JP2020107434A - Power supply and lighting system - Google Patents

Abstract

To expand an output voltage adjustment range.SOLUTION: A power supply 1 includes a DC conversion unit 2 that converts a first DC voltage V1 into a second DC voltage V2, and a control unit 3 that controls the DC conversion unit 2 to adjust a second DC voltage V2. The DC conversion unit 2 includes a resonant converter 20 having a transformer T1 for output, and a winding ratio adjusting unit 21 that adjusts the winding ratio of the transformer T1. The control unit 3 adjusts the second DC voltage V2 by changing the operating frequency f of the resonant converter 20. The control unit 3 causes the winding ratio adjusting unit 21 to adjust the winding ratio of the transformer T1.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to a power supply device and a lighting system, and more particularly, to a power supply device having a variable output voltage and a lighting system including the power supply device.

As a conventional example, an LED lighting device (power supply device) described in Patent Document 1 will be illustrated. The LED lighting device described in Patent Document 1 includes a PFC circuit for power factor improvement, and a current resonance converter circuit that receives a constant DC voltage output from the PFC circuit as an input. The current resonance converter circuit alternately switches the DC voltage by the first switching element and the second switching element, and resonates by the inductor component of the first inductor and the second inductor and the capacitor component of the first capacitor. The current resonance converter circuit is composed of a circuit that transmits inductive power corresponding to the magnetic flux generated in the second inductor to the third inductor and rectifies it by the diode bridge. The LED lighting device of the conventional example can dimm the LED by changing the oscillation frequency of the current resonance converter circuit (the switching frequency of the first and second switching elements).

JP, 2005-149136, A

The output voltage of the current resonance converter circuit of the above-mentioned conventional example decreases as the oscillation frequency thereof becomes higher (as it goes away from the resonance frequency). However, the oscillation frequency of the current resonance converter circuit can be changed only up to the upper limit frequency according to the ability of the drive circuit that drives the first and second switching elements. Therefore, in the above-mentioned conventional example, it was difficult to widen the dimming range (adjustment range of the output voltage) of the LED.

An object of the present disclosure is to provide a power supply device and a lighting system capable of expanding the adjustment range of the output voltage.

A power supply device according to an aspect of the present disclosure includes a DC converter that converts a first DC voltage into a second DC voltage, and a controller that controls the DC converter to adjust the second DC voltage. Equipped with. The DC converter includes a resonance converter having a transformer for output, and a turns ratio adjuster that adjusts the turns ratio of the transformer. The controller adjusts the second DC voltage by changing the operating frequency of the resonant converter. The controller causes the turns ratio adjuster to adjust the turns ratio of the transformer.

A lighting system according to an aspect of the present disclosure includes a plurality of the power supply devices, a plurality of lighting loads, and a power feeding path for supplying DC power output from the plurality of power supply devices to the plurality of lighting loads. Prepare The plurality of power supply devices are electrically connected in parallel to the first end of the power feeding path. The plurality of lighting loads are electrically connected in parallel or in series to the second end of the power feeding path.

The power supply device and the lighting system according to the present disclosure have an effect that the adjustment range of the output voltage can be expanded.

FIG. 1 is a circuit configuration diagram of a power supply device according to an embodiment of the present disclosure. FIG. 2 is a diagram showing an output characteristic of the resonant converter in the power supply device of the above. FIG. 3 is a diagram showing the relationship between the operating frequency and the dimming level of the resonant converter in the above power supply device. FIG. 4 is a system configuration diagram of the lighting system according to the embodiment of the present disclosure. FIG. 5: is a circuit block diagram of the lighting fixture in the lighting system same as the above. FIG. 6 is a circuit configuration diagram of the above illumination system. FIG. 7 is a diagram showing the relationship between the operating frequency and the dimming level of the resonant converter in the above illumination system. FIG. 8 is a system configuration diagram of a modified example of the above illumination system.

Embodiments of a power supply device and an illumination system according to the present invention will be described in detail with reference to the drawings. However, the drawings described in the embodiments below are schematic views, and the respective ratios of the sizes and thicknesses of the respective constituent elements do not necessarily reflect the actual dimensional ratios. The configurations described in the embodiments below are merely examples of the present disclosure. The present disclosure is not limited to the following embodiments, and various modifications can be made according to the design and the like as long as the effects of the present disclosure can be exhibited.

The power supply device 1 (hereinafter, abbreviated as the power supply device 1) according to the embodiment includes a DC conversion unit 2 and a control unit 3 as illustrated in FIG. 1. The DC converter 2 converts (steps up or steps down) the first DC voltage V1 input from the constant voltage source 12 into the second DC voltage V2. The controller 3 controls the DC converter 2 to change the second DC voltage V2. The control unit 3 has, for example, a microcontroller. The control unit 3 executes various programs by the microcontroller to perform various controls described later.

The power supply device 1 applies the second DC voltage V2 output from the DC converter 2 to a plurality of lighting loads (two lighting fixtures 4 in the illustrated example). The two lighting fixtures 4 are turned on when the second DC voltage V2 is applied. The two lighting fixtures 4 are electrically connected to the power supply device 1 in series. Therefore, the second DC voltage V2 must be higher than the sum of the lighting start voltages of the two lighting fixtures 4. In the power supply device 1, the control unit 3 controls the DC conversion unit 2 based on a command received from the controller 8 via the signal line 80, adjusts the second DC voltage V2, and dims each lighting fixture 4. To do. In the following description, the two lighting fixtures 4 may be referred to as a first lighting fixture 4A and a second lighting fixture 4B.

The DC converter 2 has a resonant converter 20 and a turns ratio adjuster 21. The resonant converter 20 is a so-called LLC current resonant converter. The resonance converter 20 includes a half bridge circuit in which two switching elements Q1 and Q2 are electrically connected in series, resonance capacitors C1 and C2 and an inductor L1, a transformer T1, a rectifier circuit DB, and a smoothing circuit. And a capacitor C3. The two switching elements Q1 and Q2 are N-channel enhancement type MOSFETs (metal-oxide-semiconductor field-effect transistors). However, the switching elements Q1 and Q2 may be power transistors other than MOSFETs such as bipolar transistors. Further, the resonance converter 20 may have a full bridge circuit in which four switching elements are bridge-connected, instead of the half bridge circuit.

Resonance capacitors C1 and C2, an inductor L1, and an input winding N1 of a transformer T1 are electrically connected to the switching element Q2 of the lower arm. The transformer T1 has three output windings (first output winding N21, second output winding N22 and third output winding N23) and three taps (first tap X1, second tap X2 and third tap). With taps X3). The first tap X1 is provided at the first end of the first output winding N21, and the second tap X2 is provided at the connection portion between the second end of the first output winding N21 and the first end of the second output winding N22. Has been. The third tap X3 is provided at a connection point between the second end of the second output winding N22 and the first end of the third output winding N23. The second end of the third output winding N23 is electrically connected to the second AC input terminal K12 of the rectifier circuit DB. A smoothing capacitor C3 is electrically connected between the pulsating current output terminals K21 and K22 of the rectifier circuit DB.

The turn ratio adjusting unit 21 has three switches (first switch S1, second switch S2, and third switch S3) and a switch drive circuit 210 that drives these three switches.

The first switch S1, the second switch S2, and the third switch S3 are each configured by an electromagnetic relay or a solid state relay (SSR: Solid State Relay). The first switch S1 is inserted between the first tap X1 and the first AC input terminal K11 of the rectifier circuit DB. The second switch S2 is inserted between the second tap X2 and the first AC input terminal K11 of the rectifier circuit DB. The third switch S3 is inserted between the third tap X3 and the first AC input terminal K11 of the rectifier circuit DB.

The switch drive circuit 210 selectively turns on the first switch S1, the second switch S2, and the third switch S3 in response to an instruction from the control unit 3. When the switch drive circuit 210 turns on the first switch S1, the turns ratio of the transformer T1 is adjusted to the highest turns ratio (first turns ratio). When the switch drive circuit 210 turns on the third switch S3, the turns ratio of the transformer T1 is adjusted to the lowest turns ratio (third turns ratio). Further, when the switch drive circuit 210 turns on the second switch S2, the turns ratio of the transformer T1 is adjusted to a middle turns ratio (second turns ratio) between the first turns ratio and the third turns ratio. That is, the turns ratio adjusting unit 21 selectively turns on the first switch S1, the second switch S2, and the third switch S3 in the switch drive circuit 210 to change the turns ratio of the transformer T1 to the first turns ratio, It is possible to adjust to three kinds of winding ratios of the second winding ratio and the third winding ratio.

In the resonant converter 20, the two switching elements Q1 and Q2 are complementarily switched by the drive circuit 22. The control unit 3 converts the first DC voltage V1 into a rectangular pulse voltage by performing PFM (Pulse Frequency Modulation) control of the two switching elements Q1 and Q2 via the drive circuit 22. The rectangular pulse voltage is converted into a sinusoidal voltage having a frequency corresponding to the switching frequency of PFM control by the series resonance circuit of the resonance capacitors C1 and C2, the inductor L1 and the input winding N1 of the transformer T1. To be done. The sine wave voltage is transformed by the transformer T1, full-wave rectified by the rectifier circuit DB, smoothed by the capacitor C3, and converted into the second DC voltage V2. The voltage after being transformed by the transformer T1 (secondary voltage of the transformer T1) increases as the winding ratio of the transformer T1 (the number of turns of the output winding/the number of turns of the input winding) increases. ..

Here, the resonant converter 20 has the output characteristic shown by the solid line in FIG. The horizontal axis of FIG. 2 represents the operating frequency f of the resonant converter 20 (the frequency at which the drive circuit 22 switches the switching elements Q1 and Q2). The vertical axis of FIG. 2 represents the output ratio (V2/V1) of the resonant converter 20. The output ratio of the resonant converter 20 becomes maximum when the operating frequency f matches the resonant frequency f0 of the series resonant circuit, and decreases as the operating frequency f moves away from the resonant frequency f0. Therefore, in the power supply device 1, by changing the operating frequency f of the resonant converter 20 in the frequency range FA (the range from the first frequency f1 to the second frequency f2) higher than the resonant frequency f0, the second DC Adjust the voltage V2. In addition, the control unit 3 performs PFM control of the two switching elements Q1 and Q2 via the drive circuit 22 to determine the current flowing through the lighting fixture 4 (the first lighting fixture 4A and the second lighting fixture 4B). Current control is preferred. When the resonant converter 20 is operated at an operating frequency f lower than the resonant frequency f0, a through current may flow through the two switching elements Q1 and Q2, and the switching elements Q1 and Q2 may be damaged.

The control unit 3 adjusts the operating frequency f via the drive circuit 22 to adjust the second DC voltage V2 based on the command (dimming level) received from the controller 8. The dimming level corresponds to the voltage ratio between the second DC voltage V2 output from the power supply device 1 and the rated voltage of the lighting fixture 4. That is, the dimming level when the second DC voltage V2 is equal to the rated voltage of the lighting fixture 4 becomes 100%, and as the second DC voltage V2 decreases, the dimming level decreases and the light quantity of the lighting fixture 4 decreases. Decrease.

By the way, the adjustable range of the output ratio corresponding to the frequency range FA (output variable range VA: see FIG. 2) is narrower than the dimmable range of the lighting fixture 4. Therefore, when the operating frequency f of the resonant converter 20 is set to the upper limit frequency (second frequency f2) in the turn ratio when the second DC voltage V2 does not reach the voltage corresponding to the dimming level, It is preferable that the turns ratio adjuster 21 adjust the turns ratio. The control unit 3 adjusts the winding ratio of the transformer T1 by the winding ratio adjusting unit 21, so that the adjustable range of the dimming level can be expanded without expanding the frequency range FA.

For example, as shown in FIG. 3, when the dimming level is adjusted in the range of 100% to 66%, the control unit 3 causes the turns ratio adjusting unit 21 to set the turns ratio of the transformer T1 to the highest first turns ratio. To adjust. In other words, when the turns ratio of the transformer T1 is adjusted to the first turns ratio, the adjustable dimming level range within the frequency range FA of the operating frequency f is limited to 100% to 66%. However, when the turns ratio of the transformer T1 is adjusted to the second turns ratio, the second DC voltage V2 output in the frequency range FA of the operating frequency f decreases, so the adjustable dimming level range. Also falls to 66% to 33%. Further, when the turns ratio of the transformer T1 is adjusted to the third turns ratio, the second DC voltage V2 output within the frequency range FA of the operating frequency f is further reduced, so that the adjustable dimming level is adjusted. The range also drops to 33%-22% (see Figure 3).

Here, the control unit 3 stores in the memory (nonvolatile semiconductor memory) a data table representing a combination of the turns ratio of the transformer T1 and the operating frequency f corresponding to the dimming level in the range of 100% to 22%. Preferably. When the control unit 3 receives the command (dimming level) from the controller 8, the control unit 3 reads a combination of the turns ratio of the transformer T1 and the operating frequency f corresponding to the dimming level from the data table. The control unit 3 controls the turn ratio adjusting unit 21 to adjust the turn ratio of the transformer T1 read from the data table and matches the operating frequency f of the resonant converter 20 with the operating frequency f read from the data table. Let As a result, the power supply device 1 adjusts the turns ratio of the transformer T1 by the turns ratio adjusting unit 21 to increase the second DC voltage V2 without expanding the frequency range FA of the operating frequency f of the resonant converter 20. The adjustment range (adjustment range of dimming level) can be expanded.

Next, the illumination system 5 according to the embodiment will be described in detail with reference to the drawings. As shown in FIG. 4, the lighting system 5 includes a plurality of (three in the illustrated example) lighting fixtures 4 and a lighting unit 10.

The three luminaires 4 are, for example, floodlights used for illuminating a stadium, and are installed at the tip (high place) of an illumination column or the like. In the following description, the three lighting fixtures 4 may be referred to as a first lighting fixture 4A, a second lighting fixture 4B, and a third lighting fixture 4C.

As shown in FIG. 5, each of the three lighting fixtures 4 includes a plurality of LED modules 40 (two in the illustrated example) in which a plurality of (three in the illustrated example) LEDs (Light Emitting Diodes) 41 are connected in series in the forward direction. ) Have. These three lighting fixtures 4 are electrically connected in series. As described above, it is preferable that each of the lighting fixtures 4 has a plurality (for example, two) of LED modules 40 in order to reduce the rated voltage, and these plurality of LED modules 40 are electrically connected in parallel ( (See FIG. 5). If each lighting fixture 4 is configured as described above, the luminous flux can be increased without changing the rated voltage. However, it is preferable that the plurality of LEDs 41 included in the LED module 40 have the same VF rank. That is, if a plurality of LED modules 40 made of the same manufacturer and belonging to the same VF rank constitute a plurality of LED modules 40, it is possible to suppress variations in forward voltage (variations in rated voltage). The lighting fixture 4 may have a solid-state light source such as an organic electroluminescence element (also referred to as OLED: Organic Light Emitting Diode) or a semiconductor laser instead of the LED 41. However, the solid-state light source used as the lighting load has a characteristic that the voltage-current characteristic is close to a constant voltage characteristic, such as an LED and an organic electroluminescence element (a characteristic that the ratio of the current change to the voltage change is several tens of times or more). It is preferable to have

The lighting unit 10 is installed, for example, in a building provided in a stadium. However, the number of lighting fixtures 4 and the number of lighting units 10 included in the lighting system 5 are not limited to three and one, respectively.

As shown in FIG. 4, the lighting unit 10 includes a plurality of (three in the illustrated example) power supply devices 1 and one power supply cable 6. The three power supply devices 1 are housed in a case 11. The case 11 is formed in a box shape with an electric conductor (for example, metal). The case 11 is preferably grounded at a place having a stable potential (for example, the ground).

The power cable 6 has a first power line 61 and a second power line 62, and a sheath 63 that covers these two power lines 61, 62. In the case 11, the first end of the first power supply line 61 is branched and connected to the high-potential-side output terminal of each power supply device 1 via the backflow prevention diodes D11, D12, and D13. The first end of the second power supply line 62 is branched and connected to the output terminal on the low potential side of each power supply device 1 in the case 11. Further, the second end of the first power supply line 61 is electrically connected to the positive electrode of the first lighting fixture 4A. The second end of the second power supply line 62 is electrically connected to the negative electrode of the third lighting fixture 4C. Further, the negative electrode of the first lighting device 4A is electrically connected to the positive electrode of the second lighting device 4B, and the negative electrode of the second lighting device 4B is electrically connected to the positive electrode of the third lighting device 4C. .. That is, the three lighting fixtures 4A to 4C are electrically connected in series between the second end of the first power supply line 61 and the second end of the second power supply line 62 (see FIG. 4 ).

Here, when the lighting unit 10 for lighting the floodlight is installed at a high place together with the floodlight, the maintenance work of the lighting unit 10 becomes a work at a high place, which imposes a heavy burden on a worker who performs the maintenance work. I will end up. On the other hand, in the lighting system 5, since the lighting unit 10 can be installed at a place distant from the lighting fixture 4, compared to the case where the lighting unit 10 is installed at a high place like the lighting fixture 4, maintenance work is performed. The workability of can be improved. Moreover, since one lighting unit 10 and a plurality of (three in the illustrated example) lighting fixtures 4 are connected by one power cable 6, it is possible to reduce wiring.

Further, in the lighting unit 10, the three power supply devices 1, the first power supply line 61, and the second power supply line 62 are housed in the case 11. For example, when the case 11 has a waterproof structure, it is not necessary to provide a waterproof structure for each of the plurality of power supply devices 1. As a result, the illumination system 5 can reduce the manufacturing cost for ensuring the waterproof performance. Further, in the lighting system 5, since the case 11 is formed of an electric conductor (metal), it is possible to prevent high frequency noise generated from the lighting unit 10 from leaking out of the case 11 as radiation noise.

The controller 8 is electrically connected to the lighting unit 10 via a signal line 80. The controller 8 transmits a dimming signal via the signal line 80. The controller 8 transmits, for example, a PWM (Pulse Width Modulation) signal as a dimming signal to the lighting unit 10. That is, the controller 8 instructs the lighting unit 10 on the dimming level based on the duty ratio of the dimming signal (PWM signal).

On the other hand, in the lighting unit 10, the control unit 3 of each power supply device 1 receives the dimming signal transmitted from the controller 8. The control unit 3 of the power supply device 1 reads the dimming level from the received dimming signal. The control unit 3 of the power supply device 1 adjusts the second DC voltage V2 according to the read dimming level to dimm the lighting fixture 4.

Next, a specific system configuration of the illumination system 5 will be described with reference to FIG.

The lighting system 5, for example, converts the AC power supplied from the commercial power system 7 into DC power and supplies the DC power to the lighting load (lighting fixture 4). In the following description, in order to distinguish the three power supply devices 1, they may be referred to as a first power supply device 1A, a second power supply device 1B, and a third power supply device 1C. However, among the circuit configurations of the three power supply devices 1, the DC converter 2 has already been described, and therefore the illustration and description of the circuit configuration of the DC converter 2 are omitted.

The power supply device 1 (the first power supply device 1A, the second power supply device 1B, and the third power supply device 1C) includes an AC/DC converter 13 and a filter 14 as the constant voltage source 12.

The AC/DC converter 13 includes, for example, a rectifier circuit, a smoothing capacitor, and a boost chopper circuit (power factor correction circuit). The AC/DC converter 13 outputs the constant DC-converted first DC voltage V1 to the DC converter 2 by PWM control of the switching element of the boost chopper circuit by the controller 3. However, the first DC voltage V1 output from the AC/DC converter 13 can be adjusted by the controller 3.

The filter 14 filters noise (normal mode noise and common mode noise) input from the power system 7 to the power supply device 1 and noise output from the AC/DC converter 13 to the power system 7.

It should be noted that instead of each of the three power supply devices 1 including one AC/DC converter 13 and one filter 14, the three power supply devices 1 may share one AC/DC converter 13 and filter 14.

The first power supply device 1A, the second power supply device 1B, and the third power supply device 1C may share one control unit 3 (see FIG. 6).

By the way, the control unit 3 causes the winding ratio adjusting unit 21 to adjust the winding ratio when the second DC voltage V2 does not reach the target voltage even if the operating frequency f is adjusted to the second frequency f2, and It is preferable to control the AC/DC converter 13 to adjust the first DC voltage V1. For example, when the turns ratio of the transformer T1 is adjusted to the third turns ratio, even if the operating frequency f is set to the upper limit (second frequency f2) of the frequency range FA, the dimming level (second DC voltage V2) cannot be reduced below 22%. Therefore, the control unit 3 controls the AC-DC converter 13 to reduce the first DC voltage V1. If the first DC voltage V1 decreases, the control unit 3 adjusts the operating frequency f within the frequency range FA with the turns ratio of the transformer T1 set to the third turns ratio, thereby adjusting the dimming level to 22. It can be adjusted in the range of 5% to 5% (see FIG. 7).

As described above, the power supply device 1 adjusts the first DC voltage V1 by the AC/DC converter 13 to adjust the second DC voltage that is adjustable by the turns ratio of the transformer T1 and the operating frequency f of the resonant converter 20. The range of V2 can be expanded.

Here, a system configuration of a modified example of the illumination system 5 will be described with reference to FIG. In a lighting system 5 of a modified example shown in FIG. 8, three lighting fixtures 4 are electrically connected in parallel to the lighting unit 10 via one power cable 6. The second DC voltage to be output to the three lighting fixtures 4 when the three lighting fixtures 4 are electrically connected in parallel as compared with the case where the three lighting fixtures 4 are electrically connected in series. V2 can be lowered.

As described above, the power supply device (1) according to the first aspect includes a DC converter (2) that converts the first DC voltage (V1) into a second DC voltage (V2), and a DC converter (2). ) To control the second DC voltage (V2). The DC converter (2) has a resonant converter (20) having a transformer (T1) for output, and a turns ratio adjuster (21) for adjusting the turns ratio of the transformer (T1). The control unit (3) adjusts the second DC voltage (V2) by changing the operating frequency (f) of the resonant converter (20). The control unit (3) causes the turn ratio adjusting unit (21) to adjust the turn ratio of the transformer (T1).

In the power supply device (1) according to the first aspect, an output voltage (second voltage) that can be adjusted by adjusting the operating frequency (f) of the resonant converter (20) by changing the turns ratio of the transformer (T1). It is possible to expand the adjustment range of the DC voltage (V2).

The power supply device (1) according to the second aspect can be realized by a combination with the first aspect. In the power supply device (1) according to the second aspect, the control unit (3) sets the operating frequency (f) of the resonant converter (20) as the upper limit frequency (second frequency f2) in the winding ratio. When the DC voltage (V2) does not reach the target voltage, it is preferable that the turns ratio adjuster (21) adjust the turns ratio.

The power supply device (1) according to the second aspect can maximize the adjustment range of the second DC voltage (V2) with respect to the adjustment range of the operating frequency (f).

The power supply device (1) according to the third aspect can be realized by a combination with the first or second aspect. In the power supply device (1) according to the third aspect, the resonant converter (20) preferably has a rectifier circuit (DB) that rectifies the AC voltage output by the transformer (T1). The transformer (T1) preferably has an output winding (N21; N22; N23) provided with one or more taps (X1; X2; X3). It is preferable that the turn ratio adjusting unit (21) selectively switches between a connected state where one or more taps and an input terminal of the rectifier circuit (DB) are electrically connected and a non-connected state where they are not electrically connected.

The power supply device (1) according to the third aspect can easily adjust the winding ratio by the winding ratio adjusting unit (21).

The power supply device (1) according to the fourth aspect can be realized by a combination with any one of the first to third aspects. The power supply device (1) according to the fourth aspect preferably includes an AC/DC converter (13) that converts an AC voltage input from the power system (7) into a first DC voltage (V1). The control unit (3) preferably controls the AC-DC conversion unit (13) to adjust the first DC voltage (V1).

The power supply device (1) according to the fourth aspect adjusts the first DC voltage (V1) to adjust the output frequency (second voltage) that is adjustable by adjusting the operating frequency (f) of the resonant converter (20). It is possible to further expand the adjustment range of the DC voltage (V2).

The power supply device (1) according to the fifth aspect can be realized by a combination with the fourth aspect. In the power supply device (1) according to the fifth aspect, the control unit (3) sets the second DC voltage (V2) to the operating frequency (f) of the resonant converter (20) even when the upper limit frequency in the turns ratio is set. When the target voltage is not reached, it is preferable that the turns ratio adjuster (21) adjust the turns ratio. Even when the operating frequency (f) of the resonance converter (20) is set to the upper limit frequency in the turns ratio, if the second DC voltage (V2) does not reach the target voltage, the control unit (3) causes the AC/DC converter. It is preferable to control (13) to adjust the first DC voltage (V1).

The power supply device (1) according to the fifth aspect can maximize the adjustment range of the second DC voltage (V2) with respect to the adjustment range of the operating frequency (f).

The power supply device (1) according to the sixth aspect can be realized by a combination with the fourth aspect. In the power supply device (1) according to the sixth aspect, the control unit (3) determines that the second DC voltage (V2) is equal to the operating frequency (f) of the resonant converter (20) even if the second DC voltage (V2) is the upper limit frequency in the turns ratio. When the target voltage is not reached, it is preferable to control the AC/DC converter (13) to adjust the first DC voltage (V1).

The power supply device (1) according to the sixth aspect can maximize the adjustment range of the second DC voltage (V2) with respect to the adjustment range of the operating frequency (f).

A lighting system (5) according to a seventh aspect includes a plurality of power supply devices (1) according to any one of the first to sixth aspects. A lighting system (5) according to a seventh aspect includes a plurality of lighting loads (lighting equipment 4) and a power feeding path (power supply for supplying DC power output from the plurality of power supply devices (1) to the plurality of lighting loads. Cable 6). The plurality of power supply devices (1) are electrically connected in parallel to the first end of the power feeding path. The plurality of lighting loads are electrically connected in parallel or in series to the second end of the power feeding path.

In the lighting system (5) according to the seventh aspect, the adjustment range of the output voltage (second DC voltage (V2)) that can be adjusted by adjusting the operating frequency (f) of the resonant converter (20) is expanded. be able to.

The illumination system (5) according to the eighth aspect can be realized in combination with the seventh aspect. In the lighting system (5) according to the eighth aspect, it is preferable that the plurality of lighting loads be electrically connected in series to the second end of the power feeding path. It is preferable that each of the plurality of lighting loads has a plurality of solid-state light sources (LEDs 41). It is preferable that some of the plurality of lighting loads have a plurality of solid-state light source modules (LED modules 40) in which some of the plurality of solid-state light sources are electrically connected in series. It is preferable that a plurality of solid-state light source modules are electrically connected in parallel.

The lighting system (5) according to the eighth aspect can increase the luminous flux emitted from each lighting load without changing the rated voltage of each lighting load.

1 Power Supply Device 2 DC Converter 3 Control Unit 4 Lighting Equipment (Lighting Load)
5 Lighting system 6 Power cable (power supply line)
7 Power System 13 AC/DC Converter 20 Resonant Converter 21 Turns Ratio Adjuster 40 LED Module (Solid Light Source Module)
41 LED (solid-state light source)
T1 transformer N21 first output winding (output winding)
N22 Second output winding (output winding)
N23 Third output winding (output winding)
X1 1st tap (tap)
X2 2nd tap (tap)
X3 3rd tap (tap)
DB rectifier circuit f operating frequency f2 second frequency (upper limit frequency)
V1 first DC voltage V2 second DC voltage

Claims (8)

A DC converter that converts the first DC voltage into the second DC voltage;
A controller for controlling the DC converter to adjust the second DC voltage;
Equipped with
The DC converter is
A resonant converter having a transformer for output;
A turns ratio adjusting unit for adjusting the turns ratio of the transformer,
Have
The control unit adjusts the second DC voltage by changing the operating frequency of the resonant converter, and causes the turns ratio adjusting unit to adjust the turns ratio of the transformer.
Power supply. The controller adjusts the winding ratio to the winding ratio adjusting unit when the second DC voltage does not reach the target voltage even when the operating frequency of the resonant converter is set to the upper limit frequency in the winding ratio. Let
The power supply device according to claim 1. The resonant converter has a rectifier circuit that rectifies the AC voltage output by the transformer,
The transformer has an output winding provided with one or more taps,
The turns ratio adjusting unit selectively switches between a connection state in which the one or more taps and an input terminal of the rectifier circuit are electrically connected and a non-connection state in which they are not electrically connected,
The power supply device according to claim 1 or 2. An AC-DC converter for converting an AC voltage input from a power system into the first DC voltage,
The control unit controls the AC-DC conversion unit to adjust the first DC voltage,
The power supply device according to claim 1. The controller adjusts the winding ratio to the winding ratio adjusting unit when the second DC voltage does not reach the target voltage even when the operating frequency of the resonant converter is set to the upper limit frequency in the winding ratio. And controlling the AC-DC converter to adjust the first DC voltage,
The power supply device according to claim 4. The control unit controls the AC-DC converter to control the AC-DC converter when the second DC voltage does not reach a target voltage even when the operating frequency of the resonant converter is set to an upper limit frequency in the winding ratio. Adjust the DC voltage of
The power supply device according to claim 4. A plurality of power supply devices according to any one of claims 1 to 6 are provided, and
Multiple lighting loads,
A power supply path for supplying DC power output from the plurality of power supply devices to the plurality of lighting loads,
Equipped with
The plurality of power supply devices are electrically connected in parallel to the first end of the power supply path,
The plurality of lighting loads are electrically connected in parallel or in series to the second end of the power feeding path,
Lighting system. The plurality of lighting loads are electrically connected in series to a second end of the power feeding path,
Each of the plurality of lighting loads has a plurality of solid state light sources,
A part of the plurality of lighting loads has a plurality of solid-state light source modules in which some of the solid-state light sources are electrically connected in series,
The plurality of solid-state light source modules are electrically connected in parallel,
The lighting system according to claim 7.

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