A Device and Method for Realizing Sunlight Tracking Using Rod Image

Abstract

The invention belongs to the technical field of solar photovoltaic power generation and particularly relates to a device and method for achieving sunlight tracking through a bar shadow image. The shadow image of a tapered bar is collected through a CMOS camera and is subjected to denoising and graying treatment, and shadow areas of zones A, B, C and D and the average brightness of non-shadow zones are worked out; whether the day is clear or not is judged according to the average brightness of the non-shadow zones; under the clear-day mode, signals are sent to a system azimuth angle motor and a height angle electric push rod according to the area corresponding to the largest shadow area to make a tracking system rotate correspondingly, and the direct solar radiation direction is kept perpendicular to the direction of an incidence tracking device all the time. By means of the device and method, the clear-day or cloudy-day mode can be automatically recognized, the control precision is high, the detection angle is large, a photovoltaic array can be kept tracking direct solar radiation continuously, and power generation efficiency is improved.

Description

technical field [0001] The invention belongs to the technical field of solar photovoltaic power generation, and in particular relates to a device and method for realizing sunlight tracking by using rod shadow images, and is especially suitable for precise tracking of direct sunlight radiation by concentrated photovoltaic systems. Background technique [0002] The motion control of the sun tracking system is the key to the sun tracking technology. At present, the sun tracking motion control methods mainly include the apparent sun trajectory motion control (that is, the program control) and the photoelectric sensor tracking motion control. To achieve precise tracking of the sun, the ideal motion control method should be continuous tracking of the sun's trajectory. [0003] According to the tracking method, the sun tracker mainly includes sensor tracking, calculation of the sun's trajectory tracking and hybrid tracking. The sensor tracking method uses a photoelectric sensor to...

AI Technical Summary

Problems solved by technology

[0004] Four-quadrant photoresistors (or silicon photocells) are commonly used in sensor tracking methods. There are two main problems in the dual-axis tracking sensor: First, the error of photoresistors (or silicon photocells) is relatively large, and multiple photoresistors with completely equal parameters should be selected. Difficulty; Second, this type of sensor cannot identify cloudy or cloudy weather conditions with high average light intensity. When encountering such weather conditions, the system will constantly search for the maximum light intensity

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