WO2009113784A2 - Led drive device - Google Patents

Abstract

The present invention concerns an LED drive device which is arranged in such a way as to be able to block leakage current and which is also arranged in such a way as to be able to smoothly drive the LED. The LED drive device of the present invention is one in which LED modules arrayed on a metal PCB are connected to a plurality of regular-power-source input lines, and it comprises cut-off elements which are respectively provided on all of the input lines of the LED modules connected to the plurality of regular-power-source input lines and which are for cutting off the regular-power-source input to all of the input lines of the LED modules. When switched off, both sides of the regular-power-source input line are turned off. Consequently, in principle, there is no scope to produce any leakage current since there is no way that an electrical potential could be generated in the circuit layer (copper foil) of the metal PCB. More specifically, when it is switched off, the LED module (alternating-current LED module) is immediately turned off and thus not only can operational reliability be ensured but also unnecessary power loss is prevented.

Description

LED drive

The present invention relates to an LED driving device, and more particularly, to an apparatus for efficiently driving an LED used as a light source of a luminaire.

A configuration of an LED luminaire for directly applying a commercial power source (eg, AC 220V) to an LED module is shown in FIG. 1. An LED module in which a plurality of LEDs D1 to DN are arrayed in series is connected to a commercial power supply input line (AC input). One of the two commercial power input lines is directly connected to one end of the LED module. The other commercial power input line is connected to the other end of the LED module via the switch 50. The LED module is arrayed in a metal PCB (PCB) 20. In FIG. 1, reference numeral 10 denotes a heat sink grounded at the bottom of the metal PC 20, reference numeral 30 denotes an insulating layer made of epoxy, and reference numeral 40 denotes a copper layer on which a circuit pattern is formed. .

As such, a typical LED luminaire that directly applies commercial power to the LED module is turned on / off through a switch 50 installed only on one of two commercial power input lines.

However, when the switch 50 is turned off, the plurality of LEDs D1 to DN are not turned off immediately but are lightly turned on for a predetermined time. That is, although the switch 50 is turned off, a current is leaked to the ground GND through the metal PC 20 and the heat sink 10, and a plurality of LEDs D1 to DN are found to be finely lit. It was. In other words, as a result of measuring the leakage waveform by installing an oscillator between the base or heat sink 10 of the LED module and ground (GND), it was confirmed that about 140 Vrms (200 V peak) of about 60 Hz frequency was measured.

As a result of identifying the cause of leakage current, it was found that the metal PC 20 plays the role of a capacitor. That is, the metal PC 20 is basically composed of a base layer 22 and a circuit layer 24 (copper) and a dielectric layer 26 interposed between the base layer 22 and the circuit layer 24 as shown in FIG. do. Here, since the base layer 22 and the circuit layer 24 serve as electrodes, and the intermediate dielectric layer 26 acts as a dielectric, the metal PC 20 has a capacitor structure. Capacitors have a characteristic of capacitive impedance and microleakage occurs due to the use of AC voltage in the withstand voltage test. In particular, it has been found that the leakage current increases in proportion to the area of the opposite electrode of the capacitor.

Therefore, the conventional LED luminaire having the switch 50 installed only in one of two commercial power supply input lines is difficult to guarantee the reliability of operation due to leakage current. That is, even though the switch 50 is turned off, the LEDs D1 to DN are lightly turned on, making it difficult to guarantee the reliability of the operation and causing unnecessary power loss.

In addition, all loads using a commercial power source, such as an AC LED luminaire, generate a leakage of power consumption when switched off for AC power application. 3 is a circuit diagram illustrating a power consumption leak in a conventional switch-off.

When the switch SW is turned on, a closed circuit is formed between the power supply stage 54 and the load 56 so that a commercial power supply (alternating current) from the power supply stage 54 is mostly loaded through the triac 52. Is applied.

However, when the switch SW is turned off, there is a minute current flow in the direction of the arrow "a". That is, when the switch SW is off, the current is transferred to the load 56 through the gate of the triac 52 instead of being completely insulated from the triac 52.

As described above, when the switch SW is turned off in the AC LED luminaire, a loss of standby power occurs due to the generation of minute leakage current. In addition, when a part of the body inadvertently contacts the load 56 in a state where a minute leakage current is not provided to the load 56 when the switch SW is turned off, an electric shock may occur. That is, in the conventional AC LED luminaire, when the switch is off, the minute light is generated due to the generation of leakage current, it is difficult to ensure the reliability of the operation.

On the other hand, the method of controlling the LED (red LED 64, green LED 66, blue LED 68) used as a light source of the luminaire as shown in Figure 4 pulse width modulation to control the brightness by adjusting the pulse width (PWM: Pulse Width Modulation) is the most common method.

In a typical pulse width modulation method, a switching mode power supply (SMPS) unit 60 and a PWM controller 62 are required. The SMPS unit 60 converts the AC input power into a DC output voltage so as to match the operating power of the luminaire and outputs it. The PWM controller 62 is based on a control signal inputted with an amplitude of the input voltage in order to maintain a constant voltage or a constant current state at all times without a change in the output voltage due to a change in the input voltage (DC voltage) from the SMPS unit 60. Modulate the width of the pulse to a constant amplitude. The red LED 64, the green LED 66, and the blue LED 68 are driven by signals output from the PWM control unit 62.

Here, the SMPS unit 60 performs intermittent control at a high frequency by using a high-speed power semiconductor device and obtains various stable DC voltages through an internal rectifying circuit and a smoothing circuit. That is, the SMPS unit 60 should have various components internally, and in particular, it should have a high-speed power semiconductor device for switching.

However, when the switching frequency is increased, power loss is increased due to switching loss, inductor loss, and the like, and surge and noise are generated by switching. Accordingly, the SMPS unit 60 should be frequently replaced by causing frequent failures.

In addition, the connection state of a plurality of AC LEDs driven by receiving an AC commercial power is as illustrated in FIG. 5. As illustrated in FIG. 5, a plurality of AC LEDs L1 to L8 are connected in series and used as a light source.

In FIG. 5, when the plurality of AC LEDs L1 to L8 are all normal, when AC commercial power is applied from the power supply terminal Vcc, the plurality of AC LEDs L1 to L8 are all turned on to emit light.

However, when an open occurs in any one AC LED (L5 in FIG. 1), not only the corresponding LED is turned off but also all AC LEDs of the serial line are not lit.

For example, home appliances such as lighting fixtures, which are used as a light source, for example, an LED module having three to four LEDs connected in series, such as a home or office, requires a low voltage power supply (for example, a power supply of approximately 24V or less). . Luminaires that require a low-voltage power source must change their power source accordingly. For example, a converter capable of outputting a normal high voltage power may be used as it is, but the number of parts increases more than necessary, and the size of the transformer also increases, leading to increased manufacturing cost and lower reliability.

Accordingly, there is a growing need for a converter suitable for a luminaire requiring a low voltage power supply.

The present invention has been proposed to solve the above-described problems, and an object of the present invention is to provide an LED driving device capable of blocking leakage current and smoothly driving the LED.

That is, the present invention prevents leakage current caused by the characteristics of capacitors in the metal PCB in the LED luminaire employing the metal PCB, and does not cause loss due to leakage current even if the switch is turned off in the AC LED luminaire, Allows the user to drive the LED without using the AC power.Allows the other AC LEDs to light continuously even when one of the AC powers connected in series using the AC commercial power is opened. It is intended to be convertible to.

In order to achieve the above object, the LED driving device according to the preferred embodiment of the present invention is a device connected to a plurality of commercial power input line LED module arrayed in a metal PC,

It includes a blocking element is installed on all input lines of the LED module connected to the plurality of commercial power input lines, respectively, to block the commercial power input to all input lines of the LED module.

The interruption element is composed of an AC relay provided with a switch on each of the input lines of the semiconductor switching element or the LED module.

A bridge diode may be further included at the rear end of the blocking element, and a filter for blocking noise flowing into the input line of the LED module may be further included in the input line of the LED module.

An LED driving apparatus according to another embodiment of the present invention, the rectifier for rectifying the commercial power from the power supply stage; A first switching driver and a second switching driver driven on / off based on an output signal of the rectifier and including a photo triac; A first semiconductor switching element installed between the first switching driver and one end of the load and forming a power supply path between the power supply terminal and one end of the load as the first switching driver is turned on; And a second semiconductor switching element installed between the second switching driver and the other end of the load and forming a power supply path between the power supply terminal and the other end of the load as the second switching driver is turned on.

And a time constant portion for controlling phases of the first and second semiconductor switching elements.

The time constant section is provided between the power supply stage and the rectifying section, and includes a variable resistor and a capacitor.

According to still another aspect of the present invention, there is provided an LED driving device including: a first switching driver and a second switching driver including a photo triac, which are driven on / off based on an input signal; A first semiconductor switching element installed between the power supply terminal and one end of the load and forming a power supply path between the power supply terminal and one end of the load as the first switching driver is turned on; A second semiconductor switching element installed between the power supply terminal and the other end of the load and forming a power supply path between the power supply terminal and the other end of the load as the second switching driver is turned on; A phase sensing unit sensing a phase of an input external signal and outputting an AC signal corresponding thereto; And a rectifying unit rectifying the AC signal from the phase sensing unit and sending the rectified AC signal to the first switching driver and the second switching driver.

The external signal input to the phase sensing unit is input in the form of a PWM wave or a square wave.

LED driving apparatus according to another embodiment of the present invention, the rectifier for rectifying the commercial power from the power supply stage; A switching driver driven on / off based on an output signal of the rectifier and including a photo triac; A semiconductor switching element installed between the power supply terminal and one end of the load and forming a power supply path from the power supply terminal to the load as the switching driver is turned on; And a selection switch unit provided between the power supply terminal and both ends of the load, and switching off the switching driver by operation to cut off the power supply path from the power supply terminal to the load.

The semiconductor switching element includes a triac.

An LED driving device according to another embodiment of the present invention, a device for driving the LED,

A switching unit including a rectifier including a semiconductor switching element turned on / off according to an input control signal, and rectifying the input AC commercial power and outputting the rectified AC power to an LED; And a control unit generating a control signal for turning on / off the semiconductor switching element and outputting the control signal to the switching unit.

Semiconductor switching elements include thyristors or triacs.

The transformer unit further includes a transformer unit connected between the switching unit and the AC commercial power input terminal to drop the input AC commercial power to the switching unit.

The switching unit comprises: a first switching unit connected to the first secondary side of the transformer unit; And second and third switching units connected to the second secondary side of the transformer unit, wherein the number of coil windings on the first secondary side of the transformer unit is smaller than the number of coil windings on the second secondary side of the transformer unit.

According to another embodiment of the present invention, an LED driving device is a device having a unidirectional power supply passage path in which a plurality of AC LEDs receiving AC commercial power are connected in series.

A plurality of closed-circuit holding portions connected one to one to each of the plurality of alternating current LEDs,

Each of the plurality of closed-circuit holders may be electrically connected as the first AC switching element is turned on and the first semiconductor switching element is turned on when the corresponding AC LED is opened and the voltage applied to both ends is greater than or equal to a predetermined value. And a second semiconductor switching element.

The first semiconductor switching element is composed of a zener diode.

The second semiconductor switching element is composed of a silicon controlled rectifier (SCR) or a triac whose control stage is connected to one end of the zener diode.

According to another embodiment of the present invention, an LED driving device is a device having a bidirectional power passage path in which a plurality of pairs of AC LEDs receiving AC commercial power are arrayed.

A plurality of closed-circuit holding portions connected one to one to each of the pair of alternating LEDs,

Each of the plurality of closed-circuit holding portions is a semiconductor switching element that is electrically connected as one AC LED of a corresponding pair of AC LEDs is opened and the voltage applied to both ends thereof is greater than or equal to a predetermined value, thereby forming a power passage path.

The semiconductor switching element is composed of a sidak.

The semiconductor switching device is electrically connected as the first semiconductor switching device is turned on when one of the corresponding AC LEDs is opened and the voltage applied to both ends thereof is greater than or equal to a predetermined value, and the first semiconductor switching device is turned on. And a second semiconductor switching element for forming a power passage path.

The first semiconductor switching element consists of a first Zener diode and a second Zener diode connected between a corresponding pair of alternating LEDs.

The second semiconductor switching element is composed of a triac with a control terminal connected between the first zener diode and the second zener diode.

An LED drive device according to another embodiment of the present invention is a device for converting a commercial AC power source to a low-voltage AC power source for outputting,

A time constant element installed between both ends of the rectifier for rectifying the commercial AC power source, one end of which is connected to one end of the primary side of the transformer having a predetermined turns ratio together with one end of the rectifier; And one end of which is connected to the time constant element and the other end of which is connected to the other end of the primary side of the transformer having a predetermined turns ratio, and switching driven by an external PWM signal to output an oscillation signal for outputting a low voltage AC power of the transformer. Contains wealth.

The switching unit includes: a photo coupler driven on / off in accordance with the input PWM signal; And a switching device that switches according to the on / off driving of the photo coupler.

An LED drive device according to another embodiment of the present invention is a device for converting a commercial AC power source to a low-voltage AC power source for outputting,

A time constant element connected to an output end of the rectifying unit for rectifying commercial AC power and a primary side of a transformer having a predetermined winding ratio, and for performing variable time constant control; And a switching unit which is driven on / off according to a variable time constant in the time constant element and outputs an oscillation signal for outputting a low voltage AC power of the transformer.

The time constant element includes a variable resistor and is connected between the output end of the rectifier and the primary side of the transformer.

The switching unit includes a first switching element and a second switching element which are installed between the output other end of the time constant element and the rectifying unit and the primary side of the transformer, and whose control stage is connected to the time constant element, respectively.

According to the present invention having such a configuration, since both of the commercial power supply input lines are turned off at the time of switching off, potentials cannot be generated in the circuit layer (copper foil) of the metal PC, and thus, there is a possibility of blocking the possibility of leakage current. In other words, when the switch is turned off, the LED module (AC module) is immediately turned off, thereby obtaining operational reliability and preventing unnecessary power loss.

When the AC LED luminaire is switched off, the power path path to both ends of the load is completely blocked, thereby minimizing standby power loss and preventing electric shock. That is, the leakage current can be completely cut off when switching off the AC LED luminaire, thereby achieving an energy saving effect and increasing safety.

Implement the circuit for LED driving by rectifying AC commercial power directly with rectifier (consisting of thyristor, triac, etc.) or by rectifying the rectifier after voltage drop through transformer and directing DC power to LEDs (R, G, B). This is simple. In addition, since the SMPS is not used, the trouble of replacement due to frequent failures is eliminated. It does not use SMPS, so it is cost effective.

Instead of SMPS, which requires a lot of internal parts, the rectifier by thyristor or the like replaces the role of SMPS and AC switch, so it is possible to control the brightness of RGB LEDs by phase control rather than pulse width modulation method.

In addition, the efficiency is approximately 98% or more at rated power, resulting in less power loss compared to devices using conventional SMPS.

When a plurality of AC LEDs receiving AC commercial power are connected in series to have a one-way or two-way power passage path, when one of the AC LEDs is opened, a closed circuit is maintained through the break-over. This keeps the other alternating current LEDs on the serial line continuously lit.

Since there are not many circuit elements used to convert commercial AC power to low voltage AC power, it is very simple to implement the circuit and at low cost.

The output of the transformer can be easily controlled by the frequency and pulse width of the pulse width modulation (PWM) signal from the outside. In addition, when the AC LED is connected to the secondary side of the transformer or the AC LED is connected instead of the transformer, the dimming of the corresponding AC LED is possible by a pulse width modulation (PWM) signal from the outside.

The variable resistor makes it easy to control the output of the transformer. Even in this case, when the AC LED is connected to the secondary side of the transformer or the AC LED is connected instead of the transformer, dimming of the corresponding AC LED is possible with a variable resistor.

1 is a view adopted to explain the operation of the LED module of the conventional LED lamp.

2 is a view showing the basic structure of the metal PCB shown in FIG.

3 is a circuit diagram illustrating a power consumption leak in a conventional switch-off.

4 is a block diagram illustrating a conventional LED driving apparatus.

FIG. 5 is a diagram illustrating a problem that occurs when a plurality of LEDs, which are light sources of an LED module using AC commercial power, are connected in series.

6 is a circuit diagram of the LED driving apparatus according to the first embodiment of the present invention.

7 to 12 show detailed circuit examples for implementing the first embodiment of the present invention.

13 is a circuit diagram of the LED driving apparatus according to the second embodiment of the present invention.

14 is a circuit diagram of the LED driving apparatus according to the third embodiment of the present invention.

15 is a circuit diagram of the LED driving apparatus according to the fourth embodiment of the present invention.

16 is a circuit diagram of the LED driving apparatus according to the fifth embodiment of the present invention.

17 is a block diagram of an LED driving apparatus according to a sixth embodiment of the present invention.

18 is an internal circuit diagram of the block diagram of FIG. 17.

19 is a circuit diagram of the LED driving apparatus according to the seventh embodiment of the present invention.

Fig. 20 is a diagram in which the LED driving circuit of the eighth embodiment of the present invention is adopted in a line in which a plurality of LEDs are connected in series in a single direction.

Fig. 21 is a diagram in which the LED driving circuit of the eighth embodiment of the present invention is adopted in a line in which a plurality of LEDs are interconnected in both directions.

FIG. 22 is a diagram illustrating an example of a semiconductor switching element that can be employed in the closed circuit holding unit shown in FIG. 20.

FIG. 23 is a circuit diagram in which the semiconductor switching device of FIG. 22 is connected to a line in which a plurality of LEDs are connected in series in a single direction.

FIG. 24 is a diagram showing another example of the semiconductor switching element employable in the closed-circuit holding portion shown in FIG. 20.

25 and 26 show an example of a semiconductor switching element that can be employed in the closed-circuit holding portion shown in FIG. 21.

Fig. 27 is a circuit diagram of the LED driving apparatus according to the ninth embodiment of the present invention, and is a circuit diagram showing the configuration of a low voltage AC power converter.

Fig. 28 is a circuit diagram of the LED driving apparatus according to the tenth embodiment of the present invention, and shows a configuration of a low voltage AC power converter.

29 and 30 are waveform diagrams illustrating output signal waveforms of the circuit diagram of FIG. 28.

Hereinafter, an LED driving apparatus according to an embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 6 is a circuit diagram of the LED driving apparatus according to the first embodiment of the present invention, and more specifically, it may be viewed as a circuit diagram illustrating the concept of a device for completely blocking current leaking from the LED luminaire. The same components as in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted.

6, the switch 70a is installed at one of the two commercial power input lines, and the switch 70b is connected to the other commercial power input line. The installation is different. That is, in FIG. 6, blocking devices (that is, switches 70a and 70b) are respectively provided in the plurality of commercial power input lines, thereby turning on / off both of the commercial power input lines.

As shown in FIG. 6, when the switches 60a and 60b are turned off, the current path to the ground GND is cut off through the metal PC 20 so that the metal PC 20 generates a leakage current due to the capacitor characteristic. Shut off and avoid unnecessary power loss.

A detailed circuit configuration for implementing the first embodiment of the present invention will be described with reference to FIGS. 7 to 12.

Figure 7 is to control the two commercial power input line by using an AC relay.

The switches 70a and 70b of the AC relay are installed together with the plurality of LEDs in the LED module 80. Of course, only a plurality of LEDs may be referred to as the LED module 80, and the AC relay may be provided at the front end of the LED module 80. The switches 70a and 70b of the AC relay are installed in input lines (eg, two input lines) of the LED module 80 including a plurality of LEDs connected in series with each other. AC relay means a relay whose power of the input unit is AC. In FIG. 7, reference numeral 70 denotes a body of an AC relay connected to both input lines of the LED module 80. The body 70 of the ac relay includes a coil (not shown).

In FIG. 7, an AC relay may be understood to include a body 70 and switches 70a and 70b. Reference numeral 70 is referred to as the body of an AC relay, but is also commonly referred to as a relay.

In FIG. 7, the reference numerals are not given, but there is a resistance between the switches 70a and 70b and the LED module 80. The resistance prevents the LEDs from breaking due to overvoltage application. Regarding the resistance, the same applies to other examples described below. The switch 50 of FIG. 7 may be understood as a conventional power switch.

In the case of FIG. 7, when the switch 50 that is on is turned off, the switches 70a and 70b of the AC relay are turned off, so that input of commercial power to both input lines of the LED module 80 is blocked. As a result, no electric potential is generated in the circuit layer (copper foil) of the metal PC 20, and no leakage current is generated.

FIG. 8 is to control two commercial power supply input lines by using a semiconductor switching device (triac).

Triacs 90a and 90b are installed on input lines (eg, two input lines) of the LED module 80 including a plurality of LEDs connected in series with each other.

The triacs 90a and 90b are bidirectional three-terminal rectifiers and are mainly used for AC control. Triacs 90a and 90b each have two thyristors connected in parallel in the forward and reverse directions.

Although not shown in the drawings, a module for applying a signal for turning on (eg, a gate current) to the gates of the triacs 90a and 90b (in this module, applies a signal for turning off the triacs 90a and 90b). May be installed).

In FIG. 8, although not given a reference numeral, a resistor is provided between the triacs 90a and 90b and the plurality of LEDs. The resistance prevents the LEDs from breaking due to overvoltage application. The switch 50 of FIG. 8 may be understood as a conventional power switch.

In the case of FIG. 8, when the switch 50 that is on is turned off, the forward anode current of the thyristors of each of the triacs 90a and 90b that is on is lowered below the holding current. Of course, the turn-off signal is input to the gates of the triacs 90a and 90b when the switch 50 is turned off. Accordingly, the triacs 90a and 90b are turned off to cut off commercial power input to both input lines of the LED module 80. Therefore, no electric potential is generated in the circuit layer (copper foil) of the metal PC 20, so that no leakage current is generated.

In addition, in FIG. 8, since the triac is used as the blocking element, the on / off characteristic is superior to the AC relay. As a result, the circuit configuration of FIG. 8 enables faster operation control than the circuit configuration of FIG. 7.

9 is to control the two commercial power input line by using the AC relay and the bridge diode. 9 is a configuration in which the bridge diode 100 is added to the configuration of FIG. 7. In FIG. 9, the same elements as in FIG. 7 will be omitted.

The bridge diode 100 is provided at the rear end of the switches 70a and 70b of the AC relay. When the switch 50 is turned on, the bridge diode 100 receives a predetermined commercial power through an AC relay and converts it into a DC component. In other words, the AC power is converted into DC power by the bridge diode 100 to drive the LED module.

In the case of Fig. 9, when the switch 50 that is on is turned off, the switches 70a and 70b of the AC relay are turned off, so that input of commercial power to both input lines of the LED module 80 is blocked. As a result, no electric potential is generated in the circuit layer (copper foil) of the metal PC 20, and no leakage current is generated.

FIG. 10 is to control two commercial power input lines using a triac and a bridge diode. 10 is a configuration in which the bridge diode 100 is added to the configuration of FIG. 8. In FIG. 10, the same components as in FIG. 8 will be omitted.

The bridge diode 100 is provided at the rear ends of the triacs 90a and 90b.

FIG. 10 is a circuit for converting AC power into DC power by the bridge diode 100 to drive the LED module as shown in FIG. 9. In FIG. 10, since the triac is used, the on / off characteristic is superior to that of FIG. 9 using the AC relay. That is, the configuration of FIG. 10 enables faster operation control than the configuration of FIG. 9.

Although not shown in the drawings, a module for applying a signal for turning on (eg, a gate current) to the gates of the triacs 90a and 90b (in this module, applies a signal for turning off the triacs 90a and 90b). May be installed).

In the case of FIG. 10, when the switch 50 that is on is turned off, the forward anode current of each of the triacs 90a and 90b that is on is lowered below the holding current. Of course, the turn-off signal is input to the gates of the triacs 90a and 90b when the switch 50 is turned off. Accordingly, the triacs 90a and 90b are turned off to cut off commercial power input to both input lines of the LED module 80. Therefore, no electric potential is generated in the circuit layer (copper foil) of the metal PC 20, so that no leakage current is generated.

FIG. 11 is to control two commercial power input lines using the bridge thyristor 110. Bridge thyristor 110 is a bridge made of four thyristors.

The bridge thyristor 110 is installed at an input line of the LED module 80 including a plurality of LEDs connected in series.

Although not shown in the drawings, a module for applying a signal for turning on (eg, a gate current) to the gate of each thyristor of the bridge thyristor 110 (in this module, applies a signal for turning off the bridge thyristor 110). May be installed).

In the case of FIG. 11, when the switch 50 which is on is turned off, the forward anode current of the bridge thyristor 110 is lowered below the holding current. Of course, when the switch 50 is turned off, a turn-off signal is input to the gate of each thyristor of the bridge thyristor 110. Accordingly, the bridge thyristor 110 is turned off to block the commercial power input to both input lines of the LED module 80. Therefore, no electric potential is generated in the circuit layer (copper foil) of the metal PC 20, so that no leakage current is generated.

In FIG. 11, since the bridge thyristor 110 is used, the on / off characteristic is superior to FIG. 7 using the AC relay. That is, the configuration of FIG. 11 enables faster operation control than the configuration of FIG. 7.

FIG. 12 illustrates a configuration in which an EMI filter 120 is added to the configuration of FIG. 8. In FIG. 12, the same components as in FIG. 8 will be omitted.

The EMS filter 120 removes noise carried by commercial power input into the LED module 80. When the switch 50 is turned on, a predetermined commercial power source AC is input to the LED module 80 and the triacs 90a and 90b are turned on. At this time, the EM filter 120 in the LED module 80 removes the noise carried in the commercial power supply.

Although not shown in the drawings, a module for applying a signal for turning on (eg, a gate current) to the gates of the triacs 90a and 90b (in this module, applies a signal for turning off the triacs 90a and 90b). May be installed).

In the case of FIG. 12, when the switch 50 that is on is turned off, the forward anode current of each of the triacs 90a and 90b that is on is lowered below the holding current. Of course, the turn-off signal is input to the gates of the triacs 90a and 90b when the switch 50 is turned off. Accordingly, the triacs 90a and 90b are turned off to cut off commercial power input to both input lines of the LED module 80. Therefore, no electric potential is generated in the circuit layer (copper foil) of the metal PC 20, so that no leakage current is generated. In addition, FIG. 12 additionally obtains the noise removing effect by having the EM filter 120 more than FIG. 8.

(Second embodiment)

13 is a circuit diagram of the LED driving apparatus according to the second embodiment of the present invention. More specifically, it is a circuit diagram of the leakage current interruption device at the time of switching off in an AC LED luminaire.

In Fig. 13, reference numeral 122 denotes an input terminal (for example, two-wire type) to which a commercial power supply (alternating current) is input, hereinafter referred to as a power supply terminal for convenience. Reference numeral 124 denotes an output terminal (for example, two-wire type) connected to a load (not shown; for example, an LED), hereinafter referred to as a load for convenience.

The second embodiment includes a rectifier 126, a first switching driver 128, a second switching driver 130, a first semiconductor switching element Q1, and a second semiconductor switching element Q2.

The rectifier 126 rectifies the commercial power input through the power stage 122. For example, the rectifier 126 includes a bridge diode.

The first switching driver 128 is driven on / off based on the output signal (DC power supply) of the rectifier 126. For example, the first switching driver 128 includes a photo triac including a light emitting element and a light receiving element. That is, the first switching driver 128 is turned on as the light emitting device is turned on and emits light.

The second switching driver 130 is driven on / off based on the output signal (DC power supply) of the rectifier 126. For example, the second switching driver 130 includes a photo triac including a light emitting element and a light receiving element. That is, the second switching driver 130 is turned on as the light emitting device is turned on and emits light.

An anode of a light emitting element (eg, a light emitting diode) of the first switching driver 128 is connected to any connection portion of the rectifier 126. The cathode of the light emitting element (eg, a light emitting diode) of the first switching driver 128 is connected to the anode of the light emitting element (eg, a light emitting diode) of the second switching driver 130. The cathode of the light emitting element (eg, the light emitting diode) of the second switching driver 130 is connected to the other connection portion of the rectifier 126 through the resistor R3.

The first semiconductor switching element Q1 is installed between one end of the power supply stage 122 and one end of the load 124, and a control terminal (gate) is connected to the first switching driver 128. The first semiconductor switching element Q1 is turned on as the first switching driver 128 is turned on, so that the first semiconductor switching element Q1 turns on a power supply path (ie, a path through which current can flow) between the power supply 122 and one end of the load 124. Form. For example, the first semiconductor switching element Q1 comprises a triac.

The second semiconductor switching element Q2 is installed between the other end of the power supply stage 122 and the other end of the load 124, and a control terminal (gate) is connected to the second switching driver 130. The second semiconductor switching element Q2 is turned on as the second switching driver 130 is turned on, so that the second semiconductor switching element Q2 turns on a power supply path (ie, a path through which current can flow) between the power supply 122 and the other end of the load 124. Form. For example, the second semiconductor switching element Q2 comprises a triac.

Triacs as examples of the first and second semiconductor switching elements Q1 and Q2 are bidirectional three-terminal rectifying elements, which are mainly used for AC control. Triac is a structure in which two thyristors are connected in parallel in the forward and reverse directions, respectively.

In FIG. 13, the resistor R1 prevents damage of the light receiving element of the first switching driver 128 due to overvoltage application. The resistor R2 prevents damage of the light receiving element of the second switching driver 130 due to overvoltage application. The resistor R3 controls the current of the line in which the light emitting elements of the first and second switching drivers 128 and 130 and the rectifier 126 are connected to each other.

According to the second embodiment configured as described above, the commercial power (AC) input from the power supply stage 122 while the switch (not shown) is turned on is converted into direct current by the rectifier 126. The first and second switching drivers 128 and 130 are turned on by the signal of the DC component output from the rectifier 126. Accordingly, a predetermined AC signal is input to the gates of the first and second semiconductor switching elements Q1 and Q2 through the light receiving elements of the first and second switching drivers 128 and 130.

As a predetermined AC signal is inputted to the gates of the first and second semiconductor switching elements Q1 and Q2, the first and second semiconductor switching elements Q1 and Q2 are turned on to supply commercial power from the power stage 122. Is applied to the load 124.

On the contrary, when the commercial power input from the power supply stage 122 is blocked (off the switch (not shown)), the first and second switching drivers 128 and 130 are turned off. That is, since the light emitting element and the light receiving element of the first and second switching drivers 128 and 130 are completely insulated and the first and second semiconductor switching elements Q1 and Q2 are turned off, the potential at the load 124 is reduced. No level is generated and no leakage current is generated. Accordingly, fine lighting of a load (eg, a lamp, an LED, etc.) is not generated, thereby minimizing standby power loss, and preventing an electric shock due to inadvertent human contact when switching off.

(Third Embodiment)

14 is a circuit diagram of the LED driving apparatus according to the third embodiment of the present invention. More specifically, it is a circuit diagram of the leakage current interruption device at the time of switching off in an AC LED luminaire.

The third embodiment is almost the same as the configuration of the second embodiment, except that the time constant part 132 is further configured. In FIG. 14, the same reference numerals are assigned to the same elements in FIG. 13, and description thereof will be omitted.

The time constant 132 is installed between the power supply stage 122 and the rectifier 126. The time constant 132 controls the phases of the first and second semiconductor switching elements Q1 and Q2.

The time constant part 132 includes resistors R4 and R5 and a capacitor C connected in series with each other. Resistor R5 is a variable resistor. The node between the resistor R5 of the time constant portion 132 and the capacitor C is connected to any connection portion of the rectifier 126. In the case of the time constant part 132, when an AC signal is input to the capacitor C, the current is approximately 90 degrees out of phase with the voltage. Here, when the resistance value of the resistor R5 (variable resistor) is adjusted (for example, 0 (low resistance) to 90 (high resistance)), the phases of the first and second semiconductor switching elements Q1 and Q2 are adjusted. To control the output. Of course, when the resistance value of the resistor R5 is adjusted to the maximum, the first and second switching drivers 128 and 130 may be turned off to turn off the first and second semiconductor switching elements Q1 and Q2.

Since the operation of the third embodiment is substantially the same as the operation of the second embodiment except for the operation of the time constant unit 132, description thereof will be omitted. In addition, the effect of the third embodiment is controlled by the time constant part 132 (ie, the phases of the first and second semiconductor switching elements Q1 and Q2 at will) in addition to the effect of the second embodiment. So you can adjust the output to your liking).

(Example 4)

15 is a circuit diagram of the LED driving apparatus according to the fourth embodiment of the present invention. More specifically, it is a circuit diagram of the leakage current interruption device at the time of switching off in an AC LED luminaire.

Comparing the fourth embodiment to the above-described third embodiment, in the third embodiment, the time constant part 132 is connected to the power supply stage 122 so that the phases of the first and second semiconductor switching elements Q1 and Q2 are adjusted. To control. In the fourth exemplary embodiment, the phase sensing unit 134 senses a phase of an external signal (for example, a PWM wave or square wave type signal) input from the outside regardless of the power supply stage 122, and outputs a corresponding signal to the rectifier 126. To be sent to) is different from the third embodiment. The fourth embodiment is characterized in that the first and second semiconductor switching elements Q1 and Q2 can be turned on and off and the output can be converted by an external signal. In Fig. 15, reference numeral 134 denotes an input of an external signal. Receiving external signal input.

That is, the phase sensing unit 134 senses the phase of the input external signal to determine on / off timing points for the first and second semiconductor switching elements Q1 and Q2, and generates an AC signal corresponding thereto. To (126).

In FIG. 15, the same or similar components as those of the components of FIG. 13 or 14 are denoted by the same reference numerals, and description thereof will be omitted. That is, in FIG. 15, the rectifier 126, the first and second switching drivers 128 and 130, and the first and second semiconductor switching elements Q1 and Q2 are functionally equivalent to the corresponding components in FIG. 13 or 14. Works the same.

According to the fourth embodiment configured as described above, commercial power (AC) input from the power supply stage 122 is input to the first and second semiconductor switching elements Q1 and Q2. At this time, as the external signal is input to the external signal input terminal 134, the phase sensing unit 134 senses the phase of the input external signal. The phase sensing unit 134 determines on / off timing points of the first and second semiconductor switching elements Q1 and Q2, and then generates an AC signal corresponding thereto and sends it to the rectifier 126. The first and second switching drivers 128 and 130 are turned on / off by the signal of the DC component output from the rectifier 126.

When the first and second switching drivers 128 and 130 are turned on, the first and second semiconductor switching elements Q1 and Q2 are turned on, and commercial power from the power stage 122 is applied to the load 124.

On the contrary, when the first and second switching drivers 128 and 130 are turned off by an external signal meaning "0", the light emitting device and the light receiving device of the first and second switching drivers 128 and 130 are completely separated. Insulated and the first and second semiconductor switching elements Q1 and Q2 are turned off. As a result, the potential level does not occur in the load 124, so that no leakage current is generated. This prevents fine lighting of the load (eg, lamps, LEDs, etc.) from occurring, thereby minimizing standby power loss and preventing electric shock due to inadvertent human contact when the switch is turned off.

(Example 5)

16 is a circuit diagram of the LED driving apparatus according to the fifth embodiment of the present invention. More specifically, it is a circuit diagram of the leakage current interruption device at the time of switching off in an AC LED luminaire.

In the fifth embodiment, manually shutting off the power supply path by operating the selector switch 136 is different from the above embodiments.

The fifth embodiment includes a rectifier 126, a switching driver 140, a semiconductor switching element Q1, and a selection switch unit 136.

The rectifier 126 rectifies the commercial power input through the power stage 122 as in the above embodiments. The structure and function of the rectifier are the same as in the above embodiments, and the same reference numerals are used for the sake of convenience.

The switching driver 140 is driven on / off based on the output signal (DC power supply) of the rectifier 126. For example, the switching driver 140 includes a photo triac including a light emitting element and a light receiving element. That is, the switching driver 140 turns on the light receiving device as the light emitting device is turned on and emits light.

The semiconductor switching element Q1 is installed between one end of the power supply terminal 122 and one end of the load 124, and a control terminal (gate) is connected to the switching driver 140. The semiconductor switching element Q1 is turned on as the switching driver 140 is turned on to form a power supply path (that is, a path through which current can flow) between the power supply 122 and one end of the load 124. For example, semiconductor switching element Q1 includes a triac as in the previous embodiments. In FIG. 16, the reference numeral of the semiconductor switching element is referred to as Q1, which is provided at the same position as the first semiconductor switching element in the above-described embodiments and has the same reference numeral for convenience.

The selector switch 136 is installed between the power supply stage 122 and both ends of the load 124 at the front end of the rectifier 126. The selection switch unit 136 turns off the switching driver 140 by a user's manipulation to block the power supply path from the power supply stage 122 to the load 124. For example, the selection switch unit 136 is operated such that the switch SW is connected to the contacts 1 and 4 in the initial state (power on state), and the switch SW is connected to the contacts 3 and 6 in the power off state. It is operated to be connected to each. Such operation is performed by the user. That is, when it is confirmed that the load (for example, lamp, LED, etc.) is finely lit even though the power is off, the user operates the switch SW to be connected to the contacts 3 and 6.

In FIG. 16, reference numeral S denotes a power on / off switch connected to a commercial power supply line (not shown), and reference numeral 138 denotes a power supply stage 122 serving as a jack as an inlet connected to the switch S. Connected with Of course, the inlet 138 and the power supply stage 122 are not shown in FIG. 16, and the switch S and the selection switch unit 136 may be simply connected.

According to the fifth embodiment configured as described above, if the switch S is turned on and the switch SW of the selection switch unit 136 is connected to the contacts 1 and 4, the commercial power input from the power supply stage 122. (AC) is converted into DC by the rectifier 126. The switching driver 140 is turned on by the signal of the DC component output from the rectifier 126. Accordingly, a predetermined AC signal is input to the gate of the semiconductor switching element Q1 through the light receiving element of the switching driver 140.

As a predetermined AC signal is input to the gate of the semiconductor switching element Q1, the semiconductor switching element Q1 is turned on to apply commercial power from the power supply stage 122 to the load 124.

However, if the load 124 (eg, a lamp, an LED, etc.) is finely lit (that is, finely lit by leakage current) despite the need to turn off the switch S as necessary, the user may select the switch unit 136. By operating the switch (SW) of the existing contact state is changed. That is, when the switch S is in the on state, the switch SW is connected to the contacts 1 and 4, and when a fine lighting of the load is found when the switch S is turned off, the switch SW is connected to the contacts 3 and 6. Operate to be connected. In this case, the switching driver 140 is turned off. That is, since the light emitting element of the switching driver 140 and the light receiving element are completely insulated and the semiconductor switching element Q1 is turned off, the potential level does not occur in the load 124, and thus no leakage current is generated. This eliminates fine lighting of the load (eg, lamps, LEDs, etc.), thereby minimizing standby power loss and preventing electric shock due to inadvertent human contact when switching off.

(Sixth Embodiment)

17 is a block diagram of an LED driving apparatus according to a sixth embodiment of the present invention.

The sixth embodiment includes a switching unit 150 and a control unit 152.

The switching unit 150 is composed of a rectifier composed of a semiconductor switching element that is turned on / off according to the input control signal. The switching unit 150 rectifies the input AC commercial power and outputs the same to the red LED 154, the green LED 156, and the blue LED 158.

The controller 152 generates a control signal for turning on / off the semiconductor switching element and applies it to the switching unit 150.

18 is an internal circuit diagram of the block diagram of FIG. 17.

The switching unit 150 includes a first switching unit 150a, a second switching unit 150b, and a third switching unit 150c. The first to third switching portions 150a to 150c are each composed of four thyristors (rectifiers) coupled in a bridge form. In FIG. 18, the first to third switching units 150a to 150c are configured by using a thyristor, but a triac may be used if necessary. Here, the thyristor is referred to as an example of a semiconductor switching device. Thyristors in the first to third switching units 150a to 150c are turned on / off by a control signal (on / off signal) from the controller 152. In order to control the brightness of the LED, it is preferable that the thyristor in the first to third switching units 150a to 150c adopt a gate turn-off thyristor which can be turned off at a free timing.

The first switching unit 150a rectifies and transmits the AC commercial power provided from the AC commercial power terminals AC1 and AC2 to the red LED 154. The red LED 154 is composed of a plurality of red LEDs RD1 to RDN connected in series with each other. Here, the red LED 154 may be referred to as a red LED module.

The second switching unit 150b rectifies and transmits the AC commercial power provided from the AC commercial power stages AC1 and AC2 to the green LED 156. The green LED 156 is composed of a plurality of green LEDs GD1 to GDN connected in series with each other. Here, the green LED 156 may be referred to as a green LED module.

The third switching unit 150c rectifies and transmits the AC commercial power provided from the AC commercial power terminals AC1 and AC2 to the blue LED 158. The blue LED 158 is composed of a plurality of blue LEDs BD1 to BDN connected in series with each other. Here, the blue LED 158 may be referred to as a blue LED module.

In FIG. 18, the resistors R are installed in the red LEDs 154, the green LEDs 156, and the blue LEDs 158, respectively. Since constant current cannot be used in AC, a resistor (R) is used to control the current of the corresponding LED line.

In FIG. 18, the number of LEDs of the red LEDs 154 is approximately 1.5 times larger than the number of LEDs of the green LEDs 156 and the blue LEDs 158. In general, the voltage at both ends is about 2.1 to 2.4V when checking the power consumption of 1W (350mA) of the red LED when driving the LED RGB, and the voltage at both ends when checking the power consumption of 1W (350mA) of the green and blue LED is approximately. It is about 3.1 to 3.5V. When using a single power supply, the number of LEDs of the red LED 154 is adjusted to match the voltage of the blue LED and to equalize the power consumption of the red LED 154, the green LED 156, and the blue LED 158. The number of LEDs of the green LED 156 and the blue LED 158 is approximately 1.5 times greater.

Although not shown in FIGS. 17 and 18, for example, the switching unit 150 may further include a filter circuit for removing a surge component such as a transient peak current generated when an AC commercial power is applied.

In the sixth embodiment having the circuit configuration as shown in FIG. 18, the AC commercial power is directly converted into a direct current by the rectifier in the switching unit 150 and sent to the red LED 154, the green LED 156, and the blue LED 158. It becomes. At this time, the output power can be controlled by changing the phase by the timing of turning on the thyristor by using the thyristor element of the rectifier. Accordingly, the luminance control for the red LED 154, the green LED 156, and the blue LED 158 is possible.

This not only simplifies the circuit implementation for LED driving but also eliminates the need for SMPS, thus eliminating the hassle of replacement due to frequent failures.

It does not use SMPS, so it is cost effective. Instead of SMPS, which requires a lot of internal parts, the rectifier by thyristor or the like replaces the role of SMPS and AC switch, so it is possible to control the brightness of RGB LEDs by phase control rather than pulse width modulation method.

In addition, the efficiency is approximately 98% or more at rated power, resulting in less power loss compared to devices using conventional SMPS.

(Example 7)

19 is a circuit diagram of the LED driving apparatus according to the seventh embodiment of the present invention.

In the seventh embodiment, the transformer part is further provided in the configuration of FIG. 17 described above. Therefore, the block diagram for explaining the seventh embodiment is not shown separately, but instead the circuit diagram of FIG.

The seventh embodiment includes a transformer 160, a switching unit 150 (150a, 150b, 150c) and a controller 152.

The transformer 160 drops the AC commercial power input thereto.

The switching unit 150 is configured as a rectifier including a semiconductor switching element connected to the secondary side of the transformer unit 160 and turned on / off according to an input control signal. The switching unit 150 rectifies AC power from the secondary side of the transformer unit 160 and sends the rectified power to the red LED 154, the green LED 156, and the blue LED 158. The controller 152 performs the same function as the controller 152 described with reference to FIG. 17.

The switching unit 150 may include a first switching unit 150a connected to the first secondary side 5-9 of the transformer unit 160; And second and third switching units 150b and 150c connected to the second secondary side 8-10 of the transformer unit 160. An internal configuration of the first to third switching parts 150a to 150c of FIG. 19 is the same as that of the first to third switching parts 150a to 150c of FIG. 18.

The first switching unit 150a rectifies and transmits the AC power (which is a voltage drop AC power) from the first secondary side 5-9 of the transformer unit 160 to the red LED 154. The red LED 154 is composed of a plurality of red LEDs RD1 to RDN connected in series with each other. Here, the red LED 154 may be referred to as a red LED module.

The second switching unit 150b rectifies and transmits the AC power (which is the voltage-falling AC power) from the second secondary side 8-10 of the transformer unit 160 to the green LED 156. The green LED 156 is composed of a plurality of green LEDs GD1 to GDN connected in series with each other. Here, the green LED 156 may be referred to as a green LED module.

The third switching unit 150c rectifies and transmits the AC power supply (which is the voltage-falling AC power supply) from the second secondary side 8-10 of the transformer unit 160 to the blue LED 158. The blue LED 158 is composed of a plurality of blue LEDs BD1 to BDN connected in series with each other. Here, the blue LED 158 may be referred to as a blue LED module.

In FIG. 19, a resistor R is installed in each of the red LED 154, the green LED 156, and the blue LED 158. Since constant current cannot be used in AC, a resistor (R) is used to control the current of the corresponding LED line.

In FIG. 19, unlike in FIG. 18, the number of LEDs of the red LED 154, the green LED 156, and the blue LED 158 is the same. When checking the power consumption of 1W (350mA) level of red LED when driving LED RGB, voltage of both ends is about 2.1 ~ 2.4V, and voltage of both ends is about 3.1 ~ 3.5 when checking power consumption of 1W (350mA) level of green and blue LED. V is about. If 12 LEDs are used for each RGB, the red LED is about 25.2 to 28.8V, and the green and blue LEDs are about 37.2 to 42V. Since the blue LED and the green LED have similar power consumption, the same power source can be used, so that the second secondary side 8-10 of the transformer unit 160 is used together, and the red LED has a blue LED and a green LED at power consumption. Since it is different from the first secondary side 5-9 of the transformer unit 160.

Thus, in order to equalize the number of the red LEDs 154, the green LEDs 156, and the blue LEDs 158 with the same power consumption, the paths for supplying driving power to the red LEDs 154 are provided. The number of coil turns on the first secondary side 5-9 of the transformer unit 160 located is smaller than the number of coil turns on the second secondary side 8-10. That is, when the number of windings of the first secondary side coil and the second secondary side coil is the same and the number of LEDs in each of the RGB is the same, the power consumption of the green and blue LEDs is larger than that of the red LEDs. When the number of coil turns on the first secondary side 5-9 of 160 is smaller than the number of coil turns on the second secondary side 8-10 of the transformer 160, power consumption of each other becomes similar. This is because the voltage induced in the secondary coil is proportional to the number of turns of the secondary coil.

Here, the voltage excited on the first secondary side 5-9 and the voltage excited on the second secondary side 8-10 of the transformer 160 are determined by the number of series of LEDs. The number of coil turns (the number of turns) of the first secondary side 5-9 of the transformer unit 160 and the number of coil turns (the number of turns) of the second secondary side 8-10 correspond to the voltage determined for each. Will be decided.

In the seventh exemplary embodiment having the circuit configuration as shown in FIG. 19, the AC commercial power is first reduced in voltage by the transformer 160, and then converted into a DC by a rectifier in the switching unit 150. 156, to the blue LED 158. At this time, the output power can be controlled by changing the phase by the timing of turning on the thyristor by using the thyristor element of the rectifier. Accordingly, the luminance control for the red LED 154, the green LED 156, and the blue LED 158 is possible.

This not only simplifies the circuit implementation for LED driving but also eliminates the need for SMPS, thus eliminating the hassle of replacement due to frequent failures.

It does not use SMPS, so it is cost effective. Instead of SMPS, which requires a lot of internal parts, the rectifier by thyristor or the like replaces the role of SMPS and AC switch, so it is possible to control the brightness of RGB LEDs by phase control rather than pulse width modulation method.

In addition, the efficiency is approximately 98% or more at rated power, resulting in less power loss compared to devices using conventional SMPS.

(Example 8)

Fig. 20 is a diagram in which the LED driving circuit of the eighth embodiment of the present invention is adopted in a line in which a plurality of LEDs are connected in series in a single direction.

A plurality of AC LEDs LD1 to LD6 receiving AC commercial power are connected in series to each other to have a one-way power passage. One closed circuit holder is connected to each alternating LED. For example, the closed loop holding part 161 is connected between the anode and the cathode of the AC LED LD1. The closed loop holding part 162 is connected between the anode and the cathode of the AC LED LD2. The closed loop holding part 163 is connected between the anode and the cathode of the AC LED LD3. The closed loop holding part 164 is connected between the anode and the cathode of the AC LED LD4. The closed loop holding part 165 is connected between the anode and the cathode of the AC LED LD5. The closed loop holding part 166 is connected between the anode and the cathode of the AC LED LD6.

In FIG. 20, the number of alternating LEDs is expressed as six, but the number may be added or subtracted, and the number of closed circuit holding units is also correspondingly added or reduced according to the number of alternating LEDs.

Fig. 21 is a diagram in which the LED driving circuit of the eighth embodiment of the present invention is adopted in a line in which a plurality of LEDs are interconnected in both directions.

A pair of AC LEDs receiving AC commercial power is arrayed to form a bidirectional power passage. One closed loop holder is connected to the pair of AC LEDs. For example, the closed circuit holding unit 171 is connected between the pair of AC LEDs LD1 and LD11. The closed loop holding part 172 is connected between the pair of AC LEDs LD2 and LD22. The closed loop holding part 173 is connected between the pair of AC LEDs LD3 and LD33. The closed loop holding part 174 is connected between the pair of AC LEDs LD4 and LD44. The closed loop holding part 175 is connected between the pair of AC LEDs LD5 and LD55. The closed loop holding part 176 is connected between the pair of AC LEDs LD6 and LD66.

In FIG. 21, the number of pairs of alternating LEDs is represented as six, but the number can be added or subtracted, and the number of closed loop holding portions is also correspondingly added or reduced according to the number of pairs of alternating LEDs.

Hereinafter, a semiconductor switching element that may be employed in the closed circuit holder of FIG. 20 and the closed circuit holder of FIG. 21 will be described.

FIG. 22 is a diagram illustrating an example of a semiconductor switching element that can be employed in the closed circuit holding unit shown in FIG. 20. Since the internal configurations of the plurality of closed loop holders of FIG. 20 are the same, one closed circuit holder 161 will be described below as an example.

The closed-circuit holding unit 161 of FIG. 22 includes a Zener diode 1b which is turned on when a corresponding AC LED (eg, LD1) is opened and a voltage equal to or higher than a zener voltage is applied to the anode and cathode of the AC LED LD1, and Zener. As the diode 1b is turned on, it is provided with a silicon controlled rectifier (SCR) 1a for conducting a power supply path that bypasses the alternating LED LD1 to maintain a closed circuit. The control terminal (e.g., gate) of the silicon controlled rectifier 1a is connected to one end of the zener diode 1b. The silicon controlled rectifier 1a is a unidirectional element in which current always flows from anode to cathode. Here, the Zener diode 1b and the silicon controlled rectifier 1a may be regarded as an example of the semiconductor switching element described in the claims of the present invention.

When the closed-circuit holding part including the zener diode 1b and the silicon controlled rectifier 1a is connected to each LED one by one, the circuit diagram of FIG.

FIG. 24 is a diagram showing another example of the semiconductor switching element employable in the closed-circuit holding portion shown in FIG. 20. Since the internal configurations of the plurality of closed loop holders of FIG. 20 are the same, one closed circuit holder 161 will be described below as an example.

The closed-circuit holding unit 161 of FIG. 24 has a Zener diode 2b which is turned on when a corresponding AC LED (eg, LD1) is opened and a voltage equal to or higher than a zener voltage is applied to the anode and cathode of the AC LED LD1, and Zener. As the diode 2b is turned on, it is provided with a triac 2a that conducts and forms a power passage path bypassing the alternating LED LD1 to maintain a closed circuit. The control terminal (e.g., gate) of the triac 2a is connected to one end of the zener diode 2b. The triac 2a is a bidirectional element, but can be employed in a unidirectional circuit as shown in FIG. Here, the Zener diode 2b and the triac 2a may be regarded as an example of the semiconductor switching element described in the claims of the present invention.

Conventionally, only a zener diode for surge absorption is used to maintain a closed circuit. In this case, for example, when the AC LED LD1 is opened, an overvoltage greater than or equal to the zener voltage of the corresponding zener diode is applied to both ends of the zener diode. This causes the corresponding zener diode to be shorted due to overcurrent, so that even if the AC LED (LD1) is opened, it seems to maintain the closed circuit through the shorted zener diode. However, this is suitable for a short time, but after a certain time, the zener diode is opened by overcurrent. In particular, Zener diodes are very inefficient at high currents and are often burned out.

However, as shown in FIGS. 22 and 24, when the AC LED LD1 is opened and a voltage equal to or greater than the zener voltage is applied to the anode and the cathode, the silicon controlled rectifier SCR 1a is initially provided through the zener diodes 1b and 2b. Alternatively, the triac 2a is conducted, and then a voltage between the anode and the cathode flows through the silicon controlled rectifier (SCR) 1a or the triac 2a. Therefore, even if the closed-circuit holding unit 10 operates for a long time, the zener diodes 1b and 2b are not destroyed.

In other words, when the closed-circuit holding unit 161 is constituted as shown in FIGS. 22 and 24, not only the opening and breaking of the zener diodes 1b and 2b are generated, but also the silicon controlled rectifier 1a or the zener voltage. The operation and surge absorption capability of the triac 2a is superior to the circuit of the zener diode alone.

FIG. 25 is a diagram showing an example of a semiconductor switching element that can be employed in the closed circuit holding portion shown in FIG. 21. Since the internal configurations of the plurality of closed loop holders of FIG. 21 are the same, the following description will be given with reference to any one of the closed loop holders 171.

The closed circuit holding part 171 of FIG. 25 is formed of a silicon diode for alternating current (SIDAC) that is a semiconductor switching element. The closed-circuit holding unit 171 is energized when any one of the pair of corresponding AC LEDs LD1 and LD11 is opened and the voltage applied to the anode and the cathode of the corresponding AC LED is equal to or greater than the breakover voltage. Then, the closed circuit holding unit 171 forms a power passage path bypassing the open AC LED to maintain the closed circuit. Saidak is a bidirectional two-terminal thyristor, and has a structure similar to that of a shockley diode connected in anti-parallel.

When the closed circuit holding unit 171 is configured as a sid, it is not only possible to maintain the closed circuit by bypassing the alternating current LED when the alternating current LED is opened, and is also used to protect the surge voltage of the AC line by being strong against high voltage and high current.

FIG. 26 is a diagram showing another example of the semiconductor switching element employable in the closed-circuit holding portion shown in FIG. 21. Since the internal configurations of the plurality of closed loop holders of FIG. 21 are the same, the following description will be given with reference to any one of the closed loop holders 171.

The closed circuit holding unit 171 of FIG. 26 is turned on as one of the pair of AC LEDs LD1 and LD11 is opened and a voltage applied to the anode and the cathode of the AC LED is greater than or equal to the Zener voltage. As the first Zener diode 171b or the second Zener diode 171c and the first Zener diode 171b or the second Zener diode 171c are turned on, a power passage path is conducted to bypass the open AC LED. It is provided with a triac (Triac) 171a for maintaining a closed circuit.

The anode of the first zener diode 171b and the anode of the second zener diode 171c are connected to each other, and the node between the anode of the first zener diode 171b and the anode of the second zener diode 171c is a triac ( It is connected to the control terminal (gate) of 171a. The cathode of the first zener diode 171b and the second zener diode 171c is connected to different terminals of the triac 171a and is connected to the anode and cathode of the AC LED LD1 and the AC LED LD11. do.

In FIG. 26, for example, when the AC LED LD1 is opened while driving the AC LED LD1 and a voltage equal to or greater than the zener voltage is applied to the anode and the cathode, the triac 171a is initially transferred through the zener diode 171c. After that, the voltage between the anode and the cathode flows through the triac 171a. Therefore, even if the closed-circuit holding unit 171 operates for a long time, the corresponding zener diode 171c is not destroyed. The same applies to the case where the AC LED LD11 is opened while the Zener diode 171b is turned on while driving the AC LED LD11.

In other words, when the closed-circuit holding unit 171 as shown in FIG. 26 is configured in the bidirectional line, the opening and destruction of the zener diodes 171b and 171c are not generated, and as described above, the triac ( The operation and surge absorption capability of 171a is superior to that of the zener diode alone circuit.

(Example 9)

27 is a circuit diagram of the LED driving apparatus according to the ninth embodiment of the present invention. In more detail, it is a circuit diagram which shows the structure of the low voltage alternating current power converter.

The ninth embodiment includes a rectifier 182, an oscillator 184, and a transformer 186.

The rectifier 182 is connected to the input terminal 180 to which commercial AC power is input. The rectifier 182 full-wave rectifies the commercial AC power input from the input terminal 180. The rectifier 182 is configured of a bridge diode BD.

The oscillator 184 is installed between the rectifier 182 and the transformer 186. The oscillator 184 is installed between both ends of the output of the rectifier 182, one end of which is connected to one end of the primary side of the transformer 186 having a predetermined winding ratio together with one end of the output of the rectifier 182. ); And one end is connected to the time constant elements (R1, C1) and the other end is connected to the other end of the primary side of the transformer 186, switching driven by a pulse width modulation (PWM) signal from the outside to output the output of the transformer 186 And a switching unit (185, Q1) for outputting the oscillation signal for.

The switching units 185 and Q1 may include: a photo coupler 185 driven on / off in accordance with an input pulse width modulation (PWM) signal; And a first stage (eg, a collector) is connected to the other end of the primary side of the transformer 186, and a second stage (eg, an emitter) is connected to an output end of the rectifier 182 and a time constant element, and a control stage (eg, The base) is connected to the output terminal of the photo coupler 185, and includes a switching element Q1 that switches according to the on / off driving of the photo coupler 185. Since the photo coupler 185 uses light, the photo coupler 185 is resistant to noise and has a very fast response speed. The photo coupler 185 does not transmit an output signal to the input side because the light emitting part and the light receiving part are electrically insulated from each other and signal transmission is unidirectional. Due to the characteristics of the photo coupler 185, the switching operation of the switching element Q1 can be performed more reliably.

In FIG. 27, the switching element Q1 is used as a transistor, but may be a FET or an IGBT (Insulated Gate Bipolar Transistor).

The transformer 186 has a winding ratio and size that can generate, for example, a low voltage AC power of approximately 24 V or less based on a predetermined AC power applied to the primary side.

The operation of the ninth embodiment configured as described above will now be described.

The commercial AC power (for example, AC 220V) input to the input terminal 180 is full-wave rectified by the rectifier 182 and applied to the primary side of the oscillator 184 and the transformer 186.

Accordingly, the transformer 186 outputs a power source having a waveform shape almost similar to that of the power source applied to the primary side (full wave rectified power source) on the secondary side, but based on the oscillation signal from the oscillator 184, the frequency of one cycle The signal is separated into a plurality of detailed on / off signals and output.

That is, the photo coupler 185 of the oscillator 184 is turned on / off according to the pulse width modulation (PWM) signal input to the external control signal input terminal 190, and the photo coupler 185 is turned on / off by The switching element Q1 is turned on / off. Based on the on / off state of the switching element Q1, the voltage excited on the secondary side of the transformer 186 is output through the output terminal 188 as shown in FIG. Signal separated into a detailed on / off signal). Here, if the frequency and pulse width of the pulse width modulation (PWM) signal is adjusted, the output voltage (low voltage AC voltage) of the transformer 186 outputted through the output terminal 188 can be easily adjusted with a combination of small elements. do. Usually the size of transformer 186 is inversely proportional to frequency. If the frequency of the output voltage of the transformer 186 can be increased in the same circuit configuration, the desired circuit can be realized even by reducing the size of the transformer 186. Thus, the frequency and pulse width of the pulse width modulation (PWM) signal are adjusted. Is very useful.

In the ninth embodiment described above, there are not many circuit elements used to convert a commercial AC power source to a low voltage AC power source, so that the circuit can be implemented very simply and at low cost. In addition, the output of the transformer 186 may be easily controlled by the frequency and pulse width of the pulse width modulation (PWM) signal input to the external control signal input terminal 190.

In addition, when the AC LED (load) is connected to the secondary side of the transformer 186 or AC LED (load) instead of the transformer 186, the pulse width modulation (PWM) signal input to the external control signal input terminal 190 The dimming of the corresponding AC LED (load) is possible by means of the frequency and pulse width.

(Example 10)

28 is a circuit diagram of the LED driving apparatus according to the tenth embodiment of the present invention. In more detail, it is a circuit diagram which shows the structure of the low voltage alternating current power converter. 29 and 30 are waveform diagrams illustrating output signal waveforms of the circuit diagram of FIG. 28. The same components as those of the ninth embodiment described above among the components of the tenth embodiment are denoted by the same reference numerals, and description thereof will be omitted.

The tenth embodiment differs from the ninth embodiment described above in that the output of the transformer can be controlled by a variable resistor without receiving a pulse width modulation (PWM) signal from the outside.

The tenth embodiment includes a rectifier 182, an oscillator 192, and a transformer 186 as in the ninth embodiment described above.

The oscillator 192 is connected to one end of the output of the rectifier 182 and one end of the primary side of the transformer 186, and performs time constant control by the variable resistor VR to perform time constant elements R10, R11, R12, and VR. , C10, C11); And switching units Q10 and Q11 that are driven on / off according to variable time constants in the time constant elements R10, R11, R12, VR, C10, and C11 to output an oscillation signal for the output of the transformer 186. It includes. More specifically, one end of the resistors R10, R11, and R12 is connected between one end of the output of the rectifying unit 182 and one end of the primary side of the transformer 186. The capacitor C10 is connected between the resistor R10 and the resistor R11, and the connection node between the capacitor C10 and the resistor R11 is a control terminal (eg, a base) of the second switching element Q11 of the switching unit. Is connected to. The other end of the resistor R12 is connected to a control terminal (eg, a gate) of the first switching element Q10 of the switching unit through the variable resistor VR. The capacitor C11 is connected between the variable resistor VR and the other end of the primary side of the transformer 186. The first stage (eg, collector) of the first switching element Q10 is connected to the connection node of the resistor R10 and the capacitor C10, and the second stage (eg, emitter) of the first switching element Q10. Is connected to the other end of the output of the rectifier 182. The first end (eg, collector) of the second switching element Q11 is connected to the connection node between the other end of the primary side of the transformer 186 and the condenser C11, and the second end (eg, of the second switching element Q11). Emitter) is connected to the other end of the rectifying unit 182 together with the second end of the first switching element Q10.

In Fig. 28, the first and second switching elements Q10 and Q11 are transistors, but they may be FETs or Insulated Gate Bipolar Transistors (IGBTs).

The operation of the tenth embodiment configured as described above will be described below.

The commercial AC power (for example, AC 220V) input to the input terminal 180 is full-wave rectified by the rectifying unit 182 and applied to the primary side of the oscillator 192 and the transformer 186.

As a result, the transformer 186 outputs the power excited by the power source (the full wave rectified power source) applied to the primary side on the secondary side, based on the oscillation signal from the oscillation unit 192.

That is, the oscillation signal according to the time constant determined by the resistance value adjustment of the variable resistor VR is provided to the transformer 186. Accordingly, when the resistance of the variable resistor VR is minimized, a voltage having the waveform as shown in FIG. 29A is generated at the point A of the primary side of the transformer 186, and 2 of the transformer 186 is generated. A voltage (low voltage AC voltage) having a waveform as shown in FIG. 29B is output to the output terminal 188 through the vehicle side. On the contrary, when the resistance value of the variable resistor VR is maximized, the voltage having the waveform as shown in FIG. 30A is generated at the point A of the primary side of the transformer 186, and the secondary side of the transformer 186 is generated. The output terminal 188 outputs a voltage (low voltage AC voltage) having a waveform as shown in FIG. In this case, when the variable resistor VR is adjusted, the output voltage of the transformer 186 outputted through the output terminal 188 may be easily adjusted by a combination of less elements. Usually the size of transformer 186 is inversely proportional to frequency. If the frequency of the output voltage of the transformer 186 can be increased in the same circuit configuration, since the desired circuit can be implemented even by reducing the size of the transformer 186, the variable resistor VR is very useful.

In the case of the tenth embodiment described above, there are not many circuit elements used to convert a commercial AC power source to a low voltage AC power source, so that the circuit can be implemented very simply and the circuit can be implemented at a low price. The output of the transformer 186 can be easily controlled by the variable resistor VR.

In addition, when the AC LED (load) is connected to the secondary side of the transformer 186 or the AC LED (load) instead of the transformer 186, dimming (dimming) for the corresponding AC LED (load) with a variable resistor (VR) Is possible.

In the ninth and tenth embodiments of the present invention described above, LED dimming is possible at AC low pressure and high pressure, and RGB control is also possible. There are few component elements for circuit realization, which improves reliability and can be applied to AC-AC converters. In particular, since it has a higher efficiency than the DC circuit using SMPS, it is possible to secure a great competitive advantage in the AC LED market, especially low voltage.

On the other hand, the present invention is not limited only to the above-described embodiment, but can be modified and modified within the scope not departing from the gist of the present invention, and the technical spirit to which such modifications and variations are applied also belong to the following claims Must see

Claims (28)

1. An LED module arrayed in a metal PC is connected to a plurality of commercial power input lines.

   And a blocking device installed on all input lines of the LED module connected to the plurality of commercial power input lines, respectively, to block the commercial power input to all the input lines of the LED module. .
2. The method according to claim 1,

   The blocking device is an LED driving device, characterized in that composed of a semiconductor switching element or an AC relay provided with a switch on each of all the input lines of the LED module.
3. The method according to claim 1,

   LED driving device further comprises a bridge diode at the rear end of the blocking element.
4. The method according to claim 1,

   The LED driving device, characterized in that it further comprises a filter for blocking the noise flowing into the input line of the LED module to the input line of the LED module.
5. Rectifier for rectifying commercial power from the power stage;

   A first switching driver and a second switching driver driven on / off based on the output signal of the rectifier and including a photo triac;

   A first semiconductor switching element installed between the first switching driver and one end of the load and forming a power supply path between the power supply terminal and one end of the load as the first switching driver is turned on; And

   And a second semiconductor switching element installed between the second switching driver and the other end of the load and forming a power supply path between the power supply terminal and the other end of the load as the second switching driver is turned on. LED drive.
6. The method according to claim 5,

   And a time constant part for controlling phases of the first and second semiconductor switching elements.
7. The method according to claim 6,

   The time constant unit is installed between the power supply stage and the rectifier, LED drive device characterized in that it comprises a variable resistor and a capacitor.
8. A first switching driver and a second switching driver driven on / off based on the input signal and including a photo triac;

   A first semiconductor switching element installed between a power supply terminal and one end of a load and forming a power supply path between the power supply terminal and one end of the load as the first switching driver is turned on;

   A second semiconductor switching element installed between the power supply terminal and the other end of the load and forming a power supply path between the power supply terminal and the other end of the load as the second switching driver is turned on;

   A phase sensing unit sensing a phase of an input external signal and outputting an AC signal corresponding thereto; And

   And a rectifier for rectifying the AC signal from the phase sensing unit and sending the rectified AC signal to the first switching driver and the second switching driver.
9. The method according to claim 8,

   The LED driving device, characterized in that the external signal input to the phase sensing unit is input in the form of a PWM wave or a square wave.
10. Rectifier for rectifying commercial power from the power stage;

    A switching driver driven on / off based on the output signal of the rectifier and including a photo triac;

    A semiconductor switching element disposed between the power supply terminal and one end of the load and forming a power supply path from the power supply terminal to the load as the switching driver is turned on; And

    And a selection switch unit disposed between the power supply terminal and both ends of the load, and configured to turn off the switching driving unit by an operation to block a power supply path from the power supply terminal to the load.
11. The method according to claim 10,

    And the semiconductor switching device comprises a triac.
12. As a device for driving the LED,

    A switching unit including a rectifier including a semiconductor switching element turned on / off according to an input control signal, and rectifying an input AC commercial power and outputting the rectified AC power to the LED; And

    And a control unit for generating a control signal for turning on / off the semiconductor switching element and outputting the control signal to the switching unit.
13. The method according to claim 12,

    And the semiconductor switching device comprises a thyristor or a triac.
14. The method according to claim 12,

    An LED driving device is connected between the switching unit and the AC commercial power input terminal, characterized in that further comprising a transformer for sending a voltage drop to the AC commercial power input to the switching unit.
15. The method according to claim 14,

    The switching unit may include a first switching unit connected to the first secondary side of the transformer unit; And second and third switching parts connected to the second secondary side of the transformer part.

    The number of coil windings on the first secondary side of the transformer unit is smaller than the number of coil turns on the second secondary side of the transformer unit.
16. A device having a one-way power passage path in which a plurality of AC LEDs receiving AC commercial power are connected in series with each other.

    A plurality of closed-circuit holding portions connected one to one to each of the plurality of alternating current LEDs,

    Each of the plurality of closed-circuit holders is connected to a first semiconductor switching device that is turned on when a corresponding AC LED is opened and a voltage applied to both ends is greater than or equal to a predetermined value. And a second semiconductor switching element to be formed.
17. The method according to claim 16,

    And the first semiconductor switching element is composed of a zener diode.
18. The method according to claim 17,

    And said second semiconductor switching element comprises a silicon controlled rectifier (SCR) or a triac with a control end connected to one end of said zener diode.
19. As a device having a bi-directional power passage path by arraying a plurality of AC LEDs receiving an AC commercial power,

    A plurality of closed-circuit holding portions connected one to one to each of the pair of alternating LEDs,

    Each of the plurality of closed-circuit holding portions is a semiconductor switching element that is electrically connected as one of the corresponding pair of AC LEDs is opened and the voltage applied to both ends thereof is greater than or equal to a predetermined value, thereby forming a power passage path. LED drive.
20. The method according to claim 19,

    LED driving device, characterized in that the semiconductor switching element is composed of a side.
21. The method according to claim 19,

    The semiconductor switching device may include a first semiconductor switching device that is turned on when an AC LED of a corresponding pair of AC LEDs is opened and a voltage applied to both ends thereof is greater than or equal to a predetermined value, and as the first semiconductor switching device is turned on. And a second semiconductor switching element that is electrically connected to form a power passage path.
22. The method according to claim 21,

    And said first semiconductor switching element comprises a first zener diode and a second zener diode connected between a corresponding pair of alternating LEDs.
23. The method according to claim 22,

    And said second semiconductor switching element comprises a triac with a control terminal connected between said first and second zener diodes.
24. A device for converting commercial AC power into low-voltage AC power and outputting

    A time constant element installed between both ends of the rectifier for rectifying the commercial AC power source, one end of which is connected to one end of a primary side of a transformer having a predetermined turns ratio together with an output end of the rectifier; And

    One end is connected to the time constant element, the other end is connected to the other end of the primary side of the transformer having a predetermined turns ratio, and is switched by a PWM signal from the outside to output an oscillation signal for outputting a low voltage AC power of the transformer. LED drive device comprising a switching unit.
25. The method of claim 24,

    The switching unit,

    A photo coupler driven on / off according to the input PWM signal; And

    And a switching device for switching according to the on / off driving of the photo coupler.
26. A device for converting commercial AC power into low-voltage AC power and outputting

    A time constant element connected to an output end of the rectifying unit for rectifying the commercial AC power source and a primary side of a transformer having a predetermined winding ratio, and performing variable time constant control; And

    And a switching unit which is driven on / off according to a variable time constant in the time constant element and outputs an oscillation signal for outputting an AC power at a low voltage of the transformer.
27. The method of claim 26,

    And the time constant element includes a variable resistor and is connected between an output end of the rectifying unit and a primary side of the transformer.
28. The method of claim 27,

    The switching unit is provided between the output end of the time constant element and the rectifier and the primary side of the transformer, the control stage comprises a first switching element and a second switching element connected to the time constant element, respectively LED drive.

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