KR101028460B1 - Power supply for driving power led using microcontroller - Google Patents

Abstract

According to the present invention, a power supply for driving a power LED can be compactly configured, and by controlling a plurality of converters using a microcontroller, the brightness of the lighting device using the power LED can be varied in various ways and the life of the power LED can be extended. And enables remote control.

 Power LED driving power supply using a microcontroller according to the present invention, in driving a lighting device arranged a plurality of power LED, the rectifier circuit unit 210 for converting into a DC voltage supplied with commercial AC power; A power factor improvement DC-DC converter 220 for improving power factor reduction of the input power output from the rectifier circuit part; A main DC-DC converter 230 for converting the power factor-improved power source; N power LED series lines (240) coupled in parallel with said main DC-DC converter, said series lines having a plurality of said power LEDs coupled in series; N current-limiting DC-DC converters (251,... 25N) connected in series to the N power LED series lines to independently limit the power LED driving current flowing through each of the N power LED series lines; And a microcontroller for simultaneously and independently controlling the power factor improving DC-DC converter, the main DC-DC converter, and the N current limiting DC-DC converters.

 Power, LED, Drive, Converter, Microcontroller

Description

Power supply for power LED driving using microcontrollers {POWER SUPPLY FOR DRIVING POWER LED USING MICROCONTROLLER}

The present invention relates to a power supply, and more particularly, to a power supply for driving a power LED using a microcontroller.

LEDs are more environmentally friendly than conventional light sources, have high energy efficiency, and have a long service life. Therefore, many systems have recently been developed to apply LEDs to the lighting field. .

However, the power LED has a problem that heat is generated in the semiconductor junction when it is turned on, and to solve this problem, it is necessary to include a function to control the current supplied to the power LED, which is overlooked in most power LED lighting systems. As a result, the power LED lamp does not operate after a while since installation. Recently, in order to solve this problem, a system for adding a constant current control circuit to the rear of a conventional power supply is being released.

1 is an overall block diagram of a power LED driving power supply device according to the prior art, the rectifier circuit unit 110 for supplying a stable DC drive voltage to the power LED by receiving commercial AC power, input by the semiconductor switching operation Power factor correction converter 120 (PFC: Power Factor Corrector) for improving power factor reduction, the first control circuit unit 125 for controlling switching of the switching element in the power factor correction converter, power factor improved voltage The main DC-DC converter 130 for converting the DC voltage, the second control circuit 135 for controlling the switching of the switching elements in the DC-DC converter, the power LED device group 140 arranged in N series lines ), N current limiting converters 151, ..., 15N for respectively controlling the power LED driving currents arranged in N series lines, and N switching devices for controlling the switching elements in the N current limiting converters.And third to (N + 2) control circuit portions 161, ..., 16N.

As a result, the power supply device for driving a power LED according to the prior art includes three types of converters: a power factor improving converter 120, a main DC-DC converter 130, and a current limiting converter 151, ..., 15N. Is applied.

However, according to the prior art, a control circuit unit for controlling each converter is provided separately. In addition, the power LED lamp according to the prior art is configured by connecting a plurality of power LEDs, that is, six or twelve in series to form a single serial line, and then connect the plurality of such serial lines in parallel to form a whole lamp. A separate current limiting circuit is provided for each series line. Therefore, the control circuit part of the current limiting converter as many as the series line is provided separately to operate.

Therefore, the following problems exist in the power supply for driving a power LED according to the prior art.

First, since each control circuit part requires a power supply voltage for the control power supply, a large number of power supply voltages for the control power supply are generated, thereby increasing the power generator. Second, since the integrated control is not possible when changing the luminance in the lighting device using the power LED, for example, when reducing the luminance by 50%, only some predetermined serial lines should be turned off. As a result, the remaining power LEDs continue to turn on, and thus shorten the lifespan. Third, since each converter is individually controlled through a plurality of control circuits, it is difficult to variously change the brightness of the lighting device using the power LED. Fourth, since each converter is individually controlled through a plurality of control circuits, remote control using a communication function is impossible.

In order to solve the above problems, an object of the present invention is to compactly configure a power supply for driving a power LED.

In addition, another object of the present invention is to vary the luminance of a lighting device using a power LED by controlling a plurality of converters using a microcontroller.

In addition, another object of the present invention to extend the life of the power LED by integrated control of a plurality of converters using a microcontroller.

In addition, another object of the present invention is to enable a remote control since the integrated control of a plurality of converters using a microcontroller.

Power LED driving power supply using a microcontroller according to the present invention, in driving a lighting device arranged a plurality of power LED, the rectifier circuit unit 210 for converting into a DC voltage supplied with commercial AC power; A power factor improvement DC-DC converter 220 for improving power factor reduction of the input power output from the rectifier circuit part; A main DC-DC converter 230 for converting the power factor-improved power source; N power LED series lines (240) coupled in parallel with said main DC-DC converter, said series lines having a plurality of said power LEDs coupled in series; N current-limiting DC-DC converters (251,... 25N) connected in series to the N power LED series lines to independently limit the power LED driving current flowing through each of the N power LED series lines; And a microcontroller for simultaneously and independently controlling the power factor improving DC-DC converter, the main DC-DC converter, and the N current limiting DC-DC converters.

Preferably, the microcontroller converts an analog signal in the form of voltage or current output from the power factor improving DC-DC converter, the main DC-DC converter, and the N current limiting DC-DC converters into a digital signal. An A / D converter 430 to perform the same; An A / D channel selector 420 for selecting any one of a plurality of channels in the A / D converter; An arithmetic processor 410 for generating a switching control signal using the digital signal input through the A / D channel selector; And a switching waveform generator 440 for generating a switching waveform using the switching control signal output from the calculation processor.

Preferably, the A / D converter 430 includes: an A / D channel # 1 431 for receiving feedback from the output voltage of the power factor improving DC-DC converter 220; An A / D channel # 2 432 for receiving feedback from the output voltage of the main DC-DC converter 230; And A / D channels # 3 to (N + 2) 433, ..., 43 (N + 2) for receiving feedback of the output currents of the N current-limiting DC-DC converters 251 to 25N. )).

Preferably, the switching waveform generator 440 is a first PWM waveform generator 441 for outputting a PWM control signal having a fixed frequency and a variable ratio by using a switching control signal output from the calculation processor. ); A PFM waveform generator 442 for outputting a PFM control signal having a variable frequency and ratio by using a switching control signal output from the calculation processor; And second to (N + 1) PWM waveform generators 443, ..., 44 (N + 1) in which each on / off time point is controlled synchronously or asynchronously using the switching control signal output from the operation processor. )).

Advantageously, a power LED series line that remains turned off to satisfy the illuminance value required by the lighting device may be time-divisionally selected for the N power LED series lines.

Preferably, the power LED serial line is arranged in a number more than the number required for the rated luminance of the lighting device, and the power LED serial line is maintained in a turn-off state to satisfy the illuminance value required by the lighting device. It can be selected time-divisionally for the power LED series line.

According to the present invention, the power supply for driving the power LED can be compactly configured, and the luminance of the lighting device using the power LED can be variously changed by integrating and controlling a plurality of converters using a microcontroller. The power LED can be freely switched to extend the life of the power LED, and remote control can be performed using a microcontroller. Therefore, the brightness can be freely controlled remotely.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms or words used in the specification and claims should not be construed as having a conventional or dictionary meaning, and the inventors should properly explain the concept of terms in order to best explain their own invention. Based on the principle that can be defined, it should be interpreted as meaning and concept corresponding to the technical idea of the present invention. Therefore, the embodiments described in the specification and the drawings shown in the drawings are only one of the most preferred embodiments of the present invention and do not represent all of the technical idea of the present invention, various modifications that can be replaced at the time of the present application It should be understood that there may be equivalents and variations.

2 is an overall block diagram of a power supply for driving a power LED according to the present invention.

Power LED driving power supply device according to the present invention, the rectifier circuit 210 for supplying a stable DC drive voltage to the power LED by receiving a commercial AC power, to improve the power factor reduction of the input power by the semiconductor switching operation Step-up DC-DC converter 220 for power factor improvement, main DC-DC converter 230 for converting a power factor-improved voltage into a DC voltage having an appropriate potential, and a group of power LED elements 240 arranged in N series lines. ), N current limiting step-down DC-DC converters 251, ..., 25N for controlling the driving current of power LEDs arranged in N series lines, step-up DC-DC converter for power factor improvement, And a microcontroller 200 for simultaneously and independently controlling the main DC-DC converter and N current limiting step-down DC-DC converters.

Here, the microcontroller 200 according to an embodiment of the present invention can be controlled remotely.

3 is a waveform diagram of a driving control signal for driving a power LED according to an exemplary embodiment of the present invention.

The microcontroller 200 according to an embodiment of the present invention provides a pulse width modulation (PWM) waveform having a fixed frequency and variable duty ratio in the boost type DC-DC converter 220 for power factor improvement. In addition, the main DC-DC converter 230 provides a pulse frequency modulation (PFM) waveform of varying frequency and rate, and the five current limiting step-down DC-DC converters 251, ..., and 255 are on. Provides a pulse width modulation (PWM) waveform in which the off point is controlled synchronously or asynchronously.

Here, the main DC-DC converter 230 according to an embodiment of the present invention uses a PFM waveform because it uses a resonant converter. That is, if the main DC-DC converter according to another embodiment of the present invention is not a resonance type, a PWM waveform may be used.

4 is a block diagram of a microcontroller 200 according to an embodiment of the present invention.

The microcontroller 200 according to an embodiment of the present invention is an A / D converter 430, A / D for converting an analog signal in the form of voltage or current output from a plurality of DC-DC converter into a digital signal An A / D channel selector 420 for selecting any one of a plurality of channels in the converter, an arithmetic processor 410 for generating a switching control signal using a digital signal input through the A / D channel selector, And a switching waveform generator 440 for generating a switching waveform by using the switching control signal output from the operation processor.

A / D converter 430 according to an embodiment of the present invention is the A / D channel # 1 (431), the main DC-DC for receiving feedback of the output voltage of the step-up DC-DC converter 220 for power factor improvement A / D channel # 2 432 for receiving feedback of the output voltage of the converter 230, and A / D channel for receiving feedback of the output current of the step-down DC-DC converter 251, ... 25N for current limiting. # 3-(N + 2) (433, ..., 43 (N + 2)).

In addition, the switching waveform generator 440 according to an embodiment of the present invention is configured to output a PWM control signal having a fixed frequency and variable duty ratio by using a switching control signal output from the operation processor. 1 PWM waveform generator 441, PFM waveform generator 442 for outputting a PFM control signal of varying frequency and ratio using a switching control signal output from the calculation processor, and switching control output from the calculation processor And second to (N + 1) PWM waveform generators 443, ..., 44 (N + 1) in which each on / off time point is controlled synchronously or asynchronously using the signal.

Further, according to one embodiment of the present invention, N power LED serial lines may be arranged as many as necessary for the rated luminance required for the lighting device. For example, a total of four power LED series lines can be arranged for rated brightness. Thus, if 100% brightness is required for the lighting device, all four power LEDF series lines are turned on.

By the way, when the luminance of 75% is required, the turn-on state is maintained for three of the four power LED series lines and the turn-off state for one power LED series line. At this time, one power LED series line that maintains the turn-off state is alternately selected from four. For example, the power LED of the first series line is turned off for the first 10 minutes, the power LED of the second series line for the second 10 minutes, the power LED of the third series line for the third 10 minutes, During the fourth 10 minutes, the power LED of the fourth series line is turned off. After that, the above process is repeated.

In addition, if a luminance of 50% is required from the illuminance value detected by the illuminance sensor attached to the inside or outside of the lighting device, two of the four series lines are turned on and the two series lines are turned on. Keep it off. At this time, the two serial lines maintaining the turn-off state are alternately selected from the two serial lines as in the above. Here, the method of selecting two series lines out of four series lines is sufficient to maximize the life of the power LED. For example, the first and second series lines may be turned off for the first 10 minutes, and the third and fourth series lines may be turned off for the second 10 minutes.

Alternatively, a temperature sensor can be attached to each series line of the lighting device to turn off the series line with the lowest and lowest temperature values every 10 minutes.

Further, according to another embodiment of the present invention, the N power LED series lines may be arranged in a predetermined number more than the number required for the rated luminance required for the lighting device. For example, if four power LED series lines are required for rated brightness, one series line can be added to place five power LED series lines. If 100% brightness is required for the thus arranged lighting device, four of the five power LED series lines are turned on and one of the power LED series lines is turned off. . At this time, one power LED series line that maintains the turn-off state is alternately selected from five. For example, the power LED of the first series line is turned off for the first 10 minutes, the power LED of the second series line for the second 10 minutes, the power LED of the third series line for the third 10 minutes, The power LED of the fourth series line is turned off for the fourth 10 minutes and the power LED of the fifth series line is turned off for the fifth 10 minutes. After that, the above process is repeated.

In addition, if 75% luminance is required from the illuminance value detected by an illuminance sensor attached to the inside or outside of the lighting device, three of the five series lines are turned on and two series lines are turned on. Keep it off. At this time, the two series lines which maintain the turn-off state are alternately selected from five, as above. Here, the method of selecting two series lines out of five series lines is sufficient to maximize the life of the power LED. For example, the first and second serial lines for the first 10 minutes, the third and fourth serial lines for the second 10 minutes, the fifth and first serial lines for the third 10 minutes, and the fourth 10 For minutes, a method of keeping the second and third serial lines turned off may be used.

Alternatively, a temperature sensor can be attached to each series line of the lighting device to turn off the series line with the lowest and lowest temperature values every 10 minutes.

In addition, if a luminance of 50% is required from the illuminance value detected by the illuminance sensor attached to the inside or outside of the lighting device, two of the five series lines are turned on and three series lines are turned on. Keeping off, but selecting two of the five series lines to be turned on, is sufficient to maximize the life of the power LED.

In addition, if 25% of the luminance is required from the illuminance value detected by the illuminance sensor attached to the inside or outside of the lighting device, one of the five series lines is turned on and the four series lines are turned on. Keep it off. At this time, one series line which maintains the turn-on state is alternately selected from five, as above.

As described above, although the present invention has been described by way of limited embodiments and drawings, the present invention is not limited thereto and is intended by those skilled in the art to which the present invention pertains. Various modifications and variations are possible within the scope of equivalents of the claims to be described.

1 is an overall block diagram of a power supply for driving a power LED according to the prior art;

2 is an overall block diagram of a power supply for driving a power LED according to the present invention;

3 is a waveform diagram of a drive control signal for driving a power LED according to an embodiment of the present invention; and

4 is a block diagram of a microcontroller 200 according to an embodiment of the present invention.

* Brief description of the main symbols in the drawings *

210: rectifier circuit 220: step-up DC-DC converter for power factor improvement

230: main DC-DC converter 240: step-down DC-DC converter for current limiting

200: microcontroller

Claims (6)

In driving a lighting device in which a plurality of power LEDs are arranged, Rectifying circuit unit 210 for receiving a commercial AC power to convert into a DC voltage; A power factor improvement DC-DC converter 220 for improving power factor reduction of the input power output from the rectifier circuit part; A main DC-DC converter 230 for converting the power factor-improved power source; N power LED series lines (240) coupled in parallel with said main DC-DC converter, said series lines having a plurality of said power LEDs coupled in series; N current-limiting DC-DC converters (251,... 25N) connected in series to the N power LED series lines to independently limit the power LED driving current flowing through each of the N power LED series lines; And A microcontroller for simultaneously and independently controlling the power factor improving DC-DC converter, the main DC-DC converter, and N current limiting DC-DC converters. Power LED driving power supply using a microcontroller comprising a. The method of claim 1, wherein the microcontroller, A / D converter 430 for converting an analog signal in the form of voltage or current output from the power factor improving DC-DC converter, the main DC-DC converter, and the N current-limiting DC-DC converters into a digital signal 430. ); An A / D channel selector 420 for selecting any one of a plurality of channels in the A / D converter; An arithmetic processor 410 for generating a switching control signal using the digital signal input through the A / D channel selector; And Switching waveform generator 440 for generating a switching waveform by using the switching control signal output from the calculation processing unit Power LED driving power supply using a microcontroller comprising a. The method of claim 2, wherein the A / D converter 430, An A / D channel # 1 431 for receiving feedback from the output voltage of the power factor improving DC-DC converter 220; An A / D channel # 2 432 for receiving feedback from the output voltage of the main DC-DC converter 230; And A / D channels # 3 to (N + 2) (433, ..., 43 (N + 2) for receiving feedback of the output currents of the N current-limiting DC-DC converters 251 to 25N ) Power LED driving power supply using a microcontroller comprising a. The method of claim 2, wherein the switching waveform generator 440, A first PWM waveform generator 441 for outputting a PWM control signal having a fixed frequency and a variable ratio by using a switching control signal output from the calculation processor; A PFM waveform generator 442 for outputting a PFM control signal having a variable frequency and ratio by using a switching control signal output from the calculation processor; And Second to (N + 1) PWM waveform generators 443, ..., 44 (N + 1) in which each on / off time point is controlled synchronously or asynchronously using the switching control signal output from the arithmetic processing unit. ) Power LED driving power supply using a microcontroller comprising a. The method of claim 1, Power LED driving power source using a microcontroller, characterized in that the power LED series line is maintained in the turn-off state to satisfy the illuminance value required by the lighting device is selected time-divisionally with respect to the N power LED series line. Feeding device. The method of claim 1, The power LED serial line is arranged to be larger than the required number for the rated luminance of the lighting device, and maintains the turn-off state to satisfy the illuminance value required by the lighting device. Power supply for driving a power LED using a microcontroller, characterized in that time-selected with respect to.

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