KR20120096326A - A apparatus of smart dimming converter for led lamp - Google Patents

Abstract

PURPOSE: A smart dimming converter device is provided to control the brightness of an LED lamp by regulating the waveform of current supplied to the LED lamp. CONSTITUTION: A power supply unit(1100) converts commercial AC power into the DC power with a compensated power factor. A pulse width control unit(120) includes a triangular wave generating part and a comparator and switches the input DC power with a pulse width modulation method. A DC-DC converter unit(1300) converts the power switched by the pulse width control unit into the voltage level for driving an LED lamp. An output current smoothing unit(1400) converts the current output from the DC-DC converter unit into the constant current. A dimming control unit(1600) detects the current output from the output current smoothing unit and compensates an error between the detected current and a current setting signal.

Description

Smart dimming converter device {A apparatus of smart dimming converter for LED lamp}

The present invention relates to a smart dimming converter of an LED lamp, and more particularly, to a smart dimming converter device that blocks the flicker phenomenon caused by a low control current in a method of controlling the brightness of the LED lamp with a current.

Humans began to illuminate the surroundings brightly using a flame generated by burning wood, oil, etc., and invented a lighting device using electricity by technology development.

Lighting devices increase the amount of time that humans can be active, making them indispensable not only in everyday life but also in human economic activity.

It is very important that the lighting device is easy to control on and off, and furthermore, it is important to control the brightness.

The lighting device using electricity has been favored by the advantages of easy control and improved more conveniently in use. Recently, a light emitting diode (LED) with low power consumption has been used as a light source.

LEDs have a lifespan of about 100,000 hours, but as the trend continues to increase due to the continuous development of technology, the lifespan is semi-permanent, and high-brightness LEDs that consume watt-class current can be used for industrial purposes as well.

There are largely alternating current (AC) and direct current (DC) in the electricity used by humans, and the electricity that can be used at low cost for home, industrial use, and the like is common in the world.

LED is made of semiconductor (semiconductor) as a material, it is directional, it is common to use direct current (DC) as the operating power source.

When using alternating current (AC) as the operating power of the LED lighting apparatus according to the prior art, it is difficult to manufacture and time-consuming because a plurality of LEDs must be combined in the forward and reverse directions.

The prior art using alternating current has a problem of tired eyes due to the flicker phenomenon in which LEDs appear to blink.

According to the prior art, when driving an LED lighting device (hereinafter, referred to as a “light”) with a direct current, an SMPS (switched mode power supply) or an adapter converting AC into a direct current (adapter) was used.

The adapter or SMPS inputs and rectifies AC of commercial power and converts it to DC, and supplies the converted DC to the operating power of the LED lamp.

Even in the prior art adapter or SMPS device, it may not be possible to completely remove the AC component in the process of rectifying the AC.

In the case of supplying a direct current whose AC component is not completely removed during the rectification process to the LED power source, flicker may occur in the LED, but the flicker may not appear when the amount of current supplied is increased.

On the other hand, in the case of dimming (dimming) device for adjusting the brightness of the LED lamp it is common to use a method for adjusting the amount of current supplied.

In case of using DC as the operating power of LED, pulse width modulation (PWM) and DC-DC conversion method are used to control the amount of current.

The LED can brighten the light by supplying a lot of current, and dim it by reducing the amount of current supplied.

However, if the amount of current supplied to the LED is reduced too much according to the prior art, there is a problem in that the flicker phenomenon occurs on the LED and makes the user's eyes easily tired.

Therefore, there is a need to develop a technology for controlling brightness without flickering on LED lamps.

The present invention for solving the problems and necessity of the prior art is to provide a smart dimming converter device that does not generate a flicker phenomenon at low current while adjusting the brightness of the LED light.

Smart dimming converter device according to an embodiment of the present invention, Smart dimming converter device for adjusting the brightness of the LED light, the power supply unit for inputting a commercial AC power and converting the power factor to a DC power compensated output; A pulse width control unit for inputting the DC power of the power supply unit, including a triangular wave generating unit and a comparator, and switching the input DC power by a pulse width modulation method; A DC-DC converter unit for inputting the switched power output from the pulse width control unit and converting the voltage into a voltage having a level for driving the LED lamp; The pulse width is detected by converting the current output from the DC-DC converter unit into a constant current and outputting the current output from the output current smoothing unit and the output current smoothing unit to the LED lamp, and amplifying and compensating an error with the current setting signal. And a dimming control unit for feeding back to the control unit.

The power supply unit inputs the AC power and blocks the noise signal to stabilize the noise filter in one step; An overvoltage cut-off unit which blocks the input of a voltage higher than an allowable reference voltage of the AC power source and stabilizes it in two stages; And a bridge rectifier for inputting the stabilized AC power, full-wave rectifying and outputting the DC power to the bridge circuit, and an active power factor compensator for inputting the DC power and actively compensating and outputting the power factor.

An inductor (L) having one end and the other end of the output current smoothing unit, the one end of which is connected to one end of the output side of the DC-DC converter unit; A first capacitor (C1) having one end and the other end and having one end connected to the other end of the inductor; A second capacitor C2 and a second capacitor C2 having one end and the other end and connected to a node to which the inductor and the first capacitor are connected, the other end of the second capacitor C2, and the DC -The other end of the DC converter section includes a resistor (R) for connecting one end to the node to be connected and the other end to the LED lamp.

The dimming control unit may include a current measuring unit detecting an output current output by the output current smoothing unit; A current-voltage converter configured to input a current output by the current measurement unit, convert the current into a voltage, and output the converted voltage; A synthesizer for inputting and synthesizing a current setting signal consisting of a voltage and a pulse waveform output by the current-voltage converter and outputting a difference value, and amplifying and compensating a difference value output by the combiner to a comparator input terminal of the pulse width control unit. It includes an amplification and compensation unit for outputting.

According to an exemplary embodiment of the present invention, the flicker phenomenon does not occur in the LED lamp even in the case of low current while controlling the brightness by adjusting the waveform of the current supplied to the LED lamp.

1 is a functional configuration of the LED lamp smart dimming converter device according to an embodiment of the present invention,
2 is a detailed functional configuration diagram of a power supply unit constituting the LED lamp smart dimming converter device according to an embodiment of the present invention,
3 is a detailed functional configuration diagram of a pulse width control unit, an output current smoothing unit, and a dimming control unit according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated in the drawings and described in detail in the detailed description. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all transformations, equivalents, and substitutes included in the spirit and scope of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

The power factor in an AC power system is defined as the percentage of power that can actually be used, which is defined as a numeric value between 0 and 1 and can be expressed as a percentage value.

Since a low power factor consumes a lot of current, all devices that use electricity need a high power factor. In other words, if the same device and the power factor is high, the current consumption is low and the maintenance cost is low.

Power factor compensator is a device that compensates for high power factor of low power factor, passive type and active type, passive type is fixed power factor value, active type is automatically adjusted power factor value for input power. to be.

1 is a functional configuration of the LED lamp smart dimming converter device according to an embodiment of the present invention.

Hereinafter, the LED lamp smart dimming converter device 1000 will be described in detail with reference to the accompanying drawings. The power supply unit 1100, the pulse width control unit 1200, the DC-DC (Dish-Dish) converter unit 1300, and output current smoothing are described. The unit 1400, the LED lamp 1500 and the dimming control unit 1600 is included.

The power supply 1100 inputs commercial AC power, stabilizes by blocking noise and overvoltage, and then converts the signal to DC through full wave rectification and actively compensates for the power factor. Detailed configuration of the power supply 1100 will be described again with reference to the accompanying drawings below.

The pulse width control unit 1200 inputs a DC power supply from the power supply unit 1100, and controls a phase of a triangular wave to output a DC current switched to a selected width. The phase of the triangular wave is automatically adjusted in a predetermined range by a control signal fed back from the dimming controller 1600 as a difference voltage. That is, the pulse width control unit 1200 adjusts the magnitude (quantity) of the direct current and outputs it.

The DC-DC converter unit 1300 converts a DC voltage input from the pulse width control unit 1200 into a DC of a higher or lower voltage and outputs the DC voltage. It is called a DC-DC converter. Since the LED constituting the LED light 1500 is driven at 3.3 volts (V), the DC-DC converter 1300 converts the DC voltage input from the pulse width control unit 1200 to a DC voltage of 3.3 volts. DC conversion and output.

The output current smoothing unit 1400 inputs a direct current from the DC-DC converter 1300 and smoothes the constant current at a constant level, and includes an inductor, a capacitor, and a resistor. The waveform of the current may be severely distorted in the process of converting the DC voltage by the DC-DC converter 1300.

When a direct current with a small waveform and a small amount of current is supplied to the LED lamp 1500, the flicker phenomenon is mainly caused by the LED lamp 1500. That is, the output current smoothing unit 1400 smoothly smoothes the current waveform of the DC input from the DC-DC converter 1300 and then outputs the LED to the LED light 1500.

The LED lamp 1500 includes an LED 1502 that emits light with high brightness by a direct current input from the output current smoothing unit 1400. The LED 1502 generates light by a DC driving voltage of 3.3 volts (V). The LEDs 1502 may be connected in parallel, in series, or in a state where the parallel and serial overlap.

The dimming controller 1600 detects the current output from the output current smoothing unit 1400, converts it into a voltage, extracts an error value that is a difference value by combining with a current setting signal, and amplifies and compensates the extracted difference value to obtain a pulse width control unit. To 1200. The current setting signal may be 3.3 volts (V), which is a reference operating voltage at which the LED (150) emitting light with high brightness is driven, and is a pulse waveform signal.

The dimming controller 1600 amplifies and compensates the detected difference voltage with an OP amp and feeds it back to the pulse width controller 1200. Here, the pulse width controller adjusts the width of the output current in the direction in which the value of the feedback difference voltage decreases. Therefore, the DC voltage output from the pulse width control unit 1200 maintains a constant level.

The LED 1502 constituting the LED light 1500 adjusts the amount of current supplied so that the brightness can be adjusted. In other words, increasing the amount of current emits light brightly, and decreasing the amount of current reduces brightness. As an example, if the current output from the pulse width controller 1200 is 10% or less of the current required by the LED lamp, the flicker phenomenon may occur in the LED lamp 1500.

When the flicker phenomenon occurs in the LED light 1500, the output current smoothing unit 1400 smoothes the waveform of the DC current input to the LED light so that the flicker phenomenon may not occur.

In the smart dimming converter device 1000 having such a configuration, the pulse width control unit 1200 receives a direct current from the power supply unit 1100 and outputs a discontinuous direct current by the switching control. It converts to a driving voltage, and the output current smoothing unit 1400 smoothly outputs a waveform of current so that the flicker phenomenon does not occur in the LED light 1500.

2 is a detailed functional configuration of a power supply unit constituting the LED lamp smart dimming converter device according to an embodiment of the present invention.

Hereinafter, the power supply unit 1100 will be described in detail with reference to the accompanying drawings. The power supply unit 1100 includes a noise filter 1110, an overvoltage blocking unit 1120, a bridge rectifying unit 1130, and an active power factor compensating unit.

The noise filter 1110 removes noise included in commercial AC power input. Commercial power is generally 60 Hz, and frequencies above 60 Hz are noise and need to be cut off and removed. The noise filter 1110 may form a ferrite material in a circular shape and configure the input power line.

The overvoltage blocking unit 1120 blocks input of a high overvoltage higher than a rated voltage allowed for commercial AC power through an input power line. As an example, an overvoltage may be a lightning strike, and may be introduced from an external source through a power line, and such an overvoltage may destroy a corresponding electric or electronic device connected to the power line in an unrecoverable state.

The bridge rectifying unit 1130 uses a rectifying diode to convert AC into direct current by full-wave rectifying AC. The connection state of the bridge circuit using the rectifying diode is shown in the figure.

The active power factor compensator 1140 actively compensates for the power factor of the commercial power source input to the power source 1100. The active power factor compensator 1140 automatically adjusts the capacitance of the capacitor according to the power of the input power to automatically compensate for the maximum power factor. . It is desirable to actively compensate for the power factor value to be 0.9 or more.

3 is a detailed functional configuration diagram of a pulse width control unit, an output current smoothing unit, and a dimming control unit according to an embodiment of the present invention.

Hereinafter, the pulse width control unit 1200 includes a triangular wave generator 1210 and a comparator 1220, and the output current smoothing unit 1400 includes an inductor L, first and first electrodes. 2 capacitors (C1, C2) and resistor (R). The dimming controller 1600 includes a current measuring unit 1610, a current voltage converting unit 1620, a combining unit 1630, and an amplifying and compensating unit 1640.

The pulse width controller 1200 generates a triangular wave at the triangular wave generator 1210 and outputs the triangular wave to one input terminal of the comparator 1220, and inputs a signal output from the dimming controller 1600 to the other input terminal of the comparator 1220. The pulse width control unit 1200 outputs a DC of a constant level. The output terminal of the power supply unit 1100 is connected to the other input terminal of the comparator 1220.

The output current smoothing unit 1400 connects the inductor L in series between the positive terminal of the DC-DC converter 1300 and the positive terminal of the LED lamp 1500, and the DC-DC converter. A resistor R is connected in series between the negative terminal of the negative unit 1300 and the negative terminal of the LED lamp 1500.

The first capacitor is connected between a node connected to the positive terminal of the inductor L and the LED lamp 1500 and a node connected to the DC-DC converter 1300 and the resistor R. FIG. The C1 and the second capacitor C2 are connected in parallel.

The output current smoothing unit 1400 smoothly smoothes the waveform of the output current.

The dimming controller 1600 detects a current output from the output current smoothing unit 1400, converts the detected current into a voltage, and combines the converted voltage with a current setting signal as a reference to detect a difference value. The detected difference value is amplified and compensated and fed back to the pulse width control unit 1200. Therefore, the dimming controller 1600 causes the pulse width controller 1200 to output a DC of a constant level.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art.

1000: LED Light Smart Dimming Converter Device
1100: power supply unit 1110: noise filter
1120: overvoltage cutout 1130: bridge rectifier
1140: active power factor correction unit 1200: pulse width control unit
1210: triangle wave generator 1220: comparator
1300: DC-DC converter section 1400: output current smoothing section
1500: LED light fixture 1502: LED
1600: dimming controller 1610: current measuring unit
1620: current voltage conversion unit 1630: synthesis unit
1640: amplification and compensation unit L: inductor
C1, C2: first and second capacitor R: resistor

Claims (4)

In the smart dimming converter device for adjusting the brightness of the LED light,
A power supply unit for inputting a commercial AC power source and converting the power source into a DC power source with a power factor correction;
A pulse width control unit for inputting the DC power of the power supply unit, including a triangular wave generating unit and a comparator, and switching the input DC power by a pulse width modulation method;
A DC-DC converter unit for inputting the switched power output from the pulse width control unit and converting the voltage into a voltage having a level for driving the LED lamp;
An output current smoothing unit converting the current output by the DC-DC converter unit into a constant current and outputting the constant current to the LED lamp; And
A dimming control unit for detecting a current output from the output current smoothing unit, amplifying and compensating an error with a current setting signal, and returning it to the pulse width control unit; Smart dimming converter device comprising a.
The method of claim 1,
The power supply unit,
A noise filter which inputs the AC power and blocks the noise signal to stabilize in one step;
An overvoltage cut-off unit which blocks the input of a voltage higher than an allowable reference voltage of the AC power source and stabilizes it in two stages;
A bridge rectifying unit for inputting the stabilized AC power, full-wave rectifying it to a bridge circuit, and outputting the DC power; And
An active power factor correction unit configured to input the DC power and actively compensate and output the power factor; Smart dimming converter device comprising a.
The method of claim 1,
The output current smoothing unit,
An inductor having one end and the other end and having one end connected to an output end of the DC-DC converter;
A first capacitor (C1) having one end and the other end and having one end connected to the other end of the inductor;
A second capacitor (C2) having one end and the other end and the one end connected to a node to which the inductor and the first capacitor are connected; And
And a resistor (R) for connecting one end to a node connected to the other end of the first capacitor (C1), the other end of the second capacitor (C2), and the other end of the output side of the DC-DC converter unit, and the other end of which is connected to an LED lamp. Smart dimming converter device made by.
The method of claim 1,
The dimming control unit,
A current measuring unit detecting an output current output by the output current smoothing unit;
A current-voltage converter configured to input a current output by the current measurement unit, convert the current into a voltage, and output the converted voltage;
A synthesizer which inputs and synthesizes a current setting signal having a voltage and a pulse waveform output by the current-voltage converter and outputs a difference value; And
An amplifying and compensating unit for amplifying and compensating a difference value output by the synthesizing unit and outputting it to the comparator input terminal of the pulse width control unit; Smart dimming converter device comprising a.

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