Loop closing power supply operation risk assessment method for power distribution network

Abstract

The invention discloses a loop closing power supply operation risk assessment method for a power distribution network. The method comprises the steps of 1: analyzing the type of a loop closing mode; 2: properly adjusting values and power factors of loads on two sides of a loop closing point; 3: ensuring a sum of the loads on the two sides of the loop closing point not to exceed a rated load of oneof switches on the two sides; 4: according to a superposition theorem, calculating line power flow after loop closing, and calculating a phase difference and a voltage of the two sides of the loop closing point; and 5: calculating a loop closing impact current and a loop closing steady-state current, performing safety check on all devices on the loop by utilizing the loop closing impact current and the loop closing steady-state current, and judging whether the loop closing can be performed or not. According to the method, the power supply reliability can be improved; better services can be provided for users; the power supply reliability of the power distribution network can be enhanced; the power supply flexibility of the power distribution network is ensured; the economy of power distribution network operation is improved; and remarkable social and economic benefits are achieved.

Description

technical field [0001] The invention relates to the field of risk analysis in electric power systems, in particular to a risk assessment method for distribution network closed loop power supply operation. Background technique [0002] With the development of society and economy, users' requirements for power supply reliability and power quality are also increasing. Dual power supply and multi-power supply have become effective power supply modes to improve the reliability of distribution network power supply. In this mode, the distribution network generally adopts the power supply mode of "closed-loop design, open-loop operation". Ensure the reliability and flexibility of the power supply of the distribution network, improve the economy of the distribution network operation, and reduce the impact on users. Closed ring power supply is imperative! [0003] However, during the loop closing operation, due to the voltage difference between the two sides of the loop closing swit...

AI Technical Summary

Problems solved by technology

[0003] However, during the loop closing operation, due to the voltage difference between the two sides of the loop closing switch, the phase angle difference, the complex operating parameters of the distribution line, and the unpredictability of the adjustment of the main network operation mode, etc., it may cause the loop in the non-stop power transfer operation. Excessive circulating current causes misoperation of overcurrent protection of distribution lines, which in turn leads to power supply accidents

The technical analysis methods mastered by dispatchers are also very limited. When performing non-stop power transfer operations, they can only rely on past experience to judge whether to close the loop. Quantitative analysis, without systematic theoretical calculation schemes and evaluation standards, the results of actual operations are very random, and there are certain operational risks

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