Method for diagnosing failure of photovoltaic array

Abstract

The invention discloses a method for diagnosing a failure of a photovoltaic array. The photovoltaic array is M*N; each string comprises M battery panels and P voltage sensors, wherein P is less than M / L. When measured values of the voltage sensors in a certain string are not in a preset range, whether the battery panel in the measurement range of the rth voltage sensor fails is judged; if the battery panel in the measurement range of the rth voltage sensor fails, a data acquisition system sends a number corresponding to the failed battery panel to an upper computer; if the battery panel in the measurement range of the rth voltage sensor does not fail, whether the battery panels in the measurement ranges of the rth and (r+1)th voltage sensors fail is judged; if the battery panels in the measurement ranges of the rth and (r+1)th voltage sensors fail, the data acquisition system sends numbers corresponding to the failed battery panels to the upper computer; the upper computer receives the numbers and displays the numbers to an operator; and the operator replaces the battery panels according to the numbers. On the basis of guaranteeing the detection resolution by a special connection mode, the number of sensors is reduced, and the cost of a failure diagnosis system is reduced; and furthermore, the photovoltaic array is detected on line through the data acquisition system and the upper computer.

Description

technical field [0001] The invention relates to the technical field of photovoltaic array fault diagnosis, in particular to a sensor connection method and a fault diagnosis method for photovoltaic array fault diagnosis. Background technique [0002] At present, the fault detection methods of photovoltaic array mainly include infrared image detection method, electrical signal detection method and sensor-based fault diagnosis method. There is a certain temperature difference between the normal working and abnormal working solar panels, and the infrared image detection method uses the temperature characteristics of the measured object to detect [1] . Electrical signal detection method, such as: high-frequency signal injection method [2] The principle is to inject a high-frequency signal into the photovoltaic panel, then detect its reflected signal, and detect and locate the fault of the photovoltaic array according to the different changes of the reflected signal. Based on t...

AI Technical Summary

Problems solved by technology

[0004] The infrared image detection method has the disadvantages of low detection accuracy, high equipment cost, and poor real-time performance; the detection method based on electrical signals also has its own limitations, for example: high-frequency signal injection method for fault detection and positioning of photovoltaic arrays, However, this method is not real-time, and has high requirements for equipment, and the diagnostic accuracy is limited; the sensor-based fault detection method has the disadvantages of using more sensors, low detection accuracy, and the detection structure is difficult to promote in large-scale photovoltaic array applications.

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