WO2015070361A1

WO2015070361A1 - Led illuminating device using multiphase alternating current power supply

Info

Publication number: WO2015070361A1
Application number: PCT/CN2013/001392
Authority: WO
Inventors: 朱弘琦; 沈毓仁
Original assignee: 钰瀚科技股份有限公司
Priority date: 2013-11-15
Filing date: 2013-11-15
Publication date: 2015-05-21

Abstract

An LED illuminating device using multiphase alternating current (AC) power supply, and using alternating voltages of a plurality of different phases to reduce flickering; the illuminating device comprises a multiphase AC-to-AC power generator (220) generating alternating voltage of a plurality of different phases from the AC power supply, and a plurality of rectifiers (201-20N) connected to the alternating voltages of different phases to generate a plurality of rectified alternating voltages and supply power for a plurality of LED illuminating units. The illuminance of each LED illuminating unit varies with the input voltage, and reaches the maximum illuminance at different times due to different phases of the rectified alternating voltages, lowering variation between peak values of total illuminance of the illuminating device, thus also reducing flickering due to the LED illuminating device.

Description

Illuminating device for light-emitting diodes using multi-phase AC power supply

The present invention relates to light-emitting diode (LED)-based lighting devices, and more particularly to a driving device and method for a light-emitting diode-based lighting device for reducing light flicker. Background technique

The light-emitting diode (LED) is a semiconductor-based light source that is often used in low-power meters and home appliances. The use of light-emitting diodes has become more common in a variety of lighting devices. For example, high-brightness LEDs have been widely used in traffic lights, vehicle lights, and brake lights. In recent years, lighting devices using high voltage LED strings have also been developed to replace conventional white heat bulbs and fluorescent bulbs.

In order to increase the brightness of the light-emitting diode-based lighting device, a plurality of light-emitting diodes are usually connected in series to form a light-emitting diode-based lighting unit, and a plurality of light-emitting diode-based lighting units can be further connected in series to form an illumination. Device. The operating voltage required for each illuminator is usually determined by the forward voltage of the LEDs in the lighting unit, how many LEDs are in each lighting unit, how each lighting unit is connected to each other, and each How the lighting unit receives the voltage from the power source in the lighting device.

Therefore, in most applications, some type of supply voltage conversion device is required to convert a generally more common high voltage power supply to a lower voltage for providing one or more LED-based lighting units. . Since such a voltage conversion device is required, the efficiency of the lighting device based on the light emitting diode is reduced, the cost is increased, and it is difficult to reduce the volume thereof.

In order to improve the efficiency and reduce the size of LED-based lighting devices, many techniques have been developed to enable LED-based lighting devices to use alternating current such as 120V or 240V without the need for a voltage conversion device. In general, a light-emitting diode in a light-emitting diode-based illumination device is divided into a plurality of light-emitting diode segments. Each LED segment can be selectively slammed and turned off as the AC voltage increases or decreases under the control of the associated switch or current source. All switches or current sources in the luminaire are controlled by a controller.

Figure 1 shows a conventional LED-based lighting power supply for LED-based lighting In the block diagram, the AC voltage is rectified by the rectifier 1 to produce a rectified AC voltage, and the illumination unit 101 of an LED receives the rectified AC voltage as an input voltage.

Such a light-emitting diode-based lighting device has a simple structure and can be produced at a low price. However, since the input AC voltage is not stably adjusted, the brightness of the illumination unit of the LED changes with the input voltage, so that the LED-based illumination device has a strong light flash. In order to replace the traditional white heat bulbs and fluorescent bulbs with LED-based lighting devices, it has become an indispensable requirement for how to reduce the light flicker. Summary of the invention

The present invention provides a low-light-emitting LED-based illumination device. Therefore, the LED-based illumination device of the present invention supplies power from a rectified multi-phase AC voltage, thereby reducing variations in peak-to-peak brightness of the illumination device. .

In a first embodiment of the present invention, an LED-based illumination device includes an AC power source, a multi-phase AC to AC power generator that generates a plurality of AC voltages of different phases, for rectifying the plurality of different phases The AC voltage is a plurality of rectifiers, and a plurality of LED lighting units. The brightness of each of the LED lighting units varies with input voltage, and the plurality of rectified AC voltages of different phases provide power to the plurality of LED lighting units.

In a second embodiment of the present invention, an LED-based illumination device includes an AC power source, a multi-phase AC to AC power generator that generates a plurality of AC voltages of different phases, and a plurality of LED AC drive units. The brightness of each of the light emitting diode AC drive units varies as a function of the input voltage, and the plurality of different phase AC voltages provide power to the plurality of light emitting diode AC drive units.

In a third embodiment of the present invention, an LED-based illumination device includes an AC power source, a multi-phase AC power generator that generates a plurality of AC-to-AC voltages of different phases for rectifying the plurality of different phases. The AC voltage is a plurality of rectifiers, and the LED lighting unit. The brightness of the LED lighting unit varies with input voltage, and the plurality of rectified AC voltages of different phases are connected in parallel to each other to provide power to the LED lighting unit. DRAWINGS 1 shows a block diagram of a conventional LED-based illumination device powered by an AC voltage source;

2 shows a block diagram of an LED-based illumination device including a multi-phase AC to AC power generator in accordance with a first embodiment of the present invention;

3 shows an example of an LED lighting unit in the first embodiment;

4 shows a block diagram of an LED-based illumination device utilizing two alternating voltages of different phases, in accordance with a first embodiment of the present invention;

5A is a diagram showing voltage values of alternating current voltages of two phases in the LED-based lighting device of FIG. 4;

Figure 5B shows the voltage value of the rectified two-phase AC voltage;

6 shows a block diagram of an LED-based illumination device utilizing three different phase AC voltages, in accordance with a first embodiment of the present invention;

7A is a diagram showing the voltage value of the three-phase AC voltage in the LED-based lighting device of FIG. 6;

Figure 7B shows the voltage value of the rectified three-phase AC voltage;

Figure 8 shows the brightness of the three LED lighting units in Figure 6, as the three-phase AC voltage changes;

Figure 9 compares the brightness of an LED lighting unit with a single-phase AC voltage as the power source, and the brightness of the LED lighting device with three LED lighting units powered by a three-phase AC voltage;

Figure 10 shows a crest factor of an LED-based illumination device powered by single-phase, two-phase, and three-phase AC voltages in accordance with the present invention;

Figure 1 1 shows a block diagram of an LED-based illumination device including a multi-phase AC to AC power generator in accordance with a second embodiment of the present invention;

Figure 12 is a block diagram of an LED-based illumination device utilizing three different phases of AC-compression, in accordance with a second embodiment of the present invention;

Figure 13 shows a block diagram of an LED-based lighting fixture S comprising a multi-phase AC to AC power generator in accordance with a third embodiment of the present invention;

Figure 14 is a block diagram showing an example of an LED-based illumination device utilizing three different phases of alternating voltage, in accordance with a third embodiment of the present invention; 15A is a diagram showing voltage values of three-phase AC voltages in the LED-based lighting device of FIG. 14;

Figure 15B shows the voltage value of the rectified three-phase AC voltage;

Figure 16 is a comparison of the crest factor of a light-emitting diode-based lighting device according to the first embodiment and the third embodiment;

Figure 17 shows an example where there are N different phases of AC voltage that are directly connected to N rectifiers instead of using multiphase AC to AC power generators to generate AC voltages of different phases.

The reference numerals are as follows:

101, 201, 20N, 401, 402 LED lighting unit

1 10, 21 1, 21N, 41 1, 412 rectifier

220 multi-phase AC to AC power generator

341, 342, 34N LED segments

351, 352, 35N voltage controlled current limiters with three terminals

371, 37k LED segment

381, 38k voltage-controlled current limiter with three terminals

390 current source

420 quarter phase AC to AC power generator

601, 602, 603 LED lighting unit

61 1, 612, 613 rectifier

620 three-phase AC to AC power generator

1 101, 1 let, 1201, 1202, 1203 LED AC drive unit

1 120 multi-phase AC to AC power generator

1220 three-phase AC to AC power generator

1301, 1401, 1701 LED lighting unit

131 1, 131N, 141 1, 1412, 1413, 171 1, 171N rectifier

1320 Multiphase AC to AC Power Generator

1420 three-phase AC to AC power production k device specific implementation The present invention is further understood by the accompanying drawings, and the drawings also form a part of this specification. The drawings illustrate embodiments of the invention and, together with

2 shows a block diagram of an LED-based illumination device that utilizes multiple AC voltages of different phases to reduce light flicker in accordance with a first embodiment of the present invention. In this embodiment, the apparatus includes a multi-phase AC power generator 220, a plurality of rectifiers 21 1 - 21N, and a plurality of LED lighting units 201-20N. The multi-phase AC to AC power generator 220 generates a plurality of AC voltages from an AC power source, each AC voltage having a different phase, and the different phases may be a uniform or non-uniform distribution. Each AC voltage is supplied to a LED lighting unit via a rectifier to produce a rectified AC voltage.

Figure 3 shows an example of the LED lighting unit of Figure 2. The LED illumination unit includes a first plurality of LEDs divided into a plurality of LED segments 341-34N, each LED segment having a positive terminal and a negative terminal, each connected to a leading LED segment The negative terminal and the positive terminal of a subsequent LED segment. As shown in FIG. 3, the negative ends of each of the LED segments are also respectively connected to a first connection end of a voltage-controlled current limiter 351-35N having three terminals, and the second connection end of the current limiter A bias voltage V _r V _N is applied, and the third connection is connected to a common node in the LED lighting unit.

As can be seen from FIG. 3, the LED lighting unit further includes a second plurality of LEDs connected between the common node and the current source 390. The second plurality of LEDs are separated into a plurality of LEDs. Diode segments 371-37k. For simplicity of explanation, each LED segment shows only one LED, and a plurality of voltage controlled current limiters 381 - 38k having three terminals are connected in parallel with the plurality of LED segments 371 - 37k. Each of the voltage-controlled current limiters having two terminals has a first terminal connected to the opposite end of the LED segment: the first terminal is applied with a bias voltage V^-V^, and The three terminals are then connected to the first end of current source 390.

Fig. 4 shows an example made in accordance with a first embodiment of the present invention in which - one quarter of a phase is used to AC power to generate an alternating voltage having a phase difference of 90 degrees. The two-phase AC voltage is connected to two rectifiers 41 1 and 412, respectively, and then the rectified two-phase AC voltage is connected to the two LED lighting units 401 and 402, respectively.

Figure 5A shows the electric value of the two-phase AC voltage from a single-phase 220V AC power supply in the device of Figure 4, and Figure 5B shows the rectified two-phase 220V AC voltage. Pressure value. As shown in FIG. 4, in the example of the first embodiment, the two LED lighting units 401 and 402 are respectively connected to the rectified two alternating voltages whose phases are different by 90 degrees.

Fig. 6 shows an alternative example made in accordance with a first embodiment of the present invention in which a three phase AC to AC power generator 620 is utilized to generate a two phase AC voltage. The three-phase AC voltage is connected to three rectifiers 61 1, 612 and 613, respectively, and then the rectified three-phase AC voltage is connected to three LED lighting units 601, 602 and 603, respectively.

Fig. 7A shows the voltage value of the three-phase AC voltage generated by a single-phase 220V AC power source, and Fig. 7B shows the voltage value of the rectified three-phase 220V AC voltage. As shown in Fig. 6, in the example of the first embodiment, three LED lighting units 601, 602 and 603 are respectively connected to three rectified 220V alternating voltages of different phases.

Figure 8 shows the brightness of three LED lighting units powered by the rectified three-phase AC voltage of Figure 7B, the brightness of each LED lighting unit varying with the rectified AC voltage. Because the three rectified AC voltages have different phases, the brightness of each LED illumination unit reaches its highest value at different times. In the present invention, the total brightness of the light-emitting diode illumination device of the first embodiment, the sum of the brightness of each of the light-emitting diode illumination units, so that the change in the peak value of the total brightness is reduced, and the light flicker of the illumination device is also reduced.

Fig. 9 compares the luminance of an LED lighting unit powered by a single-phase AC voltage, and the luminance of the LED lighting apparatus of the first embodiment in which the rectified three-phase AC voltage is used as a power source in the present invention. It can be seen from Fig. 9 that the change between the peak value of the brightness of the LED lighting device with the rectified three-phase AC voltage as the power source is very much higher than that of the LED lighting unit with the single-phase AC voltage as the power source. Obviously small.

The crest factor is often used as an index of light flicker, and in order to express a reduction in flashing of the lamp, the present invention is studied in the LED lighting device of the first embodiment. The crest factor is defined as the ratio of the peak value to the rms value of the light produced by an illumination device. Figure 10 shows a light-emitting diode-based power supply based on rectified single-phase, two-phase, and three-phase AC 3⁄4 voltages. The crest factor of the lighting device.

As can be seen from Fig. 10, the peak W of the LED-based illumination device using the rectified two-phase and two-phase AC voltages is significantly lower. The peak of the LED-based lighting device with a rectified three-phase AC voltage as the power source is very close to the filament bulb. Crest of an LED-based illuminator powered by a rectified single-phase AC voltage Because, it is higher than the mouth light. Figure 10 also shows an LED lighting unit, how the crest factor varies with the number of LED segments.

1 shows a block diagram of an LED-based illumination device that utilizes multiple AC voltages of different phases to reduce light flicker in accordance with a second embodiment of the present invention. In this second embodiment, the apparatus includes a multi-phase AC to AC power generator 1 120, and a plurality of LED AC drive units 1 101 - 1 10N. The multi-phase AC to AC power generator 1 120 generates a plurality of AC voltages from an AC power source, each AC voltage having a different phase, and the different phases may be a uniform or uneven distribution. Each AC voltage is directly connected to a light-emitting diode AC drive unit whose brightness varies with input voltage.

Fig. 12 shows an example made in accordance with a second embodiment of the present invention in which a three-phase AC to AC power generator 1220 is utilized to generate a three-phase AC voltage. The three-phase AC voltage is respectively connected to three LED AC drive units 1201, 1202 and 1203, each LED AC drive unit, comprising at least one set of LEDs connected in series, and another set of LEDs connected in series in reverse. Two sets of LEDs connected in series are connected in parallel with each other.

To simplify the description, Figure 12 shows that each of the LED AC drive units contains only two inverted LEDs connected in parallel with each other. As can be seen from Figure 12, each of the LED AC drive units has an LED that is conductive regardless of whether the AC voltage is positive or negative.

Figure 13 shows a block diagram of an LED-based illumination device utilizing multiple AC voltages of different phases to reduce light flicker in accordance with a third embodiment of the present invention. In this third embodiment, the apparatus includes a multi-phase AC to AC power generator 1320, a plurality of rectifiers

131 1 - 131N , and an LED lighting unit 1301. The multi-phase AC to AC power generator 1320 generates a plurality of AC voltages from an AC power source, each AC voltage having a different phase, and the different phases may be a uniform or non-uniform distribution. Each of the AC voltages generates a rectified AC voltage via a -rectifier, and all of the rectified AC voltages of different phases are supplied in parallel to each other to supply power to the LED lighting unit 1301.

According to the present invention, the LED lighting unit shown in Fig. 3 can also be applied to the third embodiment. As shown in FIG. 13, all of the rectified AC voltages of different phases are connected in parallel to each other and to the LED lighting unit 1301. Fig. 14 1 shows an example made in accordance with a third embodiment of the present invention in which a three-phase AC to AC power generator 1420 is utilized to generate a three-phase AC voltage. The three-phase AC voltage is connected to two rectifiers 141 1, 1412 and 1413, respectively. The rectified three-phase AC voltage - f is then connected in parallel to the LED lighting unit

1401.

Fig. 15A shows the two-phase AC to AC power generator 1420, a two-phase AC voltage generated by a single-phase 220V AC power source. Figure 15B shows the voltage value of the rectified single phase 220V AC voltage, and the voltage value of the rectified three phase AC voltage applied to the LED lighting unit 1401. The gang has three rectified 220V AC voltages connected in different phases to form a rectified two-phase 220V AC voltage, a voltage applied to the LED lighting unit 1401, and an individual absolute voltage value of the rectified 220V AC voltage of different phases. The maximum value. Therefore, the variation between the peak values of the voltage values is lowered, so that the light flicker of the LED lighting unit is also reduced.

16 shows a crest factor of an LED-based illumination device that supplies power with a rectified three-phase AC voltage according to the first embodiment and the third embodiment, wherein the crest factor is based on a light-emitting diode in the illumination device The number of segments is displayed. As can be seen from Fig. 16, the crest factor of the illumination device of the third embodiment is lower than that of the first embodiment.

It is worth mentioning that, in the above-mentioned embodiments, although a plurality of AC voltages of different phases are generated by a multi-phase AC to an AC power generator from a single-phase AC power source, Where a plurality of AC voltages of different phases are already available, they can be rectified directly via the rectifier without the need to utilize multi-phase AC to AC power generators.

For example, in Figure 17, there are already N different phase AC voltages, phase-1 to phase-N, directly connected to the N rectifiers 171 1-171N instead of using multi-phase AC to AC power generators. To produce. All of the rectified multi-phase AC voltages are connected in parallel to each other and to the light-emitting diode lighting unit 1701.

Although the invention has been described above by way of a few embodiments, it is obvious to those skilled in the art that many modifications and modifications may be made without departing from the invention as defined below. Within the scope of the patent application.

Claims

Rights request

1. A lighting device for a light emitting diode using a multi-phase AC power source, comprising: a plurality of alternating voltages of different phases;

a plurality of rectifiers each connected to the plurality of different phase AC voltages to generate a plurality of rectified AC voltages;

A plurality of light emitting diode illumination units are each coupled to said plurality of rectified AC voltages; wherein a brightness of each of said plurality of LED illumination units changes with an input voltage.

The lighting device according to claim 1, wherein the plurality of different phase AC voltages are uniformly distributed in phase.

The illumination device according to claim 1, wherein the plurality of different phase AC voltages have a phase that is unevenly distributed.

The lighting device of claim 1, further comprising:

An AC power source;

A multi-phase AC to AC power generator is coupled to the AC power source to generate the AC voltages of the plurality of different phases.

The lighting device according to claim 4, wherein said multi-phase AC to AC power generator comprises a quarter phase AC to AC power generator, and said plurality of different phase AC voltages comprise two An alternating voltage with a phase difference of 90 degrees.

The lighting device according to claim 4, wherein said multi-phase AC to AC power generator comprises a three-phase AC to AC power generator.

The illuminating device according to claim 1, wherein each of the plurality of LED lighting units comprises:

The first plurality of light emitting diodes are divided into a plurality of light emitting diode segments, wherein each of the light emitting diode segments has a positive terminal and a ^ terminal;

a first plurality of voltage controlled current limiters having three terminals, wherein each of the voltage controlled current limiters having three terminals is associated with one of the first plurality of light emitting diode segments Correspondingly, the first connection end is connected to the negative end of the corresponding LED segment, the second connection end is connected with a bias voltage, and the second connection end is connected to the LED a first co-question node in the lighting unit;

The second plurality of light emitting diodes are divided into a second plurality of light emitting diode segments, wherein each of the light emitting diode segments has a positive terminal and a negative terminal, wherein a positive end of the first LED segment is connected to the first a common node, the negative end of the last LED segment is connected to a second common node in the LED lighting unit;

a second plurality of voltage controlled current limiters having three terminals, wherein each of the voltage controlled current limiters having three terminals corresponds to one of the second plurality of light emitting diode segments And having a first connection end connected to a positive end of its corresponding LED segment, a second connection end connection is applied with a bias voltage, and a third connection end is connected to the second common node;

A current source has a first end connected to the second common node and a second end grounded.

8. A light-emitting diode-based lighting device, comprising:

a plurality of alternating voltages of different phases;

a plurality of light emitting diode alternating voltage driving units are each connected to the alternating voltages of the plurality of different phases;

The brightness of each of the plurality of light emitting diode alternating voltage driving units of the light emitting diode alternating voltage driving unit changes with the input voltage.

The lighting device according to claim 8, wherein the plurality of different phase AC voltages are uniformly distributed in phase.

The lighting device according to claim 8, wherein the plurality of different phase AC voltages have a phase that is unevenly distributed.

The lighting device according to claim 8, further comprising:

An AC power source;

12. The illumination device of claim 1 , wherein the multi-phase AC to AC power generator comprises a quarter phase AC to AC power generator, and wherein the plurality of AC voltages of different phases comprise Two AC voltages with a phase difference of 90 degrees.

The lighting device according to claim 11, wherein the multi-phase AC to AC power generator comprises a three-phase AC power source.

The illuminating device according to claim 8, wherein each of the plurality of light emitting diode alternating voltage driving units comprises at least two sets of opposite light emitting diodes connected in parallel with each other, wherein each group The light emitting diode comprises one or more light emitting diodes in one or in series.

15. A light-emitting diode-based lighting device, comprising:

a plurality of alternating voltages of different phases;

a plurality of rectifiers each connected to the plurality of different phase AC voltages to generate a plurality of rectified AC voltages, the plurality of rectified AC voltages being connected in parallel with each other;

An LED lighting unit is coupled to the plurality of rectified AC voltages; wherein the brightness of the LED lighting unit changes with an input voltage.

The illuminating device according to claim 15, wherein the plurality of alternating voltages of different phases have phases uniformly distributed.

The lighting device according to claim 15, wherein the plurality of alternating voltages of different phases have phases that are unevenly distributed.

The lighting device of claim 15, further comprising:

An AC power source;

- A multi-phase AC to AC power generator is coupled to the AC power source to generate the AC voltages of the plurality of different phases.

19. The illumination device of claim 18, wherein said multi-phase AC to AC power generator comprises a quarter phase AC to AC power generator, and wherein said plurality of different phase AC voltages comprise two An alternating voltage with a phase difference of 90 degrees.

The illumination device according to claim 18, wherein said multi-phase AC to AC power generator comprises a three-phase AC to AC power generator.

The lighting device of claim 15, wherein the LED lighting unit comprises:

The first plurality of light emitting diodes are divided into a plurality of groups of light emitting diode segments, wherein the 毎-light emitting diode segments have - a positive terminal and a - a negative terminal;

a first plurality of voltage controlled current limiters having three terminals, wherein each of the voltage controlled current limiters having three terminals corresponds to one of the first plurality of light emitting diode segments And have a negative connection of the -connector to its corresponding LED segment a second connection end is applied with a bias voltage, and the second connection end is connected to the first common node in the LED illumination unit;

The second plurality of light emitting diodes are separated into a first plurality of light emitting diode segments, wherein each of the light emitting diode segments has a positive end and a negative end, wherein a positive end of the first LED segment is connected to the first common node The negative end of the last LED segment is connected to a second common node in the LED lighting unit;