Hierarchical and domain-based island protection method with anti-stealing function for large-scale wind power

Abstract

The invention discloses a layered and domain-partitioned island protection method with a non-fault-trip preventing function aiming at a large-scale wind power plant. The layered and domain-partitioned island protection method comprises the steps of: starting a non-fault-trip prevention real-time detection module, detecting all circuit breakers in a wind power generation system in real time; monitoring tripping signals of all the circuit breakers arranged in the wind power generation system; judging whether cluster main station sending-out tie lines and main transformers are all cut off through tripping signals of circuit breakers of a cluster main station, and protecting a formed island; judging whether an island is formed due to booster station transformer faults through tripping signals of booster station transformer circuit breakers, and protecting the formed island; judging whether an island is formed due to wind power plant collection bus faults through tripping signals of wind power plant collection bus circuit breakers, and protecting the formed island; and judging whether an island is formed due to wind power plant current collection feeder faults through tripping signals of fan feeder circuit breakers, and protecting the island formed due to the wind power plant current collection feeder faults. The layered and domain-partitioned island protection method achieves the advantages of being fast, accurate, efficient, safe and stable.

Description

technical field [0001] The invention relates to the field of anti-islanding protection for large-scale wind power generation, in particular to a layered and domain-divided island protection method with anti-stealing functions for large-scale wind power generation. Background technique [0002] The island state of a large wind farm (base) refers to the operating state in which some wind turbines in a large wind farm (base) continue to supply power to the loads under them after they are disconnected from the main grid. In large-scale wind power generation systems, effective and timely detection of isolated islands is of great significance to wind turbines and local loads. The principles and situations caused by large-scale wind power access to isolated islands are different from those in the distribution network. Therefore, the harm of large-scale wind power access to isolated islands is also different from the harm of isolated islands in the distribution network. First of al...

AI Technical Summary

Problems solved by technology

2) The unique fault characteristics of the wind turbine. The wind turbine converter generally performs current control. The wind turbine is boosted through a step-by-step transformer. The wind turbine also needs to send electric energy to the booster station through a long collector feeder. In this system There is a large reactance, the system impedance is large, and the electromagnetic environment is relatively complex. Under sudden power failure, a large transient overvoltage will be generated

3) The island system is an unstable system, and its damping is small, which will generate a large transient overvoltage

4) If the system is not powered off at the beginning of reclosing, there will be an impulse voltage, and the more serious situation is that non-synchronous reclosing occurs. At this time, a large transient overvoltage will appear

Disadvantages of this method: additional equipment is required, high implementation cost, complex operation, many certifications are required, and low economy

This method needs to consider the weight of the line, so there is a problem of large delay in the action of anti-islanding protection

Images