Distributed power supply island fault detection method

Abstract

The invention discloses an intelligent distributed power supply island detection method based on variational mode decomposition, a Teager energy operator and a one-dimensional convolutional neural network, features of a three-phase PCC point voltage and a converter output current are represented by using the variational mode decomposition, and meanwhile, in order to accurately track the instantaneous change of an intrinsic mode function component IMF1 of a feature signal, a Teager energy operator and a one-dimensional convolutional neural network are provided. A Teager energy operator is introduced to highlight island fault features, a feature vector space formed by Teager energy operator features, intrinsic mode function IMF2 component features and intrinsic mode function IMF3 component features is used as input of a one-dimensional convolutional neural network, and the island fault features can be highlighted under the conditions that disturbance signals are not injected into a system, a threshold value does not need to be set and parameter setting is not carried out. And islanding events and non-islanding events can be quickly and accurately classified and identified.

Description

technical field [0001] The invention relates to the technical field of distributed power island fault detection, in particular to a detection method for distributed power island faults based on an adaptive VMD-Teager energy operator. Background technique [0002] With the integration of distributed power systems and traditional power grids, energy efficiency and reliability have improved, new transmission lines have been reduced, and problems such as line losses have been avoided. The power system has gradually developed towards low carbonization. However, the steady-state and dynamic characteristics of distributed power generation bring technical challenges to control and protection, and pose a potential threat to the reliability of power systems. Island faults are one of the main problems in this context. Island fault refers to the phenomenon that when the power grid stops working due to maintenance or unexpected failure, the distributed power generation system connected t...

AI Technical Summary

Problems solved by technology

The active method judges the island state by introducing a disturbance signal to make the voltage or frequency deviate from the normal value after the island occurs, such as frequency shift method, power disturbance method, impedance measurement method, etc. However, this method will reduce the power quality of distributed power generation

The passive method judges the island based on abnormal voltage or frequency measurement, such as over / undervoltage detection method, over / underfrequency detection method and voltage harmonic detection method. When all are provided by distributed power sources, there is a large detection blind area, and it is difficult to choose an appropriate detection threshold

The remote method achieves detection through signal acquisition and communication technology. The disadvantage of this method is that the detection cost is high and it is difficult to popularize and apply.

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