KR102590510B1 - Monitoring system for light emitting apparatus - Google Patents

Abstract

The present invention includes a lighting unit 300 each including a plurality of lighting modules; A power supply unit 100 that supplies power to a plurality of lighting modules 310, 320, and 330; and a monitoring unit 200 that measures the current of each of the lighting modules 310, 320, and 330; Includes, the monitoring unit 200 is a switching element provided with a parasitic element connected to the output side of the lighting module (310, 320, 330); and a controller 210 that turns off the switching element to measure the current passing through the parasitic element and controls the switching element to turn on to reduce power consumption generated when measuring the current. Provides a monitoring system for lighting that includes.

Description

Monitoring system for lighting {MONITORING SYSTEM FOR LIGHT EMITTING APPARATUS}

The present invention relates to a monitoring system for lighting.

In general, LED devices have excellent energy savings, can be used semi-permanently due to their long lifespan, are eco-friendly, and have high-speed response, so they are attracting attention as next-generation light sources.

Recently, the problem of low luminance of LED devices has been greatly improved, and the application field is expanding throughout the industry, such as light sources for backlights of LCD panels or lighting devices.

An LED device is a semiconductor device that emits light when a forward voltage is applied. The optical output of an LED device is determined by the forward current, and as can be seen from the current-voltage characteristic curve of the LED, a small change in the forward voltage (Vf) causes a very large change in the forward current.

In order to detect the malfunction of a lighting device (for example, a street light) using an LED with these characteristics, the malfunction was detected through the current of the lighting module. This prior art is shown in Figure 1.

Figure 1 is a circuit diagram showing a conventional lighting device.

Referring to Figure 1, a conventional lighting device (for example, a street light) uses a resistor (a) connected in series to measure the current of the LED modules (10, 11, 12, 13, 14, 15) and each resistance An amplification circuit (b) is provided to amplify the signal measured at both ends, and the current is monitored by measuring the voltage between both ends of the resistor.

However, the prior art has a problem in that, as current is measured through resistance, power loss inevitably occurs due to power consumption due to resistance and circuit operation.

For example, when calculating the power consumption using the conventional resistance measurement method, when 1 ohm is used as the resistance and 750 mA, which is the power of a standard streetlight module (25 W), flows, 0.75 V is generated between both ends of the resistor and the power consumption is 0.56 mW ( P=IV) occurs. A loss of 2.25W (+α) occurs in a 100W street light (25W * 4EA).

Therefore, the problem of conventional lighting devices is that their overall efficiency is lowered to 2.3% or more.

Here, power loss can be minimized by using a low resistance value (several ohms), but a large measurement error occurs. To solve this problem, using a voltage amplifier IC in the secondary stage reduces power consumption and price by configuring additional components. There is this rising problem.

In other words, conventional lighting devices use a monitoring method using resistance, and the power loss may increase due to the use of OPAmp, MCU, etc.

KR 10-1753193 B1(2017.06.27)

The present invention was created to solve the above-described conventional problems, and the purpose of the present invention is to provide a monitoring system for lighting that can minimize power loss.

Therefore, the present invention includes the following embodiments to achieve the above object.

An embodiment of the present invention includes a lighting unit each having a plurality of lighting modules, a power supply unit supplying power to the plurality of lighting modules, and a monitoring unit measuring the current of each lighting module, and the monitoring unit is connected to the output side of the lighting module. A lighting monitoring system can be provided that includes a switching element equipped with a parasitic element and a controller that measures the current value that conducts the parasitic element by selectively turning off the switching element in the on state of the lighting module.

The present invention was created to solve the above-described conventional problems. The purpose of the present invention is to minimize power consumption by turning on the switching element when the current is not being monitored, and to turn the switching element off when measuring the current. We provide a lighting monitoring system that can measure and monitor current through internal parasitic elements.

Figure 1 is a circuit diagram showing the prior art.
Figure 2 is a block diagram showing the present invention.
Figure 3 is a block diagram showing the monitoring unit of the present invention.
Figure 4 is a circuit diagram showing one embodiment of the sensing means of the present invention.
5 to 7 are diagrams for explaining the operation of the sensing means.
Figure 8 is a circuit diagram showing another embodiment of the sensing means.
Figure 9 is a graph showing IV characteristics of another example.
10 and 11 are circuit diagrams and characteristic curves briefly showing another embodiment of the present invention.
Figure 12 is a circuit diagram showing another embodiment of the present invention.

Although the present invention may be subject to various changes and may have various embodiments, specific embodiments will be described in detail by illustrating them in the drawings. This is not intended to limit the present invention to specific embodiments, and is not intended to limit the present invention to any of the changes, equivalents, or substitutes included in the spirit and scope of the present invention for connecting and/or fixing structures extending in different directions. It must be understood as applicable.

The terms used herein are only used to describe specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly dictates otherwise.

In this specification, terms such as “comprise” or “have” are intended to indicate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, but are not intended to indicate the presence of one or more other features. It should be understood that it does not exclude in advance the existence or possibility of addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

Hereinafter, a preferred embodiment of the lighting monitoring system according to the present invention will be described in detail with reference to the attached drawings.

Figure 2 is a block diagram showing the present invention, and Figure 3 is a block diagram showing a monitoring unit of the present invention.

2 and 3, the present invention includes a power supply unit 100, a monitoring unit 200, a lighting unit 300, and a dimming controller 210.

The power unit 100 supplies power to the lighting unit 300 by the dimming controller 210 and/or the monitoring unit 200.

The lighting unit 300 includes a plurality of lighting modules 310, 320, and 330 that emit light by power supplied from the power supply unit 100. Here, each lighting module (310, 320, 330) includes a plurality of lighting means (eg, LED) connected in series. Additionally, the lighting modules 310, 320, and 330 are connected in parallel to each other.

The monitoring unit 200 monitors the lighting modules 310, 320, and 330. For example, the monitoring unit 200 is connected to the output side of each lighting module 310, 320, and 330 and measures current. Here, the monitoring unit 200 outputs the detected result to the dimming controller 210 or directly controls the power supply unit 100 (for example, adjusts the supply power in proportion to the number of failed lighting modules 310, 320, and 330). can be adjusted).

To this end, the monitoring unit 200 includes a detection means 240 that measures the power for each lighting module 310, 320, and 330, a constant voltage output means 230 that outputs a constant voltage, and a detection result of the detection means 240. It includes a controller 210 that receives and calculates a current value, and a switching means 220 that switches power to the sensing means 240.

The detection means 240 detects the power of each lighting module 310, 320, and 330 and outputs the power to the controller 210.

The constant voltage output means 230 converts the power output from the power supply unit 100 into constant voltage and supplies it to the detection means 240.

The controller 210 detects a failure by receiving a detection signal from the detection means 240. One embodiment of the sensing means 240 will be described with reference to FIGS. 4 to 7.

Figure 4 is a circuit diagram showing one embodiment of the sensing means of the present invention.

Referring to FIG. 4, in one embodiment of the present invention, the sensing means 240 is a first sensor on the output side of a plurality of lighting modules 310, 320, and 330 in which a plurality of lighting means (for example, LEDs) are connected in series. It includes a first switching element (Q1) having a terminal and a second terminal connected, a gate connected to the controller 210, and a first parasitic element (BD1) connected between the first terminal and the second terminal.

Here, the gate of the first switching element Q1 is connected to the output side of the constant voltage output means 230. At this time, the control signal line CV connected to the gate may be turned on and off by the switching operation of the switching means 220 connected between the constant voltage output means 230 and the gate. At this time, the switching means 220 is turned on and off by the controller 210.

Accordingly, the first switching element Q1 can be turned on or off under the control of the controller 210. For example, the first switching element Q1 is turned on when the current is not being monitored, and is turned off when the current is being monitored.

The first terminal is, for example, connected to the output side of the lighting modules 310, 320, and 330, and the second terminal is connected to the ground terminal.

The first parasitic element BD1, for example, is a diode and is connected to the first terminal on the input side and the second terminal on the output side.

At this time, the detection signal line DS of the controller 210 is connected to the input side of the first parasitic element BD1 and the first terminal.

Therefore, when the controller 210 turns on the first switching element Q1, electricity is passed between the first terminal and the second terminal, as shown in FIG. 5. At this time, the turn-on resistance is almost zero, so the power consumption is also close to O.

Alternatively, when the controller 210 turns off the first switching element (Q1), the current of the lighting modules (310, 320, 330) turns on the first parasitic element (BD1) as the space between the first and second terminals is blocked. It is output through.

Here, the first parasitic element BD1 may be a diode (eg, Schottky diode). Therefore, the controller 210 can measure the current using a change in VF (Voltage Forward) proportional to the current, as shown in the diode characteristic curve shown in FIG. 7.

If the controller 210 fails, the first switching element Q1 is turned off because power is not input to the gate. However, even if the first switching element (Q1) remains in the off state, the lighting module can maintain the lighting state as current flows through the first parasitic element (BD1).

Here, the first switching element Q1 may be a FET connected in the reverse direction, and the first parasitic element BD1 may be connected in the forward direction from the FET connected in the reverse direction.

Therefore, when the first switching element Q1 is a FET with a low drain-source voltage, a turn-on resistance close to O can be selected, so no power loss will occur.

That is, in one embodiment of the present invention, when turning off the first switching element (Q1) equipped with the first parasitic element (BD1), the current value is changed through a change in the forward voltage flowing through the first parasitic element (BD1). It is to measure.

Additionally, the controller 210 outputs the calculated current measurement result to the power supply unit and/or the dimming controller 400.

Accordingly, the power unit 100 and/or the dimming controller 400 can selectively control each lighting module to turn on or off, adjust brightness, etc., according to the current value calculated by the controller 210.

The present invention includes other embodiments, which are described with reference to FIGS. 8 and 9.

FIG. 8 is a circuit diagram showing another embodiment of the sensing means, and FIG. 9 is a graph showing IV characteristics of another embodiment.

Referring to FIG. 8, in another embodiment of the present invention, the sensing means 240 includes a second switching element Q2 provided with a second parasitic element BD2 and a sensing resistor Rd.

The second switching element (Q2) is installed on the output side of the lighting modules (310, 320, 330), and the gate is connected to the switching means (220) that is turned on and off by the controller (210).

The second parasitic element BD2 may be a Schottky diode connected in the reverse direction. For example, the Schottky diode has a second terminal of the second switching element (Q2) whose output side is connected to the output side of the lighting modules (310, 320, 330), and a second switching element (Q2) whose input side is connected to the ground terminal. ) is connected to the first terminal of

The sensing resistor (Rd) is connected in parallel with the second switching element (Q2). That is, the sensing resistor Rd is connected between the output side of the lighting modules 310, 320, and 330 and the ground terminal.

The controller 210 is connected to a detection signal line DS extending from the input side of the second switching element Q2.

When the switching means is turned on under the control of the controller 210, the second switching element Q2 is turned on by receiving a constant voltage from the constant voltage output means 230 on the gate side. At this time, the current output from the lighting modules 310, 320, and 330 passes through the second switching element Q2.

Alternatively, the second switching element Q2 is turned off under the control of the controller 210. At this time, the current of the lighting modules 310, 320, and 330 is passed through the sensing resistor Rd as the second parasitic element is connected in the reverse direction. Therefore, the voltage applied across the resistor is input to the controller 210 through the detection signal line DS.

Therefore, the controller 210 can calculate the current value according to the voltage-to-current characteristics as shown in FIG. 9.

Figure 10 is a circuit diagram showing another embodiment of the present invention, and Figure 11 is a VF characteristic curve of a diode depending on the amount of current.

Referring to the drawings, another embodiment of the present invention includes a third switching element (Q3) provided with a third parasitic element (BD3) connected in the reverse direction, unlike the second parasitic element (BD2) of the previously described embodiment. 3 It includes a sensing resistor (Rd) connected in parallel with the switching element (Q3).

The third parasitic element BD3 is connected in the forward direction between the first and second terminals of the third switching element Q3.

Here, the detection signal line is connected to the controller 210 between the third switching element (Q3) and the output side of the lighting modules (310, 320, 330), and the switching means 220 is connected to the gate of the third switching element (Q3). connected. Here, the third parasitic element BD3 may be a Schottky diode.

For example, the third switching element Q3 is turned on or off according to the switching of the switching means 220. If the third switching element Q3 is turned off, the controller 210 can measure a linear current value within 0.7V at both ends of the sensing resistor Rd, as shown in the diode VF characteristic curve of FIG. 11.

Figure 12 is a circuit diagram showing another embodiment of the present invention.

Referring to FIG. 12, another embodiment of the present invention includes a fourth switching element (Q4) equipped with a fourth parasitic element (BD4) and an external diode (D1).

The fourth parasitic element, for example, is a diode and, unlike the third parasitic element BD3, is connected in the reverse direction. That is, the output side of the fourth parasitic element BD4 is connected to the lighting modules 310, 320, and 330, and the input side is connected to the ground terminal.

The external diode (D1) is a diode connected in parallel with the fourth switching element (Q4) and is connected in the forward direction.

Here, the fourth parasitic element BD4 and the external diode D1 have different characteristics.

That is, another embodiment of the present invention measures the current by adding an external diode D1 having the original target characteristics when the fourth parasitic element BD4 has different characteristics from the original target characteristics.

In the above, preferred embodiments of the present invention have been shown and described, but the present invention is not limited to the specific embodiments described above, and may be used in the technical field to which the invention pertains without departing from the gist of the invention as claimed in the claims. Of course, various modifications can be made by those skilled in the art, and these modifications should not be understood individually from the technical idea or perspective of the present invention.

100: power unit
200: monitoring unit
210: controller
220: switching means
230: constant voltage output means
240: detection means
300: lighting unit
400: Dimming controller

Claims (7)

A lighting unit 300 each including a plurality of lighting modules 310, 320, and 330;
A power supply unit 100 that supplies power to a plurality of lighting modules 310, 320, and 330; and
A monitoring unit 200 that measures the current of each of the lighting modules 310, 320, and 330; Including,
The monitoring unit 200 is
A switching element provided with a parasitic element connected to the output side of the lighting module (310, 320, 330); and
A controller 210 that measures the current value of the parasitic element by selectively turning off the switching element in the on state of the lighting modules 310, 320, and 330; Including,
The monitoring unit 200 is
A sensing resistor connected in parallel with the switching element; A monitoring system for lighting that further includes.
delete In claim 1, the monitoring unit 200 is
An external diode (D1) connected in parallel with the switching element; A monitoring system for lighting, characterized in that it further includes.
The method of claim 1, wherein the parasitic element is
One that is a Schottky diode connected in the forward direction; A monitoring system for lighting characterized by .
The method of claim 1, wherein the parasitic element is
One that is a Schottky diode connected in reverse direction; A monitoring system for lighting characterized by .
The method of claim 1, wherein the parasitic element is
A monitoring system for lighting characterized by a diode connected in the reverse direction.
The method according to claim 1, wherein the parasitic element is a diode connected in the forward direction; A monitoring system for lighting, characterized in that.

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