SU1429102A1 - Photodetector for solar-energy units - Google Patents

Abstract

The invention relates to solar technology and can be applied to control devices for solar power plants in solar power plants. The aim of the invention is to expand the range of operating modes of the photosensor. The goal is achieved due to the fact that the additional photodetector is installed on the vertical axis of the four-quadrant photodetector at a distance from its center equal to the distance between the photoelectric elements opposite to the center, and by organizing the logical processing of the output signals of all photoelectric cells using the additionally introduced three elements 2I- OR NO. In this case, the photosensor allows defocusing of the solar spot on the steam generator boiler without attracting additional computer aids. 1 silt § (L

Description

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i The invention relates to solar technology and can be applied in the CTJBcix solar control unit for solar power plants.

; The aim of the invention is the rubbing of the range of modes of photosensors.

The drawing shows a functional Hc-jiH photo sensor circuit.

I The photo sensor contains an optical unit 1, a four-quadrant photodetector 2, the first, second, third, fourth, fifth, and fifth. the sixth photocells 3-8, the third, the second and the first differential amplifiers 9-11, the third, the second and the first relay elements 12-14, the 15J inverter the third, the second and the first elements 2I-ШШ-НЕ 16-18, the element OR NOT 19 and the electrical input 20. I Photo sensor operates as follows. When focusing the light spot in the center of the four-quadrant photoreceiver 2, the first, second, third and fourth photocells 3-6 are illuminated in the same way, five photocell 7 are illuminated completely, and the sixth photocell 8 is illuminated only by the background surrounding the radiation source (i.e., the sun) . Thus, the differences in output from the signals of the first and third photocells 3 and 5 and the second and fourth photocells A and 6 are zero, and the difference between the output signals of the fifth and sixth photoelectric cells 7 and 8 is equal to the difference between the light fluxes of the radiation source and the background. When the direction of the optical rays is changed due to, for example, movement of the radiation source, the light spot shifts in any direction. In this case, one pair of photocells, for example, the first and third photocells 3 and 5 (or both pairs of photocells, i.e., the first and third photocells 3 and 5 and the second and fourth photocells 4 and 6) turn out to be lit unequally. The signal intensity of the light flux through the third differential amplifier 9 and the difference signals through the second and first differential amplifiers 10 and P are fed to the inputs of the third, second and first relay elements 12-14. The settings of the operation of the third, second, and first relay elements 12-14 are developed from the condition of the required sensitivity of the photo sensor to the intensity

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luminous flux and the required accuracy of the registration of the displacement of the light spot. In the normal tracking mode, to the input of the photosensor 20, the defocusing signal is given, so the output of the second relay signal is passed to the outputs of the third and second elements 2-OR-NOT 16 and 17. element 13, which depends on the matching of the matching between the output signals of the first and third photocells 3 and 5, and at the output of the first element

18, an intensity signal from the output of the third element 12 will be present, which depends on the difference between the output signals of the fifth and the third photocells 7 and B. The output signals of the first relay element 14 and the third and second elements 2I-1 of SHIENA 16 and 17 arrive at the outputs of the photosensor and to the inputs of the element OR NOT 19o The presence of a logical signal 1 on any of the inputs of the element OR NOT

19 shows that the first, second, third and fourth photocells 3-6 are illuminated and the intensity of the radiation is higher than the background intensity and, therefore, the photosensor is in tracking mode. By changing the direction of the rays by an angle exceeding the angle of capture of the photosensor, or by the appearance between the radiation source and the optical unit 1

 an object preventing the passage of the rays, the illumination of all six photocells 3 - 8; turns out to be the same and the same intensity of the background illumination. At the same time, at the output of the element OR-NOT 19, a logical signal 1 is set, which is a signal of the Tracking mode loss,

When a low potential is applied to the input of the 20 photosensor, the low potential at the outputs of the third and second elements 2-OR-NOT 16 and G / appears signals indicating the presence of a mismatch in the method with the output signals of the fifth and sixth photo cells 7 and B, and at the output of the first element 2I-OR-NOT 18 a radiation intensity signal appears indicating the difference between the light fluxes incident on the first and third photoelements 3 and 5. Under the action of this signal, the control system turns the heliostat to the position at which the fifth and the sixth photocells 7 and B will be lit

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equally, the first photocell 3 will be fully illuminated, and the third photocell 5 will be illuminated by the background (the position of the light spot in this case is shown in the drawing by a dotted line). In the defocus mode, the output signal of the photosensor is monitored by the output signals of the first pair of photosensors 4 and 6 and the second pair of photosensors 7 and 8. Since the photoelectric axis of the photodetector, consisting of the second fourth, fifth and sixth photoelectric cells 4,6, 7 and 8, is offset relative to the photoelectric axis of the photodetector, consisting of the first, third, second, and fourth photovoltaic cells 3-6, then there is a spatial shift in the direction of the solar rays reflected from the heliostat, i.e. defocusing.

The photo sensor allows simultaneous recording of the offset of the light spot relative to the photoelectric axis of the photo sensor to defocus the solar system without using sophisticated computing technology by applying a high or low level signal to the input 20 of the photo sensor Defocusing.

Claims (1)

Invention Formula A photosensor for solar installations, containing an inverter, an optical unit with a four-quadrant photodetector in focus, on the vertical and horizontal axes of which four photo cells are located symmetrically to its center, and in the center is a five photoelectric element, the first outflows opposite to the photoelectric center are connected in pairs to the inputs of the first and second differential amplifiers, respectively. first exit n then 29102 0 five 0 five 0 five 0 five the central photocell is connected to the direct input of the third differential amplifier; the second outputs of the first, second, third, fourth and fifth photocells are connected to the common bus; the outputs of the first, second and third differential amplifiers are connected to the inputs of the first, second and third relays elements, the first and second outputs of the first relay element are connected to the first and second inputs of an OR-HP element; characterized in that, in order to expand the range of operating modes of the photosensor, it Three elements of the 2I-OR-NOT and a sixth photocell are installed, which is mounted on the vertical axis of the four-quadrant photodetector at a distance from its center equal to the distance between the photoelectric elements opposite to the center, the first output of the sixth photocell is connected to the inverse input of the third differential amplifier, and the second - with a common bus, the electrical input of the photo-sensor is connected to the first inputs of the first, second and third elements 2I-OR-NOT and to the input of the inverter connected by the output to the third inputs The first, second and third elements 2I-OR-NOT, the first output of the second relay element is connected to the second input of the second element 2I-OR-NOT, and the second output to the fourth input of the first element 2I-OR-NOT and to the second input of the third element 2I-OR-NOT, the first output of the third relay element is connected to the second input of the first element 2I-PI-NOT and to the fourth input of the second element 2I-OR-NO, and the second input to the fourth input of the third element 2I-OR-NO, the outputs of the first, second and third elements 2I-OR-NOT connected to the fourth, third and fifth input NOR element. U § one nil