KR101238722B1 - Traffic signal state detection method and a traffic signal control device using that - Google Patents

Abstract

PURPOSE: A method for detecting a traffic signal state and a traffic signal controller using the same are provided to actively deal with each situation by separately determining a partial member and the entire member of a traffic light. CONSTITUTION: The maximum value for detecting a member of a traffic light is set(ST110). A current value is calculated by detecting a current applied to a traffic light(ST120). A difference between the maximum value and the current value is compared with a reference gap(ST140). If the difference between the maximum value and the current value exceeds the reference gap, the traffic light is determined to a partial member. If the difference between the maximum value and the current value exceeds the reference gap and the current value is below a preset reference value, the traffic light is determined to the entire member. [Reference numerals] (AA) Start; (BB,DD,FF) Yes; (CC,EE,GG) No; (HH) End; (ST110) Setting the maximum value(M); (ST115) Detecting a traffic light input current; (ST120) Calculating a current value(A); (ST135) Setting the A as the maximum value; (ST140) (M-A) <= reference gap; (ST150) Alarming a controller and reporting to a control center; (ST155) A > reference value; (ST165) Stopping a signal; (ST170) Flashing in red or yellow color

Description

Traffic signal state detection method and a traffic signal control device using that}

The present invention relates to a traffic signal state detection method and a traffic signal controller using the same, and more particularly, even when a disconnection occurs in any one of a plurality of traffic lights, it is possible to actively perform maintenance of the traffic lights. A traffic signal state detection method and a traffic signal controller using the same.

In general, traffic lights are installed in pedestrian crossings, intersections, and the like to guide traffic and stops. Typically, a traffic light for a vehicle has a basic configuration of a green light, a red light, a yellow light, and a left turn indicator may be added thereto. Pedestrian traffic lights consist of pedestrian guidance lights and stop lights. Such traffic lights were conventionally installed as incandescent bulbs, but in April 2002, the National Police Agency "LED Traffic Light Standard Guide" was enacted, and in recent years, most traffic lights have been replaced with LEDs.

A traffic signal controller for controlling a traffic light is usually equipped with a red signal member monitoring function. This function detects a disconnection or the like of the power applied to the red traffic light, and detects a state in which the red traffic light is turned off. When the red light is turned off, the yellow or red light flashes to indicate an abnormality of the light. In addition, recently, when such a red signal member is detected, the traffic signal controller transmits a signal indicating an abnormal state from the traffic control center to quickly maintain a traffic light.

In the current traffic signal control system, a traffic light is replaced with an LED, and a red signal member is detected using a current detection sensor (for example, CT, etc.) instead of a conventional voltage detection method. The red signal absence monitoring function using the CT amplifies the output of the CT to determine whether there is a disconnection, and when the disconnection is interrupted, the yellow or red traffic light blinks. The red signal is notified to the control center.

1 is a flowchart illustrating a conventional red signal absence monitoring function. Referring to FIG. 1, a current applied to a traffic light is detected (ST11), and a current value is calculated therefrom (ST13). The current value is compared with the reference value (ST15). Here, the reference value is a predetermined value for determining whether the present value represents a steady state. If the present value is greater than or equal to the reference value, it is determined that normal operation is performed, and the flow returns to the current detection step ST11. If the present value is less than the reference value, it is recognized as a red signal member (ST17), and the display of the current signal of the traffic light is stopped (ST19). Then, the red traffic light or the yellow traffic light blinks (ST21).

However, at an intersection or the like, in order to easily identify traffic lights in a plurality of lanes, as shown in FIG. 2, a red, yellow, and green traffic light (including a left turn traffic light in some cases) forms a single traffic light device. A plurality of devices are installed in combination. The same lighting control signal is applied to all of the red traffic lights 23. That is, in FIG. 2, a current branched from one power supply line is applied to three red traffic lights 23. In addition, since the current value applied to the red traffic lights 23 is varied due to temperature change or dimming control, the reference value is set relatively low in order to prevent false detection. For this reason, in the conventional red signal member detection system, the red signal member was detected only when all three red signal lamps were disconnected.

For example, as shown in FIG. 2, when the red traffic light is disconnected only in one of the three sets of traffic lights, the current value applied to the red traffic light decreases compared to the normal current, but the current value calculated therefrom is a reference value. Appears higher than. For this reason, the conventional traffic light controller has a problem that can not detect the state of some of the red signal.

However, when a failure such as FIG. 2 occurs, a vehicle that is watching only a corresponding traffic light may not recognize a red signal and may attempt to enter an intersection. In 2008, the Seoul Metropolitan Government operated the "Traffic Breakdown Report Reward System" to provide cash or gift certificates when citizens report a breakdown. However, even when such a rewarding agent is operated, it is necessary for the control center to promptly recognize and cope with some red signal absence states as well as the absence of all red signal states.

Furthermore, in the case where only some red traffic lights, not all red traffic lights, as in FIG. 2 are absent, other traffic lights are in a normal state, and thus, the traffic lights in normal operation need to be continuously operated to smooth the flow of traffic. In other words, there is a need for a method of distinguishing and detecting some and all members of the red signal.

It is an object of the present invention to provide a new traffic signal state detection method and a traffic signal controller using the same, which can discriminate and determine some members and all members of a traffic signal and actively prepare an appropriate countermeasure according to each situation.

According to an aspect of the present invention, there is provided a traffic signal state detection method, comprising: (a) setting a maximum value for detecting an absence of a traffic light; (b) calculating a current value by detecting a current applied to the traffic light; (c) comparing a difference between the maximum value and the current value with a preset reference gap; (d) if the difference between the maximum value and the current value in the step (c) exceeds the reference gap, determining that the traffic light is partially absent; And (e) if the difference between the maximum value and the current value in the step (c) exceeds the reference gap and the current value is less than or equal to the preset reference value, determining that all traffic lights are absent.

The traffic signal state detection method according to another embodiment of the present invention further includes the step of notifying the central control center of the absence of some of the traffic lights after step (d).

The traffic signal condition detecting method according to another embodiment of the present invention further includes the step of stopping the traffic signal after the step (e) and displaying a blinking red or yellow traffic light.

In a traffic signal state detection method according to another embodiment of the present invention, after the step (b), comparing the maximum value with the present value and setting the present value to the maximum value if the present value exceeds the maximum value. It further includes.

In the traffic signal state detection method according to another embodiment of the present invention, the reference gap and the reference value are set to a value lower than usual at the time of dimming control of a traffic light.

In the traffic signal state detection method according to another embodiment of the present invention, the reference gap is increased or decreased with one crossing, and the higher the one crossing, the higher the value.

In the traffic signal state detection method according to another embodiment of the present invention, the reference gap is increased or decreased according to the size of the maximum value, and the higher the maximum value has a higher value.

The traffic signal controller according to an embodiment of the present invention is configured to use any one of the traffic signal state detection methods described above.

According to the traffic signal state detection method of the present invention and the traffic signal controller using the same, by distinguishing the part and all the absence state of the traffic lights by distinguishing, even if only some of the traffic lights are disconnected to maintain the normal operation while maintaining the remaining traffic lights It is possible to notify the control center partly by the absence status, and to respond quickly. In the absence of all the status, it is effective to stop the traffic and flash the traffic lights to prevent traffic accidents caused by abnormal traffic lights.

1 is a flowchart illustrating a conventional red signal absence monitoring function;
2 is a view illustrating a state in which a part of the conventional red signal is absent;
3 is a flowchart illustrating a traffic signal state detection method according to the present invention;
4A illustrates a state in which a part of a red signal is absent, and
4B is a diagram illustrating the absence of all red signals.

Hereinafter, specific embodiments according to the present invention will be described with reference to the accompanying drawings. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

Parts having similar configurations and operations throughout the specification are denoted by the same reference numerals. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

In describing the embodiments in detail, overlapping descriptions or descriptions of obvious technology in the art are omitted. Also, in the following description, when a section is referred to as "comprising " another element, it means that it may further include other elements in addition to the described element unless otherwise specifically stated.

The traffic signal controller is installed at an intersection and the like to control the point and the lights of the traffic light to guide the progress and direction of the vehicle. Typically, red, yellow, and green traffic lights (including a left turn signal light) are installed in one traffic light unit for each driving direction, and the traffic light unit as described above can be easily identified in multiple lanes. A plurality of these are combined and installed. The traffic signal controller controls the same color traffic lights of each traffic light unit on and off simultaneously. That is, the same power supply line is commonly connected to a plurality of red traffic lights, and the power supply is interrupted by the traffic signal controller.

The present invention relates to a traffic signal state detection method and a traffic signal controller using the same when a plurality of traffic lights having the same color as described above is controlled at the same time point, lights out, partly and completely absent state of the traffic lights. The present invention is not limited to any one color such as a red traffic light, a green traffic light, and a left turn traffic light. However, since the red traffic light to stop the vehicle plays an important role, the following embodiment will be described with respect to a method for detecting the absence of the red traffic light. In addition, some parts of the red traffic light may be referred to by the term "LAMP-FAIL", and all parts may be referred to by the term "RED-FAIL".

3 is a flowchart illustrating a traffic signal state detection method according to the present invention. The method illustrated in FIG. 3 may be a method programmed in a traffic light controller in a traffic signal controller or may be a method achieved by a plurality of hardware.

Referring to FIG. 3, the process begins with setting ST110 a maximum value M. FIG. Next, the traffic light input current is detected (ST115), and the present value A is calculated from the detected current value (ST120).

The traffic light input current detection is performed by installing a current detector (such as CT) on a power line applied to the red traffic light 100 and detecting the current applied to the entire red traffic light 100. The current detected through the CT is the current value of the instrument, which is multiplied by the current ratio and the input voltage value to calculate the current value A. For example, the present value A is the power consumption value of the current traffic light, and the maximum value M is the maximum power consumption value of the traffic light.

The maximum value M may be initially set by predicting a maximum power consumption value of the traffic light. As another example, the maximum value M is set to the present value A initially detected for each period in which the traffic light control operation is reset. More preferably, the maximum value M is followed to reliably prevent false detection of the signal absence state.

Referring to FIG. 3, the present value A calculated in step ST120 is compared with the maximum value M (ST130). If the present value A is greater than the maximum value M, the present value A is set to the maximum value M (ST135). The final value M setting may be reset for each cycle. The resetting of the maximum value M at every predetermined period is for preventing the state in which the maximum value M is set too high.

In a next step, the difference between the maximum value M and the current value A is compared with a preset reference gap (ST140). The reference gap is a value for detecting the case where disconnection occurs in any one of the plurality of red traffic lights 100, and is also set to a power consumption value, for example, 4W. If the value of "M-A" is less than or equal to the reference gap, this means that all red traffic lights 100 are in normal operation. In this case, the process returns to step ST115.

If the value of "M-A" exceeds the reference gap, this means that a disconnection has occurred in the at least one red traffic light 100. As shown in FIG. 4A, when some of the red signals are absent among all the red signals, it is determined as a part of the red signal LAMP-FAIL (ST145). In the case of LAMP-FAIL, the traffic signal controller issues its own alarm and reports the LAMP_FAIL status to the central control center (ST150).

In this case, however, if the entire red traffic light 100 is not disconnected, the remaining red traffic light 100 may operate normally. Therefore, the remaining red traffic light 100 continues to operate until the dispatch of maintenance personnel in the central control center.

On the other hand, after it is determined in step ST140 that the value of "M-A" exceeds the reference gap, the present value A is compared with the reference value (ST155). The reference value is a predetermined value for determining the absence of all traffic lights. For example, since the LED signal lamp has a maximum power consumption of 5W or more, the reference value is set to 5W.

If the current value A exceeds the reference value in step ST155, this means that the LAMP-FAIL state is maintained. In this case, the process returns to step ST115 and the above-described process is repeated. However, after reporting the LAMP-FAIL after step ST140, it is not necessary to report the LAMP-FAIL status again.

If it is determined in step ST155 that the present value A is less than or equal to the reference value, as shown in FIG. 4B, it is determined as "RED-FAIL" in which all of the red traffic lights 100 are absent (ST160). In this case, signal manifestation is stopped (ST165), and the red traffic light 100 or the yellow traffic light 200 is flickered (ST170) to inform the driver of the abnormal state of the traffic light. In addition, although not illustrated in FIG. 3, the RED-FAIL status may be separately notified to the central control center. However, it is notified separately from LAMP-FAIL status.

Although the above-described traffic signal state detection method exemplifies only the red traffic light 100, the same algorithm may be applied to the yellow traffic light 200, the green traffic light 300, or other traffic lights.

Meanwhile, the traffic signal controller typically performs dimming control to prevent glare of the driver of the vehicle at night and reduce power consumption. The traffic signal controller outputs an AC 220V electric wave as a normal traffic light, but outputs an AC 110V half wave during dimming control. Accordingly, the power consumption of the traffic light in the dimming control is reduced to 50% to 70% of normal.

Accordingly, the traffic signal state detection method according to the present invention may change the reference gap and the reference value in consideration of dimming control. For example, the reference gap is usually set to 4W and 2 to 3W for dimming control. The reference value is normally set to 5W and 2.5W for dimming control. When the traffic signal controller controls dimming of the traffic light, the traffic signal controller resets the traffic light member detection process and applies the changed reference gap and reference value as described above.

On the other hand, Korea has a large daily crossover with the change of seasons, and this change in temperature causes a change in power consumption. Typically, when the maximum daily crossover is 10 degrees, the power consumption is about 0 ~ 1W difference. If the crossover is large, the gap between the maximum value and the present value will also be large. Therefore, the larger the one crossing, the higher the reference gap, and so on, the reference gap can be increased or decreased according to the one crossing. In addition, when the temperature rises in summer, the maximum value increases, but even when the maximum value increases, the reference gap may be increased or decreased according to the maximum value by increasing the reference gap. In this way, when the reference gap is increased or decreased in accordance with one crossing or the maximum value, it is possible to prevent false detection of the absence of the traffic light.

The invention described above is susceptible to various modifications within the scope not impairing the basic idea. In other words, all of the above embodiments should be interpreted by way of example and not by way of limitation. Therefore, the scope of protection of the present invention should be determined in accordance with the appended claims rather than the above-described embodiments, and should be construed as falling within the scope of the present invention when the constituent elements defined in the appended claims are replaced by equivalents.

100: red traffic light 200: yellow traffic light
300: green traffic light

Claims (8)

In a traffic signal state detection method for detecting an absence state of a traffic light,
(a) setting a maximum value for detecting absence of a traffic light;
(b) calculating a current value by detecting a current applied to the traffic light;
(c) comparing a difference between the maximum value and the current value with a preset reference gap;
(d) if the difference between the maximum value and the current value in the step (c) exceeds the reference gap, determining that the traffic light is partially absent; And
(e) if the difference between the maximum value and the present value in step (c) exceeds the reference gap and the present value is less than or equal to the preset reference value, determining that all traffic lights are absent
Traffic signal state detection method comprising a. The method of claim 1,
And after the step (d), notifying the central control center of the absence of some of the traffic lights. The method of claim 1,
Stopping the traffic signal after the step (e) and flashing a red or yellow traffic light. The method of claim 1,
And comparing the maximum value with the present value after the step (b), and setting the present value to the maximum value if the present value exceeds the maximum value. The method of claim 1,
The reference gap and the reference value is a traffic signal state detection method is set to a lower value than usual in the dimming control of traffic lights. The method of claim 5,
The reference gap is increased or decreased according to one crossing, and the higher the one crossing, the higher the traffic signal state detection method. The method of claim 5,
The reference gap is increased or decreased according to the size of the maximum value, the higher the maximum value is a traffic signal state detection method having a higher value. Traffic signal controller using the traffic signal state detection method of any one of claims 1 to 7.

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