KR101435852B1 - System for lighting using light emitting diode - Google Patents

Abstract

FIELD OF THE INVENTION The present invention relates to illumination systems, and more particularly to illumination systems using light emitting diodes. According to the present invention, there is provided a rectifying device comprising: a rectifying part rectifying an AC power source and including a first terminal and a second terminal; A light emitting unit including a plurality of LEDs connected to the anode of the rectifying unit; A charging unit connected between the light emitting unit and the second terminal of the rectifying unit and having a charge path connected to the cathode of the light emitting unit and a discharge path connected to the anode of the light emitting unit; And a power controller for controlling the flow of current flowing through the charge / discharge unit.

Description

[0001] The present invention relates to a light emitting diode (LED)

FIELD OF THE INVENTION The present invention relates to illumination systems, and more particularly to illumination systems using light emitting diodes.

Recently, light emitting diodes (LEDs) having advantages such as efficiency, color diversity, and design autonomy have been attracting attention as a light source of illumination .

A light emitting diode is a semiconductor device which emits light when a voltage is applied in a forward direction, has a long lifetime, low power consumption, and has electrical, optical, and physical characteristics suitable for mass production.

In order to effectively use such a light emitting diode as a light source of illumination, a driving system capable of driving with a commercial AC power supply is required.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is an object of the present invention to provide an illumination system using a light emitting diode capable of solving the phenomenon such as flicker, power factor reduction, .

According to a first aspect of the present invention, there is provided a rectifying apparatus comprising: a rectifying unit rectifying an AC power source and including a first terminal and a second terminal; A light emitting unit including a plurality of LEDs connected to the anode of the rectifying unit; A charging unit connected between the light emitting unit and the second terminal of the rectifying unit and having a charge path connected to the cathode of the light emitting unit and a discharge path connected to the anode of the light emitting unit; And a power controller for controlling the flow of current flowing through the charge / discharge unit.

Here, the power control unit may include: a power control device connected to the light emitting unit; And a control circuit for controlling the power control element.

The control circuit controls the current to flow to the light emitting portion when the voltage passing through the rectifying portion is higher than the operating voltage of the light emitting portion and lower than the sum of the operating voltage and the charging / discharging portion.

When the voltage passing through the rectifying section is higher than the operating voltage of the light-emitting section plus the voltage of the charge-discharge section, the control circuit charges the charge-discharge section while a current flows through the light-emitting section.

The control circuit discharges the charge of the charging unit when the voltage passing through the rectifying unit is lower than the operating voltage of the light emitting unit.

According to a second aspect of the present invention, there is provided a light emitting diode illumination system comprising: a light emitting unit including a plurality of light emitting diodes connected in series; A rectifying unit for rectifying the AC power and supplying the pulsating voltage outputted to the light emitting unit; A charging unit connected to the light emitting unit; And a controller for controlling the current to flow to the light emitting unit when the magnitude of the pulsating current voltage satisfies the first condition and allowing current to flow to the light emitting unit when the magnitude of the pulsating voltage satisfies the second condition, And when the magnitude of the pulsating current voltage satisfies the third condition, discharges the charge of the charging unit to drive the light emitting unit.

The present invention has the following effects.

First, in an LED driving circuit using an AC power source that does not use an SMPS (Switching Mode Power Supply), it can be driven by a direct AC power source, and continuous driving is possible without a period during which the LED does not light.

Further, since the frequency of the current ripple of the LED constituting the light emitting portion is converted into four times the frequency of the AC power source, it is not easily felt by the flicker in the human eye. Further, even if a current is smoothed by adding a capacitor in parallel to the LED column constituting the light emitting portion, Since the frequency is high, an equal smoothing effect can be obtained with a small capacity, and a reduction in the power factor is also small.

Therefore, a phenomenon that may occur when an LED is driven by an AC power source such as a flicker, a drop in the power factor, or a fluctuation in the LED current due to a power source voltage fluctuation can be solved by a simple circuit.

That is, in the LED driving circuit not using the SMPS, the LED current can be controlled with a small power loss.

1 is a circuit diagram showing an example of a light emitting diode illumination system.
2 is a circuit diagram showing another example of the light emitting diode illumination system.
Fig. 3 is a waveform diagram showing an example of an operation waveform by the circuit of Fig. 2. Fig.
Fig. 4 is a graph showing the result of improvement in dependence of the current on the power supply voltage by the circuit of Fig. 2. Fig.
5 is a circuit diagram showing an example in which a current detection circuit is added to the circuit of Fig.
Figs. 6A and 6B, Figs. 10A and 10B are diagrams showing operations and waveforms of a discharge period by the circuit of Fig.
Figs. 7A and 7B and Figs. 9A and 9B are diagrams showing the operation and waveform of the conduction period by the circuit of Fig.
8A and 8B are diagrams showing the operation and waveform of the charging period by the circuit of Fig.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. Rather, the intention is not to limit the invention to the particular forms disclosed, but rather, the invention includes all modifications, equivalents and substitutions that are consistent with the spirit of the invention as defined by the claims.

It will be appreciated that when an element such as a layer, region or substrate is referred to as being present on another element "on," it may be directly on the other element or there may be an intermediate element in between .

Although the terms first, second, etc. may be used to describe various elements, components, regions, layers and / or regions, such elements, components, regions, layers and / And should not be limited by these terms.

1, the LED lighting system includes a rectifying section 20 for rectifying an AC power source 10, which includes a first terminal 21 and a second terminal 22 do.

The rectifying unit 20 may use a bridge diode. In this bridge diode, the alternating-current power source 10 may be full-wave rectified to have a ripple voltage.

The light emitting unit 30 including a plurality of LEDs L1, ..., Ln connected in series is connected to the first terminal 21 of the rectifying unit 20. [ At this time, the light emitting unit 30 is connected to the first terminal 21 so that the anode of the LED, that is, the anode is connected.

The light emitting unit 30 is connected to the light emitting unit 40. The charging unit 40 is connected between the light emitting unit 30 and the second terminal 22 of the rectifying unit 20 and has a charging path connected to the cathode of the light emitting unit 30, that is, the cathode.

Further, the charging and discharging unit 40 is connected to the anode of the light emitting unit 30, and has a discharging path through which charges are discharged toward the anode side.

The charging unit 40 includes a capacitor C1 connected in series with the light emitting unit 30 and includes a diode for forming a charging path and a discharging path of the capacitor C1.

That is, this diode is connected between the capacitor C1 and the cathode of the light emitting unit 30 and includes a first diode D1 and a capacitor C1 and a light emitting unit 30 connected in a forward direction to the capacitor C1, And a second diode D2 connected between the anode of the first diode D2 and the anode of the second diode D2.

The power controller 50 is connected in parallel with the charging unit 40 to control the flow of the current flowing through the charging unit 40. [

The power control unit 50 may include a power control device F1 connected to the light emitting unit 30 and a control circuit 51 for controlling the power control device F1. As this power control element F1, a metal-oxide-semiconductor field-effect transistor (MOSFET) element can be used, and a bi-polar transistor can also be used.

At this time, the control circuit 51 detects the operating voltage of the light emitting portion 30 and controls the power control element F1 to control the flow direction of the current.

That is, the control circuit 51 controls the voltage of the capacitor C1 of the charging and discharging unit 40 to be higher than the operating voltage of the light-emitting unit 30 when the voltage passing through the rectifying unit 20 is higher than the operating voltage of the light- And controls the current to flow to the light emitting portion 30 when the current is low.

When the voltage passing through the rectifying section 20 is higher than the operating voltage of the light emitting section 30 plus the voltage of the capacitor C1 of the charging and discharging section 40, the control circuit 51 causes the light emitting section 30 So that the capacitor C1 is charged.

The control circuit 51 controls the circuit so as to discharge the charge of the capacitor C1 of the charging part 40 when the voltage passing through the rectifying part 20 is lower than the operating voltage of the light emitting part 30 .

On the other hand, the current smoothing unit C2 is connected to the light emitting unit 30 so that current flowing through the light emitting unit 30 is smoothed to suppress current pulsation.

Hereinafter, the configuration and operation of the circuit as shown in Fig. 1 will be described in detail.

As described above, such an LED lighting circuit is constructed such that the ripple voltage rectified by the bridge diode 20 of the AC power source 10 is supplied to the rectifying unit 20 through the circuit in which the light emitting unit 30 and the capacitor C1 are connected in series, To the second terminal (22).

Further, the second diode D2 is connected from the positive electrode of the capacitor C1 to the anode of the light emitting portion 30 connected in series. The drain (or collector) of the power control element F1 is connected to the cathode of the light emitting portion 30 including the series-connected LEDs L1, ..., Ln, Or emitter) is connected to the second terminal 22 of the rectifying unit 20. [

The gate (or base) of the power control element F1 is set to "high" (SW ON) when the ripple voltage of the bridge diode output forming the rectifying section 20 is lower than the operation voltage Vf of the light- Quot; low "(SW OFF) state when the pulsating voltage is higher than the sum of the operating voltage Vf of the light emitting portion 30 and the voltage of the capacitor C1, When the current value is higher than the operation voltage Vf of the light emitting unit 30 and lower than the operation voltage Vf of the light emitting unit 30 plus the voltage of the capacitor C1, And is controlled by the control circuit 51.

When the pulsating voltage is higher than the sum of the operating voltage Vf of the light emitting portion 30 and the voltage of the capacitor C1, the charging current flows through the light emitting portion 30 and the first diode D1, Charge is accumulated.

When the operating voltage Vf of the light emitting unit 30 is set to a value lower than half of the peak voltage of the pulsating power supply voltage, the capacitor C1 is charged to a voltage higher than the operating voltage Vf of the light emitting unit 30. [ do.

When the power control element F1 is turned on during a period when the pulsating current source voltage is lower than the operating voltage Vf of the light emitting portion 30, a reverse voltage is applied to the rectifying portion 20, The electric charge stored in the capacitor C1 is discharged through the second diode D2, the light emitting portion 30, and the power control element F1.

When the pulsating voltage is higher than the operating voltage Vf of the light emitting portion 30 and lower than the sum of the operating voltage Vf of the light emitting portion 30 and the voltage of the capacitor C1, Current is appropriately set through the AC power source 10, the rectifying section 20, the light emitting section 30, and the power control element F1.

The operation of the circuit described above makes it possible to flow a current to the light emitting portion 30 during each of the charging period and the discharging period when the capacitor C1 is charged and the capacitor C1 is discharged.

Here, the amount of electric charge to be charged in the capacitor C1 and the amount of electric charge to be discharged are automatically balanced.

Therefore, a method of shortening the on-time of the power control element F1 during the discharge period of the capacitor C1 or limiting the discharge current by operating the power control element F1 in the active region By reducing the amount of charge discharged through the capacitor, the amount of charge to be charged can be reduced as well.

As a result, it is possible to control the power to be inputted from the AC power source 10 and the average current of the light emitting portion 30 to be decreased.

Since the charging current and the discharging current of the capacitor C1 flow once every 1/2 cycle of the AC power supply to the light emitting portion 30, the ripple frequency of the current flowing to the light emitting portion 30 is the same as that of the AC power supply 10 It is converted to four times the frequency and is not easily recognized as a flicker in the human eye.

On the other hand, by connecting the current smoothing unit C2 to the light emitting unit 30 in parallel, the current flowing through the light emitting unit 30 is smoothed and the ripple of the current can be suppressed. This current smoothing unit C2 can use the electrolytic capacitor C2.

However, in the case where the capacitor C2 is not provided, a current flowing until the capacitor C1 of the charging and discharging unit is charged to a predetermined voltage flows through the light emitting unit 30 at the time of power supply connection, This current flows mainly to the capacitor C2 by adding the capacitor C2 for the light emitting portion 30, so that the current flowing through the light emitting portion 30 can be suppressed.

Fig. 2 shows another example of the configuration of the control circuit 51. Fig. An example in which the charging current detecting resistor R1 and the discharging current detecting resistor R2 are further provided between the source of the power control element F1 and the control circuit 51 in connecting the control circuit 51 is shown .

The current detection signal input section 52 is further included by bypassing the two resistors R1 and R2 and directly connecting the source of the power control element F1 and the control circuit 51. [

Here, it further includes a voltage input part 53 connected directly to the capacitor C2 terminal for current smoothing to detect the operating voltage of the light emitting part 30. [

Therefore, the detection signal of the current detection signal through the current detection signal input unit 52, the output voltage of the rectification unit 20, and the operation voltage Vf of the light emitting unit 30 through the voltage input unit 53 is supplied to the control circuit 51 ).

At this time, the capacitor C1 of the charging and discharging unit 40 is connected between the charging current detecting resistor R1 and the discharging current detecting resistor R2.

In this circuit configuration, the discharging current of the capacitor C1 of the charging portion 40 is connected to the second diode D2, the light emitting portion 30, the power control element F1, and the discharging current detecting resistor R2 The current flows to the negative terminal of the capacitor C1 and does not flow to the charge current detection resistor R1.

Therefore, the charge current detection resistor R1 does not affect the current detection signal through the current detection signal input part 52 at the time of discharging the capacitor C1.

Likewise, at the time of charging the capacitor C1, the alternating-current power supply 10, the rectifying unit 20, the light emitting unit 30, the first diode D1, the capacitor C1, and the charging current detecting resistor R1 The current detection signal input through the current detection signal input part 52 is determined by the charge current detection resistor R1 and the charge current and is supplied to the discharge current detection resistor R2).

Through the capacitor C1 via the rectifying section 20, the light emitting section 30, the power control element F1, the discharging current detecting resistor R2 and the charging current detecting resistor R1 from the AC power supply 10, Both the discharge current detection resistor R2 and the charge current detection resistor R1 can influence the current detection signal.

Since the flow of the three currents is temporally separated, it is possible to calculate the LED drive current in the control circuit 51 from the value of the current detection signal through the current detection signal input section 52. [

Fig. 3 shows an example of the operation waveform by the circuit of Fig.

Each of the waveforms has a ripple voltage 74 rectified by the rectifying section 20, an output current 72 of the rectifying section 20, a current 73 of the light emitting section 30, (Collector) current 74, respectively.

A period in which the pulsating voltage rectified in the rectifying section 20 is lower than the operating voltage Vf of the light emitting section 30 becomes a "discharge period" for discharging the electric charge of the capacitor C1. That is, among the drain (collector) current 74 of the power control element F1, the discharge current flows in the discharge period. The peak value of the discharge current is controlled by the control circuit 51 such that the voltage across both ends of the discharge current detecting resistor R2 does not exceed a predetermined set value.

When the output voltage of the rectifying section 20 is higher than the operating voltage Vf of the light emitting section 30 and lower than the sum of the operating voltage Vf of the light emitting section 30 and the voltage of the capacitor C1, So that current flows to the light emitting portion 30 without passing through the capacitor C1.

The current waveform is controlled by the control circuit 51 to be a predetermined waveform based on the power supply voltage detection signal through the voltage input section 53 and the current detection signal through the current detection signal input section 52. [

3, among the output currents 72 of the rectifying unit 20, the current flowing in the conduction period is a current supplied from the alternating-current power supply 10 in the "conduction period ".

Charging period "when the pulsating voltage rectified by the rectifying unit 20 is higher than the sum of the voltages of the light emitting unit 30 and the capacitor C1 and the rectifying unit 20 and the light emitting unit 30 ), And the first diode D1 to the capacitor C1.

3, among the output current 72 of the rectifying section 20, the current flowing in the charging period is the charging current.

Thus, the electric current flowing in the "discharge period", the "conduction period" and the "charge period" flows to the light emitting section 30 and the smoothing capacitor C2 connected in parallel to the light emitting section 30. The current 73 of the light emitting portion 30 is smoothed by the smoothing capacitor C2 so that the ripple can be reduced.

Here, in the current waveform, it can be seen that the peak current is limited in the discharge current waveform 74, and a portion having a large current is almost a square wave.

Therefore, when the discharge current is controlled so as to be constant over the period in which the peak current is reached, the discharge charge is balanced with the charge charge, so that the charge current becomes almost constant. As a result, the current flowing through the light- .

Fig. 4 shows the result that the power supply voltage dependency of the current flowing through the light emitting portion 30 is improved by the circuit of Fig. As a graph of LED power deviation and AC power deviation, it can be seen that the graph is nearly linear.

That is, it can be seen that the increase / decrease of the AC power deviation is almost constant with respect to the variation of the LED power supply deviation.

The LED lighting system described above can be driven by an AC power source directly in an LED driving circuit using an AC power source that does not use an SMPS (Switching Mode Power Supply), and can be driven continuously This is possible.

Further, as described above, since the frequency of the current ripple of the LED constituting the light emitting portion 30 is converted to four times the frequency of the AC power source, it is not easily felt by the flicker in the human eye, Even when the capacitor is added in parallel to smooth the current, since the ripple frequency is high, an equal smoothing effect can be obtained with a small capacity, and a reduction in the power factor is also small.

Therefore, a phenomenon that may occur when an LED is driven by an AC power source such as a flicker, a drop in the power factor, or a fluctuation in the LED current due to a power source voltage fluctuation can be solved by a simple circuit.

That is, in an LED driving circuit that does not use the SMPS, the LED current can be controlled with a small power loss.

5, a current detection circuit 60 for directly detecting the current of the light emitting portion 30 is added to the circuit of Fig. 3, and the current detection signal of the light emitting portion 30 by the current detection circuit 60 is controlled Circuit 51 as shown in Fig.

Hereinafter, the operation of the circuit of FIG. 1 will be described in detail as time progresses.

First, the operation in a period in which the pulsating voltage Vr is lower than the operation voltage Vf of the light emitting portion 30 will be described with reference to the pulsating voltage passing through the rectifying portion 20. FIG.

That is, in consideration of the operating voltage Vf of the second diode D2 in the configuration of the circuit of Fig. 1, the voltage Vc of the capacitor C1 minus the operating voltage Vf of the second diode D2 The power control element F1 is turned on and the current Isw flows through the power control element F1 as shown in Figs. 6A and 6B.

As described above, the power control element F1 is turned on during the period when the pulsating voltage Vr is lower than the operating voltage of the light emitting portion 30, and a reverse voltage is applied to the rectifying portion 20, , The electric charge accumulated in the capacitor C1 is discharged through the second diode D2, the light emitting portion 30 and the power control element F1.

Here, the pulsating voltage Vr, the voltage Vd applied to the power control element F1, and the input current Iin may substantially coincide in phase.

Since the charging voltage and the discharging voltage of the capacitor C1 are controlled at a level having a constant width and the capacitor C1 having a larger capacity than the charging voltage and the discharging voltage can be provided, It can be much larger than the smoothing capacitor in the drive.

A description will be given of a section in which the pulsating voltage Vr is higher than the operation voltage of the light emitting section 30 and lower than the sum of the operation voltage Vled of the light emitting section 30 and the voltage of the capacitor C1.

In other words, if the operating voltage Vf of the first diode D1 and the operating voltage Vf of the second diode D2 are considered together in the configuration of the circuit of Fig. 1, the second diode D2 Is smaller than the sum of the voltage (Vc) of the capacitor (C1), the operating voltage (Vf) of the first diode (D1) and the operating voltage (Vled) of the light emitting portion (30) 7A and 7B, the power control element F1 is controlled in the active region.

Therefore, a current appropriately set flows through the AC power source 10, the rectifying section 20, the light emitting section 30, and the power control element F1.

Next, a description will be given of a section in which the pulsating voltage Vr is higher than the sum of the operating voltage Vled of the light emitting section 30 and the voltage Vc of the capacitor C1.

1, the pulsating current voltage Vr is lower than the operating voltage Vled of the light emitting portion 30, the voltage Vc of the capacitor C1, and the operating voltage Vf of the first diode D1 The capacitor C1 is charged from the AC power source 10 through the rectifying section 20, the light emitting section 30 and the first diode D1 as shown in Figs. 8A and 8B.

Next, the voltage (Vc) of the capacitor (C1), the operating voltage (Vf) of the first diode (D1) and the voltage (Vf) of the second diode (D2) The power control element F1 is controlled in the active region, as shown in Figs. 9A and 9B.

Therefore, a current appropriately set flows through the AC power source 10, the rectifying section 20, the light emitting section 30, and the power control element F1. The operation in this state operates in the same manner as the state shown in Figs. 7A and 7B.

Thereafter, when the state of the circuit of Fig. 1 is again lower than the voltage Vc of the capacitor C1 minus the operating voltage Vf of the second diode D2, as shown in Figs. 10A and 10B Likewise, the power control element F1 is turned on and the current Isw flows through the power control element F1.

As described above, the power control element F1 is turned on during a period when the pulsating current source voltage is lower than the operating voltage of the light emitting portion 30, and a reverse voltage is applied to the rectifying portion 20, The charge accumulated in the capacitor C1 is discharged through the second diode D2, the light emitting portion 30 and the power control element F1, which is the same as the state shown in Figs. 6A and 6B.

It should be noted that the embodiments of the present invention disclosed in the present specification and drawings are only illustrative of specific examples for the purpose of understanding and are not intended to limit the scope of the present invention. It will be apparent to those skilled in the art that other modifications based on the technical idea of the present invention are possible in addition to the embodiments disclosed herein.

10: AC power supply 20:
30: light emitting portion 40:
50: power control unit 60: current detection circuit

Claims (20)

A rectifying section for rectifying AC power and including a first terminal and a second terminal;
A light emitting unit including a plurality of LEDs connected to the anode of the rectifying unit;
A charging unit connected in series with the light emitting unit and connected between the light emitting unit and the second terminal of the rectifying unit and having a charging path connected to the cathode of the light emitting unit and a discharging path connected to the anode of the light emitting unit; And
A current detection signal input unit connected to a source of the power control device for controlling the power control device and a current detection signal input unit for controlling an operation voltage of the light emitting unit, A charging current detection resistor and a discharging current detection resistor connected between a source of the power control device and the control circuit, wherein the charging current detection resistor and the discharging current detection resistor And a power control unit connected to the charge / discharge unit. The control circuit according to claim 1, wherein the control circuit controls the current to flow to the light emitting unit when a voltage passing through the rectifying unit is higher than an operation voltage of the light emitting unit and lower than a sum of the operation voltage and the charge- Characterized by a light emitting diode lighting system. The control circuit according to claim 1, wherein when the voltage passing through the rectifying unit is higher than a sum of an operating voltage of the light-emitting unit and a voltage of the charge-discharge unit, the control circuit charges the charge- And a light emitting diode (LED) 2. The light emitting diode illumination system according to claim 1, wherein the control circuit discharges the charge of the charging unit when the voltage passing through the rectifying unit is lower than the operating voltage of the light emitting unit. delete delete delete The charge / discharge unit according to claim 1,
A capacitor; And
And a diode for discharging and charging the capacitor. 9. The device of claim 8,
A first diode connected between the capacitor and the cathode of the light emitting portion and connected in the forward direction in the capacitor direction; And
And a second diode connected between the capacitor and the anode of the light emitting portion and connected in the forward direction in the anode direction. The light emitting diode lighting system according to claim 1, further comprising a capacitor for smoothing a current input to the light emitting unit. The light emitting diode illumination system according to claim 1, further comprising a current detection circuit for detecting a current flowing in the light emitting portion. The light emitting diode lighting system according to claim 1, wherein the control circuit controls the power control element to be on / off or actively controlled according to a magnitude of an output voltage of the rectifying part. In a light emitting diode illumination system,
A light emitting unit including a plurality of light emitting diodes connected in series;
A rectifying unit for rectifying the AC power and supplying the pulsating voltage outputted to the light emitting unit;
A charging unit connected to the light emitting unit; And
A power control element connected to the light emitting unit, and a control circuit for controlling the power control element, wherein the power control element is connected in parallel to the charging unit, and when the magnitude of the pulsating current voltage satisfies the first condition, When the magnitude of the pulsating current voltage satisfies the second condition, the power control element is turned off so that a current flows to the light emitting portion, and at the same time, And the power control element is turned on when the magnitude of the pulsating voltage satisfies the third condition, and the light emitting portion, the charge discharge portion, and the power control element form a closed circuit to charge the charge portion And a power controller for driving the light emitting unit by discharging the light emitting diode. 14. The light emitting diode lighting system according to claim 13, wherein the first condition is a case where the pulsating voltage is higher than an operation voltage of the light emitting unit and lower than a value obtained by adding the voltage of the charge discharge unit to the operation voltage. 14. The light emitting diode illumination system according to claim 13, wherein the second condition is a case where the pulsating voltage is higher than a sum of an operation voltage of the light emitting portion and a voltage of the charge-discharge portion. 14. The light emitting diode illumination system according to claim 13, wherein the third condition is that the ripple voltage is lower than the operation voltage of the light emitting portion. 14. The light emitting diode lighting system according to claim 13, wherein the charge / discharge unit has a charge path connected between the light emitting unit and the rectifying unit and connected to the cathode of the light emitting unit, and a discharge path connected to the anode of the light emitting unit. . delete 14. The light emitting diode illumination system according to claim 13, wherein the power control unit further comprises a charge current detection resistor and a discharge current detection resistor connected between the source of the power control element and the control circuit. 14. The control circuit according to claim 13,
A current detection signal input unit connected to a source of the power control device; And
And a voltage input unit for detecting an operating voltage of the light emitting unit.

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