An Active Distribution Network Protection Scheme Considering Regional Measuring Capabilities

Abstract

The invention discloses an active distribution network protection scheme taking the regional measurement capability into account, which comprises the steps of (1) building a fault characteristic analysis model of an inverted distributed power supply under a constant power control mode; (2) analyzing fault characteristics of the distributed power supply under a fault condition and influences imposed on current protection of a distribution network; (3) constructing an active distribution network protection system architecture, and completing the positioning for a fault line according to the fault current direction at a circuit breaker; and (4) using grid connection of the distribution power supply and an active distribution network re-closing scheme coordinated with the time sequence of theoperation time of distribution network protection. The active distribution network protection scheme can eliminate influences imposed on distribution network protection by DG access, removes influences imposed on the protection scheme by load current by using the current fault component as a characteristic electrical quantity at the same time, and has high reliability. The re-closing scheme does not change the original protection configuration of the distribution network, does not rely on a communication network and has very high economic advantages and engineering practicability.

Description

[0001] Field [0002] The invention belongs to the technical field of distribution network protection, and in particular relates to an active distribution network protection scheme considering regional measurement capabilities. Background technique [0003] The concept of distributed power generation was born in the 1980s, which refers to the power supply with small capacity introduced near the user side in the power distribution system. With the maturity of small-scale power generation technologies such as solar energy and wind energy, more and more solutions use scattered resources to meet the needs of small-scale users. [0004] The overall development of distributed power in my country is not behind, but limited by resource conditions, policy standards and differences in technology types, the development of photovoltaic power generation, cogeneration and other fields is still in its infancy and the scale is small. Although the installed capacity of wind power has increase...

AI Technical Summary

Problems solved by technology

After the distributed power supply is connected, the unidirectional power flow characteristics of the distribution network become bidirectional power flow characteristics, the premise of traditional protection setting coordination no longer exists, and the traditional three-stage current protection is no longer effective

At the same time, the structure of the distribution network is complex, there are many branches, and the measurement capability of some distribution network areas is limited, and the engineering practicability of the existing protection schemes is not strong

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