JP2587049B2 - Dimming method for tunnel lighting device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dimming method for a tunnel lighting device using solar power as a power source.

[Prior Art] FIG. 2 is a dimming characteristic diagram showing a dimming characteristic in a conventional dimming method of a tunnel lighting device disclosed in, for example, Japanese Patent Application Laid-Open No. 61-250995, and FIG. It is a dimming characteristic diagram in the case of a bad day, in which (1) and (1a) are output characteristics of the power generated by the solar cell, (2) and (2a), respectively.
Is a dimming characteristic in which the amount of electric power changes as the number of lighting fixtures is switched. The horizontal axis indicates time, and the vertical axis indicates electric energy. Generally, the lighting in the tunnel must be brightly illuminated until the human eyes passing through the tunnel adapt to the brightness inside it, that is, over a section from the entrance. It is said that the brightness at this time is ideally approximately proportional to the brightness at the entrance of the tunnel. Therefore, when solar power is used as a power source for lighting in the tunnel, the power generated by the solar cell (hereinafter simply referred to as output) is related to the intensity of sunlight and closely related to the brightness at the entrance of the tunnel. Therefore, it was considered that the brightness in the tunnel should be adjusted, that is, light control was performed by the output of the solar cell.

The conventional dimming method is performed as follows based on the above points. That is, the lighting number of the lighting fixture in the tunnel is adjusted according to the output of the solar cell, and the brightness in the tunnel is dimmed stepwise. For example, as shown in FIG. 2, dimming is performed stepwise with a certain time delay according to a change in the output characteristics of the solar cell. FIG. 3 shows processing performed on a day when the weather is not good. The output characteristic (1a) of the solar cell increases from the morning sunrise, reaches a maximum at noon, and gradually decreases as the sun sets. In addition, the output suddenly drops when clouds come, and the output remains low all day on rainy days. The dimming characteristic (2a) is the second
In the same manner as in the figure, the dimming is slightly delayed from the output characteristic (1a). FIG. 2 shows the characteristics of a day when the weather is relatively good in the morning and tends to be cloudy in the afternoon, and FIG. 3 shows the characteristics of an example of a cloudy or rainy day.

[Problems to be Solved by the Invention] In the conventional dimming method as described above, since the illumination in the tunnel is dimmed according to the output of the solar cell, the tunnel entrance is provided in the north-south direction. However, when the tunnel entrance is in the east-west direction, the brightness at the tunnel entrance is high even when the output of the solar cell is low, especially at sunrise or sunset in the morning and evening. The problem is that the light is dimmed in spite of the high brightness at the entrance of the tunnel, and more specifically, for example, when a car goes to the entrance of the tunnel, the driver in it feels the brightness. This is because reflected light from objects around the tunnel enters the eyes, and this intensity is closely related to the intensity of the sun's rays, and solar cells usually produce the maximum amount of power per day. Usually, it is installed facing south. However, one entrance or the other entrance of the tunnel is not necessarily provided facing south, for example, if it is located in the east-west direction, the sun rays will enter from the east in the morning and from the west in the evening. However, the normal component of the arriving light is very small (because the angle of incidence of the sunlight on the light receiving surface of the solar cell is small), and the output of the solar cell is strong despite the strong sunlight. It will be very small. Therefore, when dimming is performed so that the brightness becomes proportional to the output of the solar cell, the brightness at the entrance of the tunnel during the morning and evening when the output of the solar cell decreases (even if the output of the solar cell decreases due to diffuse reflection or the like, does not decrease much). On the other hand, the illumination in the tunnel is dimmed, and this tendency is particularly remarkable when the tunnel entrance is in the east-west direction as described above.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and provides a dimming method of a tunnel dimmer for dimming the inside of a tunnel to a brightness corresponding to the brightness of a tunnel entrance. The purpose is to:

[Means for Solving the Problems] The dimming method of the tunnel lighting device according to the present invention adjusts the number of lighting of the lighting fixtures in the tunnel while giving a certain time delay according to the change in the output characteristics of the solar cell. In the dimming method for a tunnel lighting device that gradually dims the brightness in a tunnel, the time until the output of the solar cell gradually increases from zero and a predetermined output is obtained over the past several days. Set the average of as the sunrise time zone,
Over the past several days, the output of the solar cell gradually falls from a predetermined output and set a little before the average value of the time until it reaches zero, as a sunset time zone, the sunrise time zone and the sunset time zone An output larger than the actual output of the solar cell is supplied from the charging battery to the illumination lamp at the entrance of the tunnel.

[Operation] In the present invention, the time zone of the sunrise or sunset is stored, so that the dimming is made stronger in these time zones than in the output of the solar cell.

[Embodiment] FIG. 1 is an explanatory diagram for explaining a dimming method according to an embodiment of the present invention. FIG. 1A is an enlarged characteristic diagram of a sunrise time zone portion in FIG. 1) is completely the same as the conventional example, and the description is omitted. (2A) is a dimming characteristic of the present invention showing each dimming level at which the amount of power supplied to the tunnel lighting means is changed for each number of dimming steps. In each drawing, the horizontal axis represents time, and the vertical axis represents time. The amount of power. (A) and (c) respectively show the dimming level of the present invention, and (b) and (d) show the conventional dimming level which is proportional to the output characteristic (1) of the solar cell. The tunnel lighting means is, for example, a lighting fixture (not shown), and the tunnel lighting apparatus includes the lighting fixture, a solar cell, their peripheral circuits, and a battery for charging (none is shown).

In the dimming method of the present invention as described above, the output characteristic (1) of the solar cell gradually increases with sunrise, and when the dimming level (a) is reached, the first-stage dimming is performed. . The power set in the first-stage dimming is supplied from, for example, a charging battery to the illumination lamp, which is dimmed and turned on. Here, the first-stage dimming should be performed at a conventional dimming level (b) proportional to the output characteristic (1) of the solar cell, but in the present invention, a lower dimming level (a) is used. ). Further, when the output characteristic (1) of the solar cell increases to the dimming level (c), the second-stage dimming is performed. This dimming is actually lower than the dimming level (d). Performed at light level (c). In this way, higher dimming is performed at a level lower than the actual output of the solar cell, that is, the power for tunnel lighting is increased at an earlier time, so that a higher brightness but a lower output of the solar cell is obtained at sunrise. Even in the time zone, the illumination in the tunnel can be appropriately brightened. In the case of sunset, the same can be considered.

Here, as shown in FIG. 3, on a day when the weather is not good, the output of the solar cell is low all day, and the first or second stage dimming is performed even during the day, and the time of sunrise or sunset is set. It is very difficult to estimate the band. Next, such a case will be disclosed. Since the output of the solar cell gradually increases from zero at sunrise, it is relatively easy to set a certain time as the sunrise time zone after the output is obtained. However, as for the sunset, when the output of the solar cell decreases, it is not possible to distinguish whether the decrease has occurred due to bad weather or the approaching sunset. Therefore, the time from the sunrise time zone to the sunset time zone (the time until the output of the solar cell becomes zero) is stored in a storage device (not shown) over the past several days, and the sunset time is calculated from the average value of this time zone. The band is calculated and determined. The reason for taking the average value is that the output of the solar cell differs at sunrise or sunset time depending on the quality of the weather, and it is necessary to average the difference. That is, the sunset time is calculated from the average value of the sunrise time zone and the average value of the time from the sunrise time zone to the sunset time zone, and the light may be adjusted so that a certain time zone slightly before the sunset time is set as the sunset time zone. .

[Effects of the Invention] As described above, the present invention adjusts the number of lighting lamps in a tunnel while giving a certain time delay in accordance with a change in output characteristics of a solar cell to gradually increase the brightness in the tunnel. In the dimming method of the tunnel lighting device that performs dimming, the average value of the time until the output of the solar cell gradually increases from zero and a predetermined output is obtained over the past several days is set as a sunrise time zone. Then, over the past several days, the sunrise time zone and the sunset time are set slightly before the average value of the time until the output of the solar cell gradually decreases from a predetermined output to zero, and the sunrise time zone and the sunset time In the belt, the output greater than the actual output of the solar cell was supplied from the charging battery to the lighting fixture at the tunnel entrance, so the brightness at the tunnel entrance was directly measured. Therefore, it is possible to obtain an ideal dimming characteristic without performing, and to provide a comfortable tunnel lighting for a driver of an automobile entering the tunnel.

[Brief description of the drawings]

FIG. 1 is an explanatory view for explaining a dimming method according to one embodiment of the present invention, FIG. 1 (A) is an enlarged characteristic diagram of a sunrise time zone portion in FIG. 1, and FIG. FIG. 3 is an explanatory diagram for explaining a light control method, and FIG. 3 is an explanatory diagram for explaining a conventional light control method performed on a bad weather day. In the figure, (1) is the output characteristic of the solar cell, (2A) is the dimming characteristic indicating each dimming level at which the amount of power supplied to the lighting fixture is changed, and (a) and (c) are dimming. Level. The same reference numerals in the drawings indicate the same or corresponding parts.

Claims (1)

(57) [Claims] 1. A dimming device for a tunnel lighting device that adjusts the number of lighting devices in a tunnel and adjusts the brightness in a tunnel in a stepwise manner with a certain time delay according to a change in output characteristics of a solar cell. In the method, over the past several days, an average value of the time until the output of the solar cell gradually increases from zero to obtain a predetermined output is set as a sunrise time zone, Set a little before the average value of the time until the output of the solar cell gradually decreases from a predetermined output to zero, as a sunset time zone, and in the sunrise time zone and the sunset time zone, the actual time of the solar cell is set. A dimming method for a tunnel lighting device, characterized in that an output greater than an output is supplied from a charging battery to a lighting fixture at a tunnel entrance.