WO2015099340A1

WO2015099340A1 - Apparatus and method for controlling energy recycling led having high power factor

Info

Publication number: WO2015099340A1
Application number: PCT/KR2014/012281
Authority: WO
Inventors: 고관수
Original assignee: 고관수
Priority date: 2013-12-28
Filing date: 2014-12-12
Publication date: 2015-07-02
Also published as: KR20150077608A; KR101574942B1

Abstract

The present invention relates to an apparatus for controlling an energy recycling LED having a high power factor, the apparatus comprising: a power supply unit; an LED lamp lit by power supplied by the power supply unit; a charging capacitor connected to the LED; a charging current control unit connected to the charging capacitor; and a main current control unit connected in series to the LED and connected in parallel to the charging capacitor and the charging current control unit, wherein the charging current control unit controls at least a part of the supplied power to be charged in the charging capacitor. According to the present invention, the present invention has an advantage of recycling energy lost of the end of an LED.

Description

Energy recycling high power factor LED control device and method

The present invention relates to a light emitting diode (LED) control apparatus and method, and more particularly, to an energy recycling high power factor LED control apparatus and method capable of controlling a high power factor LED by reusing energy supplied to the LED.

In general, an LED driver or an LED power supply is required to drive an LED (eg, an LED lamp). Traditional AC-DC power supplies and DC-DC converters provide constant-voltage at the output. However, LEDs operate most efficiently and reliably when driven at constant-current. Accordingly, in order to drive the LED, constant current control is performed by applying a switching mode power supply (SMPS) method, which is a high frequency switching technology.

As the LED is a current driving method, the constant current driving method using the SMPS is evaluated as a very suitable driving method, but it has various disadvantages. For example, the constant current driving method using the SMPS is difficult to incorporate in a device due to its large size due to a complicated circuit structure, a passive element such as an inductor, an 'Al-Cap', and the like.

In addition, in the driving method using the SMPS, harmful electromagnetic waves are generated due to high frequency switching, and the price structure of the LED driver is continuously required due to the expensive LED lamp price structure.

1 is a conventional AC direct drive 2-wire LED control circuit diagram. Referring to FIG. 1, the conventional AC direct drive two-wire LED control method is a concise control method that has approached to innovatively improve the unit cost of LED drivers as much as about 25% to promote LED sales. Therefore, the price is quite attractive, but the efficiency is too low has the disadvantage of less energy saving effect.

In addition, there is a problem of lowering the brightness (luminous flux) of the LED lamp against the input voltage fluctuation and a problem of rapidly decreasing efficiency at a high input voltage range, and failing to satisfy the power factor (PF) and THDi and having a very weak reliability. .

On the other hand, a multi-tap control method has been proposed as another conventional AC direct drive method having improved efficiency and power factor (PF). The multi-tap control method is a proposed method for improving the power factor (PF) and driving efficiency which are problematic in the AC direct drive two-wire control method as shown in FIG. 1, and maximizes the control tap for LED light emission. PF) and driving efficiency can be maximized. However, there is a problem in the heat dissipation design reliability of the group 1 LED which flows the most current due to the large number of multi-tap control circuit connection lines, which can be complicated, and the driving currents between the respective control groups are different.

In addition, due to the difference in driving current between the groups, the brightness of the LED may be different for each group, especially when applied to a straight-type LED lamp may have a lot of design difficulties and light quality may be degraded. Accordingly, it is desirable to minimize complicated circuit lines for a reasonable heat dissipation design in which a high heat LED light source (SMD component) is mounted. Therefore, most AC direct drive controllers (ICs) are manufactured and sold at the 3 ~ 6 stage S / W control level. It is difficult to maximize efficiency, which is its original purpose, and its structure is limited to small capacity (about 15W or less) because it is difficult to drive medium and large capacity due to its on-board mounting type.

Also, as shown in FIG. 2, all energy clamped to the LED (e.g., a voltage higher than the LED V _F voltage) acts as a driving loss, so that the input voltage variation (used recommended voltage) is set to ± 5% It should be stable to satisfy ± 10%. That is, there is still a problem in the variation of the input power and luminous flux output against the input voltage variation. In addition, a large number of control taps increases the electromagnetic interference (EMI) value, requiring a separate EMI filter. Therefore, it is difficult to rational design, and optical flickering of the lighting equipment is the biggest problem currently pointed out because of the AC direct drive structure. Structural improvement is difficult.

The present invention was created to solve the problems of the prior art as described above, the energy recycling high power factor LED control apparatus and method according to the present invention to eliminate the middle tap (Tap) of the LED load and control the LED load with two pins. Power factor and efficiency can be improved by recycling the lost energy of the LED termination and energy below the LED threshold voltage.

In addition, the energy recycling high power factor LED control apparatus and method according to the present invention can provide a high reliability, eco-friendly LED lamp having a concise drive structure to minimize EMI and flickering.

Energy recycling high power factor LED control device according to the present invention for achieving the above object, the power supply for rectifying and supplying AC input power; At least one light emitting diode (LED) lit by power supplied from the power supply unit; A charging capacitor connected in series with the LED; A charging current controller connected in series with the charging capacitor; And a main current controller connected in series with the LED and connected in parallel with the charging capacitor and the charging current controller, wherein the charging current controller includes a voltage exceeding an LED driving threshold voltage. And control at least part of the supplied power to charge the charging capacitor.

Preferably, the power supply unit includes a bridge diode for full-wave rectifying the AC input power.

Preferably, the charging current control unit includes at least one switching element.

Preferably, the switching element is any one or more selected from transistors, FETs, MOSFETs, OP-AMPs, and switches.

Preferably, the main current control unit includes at least one switching element.

Preferably, the device is connected in parallel with the LED, the secondary charge current controller for providing a secondary charging voltage to the charging capacitor when the voltage applied to the LED falls below the LED driving threshold voltage; It includes more.

Preferably, the secondary charging current control unit includes at least one switching element.

Preferably, the apparatus further comprises a second capacitor connected in parallel with the LED to prevent flickering of the LED.

Preferably, the apparatus further comprises a first resistor connected in series between the power supply and the LED to distribute the AC input power input from the power supply.

Advantageously, the apparatus comprises: a second resistor connected in parallel with said first resistor to distribute AC input power input from a power supply; A third resistor connected in series with the second resistor; A first OP-AMP comparing a voltage applied to the lower end of the second resistor with a reference voltage to provide a control signal to the charging current controller; And a second OP-AMP comparing the voltage applied to the lower end of the second resistor with a reference voltage to provide a control signal to the main current controller.

Preferably, the apparatus further comprises a third capacitor connected in parallel with the third resistor to remove the ripple of the voltage applied to the third resistor.

Preferably, the apparatus further includes a discharge voltage control unit connected in parallel with the LED and the charging capacitor, wherein the discharge voltage control unit, the charging capacitor is secondary charge by the secondary charging current control unit When the voltage applied to the LED rises again and exceeds the preset voltage value V ₃ , the power charged in the charging capacitor and the power supplied from the power supply unit are combined to control the LED to be turned on.

Preferably, the predetermined voltage value V ₃ is a difference between the LED driving threshold voltage and the voltage charged secondary to the charging capacitor.

Energy recycling high power factor LED control method according to another embodiment of the present invention for achieving the above object, in the energy recycling high power factor LED control method for driving at least one LED by an AC input power, Rectifying an input power and providing the LED to the LED; Determining whether a voltage applied to the LED exceeds a LED driving threshold voltage in a first cycle period of the rectified AC input power; And when the voltage applied to the LED exceeds the LED driving threshold voltage, operates the first operation mode in which at least a part of the power supplied to the LED is first charged to a charging capacitor connected in series with the LED. It comprises; a.

Preferably, the method of rectifying the AC input power includes full-wave rectifying the AC input power by a bridge diode.

Preferably, after the first mode of operation, when the voltage of the voltage applied to the LED in the first cycle period of the rectified AC input power passes 90 ° and the voltage drops, the primary of the charging capacitor And operating in a second mode of operation for terminating charging.

Preferably, after the second mode of operation, when the voltage applied to the LED falls below the LED driving threshold voltage, the second capacitor for charging the charging capacitor secondary to at least a portion of the power supplied to the LED And operating in three operation modes.

Preferably, after the third operation mode, when the voltage applied to the LED rises again in the second cycle section of the rectified AC input power and exceeds the preset voltage value V ₃ , the charging capacitor And combining the charged power with the rectified AC input power and operating in a fourth operation mode of turning on the LED.

Preferably, the preset voltage value V ₃ is a difference between the LED driving threshold voltage and the voltage charged secondary to the charging capacitor.

As described above, according to the present invention, the two-wire control of the LED load is possible in the AC direct drive method, so that the separate design is very easy and the range of driver application can be applied without limitation to medium and large capacity.

In addition, according to the present invention, by reusing the clamping voltage of the LED terminal, it is possible to solve the power factor drop problem (can be arbitrarily set to 0.9 or more), improve the efficiency (about 85%), and stabilize the input power deviation.

In addition, according to the present invention, it is possible to minimize the flicker percentage according to the EMI (radio frequency) free and option selection.

In addition, according to the control method of the present invention, it is possible to zero the current and luminous flux deviation problems between the LEDs, and the LEDs may be optimized to bring about cost improvement. In addition, the design reliability of the LED lamp can also be stabilized.

1 is a conventional AC direct drive 2-wire LED control circuit diagram.

2 is a graph comparing loss waveforms in a conventional AC direct drive two-wire LED control circuit.

3 is a circuit diagram of an energy recycling high power factor LED according to an embodiment of the present invention.

4 is an operation timing diagram of an energy recycling high power factor LED control circuit according to an embodiment of the present invention.

5 to 8 are diagrams showing current flow in respective operation modes of the energy recycling high power factor LED control circuit according to an embodiment of the present invention.

9 is a circuit diagram illustrating an energy recycling high power factor LED according to another embodiment of the present invention.

10 is a flowchart illustrating an energy recycling high power factor LED control procedure according to an embodiment of the present invention.

Embodiments of the present invention may be variously modified and have various embodiments, and specific embodiments will be described in detail with reference to the accompanying drawings. However, this is not intended to limit the embodiments of the present invention to specific embodiments, it should be understood to include all changes, equivalents, and substitutes included in the spirit and scope of the embodiments of the present invention.

Terms including ordinal numbers such as first and second may be used to describe various components, but the components are not limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the embodiments 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. The term and / or includes a combination of a plurality of related items or any item of a plurality of related items.

The terms used in the embodiments of the present invention are merely used to describe specific embodiments, and are not intended to limit the embodiments of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In embodiments of the present invention, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or the same. It is to be understood that the present invention does not exclude in advance the possibility of the presence or addition of other features, numbers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which embodiments of the present invention belong. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art, and ideally or excessively formal meanings, unless explicitly defined in the embodiments of the present invention. Not interpreted as

The present invention proposes an I _F current, an input power, and a power factor control circuit of a light emitting LED for lighting in an AC direct driving method which is one of LED lighting driving methods.

The energy recycling high power factor LED control apparatus and method according to the present invention controls the input power factor (PF) and power by recycling the loss energy of the termination higher than the LED driving threshold voltage (V _F ) and the unutilized energy lower than the LED V _F. can do. In addition, the energy recycling high power factor LED control apparatus and method according to the present invention, by inserting any (mandatory) charging energy anywhere in the series line between the AC line LED, and inserting the AC input divider voltage on top of the current feedback resistor input voltage The input power for fluctuations can be actively controlled.

To this end, in the embodiment of the present invention by placing a capacitor on the LED driving circuit to accumulate the loss energy of the LED termination in the capacitor to be recycled. In addition, since the LED does not operate below the LED driving threshold voltage, energy that is lost below the threshold voltage is accumulated in the capacitor so that it can be recycled. In this way, energy reuse is possible and harmful flicker hardly occurs, and no radiated electromagnetic waves are generated.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement the present invention.

3 is a circuit diagram of an energy recycling high power factor LED control device according to an embodiment of the present invention. Referring to FIG. 3, an apparatus according to an exemplary embodiment of the present invention may include a power supply including an input power source 101 and a bridge diode 102, an LED 106 lit by power supplied from the power supply unit, and the LEDs. Main current control unit 116 for controlling the constant current current flowing through the 106, the charging current control unit for charging the second capacitor (C2) 113 by controlling the charging current by the primary charging and secondary charging described later ( 114), a secondary charging current controller 110 for controlling secondary charging of the second capacitor 113, and a main current detector for sensing each main current input to the circuit and controlling each MOSFET to change each operation mode. 130 may be configured to include.

More specifically, first, a commercial AC 220V power source may be supplied to the input power source (Vin) 101, and the application of the present invention is not limited to the voltage level.

The input power source 101 is full-wave rectified through the bridge diode 102, and then at least one LED 106 (or HV) via the first resistor (R1) 103 and the first diode (D1) 104. LED). The LED 106 may be turned on when the voltage V _IN of the supplied electric power is greater than or equal to a predetermined LED driving threshold voltage LED V _F. On the other hand, the magnitude of the voltage of the rectified power from the input power source 101 is changed according to the phase as shown by BD + in FIG. Therefore, in the present invention, the energy is charged to the second capacitor 113 in a section in which the voltage of the power supplied to the LED 106 exceeds the LED driving threshold voltage (LED V _F ), and this is the LED driving voltage (LED). By discharging in the section below V _F ), the power factor may be increased while reusing energy.

Hereinafter, a specific operation of the circuit shown in FIG. 3 will be described in more detail with reference to FIGS. 4 and 5.

4 is an operation timing diagram of the energy recycling high power factor LED control circuit according to an embodiment of the present invention, Figures 5 to 8 are each operation mode of the energy recycling high power factor LED control circuit according to an embodiment of the present invention Is a diagram showing the voltage and current flow in.

The input power source 101 is full-wave rectified through the bridge diode 102, and the full-wave rectified input voltage V _IN gradually rises. Until the input voltage reaches the LED driving threshold voltage V _F , no current flows in the LED 106, so that the LED is not turned on. Accordingly, the first MOSFET 115, the second MOSFET 117, the third MOSFET 108, and the fourth MOSFET 111 may be in an off state in which no current flows.

When the input voltage V _IN continues to rise to reach the LED driving threshold voltage V _F , a first diode D1 104, an LED 106, a third diode D3 112, and a second Current flows through the capacitor (C2) 113 and the first MOSFET (Q1) 115 so that the primary charging current (Irtc) flows through the second capacitor (C2) 113. Accordingly, the LED 106 is turned on and primary voltage charging (V _1C2 = V _IN -V _LED ) proceeds to the second capacitor 113. In the present invention, this is referred to as a first operation mode for convenience, and the current flow in the first operation mode may be schematically illustrated as shown in FIG. 5.

In this case, the main current detector 130 may detect the main currents R1 and MCS- to turn off the third MOSFET Q3 108 so that the LED lighting and charging procedure in the first operation mode may proceed normally. . Accordingly, as shown in FIG. 4, Irtdc becomes zero. In addition, the main current detector 130 detects whether the input voltage V _IN rises to reach the LED driving threshold voltage V _F , and triggers the first MOSFET 115 and the second MOSFET 117. By triggering and turning on, the first operation mode may be controlled.

On the other hand, in the second capacitor (C2) 113 as the input voltage (V _IN ) as the maximum voltage, the charging current (Irtc) flowing through the second capacitor (C2) 113 gradually decreases due to the characteristics of the capacitor. As a result, the main current Im flowing to the first diode D1 104, the LED 106, and the second MOSFET Q2 117 increases gradually with the decrease of the charging current. When the charging continues in the first operation mode and the second capacitor C2 113 is first charged, the charging current Irtc does not flow and only the main current Im flows. At this time, the circuit is switched from the first operation mode (primary charging progress and lighting) to the second operation mode (primary charging completion and lighting). As described above, the switching of the operation mode may occur when the phase of the input voltage is 90 °, but the present invention is not limited thereto. In the second operation mode, as shown in FIG. 6, the main current Im flows through the first diode D1 104, the LED 106, and the second MOSFET Q2 117. 106) lights up. However, since the primary charging is completed in the second capacitor 113, the charging current Irtc does not flow. At this time, the first MOSFET (Q1) 115 and the second MOSFET (Q2) 117 are maintained in an on state, and the third MOSFET (Q3) 108 and the fourth MOSFET (Q4) 111 are Can remain off.

On the other hand, after the phase of the voltage applied to the LED 106 in the second operating mode is 90 °, the voltage gradually decreases, and when the voltage reaches the LED driving threshold voltage LED V _F again, the main current Im ) Gradually decreases and switches to the third mode of operation.

In the third operation mode, secondary charging may be performed to the second capacitor C2 113 according to an embodiment of the present invention. In more detail, in the third operation mode, the secondary charge current Iftc may be provided to the second capacitor C2 113 by turning on the fourth MOSFET Q4 111. The second capacitor C2 113 may be secondly charged by receiving the secondary charging current Iftc flowing through the fourth MOSFET Q4 111. Accordingly, the second capacitor (C2) (113) may be charged voltage rises from the first precharge voltage (V _1C2) with the second charging voltage (V _2C2).

Meanwhile, a method of triggering the fourth MOSFET (Q4) 111 to be turned on may be variously implemented according to an embodiment of the present invention. For example, when the main current sensor 130 senses an input voltage and the input voltage V _IN is polled to fall below the LED driving threshold voltage LED V _F , the fourth MOSFET Q4 111 is turned off. Can be triggered on In addition, according to another exemplary embodiment, a timer may be operated without detecting the main current detector 130 to trigger the fourth MOSFET Q4 111 in an on state when a predetermined time elapses. have.

Therefore, as shown in FIG. 7, when the fourth MOSFET (Q4) 111 is turned on and the secondary charging current Iftc flows through the fourth MOSFET (Q4) 111, the secondary charging is performed. The current Iftc is supplied to the second capacitor C2 113 to perform secondary charging. The secondary charging may proceed until the charging voltage V _2C2 of the second capacitor C2 113 that is increasing and the input voltage V _IN falling to the same voltage V ₁ become the same. . Accordingly, the first MOSFET (Q1) 115 in the delay operation may be turned off when the charging voltage is equal to the input voltage. Alternatively, the fourth MOSFET (Q4) 111 may be turned off after a predetermined time after the fourth MOSFET (Q4) 111 is turned on.

In this way, when the fourth MOSFET (Q4) 111 or the first MOSFET (Q1) 115 is turned off, power supply to the second capacitor (C2) 113 is stopped, and secondary charging is terminated. . Accordingly, the third operation mode may end.

On the other hand, when the third operation mode is terminated, the main current detector 130 detects this (eg, after a preset delay operation time) and cuts off the first MOSFET Q1 115. The AC voltage detector 109 then triggers the third MOSFET Q3 108 to be in an on state while the first MOSFET Q1 115 is off. The time point for triggering the third MOSFET (Q3) 108 in an on state may be a time point at which the input voltage V _IN becomes 0V, or may be a time point immediately before 0V (eg, 50V point).

If the time point at which the third MOSFET Q3 108 is turned on is earlier than the time point at which the first MOSFET Q1 115 is turned off, the circuit passing through the MOSFETs is in a short state. This may cause problems.

Therefore, it is preferable to turn off the first MOSFET (Q1) 115 before triggering the third MOSFET (Q3) 108 to an on state. In the present invention, the third MOSFET (Q3) 108 and Irtdc are referred to as a discharge voltage controller.

After the input voltage continues to fall as described above and becomes 0V, the second cycle starts again, and when the input voltage rises, the input voltage V _IN becomes an LED driving threshold according to an embodiment of the present invention. voltage (V _F) before it reaches the said second capacitor (C2) by discharging the voltage charged in the 113, the LED even if the input voltage (V _iN) is before reaching the LED driving threshold voltage (V _F) It can be turned on.

On the other hand, the point at which the LED is turned on is the sum of the input voltage (V _IN ) and the charging voltage charged in the second capacitor (C2) 113, the second cycle is started again, the LED driving threshold voltage ( V _F ) may be the time V ₃ .

Therefore, the following relationship can be established.

Input voltage at discharge point (V ₃ ) = LED driving threshold voltage (V _F ) _-secondary charge voltage (V _2C2 )

Such an operation state is referred to as a fourth operation mode in the present invention.

Therefore, in the fourth operation mode, as shown in FIG. 8, the AC rising voltage passing through the third MOSFET (Q3) 108 and the charging voltage of the second capacitor C2 113 are summed together to determine the sum of the combined voltages. The current is supplied to the LED 106 via the second diode D2 105, so that the LED 106 can be turned on even before the input voltage V _IN reaches the LED driving threshold voltage V _F. .

On the other hand, since the current flowing through the second diode (D2) 105 is a current combined with the charging current, the input current does not flow through the first resistor (R1) 103 and the first diode (D1).

In addition, as shown in FIG. 3, according to an embodiment of the present invention, the input voltage is distributed to the second resistor R2 118 and the third resistor R3 121 to control power of the input voltage. Can be. As a result, the input power variation with respect to the AC input voltage variation can be improved. At this time, the third capacitor (C3) 122 connected in parallel with the third resistor (R3) 121 performs a function of removing the ripple of the voltage applied to the third resistor (R3) 121. can do.

The input voltages divided by the second resistor R2 118 and the third resistor R3 121 are respectively a first OP-AMP (U1A) 119 and a second OP-AMP (U1B) 120. Can be used as the reference voltage of. Accordingly, the main current detector 130 senses an input voltage and inputs the respective OP-

AMPs

119 and 120 to the first MOSFET Q1 120 and the second MOSFET Q2 117 according to the input voltage. ) Can be set to on or off.

Further, according to an embodiment of the present invention, the fifth resistor R5 123 and the fourth resistor R4 (at the lower ends of the first MOSFET Q1 120 and the second MOSFET Q2 117, respectively) 124 may be further provided. The fifth resistor R5 123 and the fourth resistor R4 124 may provide a function as a shunt registor.

In addition, the first capacitor (C1) 107 connected in parallel with the LED 106 in accordance with an embodiment of the present invention flickering (flickering) generated due to the LED 106 is turned on and off in accordance with the cycle of the input voltage It can provide a function to minimize the phenomenon.

The energy recycling high power factor LED control circuit has been described as an example of the apparatus according to the embodiment of the present invention with reference to FIGS. 3 to 5. The circuit of FIG. 3 is an example to help understanding of the present invention, and may be variously modified as shown in FIG. 9 by applying the concept of the present invention. In addition, each of the MOSFETs in FIG. 3 may be replaced with various other types of devices (eg, switching elements). For example, it may be replaced by any device capable of providing the same or similar function (eg, switching function or constant current control function) such as a transistor, a FET, an OP-AMP, a switch, and the like.

9 is a circuit diagram illustrating an energy recycling high power factor LED according to another embodiment of the present invention. Referring to FIG. 9, the circuit of FIG. 3 may be variously modified as shown in accordance with an embodiment of the present invention. Since the operation in the modified embodiment illustrated in FIG. 9 operates similarly to the operations according to each operation mode of FIG. 3, a detailed description thereof will be omitted. Hereinafter, when implemented in the embodiment of FIG. 9, the current flow in each operation mode will be briefly described.

First, in the first mode of operation, the current due to the full-wave rectified input voltage 201 through the bridge diode 202 is applied to the first diode 204, the second capacitor 205, the second diode 206, and the LED 208. ) And the second MOSFET 211. Accordingly, as described above with reference to FIG. 3, when the input voltage 201 rises to reach a driveable threshold voltage of the LED 208, the LED 208 is turned on. In this case, charging of the second capacitor 205 may also proceed simultaneously. In this case, the fourth MOSFET 210 may maintain an off state.

Next, when the second operation mode is entered, the controller 220 turns on the first switch (SW1) 203 so that an input current is directly transmitted to the second diode 206 through the first switch 203. Accordingly, current caused by the input voltage 201 propagated through the bridge diode 202 flows through the first switch 203, the second diode 206, the LED 208, and the second MOSFET 211. . Accordingly, the primary charging of the second capacitor 205 is stopped.

Next, when the third operation mode is entered, the first switch 203 is turned off again, and the fourth MOSFET 210 is turned on, thereby allowing secondary charging of the second capacitor 205 to proceed. Therefore, the current by the input voltage 201 propagated through the bridge diode 202 is transferred through the first diode 204, the second capacitor 205, the fourth MOSFET 210, and the second MOSFET 211. Will flow. Accordingly, the second capacitor 205 may be secondary charged.

Next, in the fourth operation mode, as described above with reference to FIG. 3, the current due to the current input voltage and the discharge current due to the voltage charged in the second capacitor 205 are combined to light the LED 208. have. In this case, the controller 220 may turn on the first switch 203, the second switch 207, and the second MOSFEET 211 and turn off the fourth MOSFET 210. Thus, the current due to the full-wave rectified input voltage 201 through the bridge diode 202 is the first switch 203, the second capacitor 205, the second switch 207, the LED 209 and the second MOSFET Flow through 211. Accordingly, the current charged in the second capacitor 205 is discharged, and the input current and the discharge current are combined and supplied to the LED 208 so that the LED 208 may be turned on.

Meanwhile, in the circuit shown in FIG. 9, at least some elements may be omitted or replaced with other elements. For example, the fourth MOSFET 210 may be omitted or replaced by a switch.

10 is a flowchart illustrating an energy recycling high power factor LED control procedure according to an embodiment of the present invention. Referring to FIG. 10, when V _IN starts to be input (S701) and gradually increases in one cycle, it is determined whether V _IN reaches V _F (LED driving threshold voltage) (S702). When the V _IN reaches V _F , the LED may be turned on by V _IN input as the first operation mode (S703). In addition, according to an embodiment of the present invention, for power exceeding V _F at V _IN , primary charging (S704) may be performed in a charging capacitor connected in series with the LED.

As described above, when V _IN continues to rise and the phase exceeds 90 ° (S705), the second operation mode is switched to stop the primary charging of the capacitor (S706).

Then, when V _IN continues to decrease and falls back below V _F (S707), power supply to the LED is stopped and secondary charging to the capacitor may be started (S708) according to an embodiment of the present invention. have.

When the secondary charging is started and a predetermined time elapses or when the charging voltage V _2C2 reaches the input voltage V ₁ currently being input (S709), the secondary charging may be stopped (S710). .

Then, when one cycle of the input voltage ends, two cycles begin, and the input voltage rises again, the input voltage V _IN is measured, and the input voltage V _IN is measured according to an embodiment of the present invention. The LED can be turned on using the charged power before reaching V _F. For example, when the input voltage V _IN reaches the preset V ₃ (S711), the LED may be turned on (S712) in combination with the charging power of the capacitor even before reaching V _F.

As described above, a preferred embodiment according to the present invention has been described, and the fact that the present invention can be embodied in other specific forms in addition to the above-described embodiments without departing from the spirit or scope thereof is known to those skilled in the art. It is obvious to those who have it.

Therefore, the above-described embodiments should be regarded as illustrative rather than restrictive, and thus, the present invention is not limited to the above description but may be modified within the scope of the appended claims and their equivalents.

Claims

A power supply unit rectifying and supplying AC input power;

At least one light emitting diode (LED) lamp that is turned on by the power supplied from the power supply unit;

A charging capacitor connected in series with the LED;

A charging current controller connected in series with the charging capacitor; And

And a main current controller connected in series with the LED and connected in parallel with the charging capacitor and the charging current controller.

And the charging current controller controls to charge the charging capacitor with at least a part of the supplied power when the voltage applied to the LED exceeds the LED driving threshold voltage.
The method of claim 1, wherein the device,

And a secondary charging current controller connected in parallel with the LED and providing a secondary charging voltage to the charging capacitor when the voltage applied to the LED falls below the LED driving threshold voltage. LED control device.
The method of claim 1, wherein the device,

And a first resistor connected in series between the power supply and the LED to distribute AC input power input from the power supply.
The method of claim 3, wherein the device,

A second resistor connected in parallel with the first resistor to distribute AC input power input from a power supply; A third resistor connected in series with the second resistor; A first OP-AMP comparing a voltage applied to the lower end of the second resistor with a reference voltage to provide a control signal to the charging current controller; And a second OP-AMP comparing the voltage applied to the lower end of the second resistor with a reference voltage to provide a control signal to the main current controller.
The method of claim 1, wherein the device,

And a second capacitor connected in parallel with the LED to control flickering of the LED.
An energy recycling high power factor LED control method for driving at least one LED by an AC input power source,

Rectifying the AC input power to provide the LED to the LED;

Determining whether a voltage applied to the LED exceeds a LED driving threshold voltage in a first cycle period of the rectified AC input power; And

As a result of the determination, when the voltage applied to the LED exceeds the LED driving threshold voltage, operating in a first operation mode of primary charging at least a part of the power supplied to the LED to a charging capacitor connected in series with the LED. Comprising; energy recycling high power factor LED control method.
The method of claim 6, wherein the rectifying of the AC input power source comprises:

And full-wave rectifying the AC input power by a bridge diode.
The method of claim 6, wherein after the first mode of operation,

Operating in a second operation mode in which primary charging of the charging capacitor is terminated when the voltage decreases as the phase of the voltage applied to the LED passes 90 ° in the first cycle period of the rectified AC input power. It further comprises; Energy recycling high power factor LED control method.
The method of claim 8, wherein after the second mode of operation,

When the voltage applied to the LED falls below the LED driving threshold voltage, operating in a third operation mode of charging at least a part of the power supplied to the LED to the charging capacitor secondary; , Energy recycling high power factor LED control method.
The method of claim 9, wherein after the third mode of operation:

When the voltage applied to the LED rises again in the second cycle period of the rectified AC input power and satisfies a preset condition, the power charged in the charging capacitor and the rectified AC input power are combined to turn on the LED. Operating in a fourth mode of operation; further comprising, energy recycling high power factor LED control method.