Novel photovoltaic group string online fault diagnosis system and method in integrated inverter scheme

Abstract

The invention discloses a novel photovoltaic group string online fault diagnosis system in an integrated inverter scheme. The system comprises a collection module, a storage module and an analysis module, wherein the analysis module comprises a basic constraint analysis module, a current deviation analysis module, a threshold value analysis module and a voltage-current deviation consistency analysis module. The invention also discloses a novel photovoltaic group string online fault diagnosis system in the integrated inverter scheme. The method comprises the following steps: collecting the operating data of each group string; judging whether the operating data meet basic constraint conditions or not; carrying out analysis on the current deviation of each group string; judging whether the operating data of each group string reach preset threshold values or not; analyzing voltage-current deviation consistency and judging group string faults. The method has higher sensitivity and lower false alarm rate for voltage type faults occupying more than 90% of photovoltaic module faults, and the diagnosis result is stable and reliable; the method is simple to implement, small in one-time analysis range, short in inspection cycle, few in occupied resources, low in hardware requirement and convenient for large-scale popularization.

Description

technical field [0001] The invention relates to a photovoltaic string fault diagnosis system and method, in particular to a novel photovoltaic string online fault diagnosis system and method for a centralized inverter scheme. Background technique [0002] At present and even in the future, my country's photovoltaic power generation will maintain a high-speed development state. In contrast, photovoltaic power generation technology is still in its infancy, and the professional skills of power station personnel are low, coupled with the lack of assistance from intelligent production and operation systems, resulting in a generally low level of operation and maintenance. economic losses and safety hazards. [0003] The low energy density of photovoltaic power generation, the large number of equipment, and the increasingly stringent cost constraints make it difficult for the power station monitoring system to accurately and comprehensively monitor the operating status of the basi...

AI Technical Summary

Problems solved by technology

[0007] The technical problem to be solved by the present invention is that the fault diagnosis of power station components in the prior art is difficult, there are many false alarms and false alarms, and the technical problems are not strong in practical performance. More than 90% of serious component failures are voltage-type faults, and an efficient short-period fault diagnosis method with a cycle of minutes is proposed, using the transient process of the system dynamic adjustment during the maximum power tracking process of the inverter, or the system power limit For special working conditions, hidden faults are found

Images