JP2017158292A - Power supply device and lighting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power supply unit and illumination device capable of achieving high safety in a simple configuration.SOLUTION: The power supply unit includes: a power conversion part that inputs an AC voltage and outputs a DC voltage in a non-isolated manner; a control part that monitors an input of the power conversion part; and an auxiliary power supply part that produces and outputs a first output for supplying electric power activating the control part and a second output for supplying electric power activating a control circuit controlling an operation of the power conversion part by the same transformer. The auxiliary power supply part includes a signal transmission part that is provided between a drive circuit provided on the primary side of the transformer and controlling a switching element and a detection part isolated from the drive circuit and the primary side and detecting a voltage of the first output provided on the secondary side of the transformer, and that electrically isolates a signal from the detection part for transmission to the primary side.SELECTED DRAWING: Figure 2

Description

  Embodiments described herein relate generally to a power supply device and a lighting device.

  In the case of a power supply device that turns on the lighting unit, in addition to power conversion for supplying the lighting unit, a control circuit for setting the light quantity of the lighting unit by inputting a dimming signal may be mounted. .

  When the output capacity of the power supply device is large, a plurality of power supply circuits such as a PFC circuit are mounted together, and the power supply for the operation of each part becomes complicated. For this reason, the necessity for enhancing safety measures for the power supply device is increased, and the circuit configuration is complicated.

Japanese Patent No. 5715522

  The embodiment provides a highly safe power supply device and lighting device with a simple configuration.

  The power supply apparatus according to the embodiment supplies a power conversion unit that inputs an AC voltage and outputs a DC voltage without insulation, a control unit that monitors input of the power conversion unit, and power that operates the control unit And an auxiliary power supply unit that generates and outputs a first output and a second output that supplies power for operating a control circuit that controls the operation of the power conversion unit using the same transformer. The auxiliary power supply unit is provided on the primary side of the transformer, and controls the switching element. The first output provided on the secondary side of the transformer is insulated from the drive circuit and the primary side. And a signal transmission unit that is provided between the detection unit and the first side for electrically insulating a signal from the detection unit.

  In the present embodiment, the power source for the control unit that monitors the input of the power conversion unit is supplied separately from the power source that supplies the power for operating the control circuit that controls the operation of the power conversion unit. Are generated by the same transformer, a highly safe power supply device can be realized with a simple configuration.

It is a block diagram which illustrates the power supply device concerning an embodiment. It is a block diagram which illustrates the auxiliary power supply which is a part of power supply device of an embodiment. It is a substantial block diagram which illustrates the layout of each part of the power unit of an embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the size ratio between the parts, and the like are not necessarily the same as actual ones. Further, even when the same part is represented, the dimensions and ratios may be represented differently depending on the drawings.
In the present specification and drawings, the same elements as those described above with reference to the previous drawings are denoted by the same reference numerals, and detailed description thereof is omitted as appropriate.

FIG. 1 is a block diagram illustrating a power supply device according to this embodiment.
FIG. 2 is a block diagram illustrating an auxiliary power supply unit that is a part of the power supply device of this embodiment.
As illustrated in FIG. 1, the power supply device 10 according to the present embodiment includes an AC-DC conversion unit 20, a DC-DC conversion unit 30, a control unit 40, and an auxiliary power supply unit 60.

  The power supply device 10 includes AC input terminals 11a and 11b, DC output terminals 11c and 11d, and a dimming signal input terminal 11e. The power supply device 10 is connected to the AC power source 1 through AC input terminals 11a and 11b. AC power supply 1 is a commercial power supply, for example. The AC power supply 1 supplies an AC voltage having an effective value of 100 V or 200 V to the power supply device 10 at 50 Hz or 60 Hz.

  The power supply device 10 is connected to the illumination unit 80 via the DC output terminals 11c and 11d. The lighting unit 80 includes, for example, a light emitting element 82. The light-emitting element 82 is, for example, a semiconductor light-emitting element (Light Emitting Diode), an organic light-emitting element (Organic Light Emitting Diode), or the like.

  The power supply device 10 is connected to the light control device 2 through the light control signal input terminal 11e. The power supply device 10 receives the dimming signal Sd output from the dimming device 2 via the dimming signal input terminal 11e.

  The dimming signal Sd is a signal for setting the dimming degree D. The dimming degree D indicates the amount of light of the illumination unit 80 that is turned on by the power supply device 10. For example, when the dimming signal Sd indicates the minimum dimming degree Dmin, the light amount of the illumination unit 80 is minimum. When the dimming signal Sd indicates the maximum dimming degree Dmax, the light amount of the illumination unit 80 is maximum.

  The dimming device 2 generates and outputs a dimming signal Sd according to the input set value of the dimming degree D or the like. The generated dimming signal Sd may be an analog value or a digital value. The dimming signal Sd is, for example, an analog signal having a voltage value that increases in accordance with the light amount of the lighting unit 80, or a signal including data based on DALI (Digital Addressable Lighting Interface) or the like.

  The power supply device 10 receives supply of AC power from the AC power supply 1, converts the AC power into DC power, and outputs the DC power. The output DC power is supplied to the lighting unit 80. The light quantity of the illumination unit 80 is set based on the dimming signal Sd from the dimming device 2.

  In another embodiment, the lighting device 100 includes the power supply device 10 and the lighting unit 80, and the power supply device 10 and the lighting unit 80 are connected together, or the power supply device 10 and the lighting unit 80 are separate. And are electrically connected.

The configuration of each part of the power supply device 10 will be described.
The AC-DC converter 20 is connected to the AC power source 1 via AC input terminals 11a and 11b. The AC-DC converter 20 includes a rectifier circuit 21 and a power factor correction circuit (hereinafter also referred to as a PFC circuit) 22. The rectifier circuit 21 and the PFC circuit 22 are connected in cascade in this order.

  The rectifier circuit 21 rectifies the AC voltage and outputs a pulsating flow. The PFC circuit 22 inputs a pulsating flow, converts it into a boosted DC voltage, and outputs it. PFC circuit 22 includes a switching element 23, a diode 24, a coil 25, a smoothing capacitor 26, and a control circuit 27. The switching element 23 is driven by a control circuit 27 via a control terminal (for example, a gate terminal of a MOSFET). The switching element 23 switches at an on time or an off time set by the control circuit 27.

  The PFC circuit 22 operates so that the period during which the switching element 23 is turned on is long when the input pulsating voltage is low, and the period during which the switching element 23 is turned on is short when the pulsating voltage is high. Therefore, distortion of the current waveform input to the smoothing capacitor 26 is reduced, and harmonics are suppressed.

  The control circuit 27 includes a drive circuit for driving the switching element 23. For the driving circuit, the control circuit 27 operates by being supplied with a power supply voltage higher than 5 V, for example. The power supply voltage Vcc2 of the control circuit 27 is, for example, 15V with the low potential side of the smoothing capacitor 26 or the ground terminal of the switching element 23 (for example, the source terminal of the MOSFET) as a reference potential.

  The PFC circuit 22 is not limited to a step-up power supply circuit, and may be a step-up / step-down power supply circuit or a step-down power supply circuit. The PFC circuit 22 is used when the output power capacity of the AC-DC converter 20 is large, for example, when it exceeds 25 W. When the output power capacity of the AC-DC converter 20 is, for example, 25 W or less, the output of the rectifier circuit 21 may be directly connected to the smoothing capacitor 26 without using the PFC circuit 22.

  The DC-DC converter 30 is connected to the output of the AC-DC converter 20. The AC-DC converter 20 and the DC-DC converter 30 are connected in cascade. Neither the AC-DC conversion unit 20 nor the DC-DC conversion unit 30 performs insulation with respect to the AC power supply 1, and the power supply device 10 is a non-insulated power supply circuit.

  In this example, the DC-DC converter 30 is a step-down power supply circuit. The DC-DC conversion unit 30 includes a switching element 31, a diode 32, a coil 33, an output capacitor 34, and a control circuit 35. A switching element 31 and a diode 32 connected in series are connected in parallel to the output of the AC-DC converter 20. A connection node between the switching element 31 and the diode 32 is connected to one terminal of the coil 33. The other terminal of the coil 33 is connected to the DC output terminal 11 c on the high potential side via the terminal on the high potential side of the output capacitor 34. The low potential side terminal of the output capacitor 34 is connected to the low potential side DC output terminal 11d.

  The switching element 31 is an n-channel MOSFET. The control circuit 35 is connected so that a voltage for driving can be applied between the gate and source of the n-channel MOSFET. Therefore, power for operating the control circuit 35 is supplied with reference to the connection node of the switching element 31 and the diode 32, that is, the potential of the source terminal of the n-channel MOSFET. This power source is a floating power source Vcc3 that is insulated from the power source supplied for the operation of the control circuit 27 of the PFC circuit 22 described above.

  Since the control circuit 35 operates with the connection node of the switching element 31 and the diode 32 as a reference potential, a drive voltage up to Vcc3 can be applied between the gate and source of the n-channel MOSFET (switching element 31).

  Although not shown, the output current and output voltage detection circuit of the DC-DC converter 30 operates using the low potential side terminal of the smoothing capacitor 26 or the low potential side DC output terminal 11d as a reference potential. Therefore, transmission of the control signal Vd and the like supplied to the control circuit 35 is performed using a signal transmission device such as a photocoupler or a transformer.

  For example, the control unit 40 receives a dimming signal Sd supplied from the outside and converts it to a voltage value Vd corresponding to the dimming degree D included in the dimming signal Sd. The converted voltage value Vd is supplied to the DC-DC conversion unit 30, and the DC-DC conversion unit 30 sets an output current according to the dimming degree D.

  The controller 40 is connected so that the value of the input voltage Vin can be detected. The input voltage Vin is a pulsating voltage of the rectifier circuit 21 in this example. The control unit 40 is connected to an inrush current prevention circuit 50. The control unit 40 monitors the input voltage Vin. When the input voltage Vin is equal to or lower than the predetermined voltage, the control unit 40 operates the inrush current prevention circuit 50 to limit the charging current to the smoothing capacitor 26. The controller 40 stops the operation of the inrush current prevention circuit 50 when the input voltage Vin reaches a predetermined voltage value.

  The control unit 40 monitors the input voltage Vin, and stops the operation of the power supply device 10 when the input voltage Vin is abnormal. Specifically, the power of the control circuit 27 of the PFC circuit 22 is supplied via the protection switch 41, and the protection switch 41 cuts off the power supply Vcc2 when the input voltage Vin is abnormal. Since the power supply Vcc2 is not supplied to the control circuit 27 of the PFC circuit 22, the operation is stopped and the power supply device 10 is stopped.

  The control unit 40 may include other protection functions. For example, an abnormality in the output voltage of the power supply device 10 may be monitored, and the operation of the AC-DC conversion unit 20 or the DC-DC conversion unit 30 may be stopped when the abnormality occurs.

  The control unit 40 operates with a control power supply Vcc1 having a lower voltage than the PFC power supply Vcc2 and the floating power supply Vcc3 described above. The control power supply Vcc1 is, for example, 5V or 3.3V.

  Control unit 40 includes, for example, a microcomputer and a memory (not shown). The control unit 40 monitors the input voltage of the power supply device 10 according to a program stored in the memory and executes a protection operation. The control unit 40 converts the dimming signal into a control signal Vd having a voltage representing the dimming degree according to the program.

  The inrush current prevention circuit 50 is connected in series between the AC input terminal 11 a and the rectifier circuit 21. The inrush current prevention circuit 50 may be connected in series between the AC input terminal 11 b and the rectifier circuit 21. Inrush current prevention circuit 50 includes a PTC (Positive Temperature Coefficient) thermistor 51 and a relay 52. The PTC thermistor 51 and the relay 52 are connected in parallel.

  The relay 52 is operated by the protection switch 41 and stops operating. For example, the protection switch 41 is turned on or off by the drive signal D0 output from the control unit 40. When the drive signal D0 is active, the protection switch 41 is turned on and supplies the power source Vcc2 to the relay 52. Therefore, the relay 52 operates so as to close the contact. When the drive signal D0 is inactive, the protection switch 41 is turned off and the contact of the relay 52 is opened.

  The auxiliary power supply unit 60 inputs the output of the AC-DC conversion unit 20. The auxiliary power supply unit 60 generates power supplies Vcc1, Vcc2, and Vcc3 from the direct-current voltage output from the AC-DC conversion unit 20, and supplies them to each unit.

  As shown in FIG. 2, auxiliary power supply unit 60 includes, for example, a flyback power supply circuit and a voltage regulator 67. Auxiliary power supply unit 60 includes a switching element 61, a control circuit 62, and a transformer 63. The auxiliary power supply unit 60 drives the primary winding of the transformer 63 by the switching element 61 and generates a plurality of power supplies from the two secondary windings. The control power supply Vcc1 and the PFC power supply Vcc2 are generated from one secondary winding. The PFC power supply Vcc2 is generated by a diode 64 connected to the secondary winding of the transformer 63 and an output capacitor 65.

  The control power supply Vcc1 is generated by a voltage regulator 67 that receives the PFC power supply Vcc2.

  The control circuit power supply Vcc1 and the PFC power supply Vcc2 are stabilized by a feedback circuit 70 in which the primary side and the secondary side are electrically insulated. The feedback circuit 70 includes a photocoupler 71, a resistor 72, and a constant voltage diode 73. The light receiving transistor 71 a of the photocoupler 71 is connected to the control terminal of the control circuit 62. The anode terminal of the light emitting diode 71b of the photocoupler 71 is connected to the positive side of the PFC power supply Vcc2 via the resistor 72. The cathode terminal of the light emitting diode 71b of the photocoupler 71 is connected to the negative side (GND) of the PFC power supply Vcc2 via the constant voltage diode 73. The PFC power supply Vcc2 and the control power supply Vcc1 are electrically insulated by the photocoupler 71 and feed back a control signal to the control circuit 62 on the primary side.

  As will be described in detail later, for example, the reference potential on the primary side of the auxiliary power supply unit 60 is set to the terminal on the low potential side of the input capacitor 66. The low potential side terminal of the input capacitor 66 is connected to the low potential side terminal of the smoothing capacitor 26. For example, the secondary-side reference potential of the auxiliary power supply unit is set to the low-potential side terminal of the output capacitor 65. That is, the reference potential is set in each of the transformer 63 and the feedback circuit 70 of the auxiliary power supply unit 60.

  On the primary side of the transformer 63, switching operation of high voltage and large current is performed. In the power supply device 10 of the present embodiment, the reference potential on the side of the PFC power supply Vcc2 and the control power supply Vcc1 that performs signal detection for voltage stabilization is substantially separated from the reference potential on the primary side. Yes. By substantially separating the primary side and secondary side reference potentials, the PFC power supply Vcc2 and the control power supply Vcc1 can be stably generated and supplied to the respective objects. Therefore, the various protection functions operated by these power supplies are guaranteed to operate reliably.

  The floating power supply Vcc3 is generated by the other secondary winding of the transformer 63. A diode 68 and an output capacitor 69 are connected to the other secondary winding. The floating power supply Vcc3 is not stabilized by feedback, but is stabilized to some extent by cross regulation of the flyback power supply.

  Since these power supplies are generated by a plurality of secondary windings wound around the transformer of one auxiliary power supply section 60, they are started at substantially the same rising speed. As described above, the PFC power supply Vcc2 and the floating power supply Vcc3 have higher voltage values than the control power supply Vcc1. For this reason, the control power supply Vcc1 is started before the other power supplies, so that the operation of the control unit 40 is determined. Therefore, the control unit 40 can monitor other parts.

The operation of the power supply device 10 of this embodiment will be described.
FIG. 3 is a substantial block diagram illustrating the layout of each unit of the power supply device according to the embodiment.
As shown in FIG. 3, in the power supply device 10 of the present embodiment, the primary side reference potential and the secondary side reference potential of the transformer 63 are substantially separated by the transformer 63 and the photocoupler 71 of the auxiliary power supply unit 60. ing.

  On the primary side of the transformer 63, for example, the wiring layout is set so that the potential of the low potential side terminal of the smoothing capacitor 26 of the AC-DC converter 20 becomes the reference potential. Specifically, for example, the pattern for connecting the low potential side terminals of the smoothing capacitor 26 is set wider. The pattern to which the anode of the diode 32 of the DC-DC converter 30 and the low potential terminal of the output capacitor 34 are connected is arranged so as to be connected to the pattern of the smoothing capacitor 26 at a shorter distance. The reference potentials of the switching element 61 of the auxiliary power source 60, the control circuit 62, and the light receiving transistor 71a of the photocoupler 71 are connected to the primary reference potential pattern together with the low potential side terminal of the input capacitor 66.

  In the PFC power supply Vcc2 and the control power supply Vcc1 on the secondary side of the transformer 63, the wiring layout is set so that, for example, the potential of the low potential side terminal of the output capacitor 65 becomes the reference potential. For example, the light emitting diode 71b of the feedback circuit 70, the low potential side terminal of the output capacitor, the ground terminal of the voltage regulator 67, and the like are laid out so as to be connected to the secondary side reference potential at a short distance.

  On the primary side of the transformer 63, the PFC circuit 22 and the DC-DC converter 30 perform a switching operation with a high voltage and a large current, so that the influence of noise due to the switching operation is large.

  The secondary side of the transformer 63 is electrically separated by the transformer 63 in terms of power transmission, and is also electrically separated by the photocoupler 71 in terms of signal transmission. Therefore, the stabilization control of the PFC power supply Vcc2 and the control power supply Vcc1 is less affected by noise, and a stable control operation can be performed.

The operation and effect of the power supply device 10 of the present embodiment will be described.
In the power supply device 10 of the present embodiment, the control power supply Vcc1, the PFC power supply Vcc2, and the floating power supply Vcc3 are generated by the single auxiliary power supply unit 60, respectively. Can be generated and supplied to each part.

  For the PFC power supply Vcc2 and the control power supply Vcc1, the reference potential is separated in signal transmission by the transformer 63 and the photocoupler 71. Therefore, these power supplies are not easily affected by switching of high voltage and large current, and the auxiliary power supply unit 60 can stably generate the power and supply it to each part.

  As described above, in the power supply device 10 of the present embodiment, the control power can be stably supplied to the control unit 40 and the AC-DC conversion unit 20, so that the operation of the control unit 40 can be reliably performed. it can. Therefore, it is possible to reliably protect against the abnormality of the power supply device 10.

  According to the embodiment described above, a highly safe power supply apparatus and lighting apparatus can be realized with a simple structure.

  As mentioned above, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the scope of the invention described in the claims and the equivalents thereof. Further, the above-described embodiments can be implemented in combination with each other.

  DESCRIPTION OF SYMBOLS 1 AC power supply, 2 Light control device, 10 Power supply device, 20 AC-DC conversion part, 21 Rectifier circuit, 22 PFC circuit, 23 Switching element, 24 Diode, 25 Coil, 26 Smoothing capacitor, 27 Control circuit, 30 DC-DC Conversion unit, 31 switching element, 32 diode, 33 coil, 34 output capacitor, 35 control circuit, 40 control unit, 41 protection switch, 50 inrush current prevention circuit, 51 PTC thermistor, 52 relay, 60 auxiliary power supply unit, 61 switching element 62 control circuit 63 transformer 64 diode 65 output capacitor 66 input capacitor 67 voltage regulator 68 diode 69 output capacitor 70 feedback circuit 71 photocoupler 72 resistor 73 constant voltage diode , 80 lighting units, 82 light-emitting element, 100 illumination device

Claims (3)

A power converter that inputs AC voltage and outputs DC voltage without insulation;
A control unit for monitoring the input of the power conversion unit;
An auxiliary power supply unit that generates and outputs a first output for supplying electric power for operating the control unit and a second output for supplying electric power for operating a control circuit that controls the operation of the power conversion unit;
With
The auxiliary power unit is
A drive circuit provided on the primary side of the transformer for controlling a switching element; and a detection for detecting a voltage of the first output provided on the secondary side of the transformer, insulated from the drive circuit and the primary side. And a signal transmission unit that is provided between the first unit and the signal transmission unit that electrically insulates a signal from the detection unit and transmits the signal to the primary side.   The power supply apparatus according to claim 1, wherein the signal transmission unit includes a photocoupler. A power supply device according to claim 1 or 2,
A lighting load that is lit by being supplied with DC power from the power supply device;
A lighting device comprising:

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