Distribution network reliability evaluation method suitable for distributed power supply with high permeability

Abstract

The invention discloses a distribution network reliability evaluation method suitable for a distributed power supply with high permeability. The method comprises the following steps of dividing a power supply area of the distributed power supply and obtaining a normal system operation period and a system failure operation period through uniform random number inverse transformation; carrying out power matching in the normal system operation period to obtain failure times and failure time of each load point in the corresponding period; carrying out failure effect analysis to obtain an isolated island operation state of each area and the failure times and the failure time which are generated by the failure effect of the component on the load point according to a relative position of a failurecomponent and each area; carrying out power matching in the system failure operation period to obtain the failure times and the failure time of each load point in the corresponding period according to the isolated island operation state of each area; and simulating for many times to obtain the failure times and the failure time of each load point in the simulative total period and computing a reliability index. According to the method, the distribution network reliability evaluation method under the high permeability condition of the distributed power supply is realized.

Description

technical field [0001] The invention relates to the field of power grid security assessment, in particular to a distribution network reliability assessment method under the condition of high penetration of distributed power sources. Background technique [0002] It is the current energy development trend to install a large number of distributed power sources on the side of the medium-voltage distribution network. It is generally believed in the industry that the penetration rate of distributed power generation is low when the access of distributed power generation will not have a significant impact on the power flow of the connected system. The energy penetration rate is used to define the distributed power penetration rate, which is the ratio of the total power provided by distributed power sources throughout the year to the total power consumption of loads in the power supply area throughout the year. When the energy penetration rate is increased to 30%, the duration of t...

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Problems solved by technology

However, due to the fluctuation of renewable energy output, if the load is mainly powered by renewable energy, whether the reliability of the load's power supply can be guaranteed is an urgent problem to be solved.

[0004] At present, the reliability evaluation of the distribution network containing distributed power mainly focuses on the low penetration rate of distributed power, and does not divide the distribution network according to the power supply area of ​​distributed power: Literature "Liang Huishi, Cheng Lin , Liu Sige. Reliability Assessment of Distribution Network Containing Microgrid Based on Monte Carlo Simulation[J]. Power Grid Technology, 2011,35(10):76-81." The method of calculating the reliability index based on the joint generation model of distributed power generation and energy storage, but it is mainly suitable for the situation where the distributed power generation is less connected and the penetration rate is low; the literature "Ge Shaoyun, Wang Haoming, Wang Yuanshan, etc. contains Distribution System Reliability Evaluation of Distributed Wind-Storage Storage [J]. Electric Power System Automation, 2012, 36(5): 16-23." Disclosed a method that uses non-sequential Monte Carlo simulation to consider the influence of fault partitions to calculate reliability However, its fault feeder partition method is not suitable for regional division when the access penetration rate of distributed power is high, and its distributed power is used as an auxiliary power supply, and only performs power matching and load on the island during the fault period. In the rest of the time, there is no need for power matching because the distribution network is regarded as infinite. Obviously, this analysis method is not suitable for the case of high penetration of distributed generation; so far, for the case of high penetration, there is no Published reports on effective methods for distribution network reliability

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