Photovoltaic fault detection characteristic quantity extraction method

Abstract

The invention relates to the technical field of photovoltaic fault detection, discloses a photovoltaic fault detection characteristic quantity extraction method, and provides an MPPT (maximum power point tracking) maximum power point and equivalent resistance Rs, open-circuit voltage Voc, maximum power point current Im and maximum power point voltage Vm which are extracted on the basis of a trust region affine algorithm in combination with an optimization observation perturbation algorithm and an optimization conductance increment algorithm. According to the method, the defects of the perturbation algorithm are overcome through an incremental conductance method, and results obtained through two kinds of detection are comprehensively considered to determine the maximum power point, so that the accuracy of the algorithm is improved. The method comprises the following steps: extracting characteristic parameters of an I-V curve by using a trust region affine algorithm, calculating each characteristic quantity, comprehensively judging a photovoltaic array fault, and combining the characteristic quantity with MPPT (Maximum Power Point Tracking) to detect whether data is wrong or not so as to achieve high-precision detection.

Description

technical field [0001] The invention relates to a method for extracting characteristic quantities of photovoltaic fault detection, belonging to the technical field of photovoltaic fault detection. Background technique [0002] With the vigorous development of solar photovoltaic applications, the construction cost of photovoltaic systems has gradually decreased, and the installed capacity and quantity have continued to increase, resulting in continuous increase in operation and maintenance costs. Since the photovoltaic system needs to be installed in an outdoor environment with many uncertain factors, it is easily affected by various environmental factors such as thermal cycle, humidity, ultraviolet rays, and shadows during operation, resulting in local material aging, cracks, hot spots, short circuits, Various faults such as open circuit or shading will reduce the power generation efficiency of the photovoltaic system, and even damage the equipment in serious faults, causing...

AI Technical Summary

Problems solved by technology

[0003] At present, the fault detection methods of photovoltaic arrays mainly include infrared image detection method, electrical signal detection method and sensor-based fault detection method. maintenance, which may result in economic loss

However, some other detection methods may require a large amount of equipment investment, are not easy to replace when damaged, and have low detection accuracy.

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