However, due to the constraints of branch capacity and node voltage, network reconfiguration often faces the problem of node voltage fluctuation or even exceeding the limit. With the increasingly serious global energy crisis and environmental pollution problems, the proportion of wind power, photovoltaic and other distributed power sources connected to the distribution network is increasing year by year, making the traditional distribution net...

AI Technical Summary

Problems solved by technology

However, if the voltage difference between the nodes on both sides of the tie switch is large, a large circulating current will be generated in the electromagnetic ring network after the ring is closed, and the impact current generated at the moment of the ring closure may cause equipment overload and affect the correct operation of the protection

Under the influence of the constant outlet voltage of the distribution network substation, the impact component in the closing loop current is transmitted to the downstream feeder, which causes the voltage of each node to fluctuate or even exceed the limit

Most of the existing methods only check the steady-state safety of the switch state, and a few literatures consider the steady-state and transient safety constraints of the loop closing operation during the reconstruction process, but they all focus on ensuring that the loop closing current does not exceed the limit, which is relatively Pay less attention to the voltage problem in the ring closing process, and lack the means of active suppression

[0004] The current common practice is to introduce reactors or energy storage equipment, and give priority to disassembling distributed power sources with large capacity, unadvanced excitation control, or close to the loop closing point when closing and unlinking operations, but it also weakens the impact of distributed power sources on power distribution. The supporting role of the distribution network is not conducive to the fault recovery of the distribution network

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