Anti-islanding protection system and method

Abstract

The invention discloses an anti-islanding protection system and a method. The system comprises a substation area island detection device, a wireless communication system and an anti-islanding protection device, and is characterized in that the substation area island detection device is used for acquiring the position of each circuit breaker inside a substation, detecting whether a public power grid losses power and forms an island or not in real time, and sending a message to the anti-islanding protection device through a wireless communication system; and the anti-islanding protection device receives the communication message sent by the substation area island detection device through transmission of the wireless communication system, acquires voltage and frequency at a point of common coupling of a distributed power station, and controls a circuit breaker of the point of common coupling to trip when any one of the following conditions is met: 1) a wireless cascading trip message is received; 2) wireless communication is normal, and a low / over frequency and low / over voltage insensitive section criterion is satisfied; and 3) wireless communication is abnormal, and a low / over frequency and low / over voltage sensitive section criterion is satisfied. The invention has the characteristics that the economy of the anti-islanding protection system is improved, and the sensitivity and the reliability of anti-islanding protection are improved.

Description

technical field [0001] The invention relates to an anti-islanding protection system and method, and belongs to the technical field of distributed power generation. Background technique [0002] The island effect is an important problem in the grid-connection of distributed power generation. The so-called island effect means that when the power company jumps due to power supply failure or outage maintenance, the grid-connected power generation system at each user end and the surrounding load form a power company that cannot Self-powered islands under control. This self-sufficient island phenomenon will have serious consequences for maintenance personnel, electrical equipment, and even the power grid. Therefore, the distributed generation system must be able to detect the occurrence of the island effect in a timely manner. In order to quickly and accurately detect the islanding effect, the power company generally requires an anti-islanding protection device to be installed at...

AI Technical Summary

Problems solved by technology

The active principle generally needs to apply a disturbance signal to the power grid, which is complicated to implement and affects the power quality, so it is rarely used in relay protection devices; The advantage is that the principle is simple and easy to implement, but the detection has a certain blind spot; it is the most direct method for island detection, and it has the characteristics of high sensitivity and quick action by detecting the position of the switch in real time to determine whether the grid-connected system has islands. , but the use of optical fiber communication requires the laying of optical fibers, which is easily constrained by economy and inconvenient construction, and it is difficult to implement in many occasions

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