Lighting devices and lighting fixtures

Abstract

To provide a lighting device capable of suppressing noise emitted to the external over a wide frequency range, and a lighting apparatus having the same.SOLUTION: A lighting device 1 includes a filter circuit 2 and a lighting circuit 3. The filter circuit 2 is electrically connected to a pair of power feeding lines W11, W12 for supplying AC power. The lighting circuit 3 is supplied with AC power from the pair of power feeding lines W11, W12 through the filter circuit 2, and supplies lighting power to an illumination load 4. The filter circuit 2 includes a series circuit of a first inductor circuit 21 and a capacitor circuit 23 which are electrically connected between the pair of power feeding lines W11, W12, and a second inductor circuit 22 which is electrically connected to at least one of both ends of the capacitor circuit 23 and the lighting circuit 3.SELECTED DRAWING: Figure 1

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 an 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 of the choke coil and the output capacitor, and the midpoint of 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] JP 2018-152233 A Summary of the Invention [Problem to be solved by the invention]

[0005] Lighting fixtures equipped with a lighting device such as that described in Patent Document 1 are required to meet noise standards. However, noise standards tend to be revised year by year to become stricter, 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 noise standard can be satisfied when the lighting device is 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 same. [Means for solving the problem]

[0008] A lighting device according to an 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 are 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 first inductor circuit includes a series circuit of a first common mode noise filter and a first normal mode noise filter. The second inductor circuit includes: Second Common mode noise filter and Second It is equipped with a series circuit with a normal mode noise filter.

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

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

[0011] [Figure 1] FIG. 1 is a block diagram showing a lighting device according to an embodiment. [Diagram 2] FIG. 2 is a circuit diagram showing a filter circuit of the lighting device. [Diagram 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. [Diagram 5]FIG. 5 is a diagram showing frequency characteristics of interference 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 above. [Figure 7] FIG. 7 is a diagram showing frequency characteristics of disturbance 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 above. [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 a 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 PREFERRED EMBODIMENTS

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

[0013] The lighting device and the lighting fixture according to the embodiment will be described in detail below with reference to the drawings. However, each figure described in the following embodiment is a schematic diagram, and the size and thickness ratio of each component do not necessarily reflect the actual dimensional ratio. Note that the configuration described in the following embodiment is merely an example of the present disclosure. The present disclosure is not limited to the following embodiment, 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, W12 into DC power and supplies the DC power to a lighting load 4. The lighting load 4 is illuminated 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. 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) or semiconductor laser diodes (Laser Diodes, LD). 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 connection relationship that combines 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, W12 via a filter circuit 2, to supply lighting power to the lighting load 4. The pair of power supply lines W11, W12 include conductors such as electric wires, bus bars, or circuit patterns on a 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 a pair of power supply lines W11, 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. 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 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 is turned on. 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 steps down the output voltage of the boost converter to generate the output voltage Vo.

[0021] Furthermore, the switching circuit 32 may 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 type (one-time voltage conversion) converter that has a function of a power factor correction circuit and a function of an AC / DC converter.

[0022] In the switching circuit 32 of this embodiment, the switching element included in the switching circuit 32 switches at a switching frequency of 40 kHz or more and 500 kHz or less. In particular, 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 likely to generate noise having the switching frequency as a fundamental frequency. Meanwhile, a lighting fixture incorporating the lighting device 1 needs to satisfy noise standards applied 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 the disturbance voltage (noise terminal voltage) at the power terminal, the load terminal, and the control terminal, as well as the permissible values ​​of the radiated electromagnetic interference. For example, the permissible values ​​of the disturbance voltage at the power terminal are specified in the frequency range of 9 kHz to 30 MHz. The permissible values ​​of the disturbance voltage at the load terminal and the control terminal 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 the 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 the radiated electromagnetic interference are specified in the frequency range of 30 MHz to 300 MHz. The permissible values ​​of the disturbance voltage are specified in quasi-peak (QP) and average (AV). The permissible values ​​of the radiated electromagnetic interference are specified in quasi-peak.

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

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

[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, W12 via a pair of input parts 241, 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 paths W11, W12 and the lighting circuit 3, are electrically connected from the pair of power supply paths W11, W12 to the first inductor circuit 21, the capacitor circuit 23, and the second inductor circuit 22 in that order. Such a filter circuit 2 is an LCL type filter circuit.

[0028] The lighting device 1 includes the LCL type filter circuit 2, and is therefore able to 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) for suppressing 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, the "noise filter" may be abbreviated as "NF." For example, the first common mode noise filter Lc1 is abbreviated as the first common mode NFLc1, the first normal mode noise filter Ln1 is abbreviated as the first normal mode NFLn1, and the second normal mode noise filter Ln2 is 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 the input unit 241, and one end of the coil 212 is electrically connected to the power supply line W12 via the input unit 242. The other end of the coil 211 is electrically connected to one end of the capacitor C1 via the first normal mode NFLn1, and the other end of the coil 212 is electrically connected to the other end of the capacitor C1 and the output unit 252. The connection point between the coil 211 and the capacitor C1 is electrically connected to the output unit 251 via the 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 the 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 flux in the choke coil. That is, the first common mode NFLc1 and the first normal mode NFLn1 are configured with a choke coil. For example, the choke coil configures a closed magnetic circuit. By configuring the first inductor circuit 21 with a hybrid choke coil, the first common mode NFLc1 and the first normal mode NFLn1 can be configured with one 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 supply line W11 via an input part 241. The normal mode NFLn12 is connected in series to the power supply 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. In the following description, when the inductance of a noise filter is indicated, an asterisk (*) 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] Moreover, it is preferable that the inductance Lc1* of the first common mode NFLc1 is larger 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] Moreover, 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, and the components constituting the filter circuit 2 can be standardized.

[0041] As described above, the filter circuit 2A includes a hybrid-type choke coil having the functions of the first common mode NFLc1 and the first normal mode NFLn1 as the first inductor circuit 21. Furthermore, the filter circuit 2A includes a second normal mode NFLn2 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 hundreds of kHz.

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

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

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

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

[0046] Hereinafter, the noise suppression effect by the filter circuit 2A of this embodiment and the filter circuit 8 of the comparative example will be described with reference to the frequency characteristic diagrams of FIG. 5 to FIG. 8. In FIG. 5 to FIG. 8, the peak values ​​of the interference voltage measured at the power terminal of the lighting device are shown as measured values ​​Y11, Y1, Y12, and Y2, respectively. In FIG. 5 to FIG. 8, Ya indicates the QP standard value (quasi-peak standard value) of the interference voltage at the power terminal specified in CISPRJ15:2017. In FIG. 5 to FIG. 8, Yb indicates the AV standard value (average standard value) of the interference voltage at the power terminal specified in CISPRJ15:2017. The noise suppression effect by the filter circuit 2A of this embodiment is an effect obtained by using the lighting device 1 having the filter circuit 2A. In addition, the noise suppression effect by 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 frequency characteristics of interference voltage measured on a 30W class lighting fixture. In the 30W class lighting fixture, the switching circuit 32 includes a step-up converter and a step-down converter. At least one of the switching frequency of the switching element included in the step-up converter and the switching frequency of the switching element included in the step-down converter is 40 kHz or more and 500 kHz or less. In the following description, the switching frequency of the switching element included in 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. The measured value Y11 when the filter circuit 8 is used in a 30W class lighting fixture has peaks at around 40 to 60kHz, around 100kHz, and around 150kHz. Therefore, when the filter circuit 8 is used in a 30W class lighting fixture, the interference voltage at the power terminal may not satisfy the QP standard value Ya or the AV standard value Yb at around 40 to 60kHz, around 100kHz, and around 150kHz.

[0049] FIG. 6 shows the measured value Y1 of the interference voltage by the filter circuit 2A of this embodiment together with the QP standard value Ya and the AV standard value Yb of the interference voltage. The measured value Y1 when the filter circuit 2A is used in a 30W class lighting fixture 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 (40 kHz or more and 500 kHz or less) of the switching circuit 32 compared to 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, and each peak in the range of 40 to 60 kHz, 100 kHz, and 150 kHz is suppressed. For example, the measured value Y1 has a peak in the range of 40 to 60 kHz lower by about 16 dB compared to the measured value Y11.

[0050] 7 shows the measured value Y12 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. The measured value Y12 when the filter circuit 8 is used in a 10W class lighting fixture has peaks at 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 at around 60kHz, 110kHz, and 150kHz.

[0051] FIG. 8 shows the measured value Y2 of the interference voltage by the filter circuit 2A of this embodiment, together 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 10W 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 (40 kHz or more and 500 kHz or less) of the switching circuit 32, compared to the filter circuit 8. In particular, the measured value Y2 has peaks near 60 kHz, near 110 kHz, and near 150 kHz suppressed, compared to the measured value Y12. For example, the measured value Y2 has peaks near 40 to 60 kHz lower by about 16 dB, compared to the measured value Y12.

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

[0053] 9 includes only the first normal mode NFLn1 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] The first inductor circuit 21 of the filter circuit 2C in Fig. 10 has 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 is provided with the LCL type filter circuit 2, thereby being able to suppress noise emitted to the outside over a wider frequency range.

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

[0057] The second inductor circuit 22 of the filter circuit 2D in 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 serves 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 and 222 are wound around one iron core. In the hybrid choke coil, the two coils 221 and 222 function as the second common mode NFLc2. The second inductor circuit 22 also functions as the second normal mode NFLn2 by generating leakage flux in the choke coil. That is, the second common mode NFLc2 and the second normal mode NFLn2 are configured with a choke coil. For example, the choke coil configures a closed magnetic circuit. By configuring the second inductor circuit 22 with a hybrid choke coil, the second common mode NFLc2 and the second normal mode NFLn2 can be configured with one 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 is provided with the LCL type filter circuit 2, thereby being able to suppress noise emitted to the outside over a wider frequency range.

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

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

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

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

[0066] (6) Modifications of the 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 a rectified voltage V2 is applied to the capacitor 33. 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, so that the normal mode noise can be further suppressed. That is, the lighting device 1 can further suppress the noise emitted to the outside.

[0069] (7) Modifications of the 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 of the above-mentioned embodiment and each of the 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 a 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 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 constitute the second inductor circuit 22 can be selected more widely.

[0072] 16, the lighting device 1 may further include a capacitor 33A. The capacitor 33A is connected between the output ends of the second inductor circuit 22 (between the input ends of the switching circuit 32), and the rectified voltage V21 is applied to the capacitor 33A via the second inductor circuit 22. The capacitor 33A functions as an X capacitor that suppresses normal mode noise. In this modification, by providing the capacitor 33A as an 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] Also, as shown in FIG. 17, the lighting device 1 may further include an electric element K1. The electric element K1 in FIG. 17 is connected in series to one of a pair of electric paths that electrically connect the rectifier circuit 31A and the second inductor circuit 22. The electric element K1 is an element whose impedance does not change according to frequency, such as a resistor, a diode, a contact, and a fuse. Note that "the impedance does not change according to frequency" includes the impedance changing according to frequency within a range in which the electrical characteristics of the electric element K1 can be regarded as being the same. Note that the electric element K1 may be connected to one or both of the pair of electric paths that electrically connect the rectifier circuit 31A and the second inductor circuit 22, and may be connected in series or in parallel to each electric path. Also, the lighting device 1 may include a plurality of 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 a lighting fixture 5B, which is a downlight embedded in a ceiling panel 6. The lighting fixture 5B includes a lighting device 1, a lighting load 4, and housings 521 and 522. The housing 521 is formed of a metal such as aluminum in a cylindrical shape with a closed top and an open bottom. The housing 521 supports the lighting load 4, and the lighting load 4 is attached to the upper bottom surface of the housing 521. The lighting load 4 is a plurality of LEDs mounted on a board. The lower opening of the housing 521 is closed by a disk-shaped cover 523. The cover 523 is made of a light-transmitting material such as glass or polycarbonate. The lighting device 1 is stored in a metallic housing 522 formed in a rectangular box shape, supported by the housing 522, and disposed on the upper surface of the ceiling panel 6. The lighting device 1 is electrically connected to the lighting load 4 via an electric cable 524 and a connector 525.

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

[0077] Note that the lighting fixture including the lighting device 1 and the lighting load 4 is not limited to the lighting fixture 5A in Fig. 18, the lighting fixture 5B in Fig. 19A, and the lighting fixture 5C in Fig. 19B, and may be other lighting fixtures such as a spotlight, a display 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 both ends of the capacitor circuit (23) and the lighting circuit (3).

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

[0080] In the lighting device (1) of the second aspect according to 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 above-described lighting device (1) 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 to each other.

[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, it is preferable that the common mode noise filter (Lc1) and the normal mode noise filter (Ln1) are formed of a choke coil.

[0087] In the above-described lighting device (1), 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 compact.

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

[0089] The above-described lighting device (1) 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 embodiment, in the first aspect, the first inductor circuit (21) preferably includes a common mode noise filter (Lc1).

[0091] The above-described lighting device (1) 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, it is preferable that the second inductor circuit (22) includes a series circuit of a common mode noise filter (Lc2) and a normal mode noise filter (Ln2).

[0093] The above-described lighting device (1) 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 with choke coils.

[0095] In the above-described lighting device (1), the common mode noise filter (Lc2) and the normal mode noise filter (Ln2) of the second inductor circuit (22) can be configured as one component, and the filter circuit (2) can be made compact.

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

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

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

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

[0100] In the lighting device (1) according to the twelfth aspect of the 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 paths (W11, W12) via a filter circuit (2). The capacitor (33) is connected between output terminals of the rectifier circuit (31).

[0101] The above-described lighting device (1) 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] In the lighting device (1) of the fourteenth aspect according to the present embodiment, in the thirteenth aspect, it is preferable that the lighting device (1) further includes a capacitor (33A) connected between output terminals of the rectifier circuit (31A).

[0105] The above-described lighting device (1) 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 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 above-described lighting device (1) 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 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-mentioned 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 Circuits 33, 33A capacitor 4 Lighting Load 5A, 5B, 5C lighting fixtures 511, 521, 522, 531 housing Lc1 1st common mode noise filter (common mode noise filter) Lc2 Second common mode noise filter (common mode noise filter) Ln1 First normal mode noise filter (normal mode noise filter) Ln2 Second normal mode noise filter (normal mode noise filter) Lc1*, Ln1*, Ln2* inductance W11, W12 feed line K1 Electrical element

Claims

1. a filter circuit electrically connected to a pair of power supply paths for supplying 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 includes: 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 two ends of the capacitor circuit and the lighting circuit, the first inductor circuit includes a series circuit of a first common mode noise filter and a first normal mode noise filter; The second inductor circuit includes a series circuit of a second common mode noise filter and a second normal mode noise filter. Lighting device.

2. 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 1.

3. The inductance of the first normal mode noise filter and the inductance of the second inductor circuit are equal.

3. The lighting device according to claim 1 or 2.

4. The first common mode noise filter and the first normal mode noise filter are composed of a choke coil. A lighting device according to any one of claims 1 to 3.

5. The second common mode noise filter and the second normal mode noise filter are composed of a choke coil. A lighting device according to any one of claims 1 to 4.

6. The lighting circuit comprises: a rectifier circuit that rectifies an AC voltage input from the pair of power supply paths via the filter circuit; a capacitor connected between the output terminals of the rectifier circuit; A lighting device according to any one of claims 1 to 5.

7. Further comprising a rectifier circuit electrically connected between the capacitor circuit and the second inductor circuit. A lighting device according to any one of claims 1 to 5.

8. Further comprising a capacitor connected between output terminals of the rectifier circuit. The lighting device of claim 7.

9. Further comprising an electric element electrically connected between the rectifier circuit and the second inductor circuit, The impedance of the electrical element does not change with frequency 9. The lighting device according to claim 7 or 8.

10. The lighting circuit has a switching circuit, The switching frequency of the switching circuit is 40 kHz or more and 500 kHz or less. A lighting device according to any one of the preceding claims.

11. A lighting device according to any one of claims 1 to 10, A housing for supporting the lighting device. Lighting fixtures.

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