JPS6295611A - Sun tracking device - Google Patents

Abstract

PURPOSE:To prevent the malfunctions of a sun tracking device despite the change of intensity of the incident light, by using an optical sensor for incident light. CONSTITUTION:The 3rd optical sensor 4C is provided for detection of the intensity of the incident light L in addition to optical sensors 4A and 4B which detect the direction of the light L. The signal detected by the sensor 4C is used as the comparison input for both comparators 6A and 6B for detection of the shift via an amplifier 5C and a ratio setter 9. Therefore the comparison input changes in the same rate as the changing rate of the intensity of the light L. Thus it is possible to always detect the shift in the same state. While a comparator 6C compares the output of the sensor 4C with the signal of the reference value set by a setter 10. Then the drive of a motor 3 is stopped via a motor controller 8 in case the intensity of the light L is less than a prescribed level.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application] The present invention relates to a solar tracking device that is necessary when sunlight is collected and used by an optical system.

[Conventional technology]

Devices that condense and utilize sunlight include concentrating heat collecting devices for obtaining high-temperature heat, concentrating photovoltaic devices, and the like. These devices use optical systems such as curved mirrors and lenses to collect sunlight.

Therefore, a sun tracking device is required to match the direction of incidence of the moving sunlight with the optical axis of the optical system.

FIG. 2 is a configuration diagram showing an example of a conventional solar tracking device used in a concentrating type heat collector. In this figure, 1 is a reflecting mirror, 2 is a heat collector, 3 is a motor, and 4A.

4B is the first of the pair. The second optical sensor, 5A and 5B are amplifiers, and the first optical sensor is 6A and 6B. Second comparator, 7 is setter, 8
is the motor controller, and L is the incident light from the sun.

The incident light Lres is reflected by the reflecting mirror 1 and is transmitted to the heat collector 2 and the sensor 4.
The signals detected by A and 4B are sent to amplifiers 5A and 5B.
After each 1st. It is input to second comparators 6A and 6B.

On the other hand, a setting device 7 that sets and transmits the standard of the intensity of incident light.
The reference signal from the first . The output signals of the second optical sensors 4A, 4B and the signal from the setting device 7 are compared in magnitude, and the output signals are inputted to the motor controller 8, which controls the motor 3 in feedback mode so that the reflector 1 is always correctly focused. It is maintained in a state of light.

[Problem that the invention seeks to solve]

In the conventional solar tracking device as described above, when the intensity of incident light changes due to changes in the weather, each optical sensor 4A, 4
The intensity of the incident light incident on B also changes, and the comparators 6A and 8B
The signal input to the device also changes.

On the other hand, since the reference value output from the setting device 7 is constant, the sensitivity for detecting deviations in reflected light changes, making it difficult to maintain the correct focusing position at all times, and in severe cases, malfunctions may occur. There were some problems.

This invention was made to solve the above-mentioned problems, and it is an object of the present invention to provide a sun tracking device that does not malfunction even when the intensity of incident light changes.

[Means for solving problems]

The sun tracking device according to the present invention includes a third optical sensor that detects the intensity of incident light, and outputs a signal proportional to the output of the third optical sensor to the first. A third optical sensor is provided to detect the intensity of the second comparator, and a third comparator is provided to stop the feedback control when the intensity of the incident light becomes less than a predetermined value. .

[Effect]

In this invention, the third optical sensor detects the intensity of incident sunlight, and sends a signal proportional to the detection signal of the third optical sensor to the first optical sensor. A deviation is detected by comparing it with the level of the second optical sensor. Also, if the incident light falls below a predetermined value, the third
The comparator detects this and stops feedback control.

〔Example〕

FIG. 1 is a configuration diagram showing an embodiment of the present invention, in which the same reference numerals as in FIG. 2 indicate the same parts, 4C is a third optical sensor, 5
C is an amplifier, 6C is a comparator, 9 is a third optical sensor, 10
is a setter.

In the embodiment shown in FIG. 1, in addition to the configuration of the conventional example shown in FIG. The first.
If the incident light becomes weaker by using the comparison inputs of the second comparators 6A and 8B, the comparison inputs also become weaker at the same rate, so that deviations can always be detected in the same state. Also, by comparing the output of the third optical sensor 4C that detects the incident light [4] with the reference value signal set by the setting device 10 by the third comparator 6C, it is determined that the incident light has become weaker than the predetermined value. In such a case, the drive of the motor 3 is stopped via the motor controller 8 to prevent malfunction when the incident light becomes extremely weak.

〔Effect of the invention〕

As described above, the present invention provides a third optical sensor that detects the intensity of incident light, and transmits a signal proportional to the output of the third optical sensor to the first optical sensor. In addition to providing a third optical sensor that detects the intensity of the second comparator, we also provided a third comparator that stops feedback control when the intensity of the incident light falls below a certain value. Accurate tracking is always possible even when the intensity of light changes. In addition, since feedback control is stopped when the incident light falls below a certain value, it is possible to prevent 7J4 operation when the incident light becomes extremely weak, resulting in a highly reliable solar tracking device. has advantages.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a block diagram showing an example of a conventional sun tracking device. In the figure, 1 is a reflector, 2 is a heat collector, 3 is a motor, dA, 4
B, 4G are optical sensors, 5A, 5B, 5G are amplifiers, 6A
, 6B, 6C are comparators, 8 is a motor controller, 9 is a third optical sensor, and 10 is a setting device.

Claims (1)

[Scope of Claims] First and second optical sensors are provided at both ends of a heat collector on which incident light from the optical system is focused, and the difference between the output signals of these optical sensors and a reference signal is determined by the first optical sensor. , in a solar tracking device that detects the intensity of the incident light with a second comparator and feedback-controls the optical system based on the difference between the two, a third optical sensor that detects the intensity of the incident light is provided, and the third optical sensor detects the intensity of the incident light. A signal proportional to the output of the sensor is sent to the first
, a ratio setter is provided which serves as a reference signal for the second comparator, and further a third comparator is provided which detects that the output of the third optical sensor becomes equal to or less than a predetermined value and stops the feedback control. A solar tracking device characterized by: