TW201444405A - Lighting device and symmetric dimming module thereof - Google Patents

Abstract

A symmetric dimming module divides an alternating-current voltage to a first cross voltage applied to a lighting load and a second cross voltage applied to a symmetric dimming module. The symmetric dimming module comprises a bridge circuit and a dimmer. The bridge circuit performs rectification of the second cross voltage for acquiring a positive phase rectified voltage. The dimmer receives the rectified voltage and uses the rectified voltage to generate a rectified current with magnitude related to the rectified voltage. The dimmer includes a time delay unit and a switch unit. The time delay unit carries out conversion in accordance with the rectified current and a time delay value for generating a switch voltage. The switch unit determines whether the conduction between a first and a second terminal is on in accordance with whether the switch voltage is greater than a default conduction value or not.

Description

Lighting device and its symmetrical dimming module

The invention relates to a device and a module thereof, in particular to an illumination device capable of adjusting the brightness of the illumination and a symmetric dimming module thereof.

Referring to FIG. 1 , a conventional phase-cut tuned dimming device 1 is connected in series with an alternating current source 6 and an illuminating load 7 that provide an alternating voltage V _AC , and the alternating voltage V _{AC is} divided into a voltage applied to the illuminating load 7 . a first voltage across the second voltage across the symmetrical dimming module 1 and the phase-cut tuned dimming device 1 for changing the first voltage across the illuminating load 7 The phase angle is turned on, and the output power of the light-emitting load 7 is changed by changing the conduction phase angle of the second voltage, that is, the light output of the light-emitting load 7 is changed.

The phase-cut type control dimming device 1 comprises a variable resistor 11, a fixed resistor 12, a capacitor 13, a bidirectional trigger diode (DIAC) 14, and a three-terminal three-phase controllable diode (TRIAC). 15.

Referring to FIG 2, when the alternating voltage V _AC for the positive half cycle and an amplitude increasing from zero, the cut-phase silicon controlled dimming mode of operation of apparatus 1 is: an AC current to be alternating i _AC voltage V _AC is by The variable resistor 11 and the fixed resistor 12 charge the capacitor 13 , and the AC voltage V _AC at this time is applied to the variable resistor 11 , the fixed resistor 12 , the capacitor 13 , and the illuminating load 7 , and The first cross-over voltage to which the illuminating load 7 is divided is small, so the illuminating load 7 hardly emits light. In further detail, when a resistance value of the variable resistor 11 becomes larger, the alternating current i _AC flowing through the capacitor 13 becomes smaller, so that the potential of the capacitor 13 is slower to reach the bidirectional triggering dipole. The trigger voltage of the body 14 and the three-terminal three-phase controllable diode 15 are also delayed to be turned on. Therefore, adjusting the resistance of the variable resistor 11 can adjust the three-terminal three-phase controllable diode 15 to be turned on. The time, that is, the conduction phase angle of the first voltage across. When the voltage across the capacitor 13 reaches a trigger voltage of the bidirectional trigger diode 14, the bidirectional trigger diode 14 is turned on (the potential of the terminal 141 is higher than the potential of the terminal 142).

Referring to FIG. 3, following the action of FIG. 2, after the bidirectional trigger diode 14 is turned on, the three-terminal three-phase controllable diode 15 is further triggered to be turned on, and the AC voltage V _{AC is} applied to the three ends of the conduction. The three-phase controllable diode 15 and the illuminating load 7 are discharged, and at this time, the capacitor 13 is discharged. In addition, the first voltage across the illuminating load 7 as shown in FIG. 3 is greater than that shown in FIG. The first voltage across the light-emitting load 7 is divided, and the light-emitting load 7 as shown in FIG. 3 emits light by using the first voltage.

Referring to FIG. 4, following the operation of FIG. 3, when the AC voltage V _AC is a negative half cycle and the amplitude is gradually increased from zero, the operation mode of the phase-cut type control dimming device 1 is similar to FIG. 2, and the light is emitted at this time. The first voltage across the load 7 is small and therefore hardly emits light, and at this time, the alternating current i _AC charges the capacitor 13 , and when the voltage across the capacitor 13 reaches the trigger of the bidirectional trigger diode 14 After the voltage, the bidirectional trigger diode 14 is turned on (the potential of the terminal 142 is higher than the potential of the terminal 141).

Referring to FIG. 5, following the action of FIG. 4, after the bidirectional trigger diode 14 is turned on, the three-terminal three-phase controllable diode 15 is further triggered to be turned on, and the AC voltage V _{AC is} applied to the three ends of the conduction. The three-phase controllable diode 15 and the illuminating load 7 are discharged, and at this time, the capacitor 13 is discharged. In addition, the first voltage across the illuminating load 7 as shown in FIG. 5 is greater than that shown in FIG. The first crossover voltage to which the illuminating load 7 is divided.

Referring to FIG. 6, the waveform of the first voltage across the light-emitting load 7 is obtained. The three-terminal three-phase controllable diode 15 is not turned on in each time interval Δt1, so the first cross-voltage is small and substantial. The ground is close to zero. In contrast, the three-terminal three-phase controllable diode 15 is turned on in each time interval Δt2, and the first voltage is changed following the AC voltage V _AC .

However, the phase-cut type 调 control dimming device 1 has the following disadvantages: due to the bidirectional triggering on-voltage between the two ends 141, 142 of the bidirectional trigger diode 14 (end point 141 minus the voltage of the terminal 142, and The voltage of the terminal 142 minus the terminal 141 is generally not consistent. Therefore, the waveform of the first voltage across the first half of the cycle will cause asymmetry of the positive and negative half-cycle conduction phase angles, thereby causing the illumination load 7 to be Produces flicker.

Accordingly, it is an object of the present invention to provide a symmetrical dimming module that can improve the asymmetry of positive and negative half cycle conduction phase angle asymmetry.

Therefore, the symmetric dimming module of the present invention is adapted to be connected in series with an alternating current power supply and an illuminating load for providing an alternating voltage, and the alternating voltage from the alternating current power source is divided into a first voltage across the illuminating load. And a second voltage across the symmetrical dimming module.

The symmetrical dimming module comprises a bridge circuit and a dimmer.

The bridge circuit includes a first and second common contacts for receiving the second voltage across, and a third and fourth common contacts, and the bridge circuit rectifies the second voltage across the ground A rectified voltage having a positive phase and outputting the rectified voltage from the third and fourth common contacts.

The dimmer is electrically connected between the third and fourth common contacts of the bridge circuit to receive the rectified voltage, and uses the rectified voltage to generate a rectified current of a magnitude related to the rectified voltage, and the rectified current is constant Flowing from the dimmer to the fourth common contact from the third common contact.

The dimmer includes a time delay unit and a switch unit.

The time delay unit performs conversion based on the rectified current and a time delay value to generate a switching voltage.

The switch unit has a first and a second end electrically connected to the third and fourth common contacts, and a control end electrically connected to the time delay unit to receive the switch voltage, and the switch unit is Whether the switch voltage is greater than a predetermined turn-on value determines whether the first and second ends of the switch unit are turned on.

Yet another object of the invention is to provide a lighting device.

The illumination device comprises the aforementioned symmetrical dimming mode and a illuminating load.

The illuminating load and the AC power source and the symmetrical dimming module Connecting in series, the AC voltage from the AC power source is divided into a first voltage across the light-emitting load, and a second voltage applied to the symmetric dimming module, and the first voltage-crossing drive The illuminating load emits light.

1‧‧‧ phase-cut type control dimming device

11‧‧‧Variable resistor

12‧‧‧Fixed resistance

13‧‧‧ Capacitance

14‧‧‧Two-way trigger diode

141‧‧‧Endpoint

142‧‧‧Endpoint

15‧‧‧Three-terminal three-phase controllable diode

2‧‧‧Bridge Circuit

21‧‧‧First rectifier

22‧‧‧Second rectifier

23‧‧‧ Third rectifier

24‧‧‧fourth rectifier

N1‧‧‧ first common joint

N2‧‧‧ second common joint

N3‧‧‧ third common joint

N4‧‧‧ fourth common joint

N5‧‧‧ fifth common joint

3‧‧‧Dimmer

31‧‧‧Time delay unit

311‧‧‧Variable resistor

312‧‧‧ Fixed resistor

313‧‧‧ Capacitance

314‧‧‧discharge element

32‧‧‧Switch unit

321‧‧‧Switching elements

322‧‧‧ Trigger components

4‧‧‧Inductance

5‧‧‧ damping circuit

51‧‧‧resistance

52‧‧‧ Capacitance

6‧‧‧AC power supply

7‧‧‧Lighting load

10‧‧‧Symmetric dimming module

20‧‧‧Lighting load

30‧‧‧AC power supply

△t1‧‧‧ time interval

△t2‧‧‧ time interval

T0~t4‧‧‧Time

V _AC ‧‧‧AC voltage

i _AC ‧‧‧AC current

I _AC ‧‧‧Rectified current

Other features and effects of the present invention will be apparent from the following description of the drawings. FIG. 1 is a circuit diagram illustrating a conventional phase-controlled dimming device; FIG. 2 to FIG. Is a schematic diagram of the path and flow direction of an alternating current of the phase-cut type control dimming device; FIG. 6 is a first voltage-crossing waveform diagram of a light-emitting load combined with the phase-cut type control dimming device; A circuit diagram illustrating a triggering component of a first preferred embodiment of the illumination device of the present invention is a Schaucle diode; FIG. 8 is a waveform diagram of the first preferred embodiment; FIG. 9 to FIG. FIG. 13 is a circuit diagram showing a trigger component of a second preferred embodiment of the illumination device of the present invention as a bidirectional trigger diode; FIG. 14 is a schematic diagram of the path and flow direction of the alternating current according to the first preferred embodiment; A circuit diagram illustrating a third preferred embodiment of the illumination device of the present invention; and Figure 15 is a circuit diagram illustrating a fourth preferred embodiment of the illumination device of the present invention.

Before the present invention is described in detail, it should be noted that in the following description, similar elements are denoted by the same reference numerals.

Referring to FIG. 7, a first preferred embodiment of the illumination device of the present invention includes a symmetric dimming module 10 and an illumination load 20.

The symmetrical dimming module 10 is connected in series with an AC power source 30 that supplies an AC voltage V _AC and the illuminating load 20, and the AC voltage V _AC from the AC power source 30 is divided into a voltage applied to the illuminating load 20 A crossover pressure and a second crossover pressure applied to the symmetrical dimming module 10.

The symmetrical dimming module 10 includes a bridge circuit 2 and a dimmer 3 .

The bridge circuit 2 includes a first and second common contacts N1, N2 for receiving the second voltage across, and a third and fourth common contacts N3, N4, and the bridge circuit 2 The second voltage across the voltage is rectified to obtain a rectified voltage having a positive phase, and the rectified voltage is output from the third and fourth common contacts N3, N4.

Explaining in more detail, the bridge circuit 2 has a first to fourth rectifiers 21, 22, 23, 24. The first rectifier 21 is electrically connected between the first and third common contacts N1, N3, and the second rectifier 22 is electrically connected between the first and fourth common contacts N1, N4, the third rectifier 23 is electrically connected between the second and third common contacts N2, N3, and the fourth rectifier 24 is electrically connected between the second and fourth common contacts N2, N4. In the preferred embodiment, the first to fourth rectifiers 21, 22, 23, and 24 are each a diode, and the anode of the first rectifier 21 and the second rectifier 22 are The cathode is electrically connected to the first common contact N1, the anode of the third rectifier 23 and the cathode of the fourth rectifier 24 are electrically connected to the second common contact N2, the cathode of the first rectifier 21 and the third The cathode of the rectifier 23 is electrically connected to the third common contact N3, and the anode of the second rectifier 22 and the anode of the fourth rectifier 24 are electrically connected to the fourth common contact N4.

The dimmer 3 is electrically connected between the third and fourth common contacts N3, N4 of the bridge circuit 2 to receive the rectified voltage, and the rectified voltage is used to generate a rectified current of a magnitude related to the rectified voltage. And the rectified current flows from the third common contact N3 through the dimmer 3 to the fourth common contact N4.

The dimmer 3 has a time delay unit 31 and a switch unit 32.

The time delay unit 31 performs conversion based on the rectified current and a time delay value to generate a switching voltage.

The time delay unit 31 has a variable resistor 311, a fixed resistor 312, a capacitor 313, and a discharge element 314.

The variable resistor 311 and the fixed resistor 312 are connected in series between the third common contact N3 and a fifth common contact N5.

The capacitor 313 is electrically connected between the fourth and fifth common contacts N4 and N5, and the fifth common contact N5 generates the switching voltage, wherein the time delay value is related to the variable resistor 311 value, and the fixed The value of the resistor 312 and the value of the capacitor 313.

The anode of the discharge element 313 is electrically connected to the fifth common contact N5, and the cathode is electrically connected to the third common contact N3.

The switch unit 32 has a first end and a second end electrically connected to the third and fourth common contacts N3, N4, respectively, and a control end electrically connected to the time delay unit 31 to receive the switch voltage. And the switch unit 32 determines whether to turn on between the first and second ends of the switch unit 32 according to whether the switch voltage is greater than a predetermined turn-on value. The switch unit 32 has a switching element 321 and a trigger element 322.

The switching element 321 has a first end electrically connected to the third common contact N3, a second end electrically connected to the fourth common contact N4, and a first end and a second end. Whether the control terminal is turned on. In the preferred embodiment, the switching element 321 is a voltage controlled rectifier (SCR).

The triggering component 322 is electrically connected between the fifth common contact N5 and the control terminal of the switching component 321 , and the triggering component 322 is higher than a conducting bias voltage between the two ends of the triggering component 322 . Turning on, the potential of the fifth common contact N5 is applied to the control terminal of the switching element 321 and the switching element 321 is turned on.

In the preferred embodiment, the triggering component 322 is a Shockley Diode, and the anode of the Schaucle diode is electrically connected to the fifth common junction N5, and the cathode is electrically connected to the switching component. The control end of 321 .

The illuminating load 20 is driven by the first cross-pressure to emit light.

Referring to FIG. 8, the first voltage across the voltage V _L applied to the light-emitting load 20, the rectified voltages V _N3-N4 applied to the third and fourth common contacts N3, _N4 , and the third common connection A current I _N3-N4 flowing through the dimmer 3 to the fourth common contact N4 follows the change waveform of the alternating voltage V _AC , and it is worth noting that the first cross voltage V _L shown in FIG. The light-emitting load 20 is measured based on a resistive load or a resistive load. If the non-resistive load is used, the waveform of the first cross-voltage V _L may be slightly different. In addition, due to the first and fourth rectifiers The magnitude of the forward bias voltage of 21, 22, 23, and 24 is much smaller than the magnitude of the AC voltage V _AC , so the rectified voltage V _N3-N4 shown in FIG. 8 ignores the first and fourth rectifiers 21, The result of the forward bias of 22, 23, and 24.

Referring to FIG. 8 and FIG. 9, from time t0 to time t1, the alternating voltage V _AC is larger than the total of the first and fourth rectifier timely forward conduction bias 21 and 24, of the first and fourth rectifier 21, 24 is turned on, the rectified current I _AC starts to charge the capacitor 313, and the flow direction of the rectified current I _AC is sequentially from the first common contact N1, the first rectifier 21, the third common contact N3, The fixed resistor 312, the variable resistor 311, the capacitor 313, the fourth common contact N4, the fourth rectifier 24, and the second common contact N2 finally flow through the illuminating load 20, and thus the third common The potential of the contact N3 is higher than the potential of the fifth common contact N5, so that the reverse bias of the discharge element 314 is not turned on at this time. In addition, at time t0 to time t1, the switching voltage across the capacitor 313 is not yet large enough to turn on the switching element 321 and the triggering element 322, and the rectification between the third and fourth common contacts N3, N4 voltage V _N3-N4 much greater than the load applied to the emission of the first cross voltage V _L 20, so FIG. 8 shows the first cross voltage V _L from the time t0 to the time t1 is substantially zero, the rectified voltage V _{N3 -N4} is changed in _accordance with the AC voltage V _AC .

Referring to FIG. 8 and FIG. 10, from time t1 to time t2, the switching voltage across the capacitor 313 has increased with time to enable the switching element 321 and the triggering element 322 to be turned on, and is applied to the illuminating load 20 at this time. The first voltage across the voltage V _{L is} much larger than the rectified voltage V _N3-N4 between the third and fourth common contacts N3, _N4 , and since the rectified voltage V _{N3-N4 is} opposite to the first cross voltage V at this time _{L is} much smaller, so the rectified voltage V _{N3-N4 of} FIG. 8 approaches zero from time t1 to time t2, and the first cross-over voltage V _{L changes} in accordance with the alternating voltage V _AC . And from time t1 to time t2, the switching voltage across the capacitor 313 is also greater than the series conduction bias of the discharge element 314 and the switching element 321, so that the discharge element 314 is turned on, and the charge stored by the capacitor 313 is transmitted through the discharge. Element 314 is discharged until time t2 that the switching voltage across capacitor 313 has decreased over time to cause switching element 321 and trigger element 322 to switch non-conducting.

Referring to FIG. 8 and FIG. 11 , the operation mode of the symmetrical dimming module 10 approximates the operation mode from time t0 to time t1 from time t2 to time t3, so the first cross-pressure V _L shown in FIG. 8 is The time t2 to the time t3 is substantially zero, and the rectified voltage V _N3-N4 is changed in accordance with the alternating voltage V _AC .

Referring to FIG. 8 and FIG. 12, from time t3 to time t4, the operation mode of the symmetrical dimming module 10 approximates the operation mode from time t1 to time t2, so the rectified voltage V _N3-N4 shown in FIG. 8 is The time t3 to the time t3 is close to zero, and the first cross-voltage V _L is changed following the AC voltage V _AC .

Referring to Figure 13, a second preferred embodiment of the illumination device of the present invention is similar to the first preferred embodiment, with the difference that the triggering element 322 is A two-way trigger is used, but only one-way triggering is required.

Referring to FIG. 14 , a third preferred embodiment of the illuminating device of the present invention is similar to the first preferred embodiment. The difference is that the symmetrical dimming module 10 of the third preferred embodiment further includes a The inductor 4 of the high frequency noise, and one end of the inductor 4 is electrically connected to the AC power source 30, and the other end is electrically connected to the first common contact N1.

Referring to FIG. 15 , a fourth preferred embodiment of the illuminating device of the present invention is similar to the third preferred embodiment. The difference is that the symmetrical dimming module 10 further includes a damper circuit 5 . It is used to eliminate the resonance caused by the inductor 4 and the capacitor 313.

The damper circuit 5 has a resistor 51 and a capacitor 52 connected in series between the third and fourth common contacts N3, N4.

In summary, the above preferred embodiment has the following advantages: the bridge circuit 2 causes the phase of the alternating voltage V _AC to change anyway, and the rectified current I _{AC is} constantly symmetrical from the third common contact N3. The illuminator 3 flows to the fourth common contact N4. Therefore, the positive and negative polarities of the switching voltage across the capacitor 313 do not change with the phase corresponding to the AC voltage V _AC , so the trigger component 322 has only one-way trigger conduction. The operation mode can avoid the disadvantages of the prior art that the bidirectional trigger diode 14 is bidirectionally triggered to generate a positive and negative half cycle conduction phase angle asymmetry, so that the flicker can be reduced to achieve the object of the present invention.

However, the above is only the preferred embodiment of the present invention, and the scope of the present invention cannot be limited thereto, that is, the simple equivalent change and repair according to the scope of the patent application and the patent specification of the present invention. Decorations are still within the scope of the invention patent.

2‧‧‧Bridge Circuit

21‧‧‧First rectifier

22‧‧‧Second rectifier

23‧‧‧ Third rectifier

24‧‧‧fourth rectifier

N1‧‧‧ first common joint

N2‧‧‧ second common joint

N3‧‧‧ third common joint

N4‧‧‧ fourth common joint

N5‧‧‧ fifth common joint

3‧‧‧Dimmer

31‧‧‧Time delay unit

311‧‧‧Variable resistor

312‧‧‧ Fixed resistor

313‧‧‧ Capacitance

314‧‧‧discharge element

32‧‧‧Switch unit

321‧‧‧Switching elements

322‧‧‧ Trigger components

10‧‧‧Symmetric dimming module

20‧‧‧Lighting load

30‧‧‧AC power supply

V _AC ‧‧‧AC voltage

i _AC ‧‧‧AC current

Claims (10)

A symmetrical dimming module is adapted to be connected in series with an AC power source and an illuminating load for providing an AC voltage, and the AC voltage from the AC power source is divided into a first voltage and an application applied to the illuminating load. The second voltage across the symmetrical dimming module includes: a bridge circuit including a first and second common contacts for receiving the second voltage, and a first And a fourth common contact, and the bridge circuit rectifies the second voltage across the voltage to obtain a rectified voltage with a positive phase, and outputs the rectified voltage from the third and fourth common contacts; An optical device electrically connected between the third and fourth common contacts of the bridge circuit to receive the rectified voltage, and using the rectified voltage to generate a rectified current having a magnitude related to the rectified voltage, and the rectified current is constant The third common contact flows to the fourth common contact through the dimmer, wherein the dimmer includes: a time delay unit, and performs conversion according to the rectified current and a time delay value to generate a switching voltage; And a switch a first and a second end electrically connected to the third and fourth common contacts, and a control end electrically connected to the time delay unit to receive the switching voltage, and the switching unit is Whether the switching voltage is greater than a predetermined conduction value determines whether the first and second ends of the switching unit are turned on. The symmetric dimming module of claim 1, wherein the time delay unit has: a variable resistor, a fixed resistor and a capacitor; the variable resistor and the fixed resistor are connected in series between the third common contact and a fifth common contact; and the capacitor is electrically connected to the fourth and fifth The switching voltage is generated between the common contacts, and the fifth common contact is related to the variable resistance value, the fixed resistance value, and the capacitance value. The symmetric dimming module of claim 2, wherein the switching element is a controlled rectifier. The symmetrical dimming module of claim 2, wherein the switch unit has: a switching element having a first end electrically connected to the third common contact and an electrical connection to the fourth common connection a second end of the point, and a control end for controlling whether the first end and the second end are conductive; and a triggering component electrically connected between the fifth common contact and the control end of the switching element, When a voltage across the trigger element is higher than a conduction bias, the trigger element is turned on, and the potential of the fifth common contact is applied to the control terminal of the switching element and the switching element is turned on. The symmetrical dimming module of claim 4, wherein the triggering element is a Schuler diode. The symmetric dimming module of claim 4, wherein the triggering component is a bidirectional triggering diode. The symmetrical dimming module of claim 1, further comprising an inductor, one end of the inductor for receiving or outputting the alternating current, and the other end electrically connected to the first common contact. The symmetrical dimming module of claim 7, further comprising a snubber circuit having a resistor and a capacitor connected in series between the third and fourth common contacts. The symmetrical dimming module of claim 1, wherein the bridge circuit comprises: a first rectifier electrically connected between the first and third common contacts; and a second rectifier electrically connected to Between the first and fourth common contacts; a third rectifier electrically connected between the second and third common contacts; and a fourth rectifier electrically connected to the second and fourth common contacts between. A illuminating device, which is adapted to be connected in series with an AC power source, the AC power source providing an AC voltage, the lighting device comprising: the symmetric dimming module of any one of the preceding claims 1 to 9; a light-emitting load, in series with the AC power source and the symmetrical dimming module, dividing the AC voltage from the AC power source into a first voltage across the illuminating load and applying to the symmetrical dimming mode A second voltage across the set, and the first voltage across the drive drives the illumination load to illuminate.