CN109156073B

CN109156073B - L ED lighting system short circuit abnormity detection device and method, L ED lighting device

Info

Publication number: CN109156073B
Application number: CN201780030361.2A
Authority: CN
Inventors: 出岛孚
Original assignee: AI Tec System Co Ltd
Current assignee: AI Tec System Co Ltd
Priority date: 2016-03-25
Filing date: 2017-03-07
Publication date: 2020-07-24
Anticipated expiration: 2037-03-07
Also published as: WO2017163862A1; CN109156073A; JP2017174755A; JP6896215B2

Abstract

A short-circuit abnormality detection device for a L ED lighting system, a L ED lighting device having the short-circuit abnormality detection device, and a short-circuit abnormality detection method for a L ED lighting system, each of which is capable of accurately detecting a short-circuit abnormality of L ED cells including a plurality of L EDs connected in series, wherein L ED cells (10) are turned on in a predetermined lighting state for reference measurement in a state where a power supply unit (2) and a lighting device body (1) are connected by a connection line (3) for supplying power from a power supply unit (2) to the lighting device body (1), reference data is created based on a potential of a first position and a potential of a second position, and one or more short-circuits L ED (11) in the L ED cells (10) are detected by comparing the potentials of the first position and the second position or a difference between the potentials with the reference data when the L ED lighting system is operated.

Description

L ED lighting system short circuit abnormity detection device and method, L ED lighting device

Technical Field

The present invention relates to an apparatus for detecting short circuit abnormality of L ED lighting system, L ED lighting system having the same, and a short circuit abnormality detection method of L ED lighting system, and more particularly, to an apparatus for detecting short circuit of one or more L EDs in L ED units having a plurality of L EDs connected in series, L ED lighting system having the same, and a method of detecting short circuit thereof.

Background

As an illumination device having L ED units including a plurality of L EDs connected in series, there is known a linear illumination device that illuminates a detection position of a sensor such as a line sensor camera linearly in accordance with a field angle of the sensor in product inspection in various manufacturing processes for manufacturing, for example, a steel plate, a plate glass, food, paper money, etc. (see, for example, patent document 1).

Here, the L ED includes a disconnection abnormality and a short-circuit abnormality, and each L ED is different from a normal resistance and is not an element that generates a voltage drop proportional to a current flowing but an element that does not flow a current in a non-lighting state and generates a voltage drop of, for example, about 3V in a lighting state.

Therefore, if an open-circuit abnormality occurs in one of the L EDs in the L ED cell, no current flows in the L ED cell, and all of the L EDs are turned off, whereas if a short-circuit abnormality occurs in one of the L EDs in the L ED cell, the voltage drop of the L ED cell is reduced by the short-circuited L ED if the supplied currents are the same.

Prior art documents

Patent document 1: japanese laid-open patent publication No. 2007-225591

Disclosure of Invention

Technical problem to be solved by the invention

As described above, when a disconnection abnormality occurs, no current flows in the L ED cell, and therefore, this phenomenon can be used for detection, whereas, when a short-circuit abnormality occurs in one L ED of the L ED cell, it is considered that the voltage drop of the L ED cell is reduced by an amount corresponding to the L ED in which the short-circuit occurs, and detection is performed by measuring the voltage across the L ED cell, but only this is actually impossible to perform accurate detection of the short-circuit abnormality.

The reason for this is that the voltage drop of an L ED amount varies depending on the amount of current flowing in the L ED, which varies not in proportion to the amount of current nor linearly with respect to the increase in current, and there are also cases where a L ED amount of voltage drop causes a manufacturing factor deviation of + -10% with respect to the target voltage drop value, and furthermore, there are cases where a L ED amount of voltage drop varies depending on the temperature (heat generation) of L ED.

On the other hand, when illuminating the angle of view of the sensor in product inspection or the like in various manufacturing processes, an illumination unit having a configuration directly required for illumination only by L ED cells, lenses, and the like is often arranged in the manufacturing processes, a power supply unit having a power supply adjustment unit for adjusting power supplied to L ED cells of the illumination unit and a control unit for transmitting a control signal to the power supply adjustment unit is arranged at a position apart from the illumination unit, and the illumination unit and the power supply unit are connected by a connection wire.

Since the connection line is formed using a material having a small resistance value, the resistance value of the connection line can be generally ignored, but may not be ignored in an L ED lighting system arranged in a wide space such as a factory.

In this situation, it is conceivable to measure the voltage drop of all L EDs periodically to detect short-circuit abnormality of each L ED directly, in order to detect short-circuit abnormality accurately, but in many cases, for example, in an illumination device used for product inspection in various manufacturing processes, since the arrangement interval of L EDs is small, a plurality of L ED units are provided, and each L ED unit has about 10 to 15L ED. units, in order to illuminate a wide range brightly and uniformly, it is not practical to measure the voltage drop of all L EDs periodically.

The present invention has been made in view of such circumstances, and an object thereof is to provide a short-circuit abnormality detection device for a L ED lighting system, which can accurately detect a short-circuit abnormality of a L ED cell including a plurality of L EDs connected in series, a L ED lighting system including the same, and a short-circuit abnormality detection method for a L ED lighting system.

Technical solution for solving technical problem

In order to solve the above-mentioned technical problems, a short circuit abnormality detection device of a L ED lighting system according to a first aspect of the present invention is a short circuit abnormality detection device of a L ED lighting system that detects a short circuit abnormality in a L ED lighting system including L ED units having a plurality of L EDs connected in series, the L ED lighting system is a system including a lighting section having the L ED unit and a power supply section for supplying driving power to the L ED units of the lighting section, the short circuit abnormality detection device includes a first detection unit for detecting a potential of a first position of the L ED unit, a second detection unit for detecting a potential of a second position lower in potential than the first position in the L ED unit, a reference data setting unit for lighting the L ED unit in a predetermined lighting state based on a predetermined trigger for reference measurement in a state where the power supply section and the lighting section are connected, and a reference data setting unit for lighting the L ED unit in a predetermined lighting state based on a predetermined trigger when the first detection unit detects the short circuit abnormality and the second detection unit detects the short circuit abnormality, and the reference data setting unit compares the potential with the reference data stored in the reference data detection unit 5392 ED detection unit, and the short circuit abnormality detection unit compares the short circuit abnormality detection unit with the short circuit abnormality detection unit.

A short-circuit abnormality detection method of a L ED illumination system according to a second aspect of the present invention is a short-circuit abnormality detection method of a L2 ED illumination system for detecting a short-circuit abnormality in a L1 ED illumination system including L0 ED cells having a plurality of L EDs connected in series, the L3 ED illumination system including an illumination section including the L ED cell and a power supply section for supplying driving power to the L ED cell of the illumination section, the short-circuit abnormality detection method including a reference data setting step of lighting the L ED cell in a predetermined lighting state for reference measurement in a state where the power supply section and the illumination section are connected, and making reference data based on a potential of a first position in the L ED cell and a potential of a second position in the L ED cell lower than the first position and storing the reference data in a storage section, and a short-circuit detection step of comparing a difference between the first position and the second position with the reference potential or between the reference potentials of the two positions in the L ED illumination system in operation, the short-circuit abnormality detection step of comparing L with the reference data set by the reference data or the reference data L.

In the first and second aspects, the L ED cells are lit in a predetermined lit state for reference measurement in a state where the power supply unit and the illumination unit are connected, reference data is created based on the potential at the first position and the potential at the second position, and a short circuit of one or more L EDs in the L ED cell is detected by comparing the potentials at the first position and the second position or a difference between the potentials with the reference data when the L ED system is operated.

A L ED lighting system short-circuit abnormality detection apparatus according to a third aspect of the present invention is a short-circuit abnormality detection apparatus of a L2 ED lighting system that detects a short-circuit abnormality in a L1 ED lighting system including L0 ED units having a plurality of L EDs connected in series, the L ED lighting system being a system including a lighting unit having the L ED unit and a power supply unit for supplying driving power to the L ED unit of the lighting unit, the short-circuit abnormality detection apparatus including a detection unit for detecting a potential at a predetermined position of the L ED unit, a reference data setting unit for lighting the L ED unit in a predetermined lighting state based on a predetermined trigger for reference measurement in a state where the power supply unit and the lighting unit are connected, and making reference data based on a potential detected by the detection unit and storing the reference data in a storage unit, and a short-circuit detection unit for comparing the potential detected by the detection unit with the reference data set by the reference data unit and comparing the potential detected by the L ED lighting system with one or more ED data stored in the storage unit L, and detecting one short-circuit abnormality in the plurality of the reference data stored in the storage unit L.

A method of detecting a short-circuit abnormality of a L ED lighting system according to a fourth aspect of the present invention is a method of detecting a short-circuit abnormality of a L2 ED lighting system in a L1 ED lighting system including L0 ED units having a plurality of L EDs connected in series, wherein the L ED lighting system is a system including a lighting unit having the L ED unit and a power supply unit for supplying driving power to the L ED unit of the lighting unit, the method includes a reference data setting step of lighting the L ED unit in a predetermined lighting state in a state where the power supply unit and the lighting unit are connected for reference measurement, and generating reference data based on a potential of a predetermined position in the L ED unit and storing the reference data in a storage unit, and a short-circuit detection step of detecting a short-circuit abnormality of one or more of the L ED units L by comparing the potential of the predetermined position with the reference data stored in the reference data setting step when the L ED lighting system is operated.

In the third and fourth aspects, the L ED cells are lit in a predetermined lighting state for reference measurement based on a predetermined trigger in a state where the power supply unit and the illumination unit are connected, and reference data is created based on a potential at a predetermined position of the L ED cells and stored in a storage unit, and the potential at the predetermined position is compared with the reference data when the L ED system is operated, thereby detecting a short circuit of one or more L EDs in the L ED cells.

Effects of the invention

According to the present invention, it is possible to accurately detect a short-circuit abnormality in a L ED cell including a plurality of L EDs connected in series.

Drawings

Fig. 1 is a schematic configuration diagram of an L ED lighting system according to a first embodiment of the present invention.

Fig. 2 is an example of reference data of the L ED lighting system of the first embodiment.

Fig. 3 shows an example of the display unit of the L ED lighting system.

Fig. 4 shows an example of the result of measuring the potential difference between the potential at the first position and the potential at the second position in the L ED lighting system.

Fig. 5 shows an example of the result of measuring the potential difference between the potential at the first position and the potential at the second position in the L ED lighting system.

Fig. 6 is a schematic configuration diagram of an L ED lighting system according to a second embodiment of the present invention.

Fig. 7 is an example of reference data of an L ED lighting system of the second embodiment.

Fig. 8 is a schematic configuration diagram of an L ED lighting system according to a third embodiment of the present invention.

Fig. 9 is an example of reference data of the L ED lighting system of the third embodiment.

Fig. 10 is a schematic configuration diagram of an L ED lighting system according to a fourth embodiment of the present invention.

Fig. 11 is an example of reference data of an L ED lighting system of the fourth embodiment.

Description of the reference symbols

The lighting device comprises a lighting device body, a power supply unit, a 3 connecting wire, a 4 short-circuit detection device, a 10: L ED unit, a 11: L ED unit, a 13: high-potential-side input terminal, a 14: low-potential-side input terminal, a 21: high-potential-side terminal, a 22: low-potential-side terminal, a 23: dimming input unit, a 24: constant current circuit, a 41: first detection element, a 42: second detection element, a 43: control unit, a 44: storage unit, a 45: dimming value input unit, a 46: trigger input unit, a 47: display unit, a 48: sequentially connected circuit, and a 49: temperature sensor.

Detailed Description

An L ED lighting system according to a first embodiment of the present invention will be described below with reference to the drawings.

The L ED lighting system is a system for linearly illuminating a detection position detected by an inspection sensor such as a line sensor, and as shown in fig. 1, includes a lighting device main body 1 as a lighting unit, a power supply unit 2 as a power supply unit, a connection line 3 for connecting the lighting device main body 1 and the power supply unit 2 and supplying power from the power supply unit 2 to the lighting device main body 1, and a short-circuit detection device 4, and the connection line 3 supplies drive power to the lighting device main body 1.

The illumination device main body 1 includes at least one L ED cell 10, and in the present embodiment, as shown in fig. 1, includes a plurality of L ED cells 10, each L ED cell 10 includes a plurality of (for example, 10 or more) L ED11 connected in series, and the plurality of L ED11 is mounted on a L ED board and connected in series, and another circuit element such as a resistor may be added to each L ED cell 10, and the illumination device main body 1 includes a high potential side input terminal 13 connected to the high potential side of each L ED cell 10, and a low potential side input terminal 14 connected to the low potential side of each L ED cell 10.

The power feeding unit 2 includes a high-potential side terminal 21, a low-potential side terminal 22, and a dimming input unit 23 for outputting power from a dc power supply, as shown in fig. 1, the power feeding unit 2 includes a constant current circuit 24 corresponding to each L ED cell 10, and a driving current adjusted by the constant current circuit 24 according to an input of the dimming input unit 23 flows through the high-potential side terminal 21, the connection line 3, the high-potential side input terminal 13, each L ED cell 10, the low-potential side input terminal 14, the connection line 3, and the low-potential side terminal 22, and on the other hand, the dimming input unit 23 may be a member for converting a dimming value from a manually operated operation unit into a digital signal and transmitting the digital signal to a control unit 43 described below, may be a signal input unit for transmitting a digital signal for dimming input from the outside to the control unit 43 described below, or may be a signal input unit for transmitting the digital signal for.

The short-circuit detector 4 includes a first detection element 41 for detecting a potential (a potential at a first position) on the high-potential-side input terminal 13 side higher than L ED11 on the highest potential side among the L ED cells 10, a second detection element 42 for detecting a potential (a potential at a second position) on the low-potential-side input terminal 14 side lower than L ED11 on the lowest potential side among the L ED cells 10, a control unit 43 including a known microcomputer for receiving detection results detected by the

detection elements

41 and 42, a storage unit 44 including a nonvolatile memory such as a semiconductor memory, and a dimming value input unit 45 connected to the control unit 43 and transmitting a dimming digital signal of the dimming input unit 23 to the control unit 43, and a current measurement unit for measuring an actual drive current flowing through each L ED cell 10 and transmitting the measured value to the control unit 43 may be considered.

The short-circuit detection device 4 further includes a trigger input unit 46 connected to the control unit 43. In the present embodiment, the trigger input unit 46 is a button disposed on the back surface of the main body case of the power supply unit 2, but the trigger input unit 46 may be configured to receive a trigger signal from the outside and transmit the trigger signal to the control unit 43.

The short-circuit detection device 4 further includes a display unit 47 such as a liquid crystal display device connected to the control unit 43, and the display unit 47 is configured to perform a predetermined display under the control of the control unit 43.

In the present embodiment, the control unit 43 and the storage unit 44 are configured in a single microcomputer chip such as an MCU (Microcontroller). Each of the

detection elements

41 and 42 may be an element having a wiring and an a/D converter for performing analog-to-digital conversion of the potential at each position and transmitting the converted potential to the control unit 43 as in the present embodiment, or may be a potentiometer with a wireless transmission function for performing analog-to-digital conversion of the potential at each position and transmitting the converted potential to the control unit 43. In addition, any other element may be used as long as it can transmit the potential at each position to the control unit 43.

The control unit 43 operates based on a program stored in the storage unit 44, and specifically, performs the following operation.

When the button of the trigger input unit 46 is operated in a state where the power supply unit 2 and the lighting apparatus body 1 are connected as shown in fig. 1 using the connection line 3 which is preferably supplied with power at the installation position which is actually provided, the reference data creating process is performed by the program. The power supply unit 2 and the lighting apparatus body 1 may be connected to each other, and the trigger signal may be transmitted from the trigger input unit 46 to the control unit 43 when a predetermined time has elapsed.

The reference data creating process is configured to obtain the reference data (reference potential difference) of each level while sequentially increasing the current amount by, for example, 16 levels, and further, in the present embodiment, the reference data (reference potential difference) of each level is obtained, and further, the dimming input unit 23 is configured to increase the current amount by a fixed amount (for example, 60mA) for each level, after receiving the above-described trigger signal (step 1-1), in a state where no current flows in each L ED cell 10, control each constant current circuit 24 to cause each L ED cell 10 to light up each L ED cell 10 for reference measurement (step 1-2), the control unit 43 receives the potential difference (reference potential difference) between the first position and the second position detected by each detecting

element

41, 42 in this state and stores the potential difference in the storage unit 44 in correspondence with the dimming level (steps 1-3), further, signals from the detecting

elements

41, 42 of each L ED cell 10 are input to the control unit 43 via the sequential connection circuit 48, and, as in the case where the lighting control unit is capable of sequentially providing the lighting control unit 41, the lighting unit 43, the lighting control unit may be provided as if necessary, or if the lighting unit is sequentially connected 3648.

Next, by repeating the same control as in steps 1-2 and 1-3 described above, the light control input unit 23 is sequentially controlled so that the constant current circuits 24 cause L ED cells 10 to flow current amounts of 2 nd to 16 th ranks, so that L ED cells 10 are turned on for reference measurement, and the control unit 43 receives the potential difference (reference potential difference) between the first position and the second position detected by the

detection elements

41 and 42 in each state and stores the potential difference in the storage unit 44 in accordance with the light control level (steps 1-4).

After the reference data is created in this manner, when the L ED lighting system is operating normally, the control unit 43 detects a short-circuit abnormality by the program, and the control unit 43 displays the result on the display unit 47 or the control unit 43 transmits a signal indicating the result to the outside.

The short-circuit abnormality detection is to detect L ED short-circuit presence and/or state by comparing the measured potential difference between the first position and the second position with the reference potential difference at the corresponding dimming level in the reference data and determining the position of the difference between the measured potential difference and the reference potential difference with respect to the first threshold value, the second threshold value, and the third threshold value for each L ED cell 10 in the normal operation, and the first threshold value, the second threshold value, and the third threshold value are prepared for each L ED cell 10.

When the dimming level of each L ED cell 10 during normal operation is between, for example, the 1 st level and the 2 nd level, the controller 43 interpolates the reference potential difference between the first level and the second level using the reference potential difference of the first level and the reference potential difference of the second level of the dimming level, and also interpolates the first threshold to the third threshold in the same manner, thereby detecting L ED presence/absence and/or state of short circuit.

The temperature sensor may be provided in the lighting device main body 1, and the first to third threshold values may be corrected based on the detection value of the temperature sensor, and the degree of correction may be appropriately set according to the characteristic of L ED 11.

The first to third threshold values are set for each dimming state based on the reference potential difference, and further, for each L ED cell 10 based on the reference data of each L ED cell 10, the first threshold value is a value obtained by dividing the reference potential difference of each dimming state by the number of L ED11 of the L ED cell 10 (the reference potential difference of one L ED 11) by 0.3 to 0.7 times, preferably 0.5 times, the second threshold value is a value obtained by adding the first threshold value to the reference potential difference of the one L ED11, and the third threshold value is a value obtained by adding the second threshold value to the reference potential difference of the one L ED 11.

When the difference between the measured potential difference and the reference potential difference for each L ED cell 10 exceeds the first threshold value, the controller 43 determines that one L ED11 of the L ED cell 10 is short-circuited, when the difference exceeds the second threshold value, determines that 2L ED11 of the L ED cell 10 is short-circuited, and when the difference exceeds the third threshold value, determines that 3 or more L ED11 of the L ED cell 10 are short-circuited, and the controller 43 displays the result on the display 47 as shown in fig. 3, for example.

In the present embodiment, the reference potential difference and the actually measured potential difference are compared, but the potentials at the first position and the second position may be directly used as the reference data, and the reference data may be directly compared with the potentials at the first position and the second position during operation.

As described above, in the present embodiment, in a state where the power supply unit 2 and the illumination apparatus main body 1 are connected using the connection line 3 that supplies power from the power supply unit 2 to the illumination apparatus main body 1 at an installation position that is preferably actually provided, each L ED cell 10 is lit in a predetermined lit state for reference measurement, reference data is created based on the potential at the first position and the potential at the second position, and a short circuit of one or more L EDs in the L ED cell is detected by comparing the potentials at the first position and the second position or the difference between the potentials with the reference data when the L ED illumination system is operated.

When the connection line 3 used at a position where the connection line is actually provided is not used, but another connection line 3 is used, reference data based on variations in manufacturing factors such as voltage drop of L ED11 constituting each L ED cell 10 is also created.

Incidentally, the lighting apparatus main body 1, the power supply unit 2, the connection line 3, and the short-circuit detection device 4 described in the above embodiment were prepared and connected as described above, and as a result, reference potential differences at the first position and the second position of each of the L ED cells 10 were measured in each of the dimming states, and as a result, data such as those shown in fig. 4 and 5 were obtained, fig. 4 is data of a reference potential difference with respect to a L ED cell 10 having the smallest potential difference among a plurality of L ED cells 10, and fig. 5 is data of a reference potential difference with respect to a L ED cell 10 having the largest potential difference, and it was found that the reference potential difference was about 7 to 13% larger in each of the dimming states with respect to the data of fig. 4, and it was found that the variation in the manufacturing factor of the voltage drop of each of L ED cells was never small.

An L ED lighting system according to a second embodiment of the present invention will be described below with reference to the drawings.

The L ED lighting system of the present embodiment is a system in which a temperature compensation function is added to the short circuit detection device 4 of the L ED lighting system of the first embodiment, and the other configurations and functions are the same as those of the first embodiment, and therefore, the description thereof is omitted.

Specifically, as shown in fig. 6, the short-circuit detection device 4 of the L ED lighting system according to the present embodiment includes a temperature sensor 49 disposed in the lighting device main body 1, and the temperature sensor 49 may be a device that measures the temperature of the L ED substrate on which one L ED cell 10 out of the L ED cells 10 is mounted, a device that measures the temperature of the L ED substrate of each of the L ED cells 10, or a device that measures the ambient temperature or other components in the lighting device main body 1.

In the present embodiment, when the button of the trigger input unit 46 is operated in a state where the power supply unit 2 and the lighting apparatus main body 1 are connected as shown in fig. 6 using the connection line 3 that supplies power at the installation position that is preferably actually provided, the control unit 43 also performs the reference data creation process using the program.

The reference data creating process is performed such that, after receiving the trigger signal as in the first embodiment (step 2-1), the light control input unit 23 is controlled such that each constant current circuit 24 causes the current amount of the 1 st order to flow through each L ED cell 10 and each L ED cell 10 is turned on for reference measurement in a state where no current flows through each L ED cell 10 as in the first embodiment (step 2-2), and the control unit 43 receives the potential difference (reference potential difference) between the first position and the second position detected by each of the

detection elements

41 and 42 in this state and stores the potential difference in the storage unit 44 in correspondence with the light control level (step 2-3).

Next, by repeating the same control as in the above-described steps 2-2 to 2-3, the dimming input unit 23 is sequentially controlled so that the constant current circuits 24 cause L ED cells 10 to flow current amounts of 2 nd to 16 th ranks, and the L ED cells 10 are turned on for reference measurement, the control unit 43 receives the potential difference (reference potential difference) between the first position and the second position detected by the detection elements 41 and 42 in each state and stores the potential difference in the storage unit 44 in correspondence with the respective dimming levels (step 2-4), and then, after step 2-4, the measurement result of the temperature sensor 49 is stored in the storage unit 44 (step 2-5), the measurement result of the temperature sensor 49 is associated with the respective reference potential differences, and in this embodiment, the measurement result of the temperature sensor 49 after step 2-4 may be stored in the storage unit 44, but in the storage unit 44, the measurement result of the temperature sensor 49 corresponding to each dimming may be stored in the storage unit 44 at each step 2-3, and data of the first position and the second position may be stored in the storage unit 44 as the reference potential difference data, and the second position data may be stored in the storage unit 42 as shown in fig. 7.

After the reference data is created in this manner, when the L ED lighting system is operating normally, the control unit 43 performs short-circuit abnormality detection using the program, and the control unit 43 displays the result on the display unit 47 or the control unit 43 transmits a signal indicating the result to the outside, as in the first embodiment.

Here, in the first embodiment, the difference between the actually measured potential difference and the reference potential difference is compared with the first to third threshold values to determine the short-circuit abnormality, but in the present embodiment, the difference between the result of temperature compensation of one of the actually measured potential difference and the reference potential difference and the other is compared with the first to third threshold values to determine the short-circuit abnormality.

For example, a predetermined coefficient or a predetermined temperature compensation arithmetic expression is applied to a temperature difference between a temperature associated with a reference potential difference of reference data and a measurement result of the temperature sensor 49 at the time of measurement of the measured potential difference to obtain a potential difference correction value, and the potential difference correction value is applied to one of the measured potential difference and the reference potential difference and then compared with the first to third threshold values.

The predetermined coefficient may be a temperature coefficient determined according to L ED, and is a coefficient obtained by measuring the temperature characteristics of L ED11 and using the average value of the measured temperature characteristics.

In the case of this embodiment, short-circuit detection can be performed in consideration of the temperature characteristics of each L ED11 in addition to the manufacturing factor variation in the resistance of the connection line of the L ED lighting system arranged in a wide space such as a factory and the voltage drop of L ED.

An L ED lighting system according to a third embodiment of the present invention will be described below with reference to the drawings.

The L ED lighting system of the present embodiment is a system in which the first detection element 41 of the short circuit detection device 4 of the L ED lighting system of the second embodiment is omitted as shown in fig. 8, and other configurations and functions are the same as those of the second embodiment, and therefore, the description thereof is omitted.

In the present embodiment, when the button of the trigger input unit 46 is operated in a state where the power supply unit 2 and the lighting apparatus main body 1 are connected as shown in fig. 8 using the connection line 3 for supplying power at the installation position which is preferably actually provided, the control unit 43 also performs the reference data creation process by using the program.

The reference data creating process is performed such that, after receiving the trigger signal as in the first embodiment (step 3-1), the dimming input unit 23 is controlled such that each constant current circuit 24 causes the current amount of the 1 st level to flow through each L ED cell 10 and each L ED cell 10 is turned on for reference measurement in a state where no current flows through each L ED cell 10 as in the first embodiment (step 3-2), and the control unit 43 receives the potential (reference potential) of the second position detected by each detection element 42 in this state and stores the potential in the storage unit 44 in accordance with the dimming level (step 3-3).

Next, by repeating the above-described steps 3-2 to 3-3, the light control input unit 23 is sequentially controlled so that the constant current circuits 24 cause L ED cells 10 to flow current amounts of 2 nd to 16 th ranks, and the L ED cells 10 are turned on for reference measurement, the control unit 43 receives the potentials (reference potentials) at the second positions detected by the detection elements 42 in the respective states and stores the potentials in the storage unit 44 in association with the respective light control levels (step 3-4), and then, after the step 3-4, the measurement results of the temperature sensors 49 are stored in the storage unit 44 (step 3-5), and the measurement results of the temperature sensors 49 are associated with the respective reference potential differences, in the present embodiment, the measurement results of the temperature sensors 49 are stored in the storage unit 44 after the step 3-4, but the measurement results of the temperature sensors 49 corresponding to the respective light controls may be stored in the storage unit 44 at the time of the respective steps 3-3, and the reference data shown in fig. 9 may be created and stored in the storage unit 44.

The short-circuit abnormality detection is to detect the presence and/or state of a short circuit of L ED by comparing the measured potential at the second position with the reference potential at the corresponding dimming level in the reference data and determining at which position the difference between the measured potential and the reference potential is relative to the threshold value, for each L ED cell 10 during normal operation.

The threshold is set for each dimming state based on the reference potential, and may be set for each L ED cell 10 based on the reference data of each L ED cell 10.

When the dimming level of each L ED cell 10 during normal operation is between, for example, the 1 st level and the 2 nd level, the control unit 43 interpolates the reference potential between the 2 nd level and the 2 nd level using the reference potential of the 1 st level of the dimming level and the reference potential of the 2 nd level of the dimming level, and also interpolates the threshold value in the same manner to detect the presence or absence and/or state of a short circuit of L ED based on the interpolation.

In this case, short-circuit detection can be performed in consideration of variations in manufacturing factors such as the resistance of the connection line of the L ED lighting system and the voltage drop of L ED, which are arranged in a wide space such as a factory.

An L ED lighting system according to a fourth embodiment of the present invention will be described below with reference to the drawings.

As shown in fig. 10, this L ED lighting system includes a lighting device main body 5, a power supply unit 6 as a power supply unit, a connection line 3 for connecting the lighting device main body 5 and the power supply unit 6 and supplying power from the power supply unit 6 to the lighting device main body 5, and a short-circuit detection device 4 similar to the second embodiment, the connection line 3 supplies at least a drive voltage to the lighting device main body 1.

In this embodiment, the lighting apparatus main body and the power supply unit are changed from the second embodiment, but the short-circuit detection is performed by the short-circuit detection device 4 similar to the second embodiment.

The lighting apparatus main body 5 includes at least one L ED cell 50, and in the present embodiment, as shown in fig. 10, a plurality of L ED cells 50, each L ED cell 50 includes a plurality of (for example, 10 or more) L ED51 connected in series, and a plurality of L ED51 is mounted on a L ED board and connected in series, each L ED cell 50 further includes a current limiting resistor 52, and other circuit elements can be added thereto, and the lighting apparatus main body 5 includes a high potential side input terminal 53 connected to a high potential side of each L ED cell 50, and a low potential side input terminal 54 connected to a low potential side of each L ED cell 50.

The power feeding unit 6 includes a high potential side terminal 61, a low potential side terminal 62, and a dimming input unit 63, which output power from a constant voltage PWM (pulse width modulation) DC power supply, the power feeding unit 6 is configured to supply power having a duty ratio corresponding to an input of the dimming input unit 63 to each L ED unit 50 via the high potential side terminal 61, the connection line 3, the high potential side input terminal 53, the low potential side input terminal 54, the connection line 3, and the low potential side terminal 62. the dimming input unit 63 may be a member that converts a duty ratio signal from a manually operated operation unit into a digital signal and transmits the digital signal to the control unit 43 described below, may be a signal input unit that transmits a digital signal for duty ratio adjustment, which is input from the outside, to the control unit 43 described below, or may include both of these.

The first detecting elements 41 of the short-circuit detecting device 4 are arranged to detect a potential (potential at the first position) on the high-potential side input terminal 53 side higher than L ED51 on the highest potential side in the L ED units 50, and the second detecting elements 42 are arranged to detect a potential (potential at the second position) on the low-potential side input terminal 54 side lower than L ED51 on the lowest potential side in the L ED units 50. further, the dimming digital signal of the dimming input unit 63 is transmitted to the control unit 43 through the dimming value input unit 45. alternatively, instead of the dimming digital signal, an actual drive current flowing through each L ED unit 10 may be measured and the measured value may be transmitted to the control unit 43.

When the button of the trigger input unit 46 is operated in a state where the power supply unit 6 and the lighting apparatus main body 5 are connected as shown in fig. 10 using the connection line 3 which is preferably supplied with power at the installation position which is actually provided, the reference data creating process is performed by the program. The power supply unit 6 and the lighting apparatus main body 5 may be connected to each other, and the trigger signal may be transmitted from the trigger input unit 46 to the control unit 43 when a predetermined time has elapsed.

The reference data creation process is performed such that, after receiving the trigger signal (step 4-1), the dimming input unit 63 is controlled so that the power supply unit 6 supplies power of a predetermined duty ratio to each L ED cell 50 to light each L ED cell 50 for reference measurement (step 4-2), the control unit 43 receives the difference (reference potential difference) between the potentials at the first position and the second position (the potential when a voltage is applied to each L ED cell 50) detected by each

detection element

41, 42 in this state and stores the difference in the storage unit 44 (step 4-3), and the measurement result of the temperature sensor 49 at this time is also stored in the storage unit 44 in correspondence with the reference potential difference (step 4-4), whereby reference data as shown in fig. 11 is created and stored in the storage unit 44.

The short-circuit abnormality detection is performed by comparing the measured potential difference at the first position and the second position with the reference potential difference in the reference data for each L ED cell 50 during normal operation, and determining L ED whether or not there is a short circuit and/or the state of the short circuit by determining the position of the difference between the measured potential difference and the reference potential difference with respect to the first threshold value, the second threshold value, and the third threshold value, as in the second embodiment.

The predetermined coefficient may be a temperature coefficient determined according to L ED, and is a coefficient obtained by measuring the temperature characteristics of L ED51 and using the average value of the measured temperature characteristics.

In the case of this embodiment, short-circuit detection can be performed in consideration of the temperature characteristics of each L ED51 in addition to the manufacturing factor variation in the resistance of the connection line of the L ED lighting system arranged in a wide space such as a factory and the voltage drop of L ED.

In the L ED lighting system according to the fourth embodiment, the first detection element of the short-circuit detection device 4 can be omitted.

Even in this case, when the button of the trigger input unit 46 is operated in a state where the power supply unit 6 and the lighting apparatus main body 5 are connected using the connection line 3 for supplying power at the installation position actually set, the control unit 43 performs the reference data creation process by using the program.

The reference data creating process is performed such that, upon receiving the trigger signal as in the fourth embodiment (step 5-1), the light control input unit 63 is controlled such that the power supply unit 6 supplies power of a predetermined duty ratio to each L ED cell 50, each L ED cell 50 is turned on for reference measurement (step 5-2), the control unit 43 receives the potential (reference potential) at the second position detected by each detection element 42 in this state and stores the received potential in the storage unit 44 (step 5-3), and the measurement result of the temperature sensor 49 at this time is also stored in the storage unit 44 in correspondence with the reference potential (step 5-4), thereby creating reference data and storing the reference data in the storage unit 44.

The short-circuit abnormality detection is to detect the presence and/or state of a short circuit of L ED by comparing the measured potential at the second position with the reference potential of the reference data for each L ED cell 50 during normal operation, and determining at which position the difference between the measured potential and the reference potential is relative to a threshold value.

The threshold is set for each L ED cell 10 based on the reference data for each L ED cell 10.

In the first, second, and fourth embodiments, the first potential is measured for each L ED cell, but the first potential may be measured for only one of L ED cells and used as the first potential of the other L ED cell.

In the above embodiments, although the case where the light is modulated for each L ED cell using the constant current circuit and the case where the light is modulated using the PWM control are described, the short circuit detection of L ED can be performed as described above by using the technique described in the above embodiments and the technique equivalent thereto even when the constant current control and the constant voltage control are performed using other methods.

Claims

1. A short-circuit abnormality detection device for L ED lighting system detects short-circuit abnormality in a L ED lighting system including L ED units having a plurality of L EDs connected in series,

the L ED lighting system is a system including a lighting section having the L ED units, and a power supply section for supplying driving power to the L ED units of the lighting section,

the short circuit abnormality detection device includes:

a first detecting unit for detecting a potential of a first position of the L ED unit;

a second detection unit for detecting a potential at a second position lower than the first position in the L ED unit;

reference data setting means for increasing the current amount in a plurality of steps from low to high in accordance with a predetermined trigger in a state where the power supply unit and the illumination unit are connected, thereby lighting the L ED unit in predetermined lighting states for reference measurement at different dimming levels in accordance with different current amounts, and creating reference data based on the potential detected by the first detection means and the potential detected by the second detection means in the lighting states, and storing the reference data in a storage unit, and a method for controlling the lighting device

A short circuit detection unit which detects a short circuit of one or more L EDs of the L ED units by comparing the potentials detected by the first detection unit and the second detection unit or the difference between the potentials with the reference data stored by the reference data setting unit when the L ED lighting system is operating.

2. The L ED lighting system short circuit abnormality detection device of claim 1,

the power supply unit has a constant current circuit for adjusting the amount of current flowing in the L ED cells of the lighting unit,

the reference data setting unit causes the L ED cell to light up in the predetermined lighting state for the reference measurement by controlling the amount of current supplied to the L ED cell by the constant current circuit.

3. A short-circuit abnormality detection device for L ED lighting system detects short-circuit abnormality in a L ED lighting system including L ED units having a plurality of L EDs connected in series,

the short circuit abnormality detection device includes:

a detection unit for detecting a potential of a predetermined position of the L ED unit;

reference data setting means for increasing the current amount in a plurality of steps from low to high in dimming according to a predetermined trigger in a state where the power supply unit and the illumination unit are connected, thereby lighting the L ED unit in predetermined lighting states for reference measurement at different dimming levels in different current amounts, and creating reference data based on the potential detected by the detection means in each of the lighting states and storing the reference data in a storage unit, and a method for controlling the lighting device

A short detection unit that detects a short of one or more L ED of the L ED units by comparing the potential detected by the detection unit with the reference data stored by the reference data setting unit when the L ED lighting system is operating.

4. The L ED lighting system short circuit abnormality detection device of claim 3,

5. An L ED lighting system, comprising:

a lighting section comprising L ED cells having a plurality of L EDs connected in series;

a power supply unit for supplying driving power to the L ED cells of the lighting unit, and

the short circuit abnormality detection device according to any one of claims 1 to 4.

6. A short circuit abnormality detection method of L ED lighting system detects short circuit abnormality in L ED lighting system including L ED unit having a plurality of L EDs connected in series,

the short circuit abnormality detection method includes:

a reference data setting step of increasing the current amount at a plurality of levels from low to high in a dimming state in which the power supply unit and the illumination unit are connected, thereby lighting the L ED cell in predetermined lighting states for reference measurement at different dimming levels, respectively, in different current amounts, and creating reference data based on a potential at a first position in the L ED cell and a potential at a second position in the L ED cell, which is lower than the first position, in each of the lighting states, and storing the reference data in a storage unit, and a method of controlling the lighting apparatus

A short circuit detection step of detecting a short circuit of one or more L EDs in the L ED cells by comparing the potentials of the first position and the second position or the difference between the potentials with the reference data stored in the reference data setting step when the L ED lighting system is in operation.

7. The L ED lighting system short circuit abnormality detection method of claim 6,

in the reference data setting step, the L ED cell is lighted in the predetermined lighting state for the reference measurement by controlling an amount of current supplied to the L ED cell by the constant current circuit.

8. A short circuit abnormality detection method of L ED lighting system detects short circuit abnormality in L ED lighting system including L ED unit having a plurality of L EDs connected in series,

the short circuit abnormality detection method includes:

a reference data setting step of increasing the current amount at a plurality of levels from low to high in a state where the power supply unit and the illumination unit are connected, thereby lighting the L ED cells in predetermined lighting states at different current amounts for reference measurement at different dimming levels, respectively, and creating reference data based on the potential at a predetermined position in the L ED cell in each of the lighting states, and storing the reference data in a storage unit, and an

A short circuit detection step of detecting a short circuit of one or more L EDs in the L ED cells by comparing the potential of the predetermined position with the reference data stored in the reference data setting step when the L ED lighting system is operating.

9. The L ED lighting system short circuit abnormality detection method of claim 8,