KR20190012940A - Flicker Prevention LED Lightening Device - Google Patents

Abstract

The present invention relates to a flicker-prevented LED lighting device and, more specifically, to a flicker-prevented LED lighting device which is driven by receiving an input from an AC power supply, prevents an LED flicker by eliminating the ripple current, prevents the flickering when a lighting is turned off, and provides broadcast lighting which can be maintained even when the AC power or an LED fails.

Description

[0001] Flicker Prevention LED Lightening Device [

The present invention relates to an LED lighting device which is prevented from flickering, and more particularly, to an LED lighting device which is driven by receiving an AC power source and which prevents flickering of an LED by eliminating a ripple current, And more particularly, to an LED lighting device which can provide a broadcast illumination capable of maintaining illumination even in the event of an abnormality of the LED, which is prevented from blinking.

Generally, the LED lighting device is configured to adjust the brightness by changing the supplied current based on a constant voltage, or by using a current control method for detecting a current and flowing a constant current, And is widely used as a device.

The power supply circuit in LED lighting equipment is difficult to realize a perfect direct current, and the ripple component (120Hz) operates in the form of DC.

Normally, even if such a ripple component is more than 15% of the total DC level, it does not feel the afterglow effect of a human eye, but a sensitive person senses the flicker. Flicker is a flicker of the direct light level, . Since flicker is recognized through a digital camera or the like in this way, it is necessary to suppress the occurrence of flicker in the case of illumination used for broadcasting and the like.

An object of the present invention is to provide a lighting system capable of preventing flickering of an LED by eliminating a ripple current, preventing flicker when the lighting is turned off, broadcasting light for maintaining illumination even when an AC power source or an LED fails, So as to prevent flickering that can be provided.

According to an aspect of the present invention, there is provided an LED lighting device for preventing blinking, the LED lighting device comprising: an LED unit including one or more LEDs to provide illumination according to control; An AC power supply unit for supplying AC power; A rectifying unit for converting AC power into DC power; A DC / DC converter for adjusting a driving voltage of the DC power supply; An LED control unit for controlling the LED units to be turned on and off, and controlling illumination; A ripple removing unit disposed between the DC / DC converter and the LED unit to remove a ripple current of the power source; And a flickering prevention unit for preventing a flicker generated when the LED illumination is turned off; And an LED lighting device.

In the present invention, the ripple removing unit may include at least one electrolytic capacitor filter for smoothing the driving voltage and removing a ripple component from current components flowing through the LED unit.

In the present invention, the flicker prevention portion may include: a first resistor and a second resistor connected to the junction of the LED portion and the ripple removing portion; A first switching element which is formed between the second resistor and the ground terminal and is turned on or off by receiving a control signal from the first resistor; And a second switching element which is formed between the first resistor and the ground terminal and is turned on or off by receiving a control signal of the LED controller; . ≪ / RTI >

In the present invention, the LED unit may include an LED module including one or a plurality of LEDs, A spare LED module composed of one or a plurality of LEDs and adapted to emit light when powered on; And an LED management unit for applying power to the LED module according to a control signal of the LED control unit, determining whether the LED module is operating normally, and applying power to the spare LED module when the LED module does not operate normally; . ≪ / RTI >

In the present invention, the LED management unit may include: an LED module control unit for applying power to the LED module according to a control signal of the LED control unit; An LED module monitoring unit for determining whether the LED module is operating normally; And a spare LED module controller for applying power to the spare LED module when the LED module does not operate normally; . ≪ / RTI >

In the present invention, the LED unit may include two or more LED modules, and the LED management unit may apply power to the spare LED module when any one of the two or more LED modules does not operate normally.

In the present invention, the LED control unit may include: a first LED control unit that receives illumination of the illumination and controls power supplied to the LED module; And a second LED controller for controlling a current supplied to the LED module under the control of the first LED controller; Wherein the first LED control unit comprises: an illuminance input unit for receiving illuminance of the LED illumination; And a control panel unit for determining whether the input illuminance is equal to or greater than a preset threshold illuminance. Wherein the second LED controller comprises: a PWM controller for controlling the illuminance of the LED unit by a PWM method when the input illuminance is less than a predetermined threshold illuminance; And a DC control unit for controlling the illuminance of the LED unit using a DC control method when the input illuminance is equal to or greater than a predetermined threshold illuminance; . ≪ / RTI >

In the present invention, the PWM control unit can control the illuminance of the LED unit by adjusting the duty ratio based on the input illuminance while maintaining a constant voltage supplied to the LED unit.

In the present invention, the DC control unit may control the illuminance of the LED unit by adjusting a voltage supplied to the LED unit based on the input illuminance.

In the present invention, the LED lighting device may include an auxiliary power source capable of supplying power to the LED lighting device; The LED control unit may receive power from the auxiliary power unit and control the LED lighting when the power is not supplied from the AC power source unit.

According to an embodiment of the present invention, it is possible to suppress the occurrence of flicker in an LED illumination that is driven by receiving an AC voltage.

According to an embodiment of the present invention, it is possible to prevent flicker that may occur when the LED illumination is turned off.

According to the embodiment of the present invention, when the illuminance of the LED illumination is controlled by the PWM method in the case of less than the critical illuminance and by the DC control method in the case of the illuminance of the threshold illuminance or more, it is possible to perform the accurate illuminance control while suppressing flickering or flickering .

According to an embodiment of the present invention, even when an abnormality occurs in the LED module, it is possible to provide continuous illumination by driving the spare LED module.

According to an embodiment of the present invention, even when an abnormality occurs in the AC power source unit, power can be supplied from the auxiliary power source unit to provide continuous illumination.

1 is a circuit diagram schematically showing a circuit of a direct-coupled type LED lighting which is driven by receiving an AC power source.
2 is a graph schematically showing the VI characteristic and the dynamic resistance of the LED.
3 is a graph schematically showing the relationship between voltage and current in an LED illumination driven by an AC power source.
FIG. 4 is a graph schematically showing a change in voltage when the LED lighting apparatus including a ripple removing unit using a capacitor is turned off.
5 is a block diagram schematically showing a configuration of an LED lighting apparatus according to an embodiment of the present invention.
6 is a view schematically showing a configuration of an LED lighting apparatus according to an embodiment of the present invention.
7 is a view schematically showing a configuration of an LED unit according to an embodiment of the present invention.
8 is a block diagram schematically showing the internal configuration of an LED management unit according to an embodiment of the present invention.
9 is a block diagram schematically showing a configuration of an LED lighting apparatus according to another embodiment of the present invention.
10 is a block diagram schematically illustrating an internal configuration of an LED control unit according to an embodiment of the present invention.
11 is a graph schematically showing control values according to illumination control of an LED illumination according to an embodiment of the present invention.
12 is a block diagram schematically showing a configuration of an LED lighting apparatus according to another embodiment of the present invention.

In the following, various embodiments and / or aspects are now described with reference to the drawings. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more aspects. However, it will also be appreciated by those of ordinary skill in the art that such aspect (s) may be practiced without these specific details. The following description and the annexed drawings set forth in detail certain illustrative aspects of one or more aspects. It is to be understood, however, that such aspects are illustrative and that some of the various ways of practicing various aspects of the principles of various aspects may be utilized, and that the description set forth is intended to include all such aspects and their equivalents.

In addition, various aspects and features will be presented by a system that may include multiple devices, components and / or modules, and so forth. It should be understood that the various systems may include additional devices, components and / or modules, etc., and / or may not include all of the devices, components, modules, etc. discussed in connection with the drawings Must be understood and understood.

As used herein, the terms "an embodiment," "an embodiment," " an embodiment, "" an embodiment ", etc. are intended to indicate that any aspect or design described is better or worse than other aspects or designs. . The terms 'component', 'module', 'system', 'interface', etc. used in the following generally refer to a computer-related entity, And a combination of software and software.

It is also to be understood that the term " comprises "and / or" comprising " means that the feature and / or component is present, but does not exclude the presence or addition of one or more other features, components and / It should be understood that it does not.

Also, terms including ordinal numbers such as first, second, etc. may be used to describe various elements, but the elements are not limited to these terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component. And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

Furthermore, in the embodiments of the present invention, all terms used herein, including technical or scientific terms, unless otherwise defined, are intended to be inclusive in a manner that is generally understood by those of ordinary skill in the art to which this invention belongs. Have the same meaning. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and, unless explicitly defined in the embodiments of the present invention, are intended to mean ideal or overly formal .

1 is a circuit diagram schematically showing a circuit of a direct-coupled type LED lighting which is driven by receiving an AC power source.

Referring to FIG. 1A, a direct-coupled LED lighting apparatus for driving an AC power source receives AC power, includes an AC power source 10 for supplying AC power, a rectifier 20 for converting AC power to DC, Consists of.

As shown in FIG. 1 (A), the rectifying unit 20 composed of the bridge diode BD receives the AC power from the AC power supply unit 10 and converts it to DC. At this time, the LED 30 generates a flicker corresponding to twice the commercial voltage frequency according to the fluctuation of the full-wave rectified voltage provided from the bridge diode BD, and the dynamic resistance of the LED 30, A period in which the LED 30 does not light up occurs, and the overall brightness variation is periodically repeated. This flicker is not discriminated by the naked eye but affects the image quality of the image when it is used as illumination for industrial illumination or image processing system and also reduces the luminous efficiency of the LED 30.

As a countermeasure thereto, the flicker phenomenon can be improved by connecting the capacitor 40 in parallel with the LED 30 as shown in FIG. 1 (B).

2 is a graph schematically showing the V-I characteristic and the dynamic resistance of the LED.

The LED converts the current according to the voltage applied in the forward direction to light based on a single PN junction. The LED is a depletion layer of the PN junction, through which holes and free electrons can pass. When a voltage of 0.6 to 0.7 V or more is applied to the LED, a current begins to flow. Depending on the voltage applied to the PN junction, . Referring to the dotted line graph on the left side of FIG. 2, the dynamic resistance of the diode has a very large resistance value because the slope of the tangent line to the VI characteristic curve is close to horizontal in the vicinity of Vf1. As the applied voltage increases And the dynamic resistance is reduced because of the close proximity to the vertical direction. The solid line graph on the right side of FIG. 2 is an example of the V-I characteristics of an ordinary LED for illumination, in which a forward voltage Vfn has a relatively large value as compared with a single-junction LED since a plurality of LEDs are connected in series. For example, for an AC 220 V 50 Watt illumination LED, 84 LEDs are connected in series, so the forward voltage Vfn is 0.6 V X 84 ≒ 50 V. Therefore, when the voltage applied to the AC 220 V 50 Watt illumination LED is 50 V or less, the illumination LED does not turn on as a cutoff state despite the forward bias.

3 is a graph schematically showing the relationship between voltage and current in an LED illumination driven by an AC power source.

Referring to FIG. 3, the relationship of the voltage and current to the basic configuration of the direct-current LED lighting device of the AC power source can be confirmed. When a full-wave rectified voltage is supplied to the LED array in an AC power direct-coupled LED lighting device, a flicker (flicker) corresponding to twice the commercial voltage frequency occurs. Also, as described in FIG. 2, The dynamic resistance causes the LED array to be in an unlighted section, so that the overall brightness variation is periodically repeated. 3 (A) shows the current IL with respect to the forward voltage Vf of the LED array when the full-wave rectified voltage V is provided to the LED array. In the direct-coupled LED drive circuit, the current IL of the LED array begins to flow due to the dynamic resistance due to the influence of the dynamic resistance near the forward voltage Vf and starts to flow at a phase angle equal to or larger than the forward voltage Vf. It can be seen that a section d in which the array is not lit occurs. 1 (B), when the capacitor is connected in parallel with the LED array, the current IL of the LED array is supplied to the direct current type LED lighting device by the charge / The ripple is removed, and the flicker phenomenon and the section where the LED array is not lit can be removed.

FIG. 4 is a graph schematically showing a voltage change when the LED lighting apparatus including the ripple removing unit 500 using a capacitor is turned off.

As described above, when the ripple removing unit 500 is formed by connecting the capacitor to the direct LED lighting device, it is possible to eliminate flicker by removing the ripple.

When the LED lighting circuit to which the capacitor is connected is turned off, the charge charged in the capacitor is discharged, so that the voltage applied to the LED gradually decreases. When the LED is not connected to the capacitor, the voltage gradually decreases with time as shown by the dotted line graph of FIG.

However, when the capacitor and the LED are connected, when the voltage applied to the LED decreases and reaches Vf of the LED (t1), the current is cut off due to the characteristics of the diode, and the voltage applied to the LED increases instantaneously as the load disappears t2). As the voltage increases momentarily, the LED flickers. Such a flicker is not a problem in general lighting, but in the case of a broadcast light using a camera or the like, a minute flicker may affect a shooting object, and therefore it is necessary to prevent such blinking.

5 is a block diagram schematically showing a configuration of an LED lighting apparatus according to an embodiment of the present invention.

5, an LED lighting apparatus according to an exemplary embodiment of the present invention includes an AC power source 100, a rectifier 200, a DC / DC converter 300, an LED controller 400, a ripple removal unit 500, Prevention unit 600 and an LED unit 700. [

The AC power supply unit 100 supplies AC power. According to an embodiment of the present invention, the AC power source 100 may receive an AC power through an external socket or the like and supply the AC power to the LED lighting device.

The rectifier 200 converts the AC power to DC power. According to an embodiment of the present invention, the rectifier 200 may include a bridge diode or the like and convert the AC power inputted thereto into rectified and rectified to DC power.

The DC / DC converter 300 regulates the driving voltage of the DC power source. According to an embodiment of the present invention, the DC / DC converter 300 includes a linear regulator or a switching regulator and regulates the voltage of the DC power source to be suitable for the driving circuit.

The LED control unit 400 controls the LED unit 700 to be turned on, off, and illuminated. The LED controller 400 controls the LED unit 700 by controlling the power supplied to the LED unit 700. According to an embodiment of the present invention, the LED controller 400 controls the amount of current supplied to the LED unit 700, thereby controlling the ON / OFF and illumination of the LED unit 700.

The ripple removal unit 500 is disposed between the DC / DC converter and the LED unit to remove the ripple current of the power source. The ripple removal unit 500 according to an embodiment of the present invention may include one or more capacitor filters to remove the ripple current of the power supply.

The flickering prevention unit 600 prevents flicker caused when the LED lighting is turned off. The flickering prevention unit 600 prevents a flicker that may occur instantaneously when the LED lighting is turned off when a circuit including a capacitor is constructed as described with reference to FIG. The flicker prevention unit 600 according to an embodiment of the present invention includes a switching device that operates by receiving the ON and OFF signals of the LED control unit 400 so as to bypass the LED unit 700 when the LED lighting unit is turned off, It is possible to prevent the flicker generated when the LED lighting is turned off.

The LED unit 700 is composed of one or more LEDs and is illuminated according to the control. The LED unit may include an LED cluster composed of a plurality of LEDs according to the purpose of the LED illumination, and may provide illumination by receiving a voltage.

6 is a view schematically showing a configuration of an LED lighting apparatus according to an embodiment of the present invention.

Referring to FIG. 6, a circuit diagram of a part of the LED lighting apparatus according to an embodiment of the present invention can be confirmed.

The rectifier 200 according to an embodiment of the present invention may be formed of a bridge diode BD as shown in FIG. When the AC power source is rectified through the bridge diode as described above, flicker may occur as described with reference to FIG. 1, so flicker must be prevented through the ripple removing unit 500 or the like.

6, the ripple removing unit 500 may include at least one electrolytic capacitor filter for smoothing the driving voltage and removing the ripple component from the current components flowing in the LED unit 700 have.

6, the flicker prevention unit 600 includes a first resistor R1 and a second resistor R2 connected to a contact point of the LED unit 700 and the ripple removing unit 500, A first switching device Q1 formed between the second resistor R2 and the ground and receiving a control signal from the first resistor R1 to turn on or off and a first switching device Q1 connected between the first resistor R1 and the ground, And a second switching device Q2 configured to receive the control signal of the LED control unit 400 and turned on or off.

The operation of the flickering prevention unit 600 according to an embodiment of the present invention is as follows.

When a voltage is applied to the LED unit 700 by the LED control unit 400 and is turned on, a high signal is input to the base of the second switching device Q2 composed of an NPN transistor to allow a current to flow from the collector to the emitter do.

At this time, a first resistor R1 is connected between the collector of the second switching device Q2 and the driving power source. Since the collector of the second switching device Q2 is connected to the base of the first switching device Q1 composed of NPN transistors, when the collector current flows through the second switching device Q2, the collector of the first switching device Q1 A low signal is input to the base to cut off the collector current.

Therefore, in this case, only the channel from the driving power source through the first resistor R1 is connected to the ground point. At this time, since the resistance value of the first resistor R1 has a relatively large value, the power consumed through the flickering prevention part 600 is insignificant.

At this time, when the LED control unit 400 cuts off the voltage to the LED unit 700, the charge charged in the capacitor of the ripple removal unit 500 is discharged, and a weak current flows to the LED unit 700 do.

When it is turned off by the LED control unit 400, a Low signal is input to the base of the second switching device Q2, and the collector current is cut off. Therefore, a high signal is input to the base of the first switching device Q1 connected to the collector of the second switching device Q2, and a collector current flows through the first switching device Q1.

Therefore, since the flicker prevention unit 600 is connected from the driving power source to the ground via the second resistor R2 and the resistance value of the second resistor R2 is relatively small, The charge charged in the capacitor of the removal part 500 is discharged through the anti-flickering part 600, not the LED part 700, so that the LED part 700 can be prevented from blinking.

Referring to FIG. 6, the LED unit 700 according to an exemplary embodiment of the present invention may include a plurality of light emitting diodes connected in series or in parallel to form one cluster.

7 is a view schematically showing a configuration of an LED unit 700 according to an embodiment of the present invention.

Referring to FIG. 7, the LED unit 700 according to an embodiment of the present invention includes LED modules 720 to 740 which are composed of one or a plurality of LEDs and emit light when power is applied thereto, And a power supply to the LED modules 720 to 740 according to a control signal of the LED controller to determine whether the LED modules 720 to 740 are operating normally, And an LED management unit 710 for applying power to the spare LED module 750 when the modules 720 to 740 do not operate normally.

7, the LED unit 700 includes three LED modules and one spare LED module. However, the present invention is not limited thereto. The LED module 700 may include one or more LED modules and one or more spare LED modules .

The LED management unit 710 controls the illumination of the LED modules 720 to 740 and the spare LED module 750 by applying power to the LED modules 720 to 740 and the spare LED module 750. At this time, the LED management unit 710 applies power to the LED modules 720 to 740 in a normal state to control the LED modules 720 to 740 to provide illumination.

If the LED modules 720 to 740 do not operate normally, the LED management unit 710 applies power to the spare LED module 750 so that the LED modules 720 to 740 can operate in place of the LED modules 720 to 740.

7, the LED unit 700 according to an exemplary embodiment of the present invention may include two or more LED modules 720 to 740, and the LED management unit 710 may include two or more LED modules 720, 740 are not operated normally, the power is supplied to the spare LED module 750 so that the illumination can be continuously operated. If only one LED module among the plurality of LED modules 720 to 740 does not operate normally, the spare LED module 750 may be operated in place of the corresponding LED module that does not operate normally.

8 is a block diagram schematically showing the internal configuration of an LED management unit according to an embodiment of the present invention.

Referring to FIG. 8, the LED management unit 710 includes an LED module control unit 711, an LED module monitoring unit 712, and a spare LED module control unit 713.

The LED module controller 711 applies power to the LED modules 720 to 740 according to a control signal of the LED controller 400. According to an embodiment of the present invention, the LED module control unit 711 may independently control power by applying power to the plurality of LED modules 720 to 740. If the LED modules 720 to 740 are independently controlled as described above, if any one of the LED modules does not operate normally, only the corresponding LED module can be powered off and other LED modules can be continuously operated.

The LED module monitoring unit 712 determines whether the LED modules 720 to 740 are operating normally. The LED module monitoring unit 712 monitors the operation of the LED modules 720 to 740 through various methods and determines whether the LED modules 720 to 740 operate according to the control of the LED control unit 400 I understand.

The spare LED module controller 713 applies power to the spare LED module 750 when the LED modules 720 to 740 do not operate normally. The preliminary LED module control unit 713 receives the monitoring result of the LED module monitoring unit 712 for this purpose and applies power to the preliminary LED module 750 when an abnormality is found, To operate.

Preferably, the LED management unit further includes an LED abnormality notification unit (not shown) for displaying the LED abnormality to the user when the LED modules 720 to 740 do not operate normally, so that the LED modules 720 to 740 do not operate normally When replacing the spare LED module 750 with the spare LED module 750, the user can identify the abnormality of the LED module and take measures such as replacing the LED module in which the abnormality occurs. The LED abnormality notification unit (not shown) may display an abnormality to the user himself or may transmit an abnormality to the LED control unit 400 so that the LED control unit may display an abnormality to the user.

In this manner, when any one of the LED modules 720 to 740 does not operate normally, the LED management unit 710 can supply power to the spare LED module 750 to operate in place of the LED module that does not operate normally, It is possible to continuously supply illumination without causing a problem such as a change in illuminance of illumination even when an abnormality occurs in the modules 720 to 740 and to display the LED module to the user so that the user can replace the LED module .

9 is a block diagram schematically showing a configuration of an LED lighting apparatus according to another embodiment of the present invention.

9, an LED lighting apparatus according to another embodiment of the present invention includes an AC power source unit 100, a rectifier unit 200, a DC / DC converter 300, a first LED control unit 410, a second LED control unit 420, A ripple removal unit 500, a flickering prevention unit 600, and an LED unit 700.

5, the AC power source unit 100, the rectifier unit 200, the DC / DC converter 300, the ripple removal unit 500, the flickering prevention unit 600 and the LED unit 700 are the same as those shown in FIG. Is omitted.

The first LED controller 410 receives the illuminance of the illumination and controls the power supplied to the LED module. The first LED control unit 410 receives the illuminance of the illumination while performing the same function as the LED control unit 400 shown in FIG. 5, and controls power supplied to the LED module based on the received illuminance, . The first LED control unit 410 may transmit a control signal to the AC power source unit 100, the rectifier unit 200, or the DC / DC converter 300.

In this case, the first LED controller 410 may determine whether the received illuminance is equal to or greater than a predetermined threshold illuminance, and may select and control the illuminance control method according to the illuminance.

The second LED control unit 420 controls the current supplied to the LED module under the control of the first LED control unit 410. The second LED controller 420 controls the illuminance of the LED module by controlling the current supplied to the LED module according to the illumination control method selected by the first LED controller 410. For this, the second LED control unit 420 may be configured to directly control a current supplied to the LED unit 700. FIG.

The second LED control unit 420 may be connected to the first LED control unit to receive a control signal to be controlled by the first LED control unit 410.

10 is a block diagram schematically illustrating an internal configuration of an LED control unit according to an embodiment of the present invention.

10, an LED controller 400 according to an exemplary embodiment of the present invention includes a first LED controller 410 and a second LED controller 42. The first LED controller 410 includes an illuminance input unit 411, And a control panel end 412. The second LED control unit 420 includes a PWM control unit 421 and a DC control unit 422. [

The LED control unit 400 according to an embodiment of the present invention not only controls the lighting and lighting of the LED lighting, but also controls the illumination.

In this case, the LED controller 400 controls the illuminance of the LED unit 700 using a DC control method when the illuminance control value is equal to or greater than a preset threshold illuminance, and when the illuminance control value is less than the threshold illuminance, Thereby controlling the illuminance of the display device 700.

The illuminance input unit 411 receives illuminance of the LED illumination. The illuminance input unit 411 can receive the illuminance in an analog or digital manner. When the illuminance input is 0, the illuminance input unit 411 recognizes the illuminance as off and can perform the off-light control.

The control panel end 412 determines whether the input illuminance is equal to or greater than a predetermined threshold illuminance. The threshold illuminance may be preset and input by the characteristics of the LED unit 700 included in the LED lighting apparatus. When the input illuminance is less than the critical illuminance, the control unit 412 causes the PWM control unit 421 to control the illuminance, and when the input illuminance is equal to or higher than the threshold illuminance, the DC control unit 422, which will be described later, .

The PWM controller 421 controls the illuminance of the LED unit 700 by the PWM method when the input illuminance is less than a predetermined threshold illuminance. The PWM controller 421 controls the illuminance of the LED unit 700 by controlling the amount of current flowing to the LED unit 700 through the PWM signal of a constant voltage when the input illuminance is less than the critical illuminance.

More specifically, the PWM control unit 421 controls the illuminance of the LED unit 700 by adjusting the duty ratio based on the received illuminance while maintaining the voltage supplied to the LED unit 700 constant.

The DC control unit 422 controls the illuminance of the LED unit 700 by a DC control method when the input illuminance is equal to or greater than a predetermined threshold illuminance. The DC control unit 422 controls the illuminance of the LED unit 700 by controlling the amount of current flowing to the LED unit 700 by adjusting the voltage when the received illuminance is equal to or higher than the critical illuminance.

More specifically, the DC control unit 422 controls the illuminance of the LED unit 700 by adjusting a voltage supplied to the LED unit 700 based on the received roughness.

11 is a graph schematically showing control values according to illumination control of an LED illumination according to an embodiment of the present invention.

Referring to FIG. 11, the LED control unit 400 according to an exemplary embodiment of the present invention can check the voltage control value, the duty ratio, and the current amount with respect to the illumination control value, which is controlled when performing the illumination control.

11 (A), when the illuminance control value is higher than the critical illuminance X1, the voltage control value increases as the illuminance control value becomes higher, and the voltage control value becomes lower as the illuminance control value becomes lower. When the illuminance control value is lower than the critical illuminance X1, the voltage control value is kept constant as the voltage control value at the critical illuminance X1 irrespective of the illuminance control value.

11 (B), when the illuminance control value is lower than the threshold illuminance X1, the duty ratio is lowered. The higher the illuminance control value is, the higher the duty ratio is. The duty ratio at the critical illuminance X1 is 100%. Also, since the DC control is performed when the critical illuminance is X1 or more, the duty ratio is maintained at 100%.

11C, the LED controller 400 controls the current supplied to the LED unit 700 to be the luminance control value, as shown in FIG. 11C, by performing the PWM control when the threshold illuminance is less than X1 and the DC control when the threshold illuminance is X1 or more So as to control the illuminance of the LED illumination.

12 is a block diagram schematically showing a configuration of an LED lighting apparatus according to another embodiment of the present invention.

12, the LED lighting device according to another embodiment of the present invention includes an AC power source 100, a rectifier 200, a DC / DC converter 300, an LED controller 400, a ripple removal unit 500, A flicker prevention unit 600, an LED unit 700, and an auxiliary power unit 800.

5, the AC power source unit 100, the rectifier unit 200, the DC / DC converter 300, the ripple removal unit 500, the flickering prevention unit 600 and the LED unit 700 are the same as those shown in FIG. Is omitted.

The auxiliary power unit 800 may supply power to the LED lighting device. The auxiliary power unit 800 may be controlled by the LED controller if the LED lighting apparatus does not supply power during normal operation but fails to receive power due to an abnormality in the AC power unit 100 or the rectifier unit 200 Supply power to the LED lighting device. Preferably, the auxiliary power unit 800 includes a power source independent of the AC power unit 100 so that the auxiliary power unit 800 can operate even when an abnormality occurs in the AC power unit 100.

The auxiliary power unit 800 according to an embodiment of the present invention temporarily supplies power to the AC power unit 100 in case the power is not supplied from the AC power unit 100 so that the LED light can continuously provide illumination. Therefore, the auxiliary power supply unit 800 may temporarily supply power to the internal battery such as the AC power supply unit 100 without needing to receive the continuous power supply from the outside. In this case, DC power may be supplied instead of AC power.

If the auxiliary power unit 800 includes an AC power source, it is preferable that the LED unit 700 can receive a DC current by including a rectifier therein.

The LED control unit 400 is the same as that described above. When the power is not supplied from the AC power supply unit 100, the LED control unit 400 receives power from the auxiliary power supply unit 800 and controls the LED lighting.

The LED control unit 400 receives power from the AC power supply unit 100 and confirms whether the AC power supply unit 100 and the rectification unit 200 operate normally. If an abnormality is found as a result of the confirmation and the power is not supplied from the AC power source unit 100, the power is switched to be supplied from the auxiliary power unit.

The LED control unit 400 may further include an error notification unit (not shown) for notifying the user when power is supplied from the auxiliary power unit 800 because the power is not supplied from the AC power source unit 100, Allows the user to identify anomalies in the power supply and take action accordingly. More preferably, the abnormality notification unit receives the abnormality of the LED modules 720 to 740 of the LED unit 700 and displays it to the user so that the user can easily grasp the power supply or the abnormality of the LED module.

For this, the LED control unit 400 of the LED lighting apparatus according to an embodiment of the present invention includes a power supply monitoring unit (not shown) for determining whether power is supplied from the AC power supply unit 100 and a power supply monitoring unit And a power switch unit (not shown) that is supplied with power from the auxiliary power unit if it can not receive the power.

As described above, the LED lighting apparatus according to an embodiment of the present invention normally provides power by receiving power from an AC power source and supplies power from an auxiliary power source even when power is not supplied due to breakdown or disconnection of an AC power source It is possible to stably provide the illumination continuously regardless of the power source abnormality in the broadcasting using the LED illumination.

According to an embodiment of the present invention, it is possible to suppress the occurrence of flicker in an LED illumination that is driven by receiving an AC voltage.

According to an embodiment of the present invention, it is possible to prevent flicker that may occur when the LED illumination is turned off.

According to the embodiment of the present invention, when the illuminance of the LED illumination is controlled by the PWM method in the case of less than the critical illuminance and by the DC control method in the case of the illuminance of the threshold illuminance or more, it is possible to perform the accurate illuminance control while suppressing flickering or flickering .

According to an embodiment of the present invention, even when an abnormality occurs in the LED module, it is possible to provide continuous illumination by driving the spare LED module.

According to an embodiment of the present invention, even when an abnormality occurs in the AC power source unit, power can be supplied from the auxiliary power source unit to provide continuous illumination.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. For example, it is to be understood that the techniques described may be performed in a different order than the described methods, and / or that components of the described systems, structures, devices, circuits, Lt; / RTI > or equivalents, even if it is replaced or replaced. Therefore, other implementations, other embodiments, and equivalents to the claims are also within the scope of the following claims.

Claims (10)

CLAIMS 1. An LED lighting device,
An LED unit composed of one or more LEDs and providing illumination according to the control;
An AC power supply unit for supplying AC power;
A rectifying unit for converting AC power into DC power;
A DC / DC converter for adjusting a driving voltage of the DC power supply;
An LED control unit for controlling the LED units to be turned on and off, and controlling illumination;
A ripple removing unit disposed between the DC / DC converter and the LED unit to remove a ripple current of the power source; And
A flicker prevention unit for preventing a flicker generated when the LED lighting is turned off; And the LED illumination device.
The method according to claim 1,
Wherein the ripple-
And at least one electrolytic capacitor filter for smoothing the driving voltage and removing a ripple component from current components flowing through the LED portion.
The method of claim 2,
The flicker-
A first resistor and a second resistor connected to the junction of the ripple removal and the LED portion;
A first switching element which is formed between the second resistor and the ground terminal and is turned on or off by receiving a control signal from the first resistor; And
A second switching element which is formed between the first resistor and the ground terminal and is turned on or off in response to a control signal of the LED controller; And the LED illumination device.
The method according to claim 1,
The LED unit includes:
An LED module composed of one or a plurality of LEDs and adapted to emit light when powered on;
A spare LED module composed of one or a plurality of LEDs and adapted to emit light when powered on; And
An LED controller for applying power to the LED module according to a control signal of the LED controller to determine whether the LED module is operating normally and to apply power to the spare LED module when the LED module does not operate normally; And the LED illumination device.
The method of claim 4,
Wherein the LED management unit comprises:
An LED module controller for applying power to the LED module according to a control signal of the LED controller;
An LED module monitoring unit for determining whether the LED module is operating normally; And
A spare LED module controller for applying power to the spare LED module when the LED module does not operate normally; And the LED illumination device.
The method of claim 5,
Wherein the LED unit comprises two or more LED modules,
Wherein the LED management unit applies power to the spare LED module when any one of the two or more LED modules fails to operate normally.
The method according to claim 1,
Wherein the LED control unit comprises:
A first LED control unit receiving the illuminance of the illumination and controlling power supplied to the LED module; And
A second LED controller for controlling a current supplied to the LED module under the control of the first LED controller; Lt; / RTI >
The first LED control unit,
An illuminance input unit for inputting the illuminance of the LED illumination; And
A control panel unit for determining whether the input illuminance is greater than or equal to a predetermined threshold illuminance; Lt; / RTI >
The second LED control unit,
A PWM control unit for controlling the illuminance of the LED unit by a PWM method when the input illuminance is less than a predetermined threshold illuminance; And
A DC control unit for controlling the illuminance of the LED unit by a DC control method when the input illuminance is equal to or greater than a predetermined threshold illuminance; And the LED illumination device.
The method of claim 7,
Wherein the PWM control unit comprises:
Wherein the illuminance of the LED portion is controlled by adjusting the duty ratio based on the input illuminance while maintaining a constant voltage supplied to the LED portion.
The method of claim 7,
The DC control unit includes:
And controls the illuminance of the LED unit by adjusting a voltage supplied to the LED unit based on the input illuminance.
The method according to claim 1,
The LED lighting device includes:
An auxiliary power unit capable of supplying power to the LED lighting apparatus; Further comprising:
Wherein the LED control unit comprises:
Wherein the control unit controls the LED lighting by receiving power from the auxiliary power unit when the power is not supplied from the AC power source unit.

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