Lighting devices and lighting fixtures

Abstract

To provide a lighting device that can suppress noise emitted externally over a wider frequency range and a lighting fixture including the same.SOLUTION: A lighting device 1 is provided with a filter circuit 2 and a lighting circuit. The filter circuit 2 has a series circuit of a first inductor circuit 21 and a capacitor circuit 23, and a second inductor circuit 22. The lighting circuit has a rectifier circuit 31A. The first inductor circuit 21, the capacitor circuit 23, the rectifier circuit 31A, and the second inductor circuit 22 are connected electrically from a pair of power feeding lines W11, W12 side in the order of the first inductor circuit 21, the capacitor circuit 23, the rectifier circuit 31A, and the second inductor circuit 22. The first inductor circuit 21 includes a first normal mode noise filter. The second inductor circuit 22 includes a second normal mode noise filter.SELECTED DRAWING: Figure 15

Description

[Technical Field]

[0001] The present disclosure relates to a lighting device and a lighting fixture. [Background technology]

[0002] The lighting device of Patent Document 1 includes a filter circuit connected to an AC power supply. A power factor correction circuit is connected to the output of the filter circuit. A lighting circuit is connected to the output of the power factor correction circuit. The output of the lighting circuit is connected to an LED module.

[0003] The filter circuit has an input capacitor connected in parallel to the AC power supply. A common mode choke coil is connected in parallel to the input capacitor. A choke coil and an output capacitor are connected in series to the common mode choke coil. The midpoint between the choke coil and the output capacitor, and the midpoint between the output capacitor and the common mode choke coil, form the output of the filter circuit. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2018-152233 Summary of the Invention [Problem to be solved by the invention]

[0005] Lighting fixtures equipped with lighting devices such as those described in Patent Document 1 are required to meet noise standards. However, noise standards tend to be revised to become stricter every year, making it necessary to suppress noise over a wider frequency range.

[0006] Therefore, there is a demand for a lighting device that can suppress noise emitted to the outside over a wider frequency range so that the lighting device can meet noise standards when installed in a lighting fixture.

[0007] An object of the present disclosure is to provide a lighting device that can suppress noise emitted to the outside over a wider frequency range, and a lighting fixture including the lighting device. [Means for solving the problem]

[0008] A lighting device according to one aspect of the present disclosure includes a filter circuit and a lighting circuit. The filter circuit is electrically connected to a pair of power supply paths that supply AC power. The lighting circuit receives the AC power from the pair of power supply paths via the filter circuit and supplies lighting power to a lighting load. The filter circuit includes a series circuit of a first inductor circuit and a capacitor circuit that is electrically connected between the pair of power supply paths, and a second inductor circuit that is electrically connected between at least one of both ends of the capacitor circuit and the lighting circuit. The lighting circuit includes a rectifier circuit that rectifies AC voltage input from the pair of power supply paths via a part of the filter circuit. The first inductor circuit, the capacitor circuit, the rectifier circuit, and the second inductor circuit are electrically connected in this order from the pair of power supply paths. . before The second inductor circuit includes a second normal mode noise filter. The first inductor circuit includes a first normal mode noise filter including a coil and a first common mode noise filter including a coil, and the coil of the first common mode noise filter and the coil of the first normal mode noise filter are electrically connected to the pair of power supply paths without being connected to a capacitor.

[0009] A lighting fixture according to one aspect of the present disclosure includes the above-described lighting device and a housing that supports the lighting device. [Effects of the Invention]

[0010] As described above, the present disclosure has the effect of being able to suppress noise emitted to the outside over a wider frequency range. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a block diagram showing a lighting device according to an embodiment. [Figure 2] FIG. 2 is a circuit diagram showing a filter circuit of the lighting device. [Figure 3] FIG. 3 is a circuit diagram showing an equivalent circuit of the filter circuit of the above embodiment. [Figure 4] FIG. 4 is a circuit diagram showing a filter circuit of the comparative example. [Figure 5] FIG. 5 is a diagram showing frequency characteristics of disturbance wave voltage in the comparative example. [Figure 6] FIG. 6 is a diagram showing frequency characteristics of interference wave voltage in the lighting device of the same. [Figure 7] FIG. 7 is a diagram showing frequency characteristics of interference wave voltage in the comparative example. [Figure 8] FIG. 8 is a diagram showing frequency characteristics of interference wave voltage in the lighting device of the same. [Figure 9] FIG. 9 is a circuit diagram showing a modification of the filter circuit of the above embodiment. [Figure 10] FIG. 10 is a circuit diagram showing a modification of the filter circuit of the above embodiment. [Figure 11] FIG. 11 is a circuit diagram showing a modification of the filter circuit of the above embodiment. [Figure 12] FIG. 12 is a circuit diagram showing a modification of the filter circuit of the above embodiment. [Figure 13] FIG. 13 is a circuit diagram showing a modification of the filter circuit of the above embodiment. [Figure 14] FIG. 14 is a circuit diagram showing a modified example of the lighting circuit of the lighting device. [Figure 15] FIG. 15 is a circuit diagram showing a modification of the filter circuit of the above embodiment. [Figure 16] FIG. 16 is a circuit diagram showing a modification of the filter circuit of the above embodiment. [Figure 17] FIG. 17 is a circuit diagram showing a modification of the filter circuit of the above embodiment. [Figure 18] FIG. 18 is a perspective view showing the configuration of a lighting fixture including the lighting device. [Figure 19] 19A and 19B are cross-sectional views showing the configuration of a lighting fixture including the lighting device of the same embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] The following embodiments relate generally to lighting devices and luminaires, and more particularly to lighting devices and luminaires that are supplied with AC power.

[0013] Hereinafter, lighting devices and lighting fixtures according to embodiments will be described in detail with reference to the drawings. However, the drawings described in the following embodiments are schematic diagrams, and the ratios of the sizes and thicknesses of the components do not necessarily reflect the actual dimensional ratios. Note that the configurations described in the following embodiments are merely examples of the present disclosure. The present disclosure is not limited to the following embodiments, and various modifications are possible depending on the design, etc., as long as the effects of the present disclosure can be achieved.

[0014] (1) Overview of the lighting device 1 converts AC power supplied from an AC power source 9 via a pair of power supply lines W11 and W12 into DC power and supplies the DC power to a lighting load 4. The lighting load 4 is lit by the DC power supplied from the lighting device 1.

[0015] The lighting load 4 has a plurality of solid-state light-emitting elements. For example, the lighting load 4 has an LED array in which a plurality of LEDs (Light Emitting Diodes) corresponding to a plurality of solid-state light-emitting elements are connected in series. Note that the lighting load 4 is not limited to a configuration having LEDs as solid-state light-emitting elements. The lighting load 4 may have other solid-state light-emitting elements, such as organic electroluminescence (OEL) elements or semiconductor laser diodes (Laser Diodes, LD). Furthermore, the number of solid-state light-emitting elements is not limited to a plurality, and may be one. The electrical connection relationship of the plurality of solid-state light-emitting elements is a series connection, but is not limited to this connection relationship. The electrical connection relationship of the plurality of solid-state light-emitting elements may be a parallel connection, or a combination of a series connection and a parallel connection.

[0016] The lighting device 1 includes a filter circuit 2 and a lighting circuit 3.

[0017] The lighting circuit 3 includes a rectifier circuit 31 and a switching circuit 32, and is supplied with AC power from a pair of power supply lines W11 and W12 via a filter circuit 2, supplying lighting power to the lighting load 4. The pair of power supply lines W11 and W12 includes conductors such as electric wires, bus bars, or circuit patterns on a circuit board.

[0018] The rectifier circuit 31 includes at least one rectifier element (such as a diode, a thyristor, or a triac) and rectifies the AC voltage V1 input from the pair of power supply lines W11 and W12 via the filter circuit 2. The rectifier circuit 31 of this embodiment includes a diode bridge, full-wave rectifies the AC voltage V1, and outputs the rectified voltage V2. Note that the rectifier circuit 31 may also half-wave rectify the AC voltage V1.

[0019] The switching circuit 32 has at least one switching element. The switching circuit 32 performs a switching operation of turning the switching element on and off, thereby converting the rectified voltage V2 and outputting an output voltage Vo that has been adjusted to a desired DC voltage. The output voltage Vo is applied across the lighting load 4, and a DC output current Io flows through the lighting load 4. When the output current Io flows through the lighting load 4, the lighting load 4 lights up. The switching circuit 32 adjusts the intensity of the light emitted by the lighting load 4 by controlling the magnitude of the output current Io.

[0020] The switching circuit 32 includes, for example, a boost converter and a buck converter. In this case, the boost converter has a power factor correction function and boosts the rectified voltage V2 to correct the power factor. The buck converter reduces the output voltage of the boost converter to generate the output voltage Vo.

[0021] The switching circuit 32 may also include, for example, a step-up / step-down converter. In this case, the step-up / step-down converter may be configured as a single-stage converter (SS converter). The SS converter is a one-converter converter (one-time voltage conversion) that has the functions of a power factor correction circuit and an AC / DC converter.

[0022] In the switching circuit 32 of this embodiment, the switching elements included in the switching circuit 32 switch at a switching frequency of 40 kHz or more and 500 kHz or less. Specifically, if the switching circuit 32 includes multiple switching elements, at least one of the multiple switching elements switches at a switching frequency of 40 kHz or more and 500 kHz or less. For this reason, the lighting circuit 3 is prone to generating noise whose fundamental frequency is the switching frequency. Meanwhile, lighting fixtures incorporating the lighting device 1 must satisfy noise standards applicable to lighting fixtures. Examples of noise standards include CISPR15 established by the International Special Committee on Radio Interference (CISPR) and the Electrical Appliance and Material Safety Act of Japan.

[0023] Noise standards such as CISPR15 specify the permissible values ​​of disturbance voltage (noise conducted voltage) at power terminals, load terminals, and control terminals, as well as the permissible values ​​of radiated electromagnetic interference. For example, the permissible values ​​of disturbance voltage at power terminals are specified in the frequency range of 9 kHz to 30 MHz. The permissible values ​​of disturbance voltage at load terminals and control terminals are specified in the frequency range of 150 kHz to 30 MHz. The permissible values ​​of the magnetic field component of the electromagnetic field strength of radiated electromagnetic interference are specified in the frequency range of 9 kHz to 30 MHz. The permissible values ​​of the electric field component of the electromagnetic field strength of radiated electromagnetic interference are specified in the frequency range of 30 MHz to 300 MHz. The permissible values ​​of disturbance voltage are specified in quasi-peak (QP) and average (AV) values. The permissible values ​​of radiated electromagnetic interference are specified in quasi-peak values.

[0024] Therefore, the lighting device 1 includes a filter circuit 2 to meet noise standards.

[0025] The filter circuit 2 includes a pair of input units 241 and 242 and a pair of output units 251 and 252. The pair of input units 241 and 242 have conductors such as terminals, solder, or circuit patterns on a substrate to which the pair of power supply lines W11 and W12 are electrically connected, respectively. In FIG. 1 , the input unit 241 is electrically connected to the power supply line W11, and the input unit 242 is electrically connected to the power supply line W12. The pair of output units 251 and 252 have conductors such as wires, bus bars, or circuit patterns on a substrate that are electrically connected to the input units of the lighting circuit 3.

[0026] The filter circuit 2 has a first inductor circuit 21, a second inductor circuit 22, and a capacitor circuit 23. A series circuit of the first inductor circuit 21 and the capacitor circuit 23 is electrically connected between a pair of power supply paths W11 and W12 via a pair of input parts 241 and 242. The second inductor circuit 22 is electrically connected between at least one of both ends of the capacitor circuit 23 and the lighting circuit 3.

[0027] That is, the first inductor circuit 21, the capacitor circuit 23, and the second inductor circuit 22, which are electrically connected between the pair of power supply lines W11, W12 and the lighting circuit 3, are electrically connected from the pair of power supply lines W11, W12 to the first inductor circuit 21, the capacitor circuit 23, and the second inductor circuit 22 in this order. Such a filter circuit 2 is an LCL type filter circuit.

[0028] By including the LCL type filter circuit 2, the lighting device 1 can suppress noise emitted to the outside over a wider frequency range.

[0029] (2) Filter circuit (2.1) Filter circuit configuration FIG. 2 shows a configuration of a filter circuit 2A as an example of the filter circuit 2. As shown in FIG.

[0030] The filter circuit 2A has a series circuit of a first inductor circuit 21 and a capacitor circuit 23 electrically connected between a pair of power supply paths W11, W12, and a second inductor circuit 22 electrically connected between at least one of the ends of the capacitor circuit 23 and the lighting circuit 3.

[0031] The capacitor circuit 23 of this embodiment includes a capacitor C1 that functions as an X capacitor (across-the-line capacitor) that suppresses normal-mode noise. The capacitor C1 is electrically connected between the pair of power supply lines W11 and W12 via the first inductor circuit 21.

[0032] In the filter circuit 2A, the first inductor circuit 21 includes a first common-mode noise filter Lc1 and a first normal-mode noise filter Ln1, and the second inductor circuit 22 includes a second normal-mode noise filter Ln2. A "common-mode noise filter" is a filter for suppressing common-mode noise, and a "normal-mode noise filter" is a filter for suppressing normal-mode (difference-mode) noise. In the following description, "noise filter" may be abbreviated as "NF." For example, the first common-mode noise filter Lc1 will be abbreviated as the first common-mode NFLc1, the first normal-mode noise filter Ln1 will be abbreviated as the first normal-mode NFLn1, and the second normal-mode noise filter Ln2 will be abbreviated as the second normal-mode NFLn2.

[0033] The first common mode NFLc1 includes two coils 211 and 212. One end of the coil 211 is electrically connected to the power supply line W11 via an input section 241, and one end of the coil 212 is electrically connected to the power supply line W12 via an input section 242. The other end of the coil 211 is electrically connected to one end of the capacitor C1 via a first normal mode NFLn1, and the other end of the coil 212 is electrically connected to the other end of the capacitor C1 and an output section 252. The connection point between the coil 211 and the capacitor C1 is electrically connected to the output section 251 via a second normal mode NFLn2.

[0034] The first inductor circuit 21 is preferably a hybrid choke coil in which two coils 211, 212 are wound around one iron core. In a hybrid choke coil, the two coils 211, 212 function as the first common mode NFLc1. The first inductor circuit 21 also functions as the first normal mode NFLn1 by generating leakage magnetic flux in the choke coil. That is, the first common mode NFLc1 and the first normal mode NFLn1 are configured by the choke coil. For example, the choke coil forms a closed magnetic circuit. Furthermore, by configuring the first inductor circuit 21 by a hybrid choke coil, the first common mode NFLc1 and the first normal mode NFLn1 can be configured by a single component, and the filter circuit 2 can be made smaller.

[0035] 3 shows an equivalent circuit of the first inductor circuit 21 configured with a hybrid-type choke coil. In the equivalent circuit of the first inductor circuit 21, the first normal mode NFLn1 is configured with a normal mode NFLn11 and a normal mode NFLn12. The normal mode NFLn11 is connected in series to the power feed line W11 via an input part 241. The normal mode NFLn12 is connected in series to the power feed line W12 via an input part 242.

[0036] The inductances of the first common mode NFLc1, first normal mode NFLn1, and second normal mode NFLn2 are preferably set to fall within the following ranges. Note that when the inductance of a noise filter is indicated in the following description, an "*" is added to the end of the noise filter's symbol.

[0037] The inductance Lc1* of the first common mode NFLc1 is preferably 11 to 70 mH. The inductance Ln1* of the first normal mode NFLn1 is preferably 0.2 to 3 mH. The inductance Ln2* of the second normal mode NFLn2 is preferably 0.2 to 3 mH.

[0038] In particular, the inductance Ln1* of the first normal mode NFLn1 is preferably 0.2 to 2 mH, and the inductance Ln2* of the second normal mode NFLn2 is preferably 0.33 to 0.82 mH.

[0039] Furthermore, it is preferable that the inductance Lc1* of the first common mode NFLc1 be greater than the sum of the inductance Ln1* of the first normal mode NFLn1 and the inductance Ln2* of the second normal mode NFLn2. That is, Lc1* > Ln1* + Ln2*. In this case, the filter circuit 2 can sufficiently suppress both common mode noise and normal mode noise.

[0040] Furthermore, it is preferable that the inductance Ln1* of the first normal mode NFLn1 and the inductance Ln2* of the second normal mode NFLn2 are equal. That is, Ln1*=Ln2*. In this case, the first normal mode NFLn1 and the second normal mode NFLn2 can be made of the same components, allowing the components constituting the filter circuit 2 to be standardized.

[0041] As described above, the filter circuit 2A includes a hybrid choke coil serving as the first inductor circuit 21, which has the functions of the first common mode NFLc1 and the first normal mode NFLn1. Furthermore, the filter circuit 2A includes a second normal mode NFLn2 serving as the second inductor circuit 22. Furthermore, the filter circuit 2A includes a capacitor C1 functioning as an X capacitor between the first inductor circuit 21 and the second inductor circuit 22. The filter circuit 2A having such a configuration can suppress noise emitted to the outside over a wider frequency range. In particular, the filter circuit 2A can suppress noise even in a relatively low frequency range of about 9 kHz to several hundred kHz.

[0042] (2.2) Comparison FIG. 4 shows the configuration of the filter circuit 8 of the comparative example.

[0043] The filter circuit 8 includes a capacitor 81, a common mode NF82, a normal mode NF83, a pair of input ports 841 and 842, and a pair of output ports 851 and 852. The pair of input ports 841 and 842 are electrically connected to a pair of power supply paths W11 and W12, respectively. The pair of output ports 851 and 852 are electrically connected to the input ports of the lighting circuit 3.

[0044] The capacitor 81 is electrically connected between the pair of input ports 841 and 842. That is, the capacitor 81 is electrically connected between the pair of power supply lines W11 and W12. The common mode NF82 is electrically connected in series to the pair of power supply lines W11 and W12 via the pair of input ports 841 and 842. One end of the normal mode NF83 is electrically connected to the input port 841 via the common mode NF82. The other end of the normal mode NF83 is electrically connected to the output port 851. The input port 842 is electrically connected to the output port 852 via the common mode NF82.

[0045] That is, the capacitor 81, common mode NF82, and normal mode NF83 are electrically connected between the pair of power feed lines W11, W12 and the lighting circuit 3, and are electrically connected from the pair of power feed lines W11, W12 to the capacitor 81, common mode NF82, and normal mode NF83 in this order. Such a filter circuit 8 is a CLL type filter circuit.

[0046] The noise suppression effects of the filter circuit 2A of this embodiment and the filter circuit 8 of the comparative example will be described below with reference to the frequency characteristic diagrams of FIGS. 5 to 8. FIGS. 5 to 8 show the peak values ​​of the interference voltage measured at the power terminals of the lighting device as measured values ​​Y11, Y1, Y12, and Y2, respectively. In FIGS. 5 to 8, Ya indicates the QP standard value (quasi-peak standard value) of the interference voltage at the power terminals specified in CISPR J15:2017. In FIGS. 5 to 8, Yb indicates the AV standard value (average standard value) of the interference voltage at the power terminals specified in CISPR J15:2017. The noise suppression effect of the filter circuit 2A of this embodiment is an effect obtained by using a lighting device 1 including the filter circuit 2A. The noise suppression effect of the filter circuit 8 of the comparative example is an effect obtained by replacing the filter circuit 2A of the lighting device 1 with the filter circuit 8.

[0047] 5 and 6 show the frequency characteristics of interference voltage measured on a 30W-class lighting fixture. In the 30W-class lighting fixture, the switching circuit 32 includes a boost converter and a buck converter. At least one of the switching frequencies of the switching elements of the boost converter and the buck converter is 40 kHz or higher and 500 kHz or lower. In the following description, the switching frequency of the switching element of the switching circuit 32 may be referred to as the switching frequency of the switching circuit 32.

[0048] 5 shows the measured value Y11 of the interference voltage by the filter circuit 8 of the comparative example, together with the QP standard value Ya and the AV standard value Yb of the interference voltage. When the filter circuit 8 is used in a 30 W class lighting fixture, the measured value Y11 peaks around 40 to 60 kHz, around 100 kHz, and around 150 kHz. Therefore, when the filter circuit 8 is used in a 30 W class lighting fixture, the interference voltage at the power terminal may not satisfy the QP standard value Ya or the AV standard value Yb around 40 to 60 kHz, around 100 kHz, and around 150 kHz.

[0049] FIG. 6 shows the measured value Y1 of the interference voltage measured by the filter circuit 2A of this embodiment, along with the QP standard value Ya and the AV standard value Yb of the interference voltage. When the filter circuit 2A is used in a 30W-class lighting fixture, the measured value Y1 is smaller than the measured value Y11 in the range of 40 to 500 kHz. Therefore, the filter circuit 2A can reduce noise corresponding to the switching frequency of the switching circuit 32 (40 kHz or more and 500 kHz or less) more effectively than the filter circuit 8. In particular, the measured value Y1 significantly reduces the interference voltage in the range of 40 to 150 kHz compared to the measured value Y11, suppressing peaks near 40 to 60 kHz, 100 kHz, and 150 kHz. For example, the peaks near 40 to 60 kHz are approximately 16 dB lower in the measured value Y1 than in the measured value Y11.

[0050] 7 shows the measured value Y12 of the interference voltage by the filter circuit 8 of the comparative example, along with the QP standard value Ya and the AV standard value Yb of the interference voltage. The measured value Y12 when the filter circuit 8 is used in a 10W class lighting fixture has peaks around 60kHz, 110kHz, and 150kHz. Therefore, when the filter circuit 8 is used in a 10W class lighting fixture, the interference voltage at the power terminal may not satisfy the QP standard value Ya or the AV standard value Yb around 60kHz, 110kHz, and 150kHz.

[0051] FIG. 8 shows the measured value Y2 of the interference voltage obtained by the filter circuit 2A of this embodiment, along with the QP standard value Ya and the AV standard value Yb of the interference voltage. The measured value Y2 when the filter circuit 2A is used in a 10 W-class lighting fixture is smaller than the measured value Y12 in the range of 40 to 500 kHz. Therefore, the filter circuit 2A can reduce noise corresponding to the switching frequency of the switching circuit 32 (40 kHz or more and 500 kHz or less) more effectively than the filter circuit 8. In particular, the measured value Y2 suppresses peaks near 60 kHz, 110 kHz, and 150 kHz more effectively than the measured value Y12. For example, the peaks near 40 to 60 kHz are approximately 16 dB lower in the measured value Y2 than in the measured value Y12.

[0052] (3) Modification of the first inductor 9 and 10 show filter circuits 2B and 2C as modifications of the filter circuit 2, respectively.

[0053] 9 includes only the first normal mode NFLn1 out of the first common mode NFLc1 and the first normal mode NFLn1. In this case, the first inductor circuit 21 serves as a filter for suppressing normal mode noise.

[0054] 10 includes only the first common mode NFLc1 of the first common mode NFLc1 and the first normal mode NFLn1. In this case, the first inductor circuit 21 serves as a filter for suppressing common mode noise.

[0055] Furthermore, even if the filter circuit 2 is configured with the filter circuit 2B or 2C, the lighting device 1 can suppress noise emitted to the outside over a wider frequency range by including the LCL type filter circuit 2.

[0056] (4) Modification of the second inductor 11 and 12 show filter circuits 2D and 2E as modifications of the filter circuit 2, respectively.

[0057] The second inductor circuit 22 of the filter circuit 2D of FIG. 11 further includes a second common mode NFLc2 in addition to the second normal mode NFLn2.

[0058] The second common mode NFLc2 includes two coils 221 and 222. One end of the coil 221 is electrically connected to one end of the capacitor C1 via the second normal mode NFLn2, and one end of the coil 222 is electrically connected to the other end of the capacitor C1. The other end of the coil 221 is electrically connected to the output section 251, and the other end of the coil 222 is electrically connected to the output section 252. In this case, the second inductor circuit 22 functions as a filter for suppressing normal mode noise and common mode noise.

[0059] In FIG. 11, the second inductor circuit 22 is preferably a hybrid choke coil in which two coils 221, 222 are wound around one iron core. In a hybrid choke coil, the two coils 221, 222 function as the second common mode NFLc2. The second inductor circuit 22 also functions as the second normal mode NFLn2 by generating leakage magnetic flux in the choke coil. That is, the second common mode NFLc2 and the second normal mode NFLn2 are configured by a choke coil. For example, the choke coil forms a closed magnetic circuit. Furthermore, by configuring the second inductor circuit 22 by a hybrid choke coil, the second common mode NFLc2 and the second normal mode NFLn2 can be configured by a single component, and the filter circuit 2 can be made smaller.

[0060] 12 includes only the second common mode NFLc2 of the second common mode NFLc2 and the second normal mode NFLn2. In this case, the second inductor circuit 22 serves as a filter for suppressing common mode noise.

[0061] Furthermore, even if the filter circuit 2 is configured with the filter circuit 2D or 2E, the lighting device 1 can suppress noise emitted to the outside over a wider frequency range by including the LCL type filter circuit 2.

[0062] (5) Modified capacitor FIG. 13 shows a filter circuit 2F as a modification of the filter circuit 2. In FIG.

[0063] 13 includes capacitors C11 to C13 that function as Y capacitors (line bypass capacitors) that suppress common-mode noise. A series circuit of capacitors C11 and C12 is connected between the output terminals of first inductor circuit 21 (between the input terminals of second inductor circuit 22). Capacitor C13 is connected between the connection point of capacitors C11 and C12 and circuit ground.

[0064] Furthermore, even if the filter circuit 2 is configured as the filter circuit 2F, the lighting device 1 is provided with an LCL type filter circuit 2, thereby being able to suppress noise emitted to the outside over a wider frequency range.

[0065] 2, 9, 10, 11, and 12, a Y capacitor (capacitors C11 to C13) may be connected in parallel with the capacitor C1. In this case, the lighting device 1 also includes an LCL-type filter circuit 2, which can suppress noise emitted to the outside over a wider frequency range.

[0066] (6) Modified lighting circuit FIG. 14 shows a modified example of the lighting circuit 3.

[0067] 14 further includes a capacitor 33 in addition to the rectifier circuit 31 and the switching circuit 32. The capacitor 33 is connected between the output terminals of the rectifier circuit 31 (between the input terminals of the switching circuit 32) and receives a rectified voltage V2. The capacitor 33 functions as an X capacitor that suppresses normal mode noise.

[0068] In this modification, the lighting circuit 3 includes the capacitor 33 as an X capacitor, thereby making it possible to further suppress normal mode noise. That is, the lighting device 1 can further suppress noise emitted to the outside.

[0069] (7) Modified filter circuit The lighting device 1 may include a filter circuit 2G and a rectifier circuit 31A shown in Fig. 15. The filter circuit 2G includes a first inductor circuit 21, a capacitor circuit 23, and a second inductor circuit 22. The specific configurations of the first inductor circuit 21, the second inductor circuit 22, and the capacitor circuit 23 of the filter circuit 2G may be any of the configurations in the above-described embodiment and modified examples.

[0070] The rectifier circuit 31A is electrically connected between the capacitor circuit 23 and the second inductor circuit 22 of the filter circuit 2G. The rectifier circuit 31A includes at least one rectifier element (such as a diode, a thyristor, or a triac) and rectifies the AC voltage V11 input from the pair of power supply lines W11 and W12 via the first inductor circuit 21 and the capacitor circuit 23 of the filter circuit 2G. The rectifier circuit 31A of this embodiment includes a diode bridge, full-wave rectifies the AC voltage V11, and outputs a rectified voltage V21. The rectified voltage V21 is input to the switching circuit 32 via the second inductor circuit 22. The rectifier circuit 31A may also be configured to half-wave rectify the AC voltage V11.

[0071] In the filter circuit 2G of this modification, the second inductor circuit 22 is provided on the output side of the rectifier circuit 31A. Therefore, the insulation distance required for the second inductor circuit 22 can be shortened compared to when the second inductor circuit 22 is provided on the input side of the rectifier circuit 31A. As a result, the second inductor circuit 22 can be made smaller, and the range of components that can be used to configure the second inductor circuit 22 is expanded.

[0072] 16, the lighting device 1 may further include a capacitor 33A. The capacitor 33A is connected between the output terminals of the second inductor circuit 22 (between the input terminals of the switching circuit 32), and is applied with the rectified voltage V21 via the second inductor circuit 22. The capacitor 33A functions as an X capacitor that suppresses normal mode noise. In this modification, by including the capacitor 33A as the X capacitor, normal mode noise can be further suppressed. In other words, the lighting device 1 can further suppress noise emitted to the outside.

[0073] The lighting device 1 may further include an electric element K1, as shown in FIG. 17. The electric element K1 in FIG. 17 is connected in series to one of a pair of electrical paths electrically connecting the rectifier circuit 31A and the second inductor circuit 22. The electric element K1 is an element whose impedance does not change with frequency, such as a resistor, diode, contact, or fuse. Note that "the impedance does not change with frequency" includes cases where the impedance of the electric element K1 changes with frequency within a range in which the electrical characteristics of the electric element K1 are considered to be the same. Note that the electric element K1 may be connected to one or both of the pair of electrical paths electrically connecting the rectifier circuit 31A and the second inductor circuit 22, and may be connected in series or in parallel with each electrical path. The lighting device 1 may also include multiple electric elements K1.

[0074] (8) Lighting equipment 18 shows a lighting fixture 5A that is directly attached to a ceiling. The lighting fixture 5A includes a light source unit 100 and a housing 511. The housing 511 is directly attached to the ceiling and supports the light source unit 100. The light source unit 100 includes a lighting device 1 and a lighting load 4, and is detachably attached to the housing 511. However, the housing 511 may be embedded in the ceiling, or may be directly attached to a wall or embedded in the wall.

[0075] FIG. 19A shows lighting fixture 5B, which is a downlight recessed in ceiling panel 6. Lighting fixture 5B includes lighting device 1, lighting load 4, and housings 521 and 522. Housing 521 is made of metal such as aluminum and has a cylindrical shape with a closed top and an open bottom. Housing 521 supports lighting load 4, and lighting load 4 is attached to the top surface of housing 521. Lighting load 4 is a plurality of LEDs mounted on a board. The opening on the bottom of housing 521 is closed with a disk-shaped cover 523. Cover 523 is made of a translucent material such as glass or polycarbonate. Lighting device 1 is housed in and supported by metal housing 522, which is formed in a rectangular box shape, and is disposed on the top surface of ceiling panel 6. Lighting device 1 is electrically connected to lighting load 4 via electric cable 524 and connector 525.

[0076] FIG. 19B shows lighting fixture 5C, another downlight recessed in ceiling panel 6. Lighting fixture 5C includes lighting device 1, lighting load 4, and housing 531. Housing 531 is made of metal such as aluminum and has a cylindrical shape with a closed top and an open bottom. The opening at the bottom of housing 531 is closed by disk-shaped cover 532. Cover 532 is made of a translucent material such as glass or polycarbonate. Housing 531 is divided into upper and lower compartments by disk-shaped partition plate 533. Lighting device 1 is disposed on the upper side of partition plate 533, and housing 531 supports lighting device 1. Lighting load 4 is disposed on the lower side of partition plate 533. Lighting device 1 is electrically connected to lighting load 4 by electric cable 535 passing through wire hole 534 in partition plate 533.

[0077] Note that the lighting fixture including the lighting device 1 and the lighting load 4 is not limited to lighting fixture 5A in Fig. 18, lighting fixture 5B in Fig. 19A, and lighting fixture 5C in Fig. 19B, and may be other lighting fixtures such as a spotlight, a signal light, digital signage, etc. Furthermore, the lighting fixture may be used either indoors or outdoors.

[0078] (9) Summary A lighting device (1) according to a first aspect of the embodiment includes a filter circuit (2) and a lighting circuit (3). The filter circuit (2) is electrically connected to a pair of power supply lines (W11, W12) that supply AC power. The lighting circuit (3) receives AC power from the pair of power supply lines (W11, W12) via the filter circuit (2) and supplies lighting power to a lighting load (4). The filter circuit (2) includes a series circuit of a first inductor circuit (21) and a capacitor circuit (23) that are electrically connected between the pair of power supply lines (W11, W12), and a second inductor circuit (22) that is electrically connected between at least one of the ends of the capacitor circuit (23) and the lighting circuit (3).

[0079] The lighting device (1) described above can suppress noise emitted to the outside over a wider frequency range.

[0080] In the lighting device (1) of the second aspect of the embodiment, in the first aspect, the first inductor circuit (21) preferably includes a series circuit of a common mode noise filter (Lc1) and a normal mode noise filter (Ln1).

[0081] The lighting device (1) described above can suppress common mode and normal mode noises emitted to the outside over a wider frequency range.

[0082] In the lighting device (1) of the third aspect of the embodiment, in the second aspect, it is preferable that the inductance (Lc1*) of the common mode noise filter (Lc1) is greater than the sum of the inductance (Ln1*) of the normal mode noise filter (Ln1) and the inductance (Ln2*) of the second inductor circuit (22).

[0083] The above-described lighting device (1) can sufficiently suppress both common mode noise and normal mode noise.

[0084] In the lighting device (1) of the fourth aspect of the embodiment, in the second or third aspect, it is preferable that the inductance (Ln1*) of the normal mode noise filter (Ln1) and the inductance (Ln2*) of the second inductor circuit (22) are equal.

[0085] The lighting device (1) described above can standardize the components that make up the filter circuit (2).

[0086] In the lighting device (1) of the fifth aspect according to the embodiment, in any one of the second to fourth aspects, the common mode noise filter (Lc1) and the normal mode noise filter (Ln1) are preferably configured by choke coils.

[0087] In the lighting device (1) described above, the common mode noise filter (Lc1) and the normal mode noise filter (Ln1) can be configured as one component, and the filter circuit (2) can be made smaller.

[0088] In the lighting device (1) of the sixth aspect according to the present embodiment, in the first aspect, the first inductor circuit (21) preferably includes a normal mode noise filter (Ln1).

[0089] The lighting device (1) described above can suppress normal mode noise emitted to the outside over a wider frequency range.

[0090] In the lighting device (1) of the seventh aspect according to the present embodiment, in the first aspect, the first inductor circuit (21) preferably includes a common mode noise filter (Lc1).

[0091] The lighting device (1) described above can suppress common mode noise emitted to the outside over a wider frequency range.

[0092] In the lighting device (1) of the eighth aspect of the embodiment, in any one of the first to seventh aspects, the second inductor circuit (22) preferably includes a series circuit of a common mode noise filter (Lc2) and a normal mode noise filter (Ln2).

[0093] The lighting device (1) described above can suppress common mode and normal mode noises emitted to the outside over a wider frequency range.

[0094] In the lighting device (1) of the ninth aspect according to the embodiment, in the eighth aspect, the common mode noise filter (Lc2) and the normal mode noise filter (Ln2) included in the second inductor circuit (22) are preferably configured by choke coils.

[0095] In the lighting device (1) described above, the common mode noise filter (Lc2) and the normal mode noise filter (Ln2) of the second inductor circuit (22) can be configured as a single component, thereby enabling the filter circuit (2) to be miniaturized.

[0096] In the lighting device (1) of the tenth aspect of the present invention, in any one of the first to seventh aspects, the second inductor circuit (22) preferably includes a normal mode noise filter (Ln2).

[0097] The lighting device (1) described above can suppress normal mode noise emitted to the outside over a wider frequency range.

[0098] In the lighting device (1) of an eleventh aspect according to the present invention, in any one of the first to seventh aspects, the second inductor circuit (22) preferably includes a common mode noise filter (Lc2).

[0099] The lighting device (1) described above can suppress common mode noise emitted to the outside over a wider frequency range.

[0100] In the lighting device (1) according to a twelfth aspect of the present embodiment, in any one of the first to eleventh aspects, the lighting circuit (3) preferably includes a rectifier circuit (31) and a capacitor (33). The rectifier circuit (31) rectifies an AC voltage (V1) input from a pair of power supply lines (W11, W12) via a filter circuit (2). The capacitor (33) is connected between output terminals of the rectifier circuit (31).

[0101] The lighting device (1) described above can further suppress noise emitted to the outside.

[0102] In the lighting device (1) of the thirteenth aspect of the embodiment, in any one of the first to eleventh aspects, it is preferable that the lighting device (1) further includes a rectifier circuit (31A) electrically connected between the capacitor circuit (23) and the second inductor circuit (22).

[0103] The lighting device (1) described above can shorten the insulation distance required for the second inductor circuit (22).

[0104] Preferably, the lighting device (1) of the fourteenth aspect according to the present invention is the thirteenth aspect, further including a capacitor (33A) connected between output terminals of the rectifier circuit (31A).

[0105] The lighting device (1) described above can further suppress noise emitted to the outside.

[0106] In the lighting device (1) of the fifteenth aspect of the embodiment, in the thirteenth or fourteenth aspect, it is preferable that the lighting device (1) further includes an electric element (K1) electrically connected between the rectifier circuit (31A) and the second inductor circuit (22), and that the impedance of the electric element (K1) does not change depending on the frequency.

[0107] Even though the lighting device (1) described above includes the electric element (K1), the insulation distance required for the second inductor circuit (22) can be shortened.

[0108] In the lighting device (1) of the 16th aspect of the embodiment, in any one of the 1st to 15th aspects, the lighting circuit (3) has a switching circuit (32), and it is preferable that the switching frequency of the switching circuit (32) is 40 kHz or more and 500 kHz or less.

[0109] The lighting device (1) described above can reduce noise corresponding to the switching frequency of the switching circuit (32).

[0110] A lighting fixture (5A, 5B, 5C) according to a seventeenth aspect of the present embodiment includes a lighting device (1) according to any one of the first to sixteenth aspects, and a housing (511, 521, 522, 531) that supports the lighting device (1).

[0111] The above-described lighting fixtures (5A, 5B, 5C) can suppress noise emitted to the outside over a wider frequency range. [Explanation of symbols]

[0112] 1 lighting device 2(2A~2G) Filter circuit 21 First inductor circuit 22 Second inductor circuit 23 Capacitor Circuit 3 Lighting circuit 31, 31A rectifier circuit 32 Switching Circuit 33, 33A capacitor 4 Lighting load 5A, 5B, 5C lighting fixtures 511, 521, 522, 531 housing Lc1 First common mode noise filter (common mode noise filter) Lc2 Second common mode noise filter (common mode noise filter) Ln1 1st normal mode noise filter (normal mode noise filter) Ln2 Second normal mode noise filter (normal mode noise filter) Lc1*, Ln1*, Ln2* inductance W11, W12 power supply line K1 Electrical element

Claims

1. a filter circuit electrically connected to a pair of power supply paths that supply AC power; a lighting circuit that receives the AC power from the pair of power supply paths via the filter circuit and supplies lighting power to a lighting load, The filter circuit comprises: a series circuit including a first inductor circuit and a capacitor circuit electrically connected between the pair of power supply paths; a second inductor circuit electrically connected between at least one of the ends of the capacitor circuit and the lighting circuit, the lighting circuit includes a rectifier circuit that rectifies an AC voltage input from the pair of power supply paths via a part of the filter circuit, the first inductor circuit, the capacitor circuit, the rectifier circuit, and the second inductor circuit are electrically connected in this order from the pair of power supply paths, the second inductor circuit includes a second normal mode noise filter; The first inductor circuit comprises: a first normal mode noise filter including a coil; a first common mode noise filter including a coil; The coil of the first common mode noise filter and the coil of the first normal mode noise filter are not connected to a capacitor but are electrically connected to the pair of power supply paths. Lighting device.

2. The first inductor circuit includes a series circuit of the first common mode noise filter and the first normal mode noise filter. The lighting device of claim 1.

3. The inductance of the first common mode noise filter is greater than the sum of the inductance of the first normal mode noise filter and the inductance of the second inductor circuit. The lighting device of claim 2.

4. The inductance of the first normal mode noise filter is equal to the inductance of the second inductor circuit. The lighting device according to claim 2 or 3.

5. The first common mode noise filter and the first normal mode noise filter are each formed of a choke coil.

5. The lighting device according to claim 2.

6. The second inductor circuit comprises a series circuit of a second common mode noise filter and the second normal mode noise filter.

6. The lighting device according to claim 1.

7. The second common mode noise filter and the second normal mode noise filter provided in the second inductor circuit are configured with a choke coil. The lighting device of claim 6.

8. The second inductor circuit includes a second common mode noise filter.

6. The lighting device according to claim 1.

9. The lighting circuit includes a capacitor connected between output terminals of the rectifier circuit.

9. The lighting device according to claim 1.

10. The method of claim 1, further comprising: providing an electrical element electrically connected between the rectifier circuit and the second inductor circuit; The impedance of the electrical element does not change with frequency 10. The lighting device according to any one of claims 1 to 9.

11. The lighting circuit has a switching circuit, The switching frequency of the switching circuit is 40 kHz or more and 500 kHz or less.

11. The lighting device according to any one of claims 1 to 10.

12. A lighting device according to any one of claims 1 to 11; a housing for supporting the lighting device; Lighting fixtures.

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