JP2012221595A - Led turn-on device, reverse phase control device and lighting control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device which would not cause errors in voltage polarity for an LED connected to an LED turn-on device.SOLUTION: An LED turn-on device 3 comprises a full-wave rectifier circuit 31 which is disposed at an input end to which a full-wave rectified voltage is fed into from a reverse phase control device which, in each cycle of a voltage derived from an AC voltage by full-wave rectification, outputs the full-wave rectified voltage for only a certain period from substantially the beginning of each of the cycles and a capacitor 32 which is connected at one end to a cathode of the full-wave rectifier circuit 31 and connected at the other end to an anode of the full-wave rectifier circuit 31.

Description

  The present invention relates to an LED lighting device, an antiphase control device, and a dimming system.

2. Description of the Related Art There is known an apparatus for dimming an illumination load by controlling the phase of an AC power source using a semiconductor element such as a thyristor. In this type of apparatus, a steep voltage is applied to the illumination load when the semiconductor element is conducted in the vicinity of an electrical angle of 90 degrees. For this reason, there is a case where noise is generated, and there is a technique relating to an antiphase control device as an improvement (see, for example, Patent Document 1). In FIG. 1 of Patent Document 1, an antiphase control device 2 includes a rectifier 11 that performs full-wave rectification of an AC power supply voltage V1, an FET 12 that is interposed between the illumination load 2, and a zero-cross of the voltage that has been subjected to full-wave rectification. A zero cross detection unit 13 for detecting, a dimming level setting unit 14 for setting the dimming level of the illumination load 2, and a control unit 15 for turning on the FET 12 at the zero cross timing and turning off at a predetermined firing angle. The illumination load 2 is connected to the load connection unit 16. Due to the connection of the rectifier 11, a voltage only in the positive direction is supplied to the illumination load 2. Moreover, the following (a)-(e) is shown by FIG. 2 of patent document.
(A) AC power supply voltage,
(B) full-wave rectified voltage,
(C) a zero-cross signal generated by the zero-cross detector 13;
(D) PWM signal output from the control unit 15 (FET12 is on when high),
(E) Supply voltage to the lighting load (positive voltage).
In the device of Patent Document 1, the lighting load 2 is dimmed and controlled by changing the ON period of the PWM signal (e). Thus, there has been an apparatus that reduces the number of parts by using FETs in the antiphase control apparatus.

JP 2010-27406 A (see FIGS. 1 and 2)

  However, when an LED lighting device including a converter is used as a load of the antiphase control device, it is difficult to establish a stable operation of the converter unless an appropriate antiphase control voltage is supplied. Moreover, if the polarity of the voltage polarity of the LED lighting device that receives the reverse phase control voltage is reversed, there is a problem that the LED lighting device is broken.

  An object of the present invention is to provide an apparatus that stabilizes the operation of an LED lighting device by appropriately setting a period for supplying an antiphase control voltage and that does not cause an error in voltage polarity in connection of the LED lighting device. .

The LED lighting device of the present invention is
In each cycle of the voltage in which the AC voltage is full-wave rectified, the full-wave rectified voltage is output from the anti-phase control device that outputs the full-wave rectified voltage for a certain period from the substantially start of each cycle. A full-wave rectifier circuit that is arranged at an input terminal for inputting the full-wave rectified voltage, and
And a capacitor having one end connected to the positive electrode of the full-wave rectifier circuit and the other end connected to the negative electrode of the full-wave rectifier circuit.

  According to the LED lighting device of the present invention, since the full-wave rectifier circuit and the capacitor are provided on the input end side, the connection polarity of the LED can be made nonpolar.

1 is a circuit diagram of a light control system 100 according to Embodiment 1. FIG. FIG. 3 is a circuit diagram of the LED lighting device 3 according to the first embodiment. FIG. 6 is another circuit diagram of the LED lighting device 3 according to the first embodiment. FIG. 4 is a diagram for explaining the operation of the antiphase control device 2 according to the first embodiment. FIG. 6 illustrates an operation of the conduction control circuit 24 according to the first embodiment. FIG. 6 illustrates the operation of the switching control circuit according to the first embodiment. The figure which shows the soft start operation | movement and steady operation of Embodiment 1 by the relationship with the phase of AC power supply. FIG. 6 illustrates a minimum on-period Ton in the first embodiment.

Embodiment 1 FIG.
FIG. 1 is a circuit diagram of a dimming system 100 according to the first embodiment.
2 and 3 show examples of the respective LED lighting devices 3 applicable to the first embodiment.
FIG. 4 is a voltage waveform for explaining the principle operation of the antiphase control device 2 of the first embodiment. FIG. 4 is a diagram for supplying a voltage to the LED lighting device 3 serving as a load during the period from the phase θ0 of the zero crossing position of the AC power supply voltage to the desired phase θ1. The reverse phase control device 2 stops power feeding from the AC power supply side to the load at the phase θ1 and adjusts the load by appropriately changing the phase θ1.

In FIG. 1, the dimming system 100 includes:
(1) An AC power source 1 is input and an anti-phase control device 2 that controls the phase of the AC power source 1;
(2) It comprises a plurality of LED lighting devices 3 connected in parallel to the antiphase control device 2.

The anti-phase control device 2 is
(1) a rectifier circuit 21 for full-wave rectifying the alternating current of the alternating current power supply 1,
(2) a transistor 22 connected to the rectifier circuit 21 and turned on while the on-period signal is output from the conduction control circuit 24 (herein, an element referred to as a MOS-FET);
(3) a capacitor 23 connected in parallel between the collector and emitter of the transistor 22;
(4) a conduction control circuit 24 that generates an on-period signal (on signal) of the transistor 22 and outputs the signal to the transistor 22, and turns on the transistor 22 during the output of the on-period signal;
(5) Input a voltage (FIG. 5 (2) described later) output for a certain period from the beginning of each period of the full-wave rectified voltage based on the ON period signal output from the conduction control circuit 24, and turn on the LED. The connection part 20a, 20b with which the positive electrode and negative electrode of the LED lighting device 3 to be connected are connected is provided. The conduction control circuit 24 is connected so that an on-period signal of the transistor 22 can be generated without going through the LED lighting device 3 as a load. That is, the continuity control circuit 24 does not depend on whether the LED lighting device 3 is connected to the connection portions 20a and 20b, and the on-period signal is based on the waveform of the voltage that is full-wave rectified by the rectifier circuit 21 as described later. Is generated.

  The LED lighting device 3 lights a light emitting diode (hereinafter referred to as LED 4). The LED lighting device 3 supplies the DC power (current) to the LED 4 with the power supplied from the antiphase control device 2 to light it.

  FIG. 5 is a diagram illustrating the operation of the conduction control circuit 24. The horizontal axis is time (or phase), and the vertical axis is each value of (1) to (4). As shown in FIG. 5, the conduction control circuit 24 of the reverse phase control device 2 uses the power supply synchronization signal (3) generated from the rectified voltage (2) obtained by rectifying the voltage (1) of the AC power supply, thereby turning on the period. Signal (4) is generated. Thereby, the transistor 22 supplies a voltage to the LED lighting device 3 during the period from the phase θ0 to the phase θ1.

Here, it is assumed that the LED lighting device 3 is configured as shown in FIG. In FIG. 2, the LED lighting device 3 includes a full-wave rectifier circuit 31, a capacitor 32 connected to the output terminal of the full-wave rectifier circuit 31, a switching element 33, and a switching control circuit that controls switching of the switching element 33. 34 (lighting control unit). The capacitor 32 has one end connected to the positive electrode of the full wave rectifier circuit 31 and the other end connected to the negative electrode of the full wave rectifier circuit 31.
(1) The capacitor 32 is often a relatively small-capacitance capacitor corresponding to dimming in phase control.
(2) The switching element 33 is a switching element of the LED lighting device 3 of FIG. 2 that is called a flyback converter that generates DC power for lighting the LED 4, and is switched at a high frequency, so that its secondary side A direct current is generated in the capacitor 35 and the LED 4 is turned on.
(3) The switching control circuit 34 controls switching of the switching element 33. The switching control circuit 34 controls the power (current) of the LED 4 by changing, for example, a high-frequency pulse width.
FIG. 6 is a diagram for explaining the operation of the switching control circuit 34. FIG. 6A shows the relationship between the soft start time and the steady operation time, and FIG. 6B shows the pulse output from the switching control circuit 34. In FIG. 6, the supply of the AC power supply 1 is started at t0, the control voltage of the switching control circuit 34 rises at t1, and the switching control circuit 34 starts operation. In the soft start period (t1 to t2) at the initial stage of operation, the switching control circuit 34 narrows the pulse width for driving the switching element 33 on as shown in FIG. 6B, and then gradually widens the pulse width. Moves to the set steady operation. This is to stably supply power to the LED 4.

  FIG. 7 is a diagram showing the soft start operation and the steady operation in relation to the phase of the AC power supply 1. FIG. 7A shows the AC power supply voltage, and FIG. 7B shows the relationship between the soft start time and the steady operation time. Here, the period of θ0 to θs is a generation period of the synchronization signal. In the on-phase period Ton (corresponding to θ0 to θ1), the reverse phase control device 2 needs a minimum period until the LED lighting device 3 passes the soft start period and enters the steady operation period. If the anti-phase control device 2 is turned off during the soft start period (θs to t2) and power supply is stopped, the LED does not reach a predetermined lighting state and is likely to be in an unstable lighting state.

  The first embodiment also proposes a minimum supply period Ton (a period of θ0 to θ1) as a lower limit for this stable operation. The LED lighting device 3 has a direct current conversion function for supplying a predetermined direct current to the LED 4. However, at the time of soft start (θs to t2 in FIG. 7), it takes about 0.5 to 1.0 ms for steady operation. Further, it takes about 0.25 ms for the generation period (θ0 to θs) of the synchronization signal of the AC power supply 1. These are requirements when trying to operate reliably with current technology. If it is desirable that the instantaneous value supplied from the anti-phase control device 2 reaches about 40% or more in the case of a 100V power supply, a preferable state is set as follows.

In the first embodiment, the ON period Ton (θ0 to θ1) is set to 27 degrees or more in electrical angle. That is, the conduction control circuit 24 generates an on period signal (FIG. 5 (4)) so that the on period Ton becomes 27 electrical degrees or more. As a result, the power supply period is about 1.3 ms in the 50 Hz region and about 1 ms in the 60 Hz region. This will be described with reference to FIG.
FIG. 8 is a table for explaining the minimum on-period Ton. As shown in FIG. 8, the on period Ton was set to an electrical angle of 27 degrees. In this case, if the power supply period is 50 Hz,
(1/50) × (27/360) = 1.50 ms
Similarly, it is 1.25 ms in the 60 Hz region. As described above, if the period for generating the synchronization signal requires about 0.25 ms from the phase θ 0, the substantial energization time subtracts 0.25 ms,
50Hz region → 1.25ms ≒ 1.3ms,
60Hz area → 1.0ms,
It becomes. As shown in FIG. 8, the instantaneous value at this time can secure a sufficient voltage of 64 Vo-p with respect to the power supply 100V (effective value). By setting in this way, the LED lighting device 3 can be steadily operated within each half cycle of the AC power supply and the LED lighting device 3 can also dimm the LED deeply without any trouble such as stoppage due to low voltage. I can do it.

  In the dimming system 100 of FIG. 1, a surge voltage is often applied due to the impedance of the wiring of the AC power supply 1 at the moment when the AC power supply 1 is turned on by a power supply side switch (not shown). . In such a case, as shown in FIGS. 2 and 3, if the LED lighting device 3 includes a capacitor 32 on the input side, the voltage stress on the LED lighting device 3 is reduced even if the voltage value of the surge voltage is reduced. Can be reduced. Further, the capacitor 23 connected in parallel with the transistor 22 (FIG. 1) of the antiphase control device 2 is useful for reducing the surge voltage. In thyristor elements, even if a surge voltage is applied and breaks over and turns on, the element will not be destroyed immediately. It must be avoided because it often causes damage. Therefore, the connection of the capacitor 23 is very effective when there is no margin with respect to the surge voltage to which the breakdown voltage of the transistor 22 is applied. Further, even if a resistance is connected to the transistor 22 in parallel, the effect can be further enhanced.

  In a normal phase control device, when the capacitor 32 is provided on the input side of the LED lighting device, a steep voltage subjected to phase control is applied to the LED lighting device 3 every half cycle of the AC power supply. For this reason, a large inrush current may flow or unpleasant noise may occur. However, since the output voltage of the antiphase control device 2 of the first embodiment does not apply this steep voltage to the LED lighting device 3 due to the effect of the capacitor 23 and the capacitor 32, these problems do not occur.

  The transistor 22 of the antiphase control device 2 is composed of a type of transistor called a MOS FET in the drawing. However, other elements such as bipolar transistors and transistors called IGBTs can also be used.

  The conduction control circuit 24 can generate a signal without being influenced by the number of connected LED lighting devices 3 by generating a signal without passing through the LED lighting device 3 as a load. In addition, when the LED lighting devices 3 can be individually opened and closed by a switch (not shown), the transistor is also used when all the LED lighting devices 3 are in the OFF state or during the inspection operation in which the LED lighting devices 3 are not attached. There is an advantage that 22 on-period signals can be generated.

  Although the output of the reverse phase control device 2 has positive and negative polarities, the LED lighting device 3 includes the full-wave rectifier circuit 31 at the input end thereof, which causes a problem in the polarity of the connection with the LED lighting device 3 at the time of construction. Disappears. The basic configuration of a normal LED lighting device 3 that turns on an LED from the AC power supply 1 includes a full-wave rectifier circuit on the input side, and therefore the anti-phase control device 2 of the first embodiment using the same printed circuit board. There is a convenience that can be applied to.

  According to the dimming system 100 described above, it is possible to set a minimum electrical angle for supplying an antiphase control voltage during dimming, and to ensure stable operation of the LED lighting device 3 until deep dimming. Further, by providing a full-wave rectifier on the input end side of the LED lighting device 3, it is possible to eliminate erroneous connection in construction.

  DESCRIPTION OF SYMBOLS 1 AC power supply, 2 Reverse phase control apparatus, 3 LED lighting apparatus, 4 LED, 20a, 20b Connection part, 21 Rectifier circuit, 22 Transistor, 23 capacitor | condenser, 24 Continuity control circuit, 31 Full wave rectifier circuit, 32 Capacitor, 33 Switching Element, 34 switching control circuit, 35 capacitor, 38 diode, 100 dimming system.

Claims (5)

In each cycle of the voltage in which the AC voltage is full-wave rectified, the full-wave rectified voltage is output from the anti-phase control device that outputs the full-wave rectified voltage for a certain period from the substantially start of each cycle. A full-wave rectifier circuit that is arranged at an input terminal for inputting the full-wave rectified voltage, and
An LED lighting device comprising: a capacitor having one end connected to the positive electrode of the full-wave rectifier circuit and the other end connected to the negative electrode of the full-wave rectifier circuit. The LED lighting device further includes:
2. The lighting control unit for executing a soft start for gradually increasing the light output of the LED based on the voltage of each period input from the anti-phase control device to the full-wave rectifier circuit. LED lighting device. A rectifier circuit for full-wave rectification of AC voltage;
A transistor that is arranged in the middle of a path of a current that flows from the positive electrode to the negative electrode of the rectifier circuit, and that turns on and off the conduction of the current that flows through the path according to an input control signal;
A conduction control circuit that generates an on signal that commands the transistor to turn on the conduction only for a certain period from the substantially start of each cycle of the voltage that has been full-wave rectified by the rectifier circuit, and outputs the generated on signal to the transistor When,
A connecting portion to which a positive electrode and a negative electrode of an LED lighting device for lighting a LED by inputting a voltage output for a certain period from a substantially start time of each cycle based on the ON signal output by the conduction control circuit is connected. Prepared,
The conduction control circuit is:
Regardless of whether the LED lighting device is connected to the connection portion, the on-phase signal is generated based on the waveform of the voltage that is full-wave rectified by the rectifier circuit. The conduction control circuit is:
The constant of the LED lighting device is dimmed by changing the length of the predetermined period instructed by the ON signal, and the constant is changed when the nominal rated voltage of the AC power supply that supplies the AC voltage is 100V. 4. The antiphase control device according to claim 3, wherein the length of the period is converted to an electrical angle of the AC voltage to be 27 degrees or more.   A dimming system comprising the LED lighting device according to claim 1 and the antiphase control device according to claim 3.

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