JP2000023451A - Power supply device, discharge lamp lighting device and lighting device - Google Patents

Abstract

(57) [Problem] To provide a discharge lamp lighting device in which a leakage current is suppressed. SOLUTION: A full-wave rectifier circuit 12 performs full-wave rectification on an AC voltage of a commercial AC power supply e, and switches a field effect transistor Q1, thereby boosting a voltage by a step-up chopper circuit 13 and improving a power factor. The output voltage of the step-up chopper circuit 13 is switched between the field-effect transistor Q2 and the field-effect transistor Q3 to generate a high-frequency alternating current.
, FL2 starts and lights up. The leakage current is suppressed by the grounding capacitor C3, and particularly by connecting to the vicinity of the field effect transistor Q3, high frequency noise is suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device, a discharge lamp lighting device, and a lighting device in which leakage current is suppressed.

[0002]

2. Description of the Related Art Conventionally, as a discharge lamp lighting device of this type, for example, a low frequency voltage of a commercial AC power supply is rectified and smoothed, and the rectified and smoothed voltage is switched to a high frequency by switching a switching element of an inverter circuit at a high frequency. Convert and turn on the fluorescent lamp. Further, a leakage capacitor is reduced by connecting a ground capacitor to a low-frequency portion on the commercial AC power supply side from the inverter circuit.

[0003]

However, when a ground capacitor is connected to a low-frequency part, there is a problem that high-frequency noise cannot be sufficiently reduced.

The present invention has been made in view of the above problems, and has as its object to provide a power supply device, a discharge lamp lighting device, and a lighting device in which high-frequency noise is reduced and leakage current is suppressed.

[0005]

According to a first aspect of the present invention, there is provided a power supply apparatus comprising: a case body having conductivity; a conversion circuit housed in the case body and having a switching element that is turned on and off at a high frequency; A grounding capacitor connected between the vicinity and the case body,
By connecting a ground capacitor near the switching element and between the case bodies, noise due to high frequency is suppressed.

According to a second aspect of the present invention, there is provided a power supply device, a case body having conductivity; a heat sink attached to the case body at the same potential as the case body; and a high frequency mounted on the heat sink to turn on and off. A conversion circuit having a switching element; and a grounding capacitor connected near the switching element and between the heat sinks. By connecting a grounding capacitor near the switching element and between the case bodies, noise due to high frequency is generated. Suppress.

According to a third aspect of the present invention, there is provided a power supply device comprising: a case body having conductivity; a conversion circuit for converting a low frequency from a power supply to a high frequency; a ground capacitor and a common mode transformer, and a low frequency leakage current; 1/2 of high frequency leakage current
A noise prevention circuit in which the capacitance of the grounding capacitor and the inductor of the common mode transformer are set so that 0 is equal. The noise prevention circuit includes 1/20 of the low frequency leakage current and the high frequency leakage current. The leakage current is suppressed by setting the capacitance of the ground capacitor and the inductor of the common mode transformer such that the following equation is obtained.

According to a fourth aspect of the present invention, in the discharge lamp lighting device, the power supply device according to the third aspect of the present invention lights the discharge lamp, and is connected between the power supply device and the case body to connect a detection resistor for detecting a leakage current. The lamp voltage is VL [V], the reactance of the ground capacitor is XCy [Ω], the inductance of the common mode transformer is XL [Ω], the detection resistance is R [Ω], and the reactance of the equivalent stray capacitance between the discharge lamp and the case body. To X
When Cs [Ω], Re ((VL / z) × (XCy /
(XCy + (XL ² + R ² ) ^1/2 ))) ≦ 20 mA, Z =
((XCy × XL + XCs × XL + XCs × XCy) + jR (X
Cy−XCs)) / (R + j (XL−XCy)), which suppresses leakage current due to high frequency.

According to a fifth aspect of the present invention, there is provided a discharge lamp lighting device including the power supply device according to any one of the first to third aspects for lighting a discharge lamp.

According to a sixth aspect of the present invention, there is provided a lighting device comprising: a fixture main body to which a discharge lamp is mounted; and a discharge lamp lighting device according to the fourth or fifth aspect for lighting the discharge lamp.
Each function is performed.

[0011]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a lighting device according to an embodiment of the present invention.

FIG. 2 is a perspective view showing the external appearance of the lighting apparatus. The fixture body 1 is an inverted Fuji type and has reflecting surfaces 2 and 2 on its lower surface. These reflecting surfaces 2 have lamp sockets 3 and 3 at both ends. Fluorescent lamps FL1 and FL2 serving as discharge lamps are electrically and mechanically mounted between the lamp sockets 3 and 3, respectively. The discharge lamps are called electronic ballasts shown in FIG. The lighting device 5 is housed.

FIG. 1 is a circuit diagram showing a discharge lamp lighting device. The discharge lamp lighting device 5 shown in FIG. 1 is connected to a commercial AC power supply e having a commercial frequency of 50 Hz or 60 Hz as a noise prevention circuit. The filter circuit 11 is connected, and the input terminal of the full-wave rectifier circuit 12 is connected to the filter circuit 11.

An output terminal of the full-wave rectifier circuit 12 has a boost chopper circuit 13 as a pre-regulator circuit.
This boost chopper circuit 13 is connected to the full-wave rectifier circuit 12
, A series circuit of an inductor L1 and a field effect transistor Q1 as a switching element is connected, and a diode D1 and a capacitor C1 are connected in parallel to the field effect transistor Q1.

A half-bridge type inverter circuit 14 as a conversion circuit is connected to the step-up chopper circuit 13. This inverter circuit 14 includes a field effect transistor Q2 and a field effect transistor Q3 as switching elements for high frequency switching. A series circuit is connected.

Further, in parallel with the field effect transistor Q3, a DC cut capacitor C2, an inductor L2,
Through the capacitor C4 and the balancer L3, the fluorescent lamps FL1,
FL2 is connected.

The discharge lamp lighting device 5 is housed in a metal case 15 having conductivity, and a ground capacitor C3 is connected near the field effect transistor Q3.
Grounded to 15.

Next, the operation of the above embodiment will be described.

First, the AC voltage of the commercial AC power supply e is full-wave rectified by the full-wave rectifier circuit 12 and the field-effect transistor Q1 is switched, so that the voltage is boosted by the boost chopper circuit 13 and the power factor is improved.

The output voltage of the step-up chopper circuit 13 is switched between the field-effect transistor Q2 and the field-effect transistor Q3 to generate a high-frequency alternating current.
1. Start and light up FL2.

Further, the leakage current is suppressed by the grounding capacitor C3, and particularly high frequency noise is suppressed by being connected near the field effect transistor Q3.

Here, FIG. 3 is a diagram showing the embodiment of FIG.
A graph showing a frequency of 5 MHz to 5 MHz and a noise amount,
FIG. 4 shows the embodiment shown in FIG.
5 is a graph showing the frequency and noise amount of 0 MHz to 5 MHz of a comparative example in which a ground capacitor is connected near the full-wave rectifier circuit, and FIG. 6 is a graph showing the noise amount near the full-wave rectifier circuit. It is a graph which shows the frequency of 5 MHz-30 MHz and the amount of noise of the comparative example which connected the grounding capacitor.

When comparing FIGS. 3 and 5, the low-frequency noise amount is almost the same, but when comparing FIGS. 4 and 6, the high-frequency noise amount is sufficiently reduced.

Next, another embodiment will be described with reference to FIG.

FIG. 7 is a circuit diagram showing a discharge lamp lighting device according to another embodiment. The embodiment shown in FIG. 7 is different from the embodiment shown in FIG. Instead of the vicinity, the field effect transistor Q2
Are connected in the vicinity of.

As described above, the same effect can be obtained even if the ground capacitor C3 is connected near the field effect transistor Q2.

FIGS. 8 to 10 show another embodiment.
This will be described with reference to FIG.

FIG. 8 is a circuit diagram showing a discharge lamp lighting device according to another embodiment, FIG. 9 is a perspective view showing a case body with a part cut away, and FIG. 10 is a plan view showing the case body.

As shown in FIG. 9 and FIG.
A recess 21 is formed in the recess 15, and an auxiliary heat dissipation plate 22 corresponding to the recess 21 and being flush with the recess 21 is housed in the recess 21. Fixed.

The grounding capacitor C3 is connected to the substrate 24 by screws 25.
It is attached at.

The embodiment shown in FIGS. 8 to 10 has the same effect as the embodiment shown in FIG. In addition, when the grounding capacitor C3 is grounded, it is not necessary to use a special screw or the like, so that mounting and connection can be easily performed.

Further, another embodiment will be described with reference to FIG.

FIG. 11 is a circuit diagram showing a discharge lamp lighting device.
The embodiment shown in FIG. 11 is different from the embodiment shown in FIG. 1 in that a filter circuit 11 including a common mode transformer Tr is provided at the input end, a full-wave rectifier circuit 12, a boost chopper circuit 13 which is a pre-regulator circuit, and Inverter circuit 14
Are connected in cascade and have equivalent stray capacitances C7 and C8 determined by the distance between the electronic ballast such as the fluorescent lamps FL1 and FL2 and the discharge lamp lighting device 5 and the fixture main body 1, such as the inverter circuit 14, and the like. . Where the stray capacitance is the fluorescent lamp
Although they exist in a distributed manner along FL1 and FL2, the equivalent stray capacitances C7 and C8 are assumed to exist as lumped constants between the high potential end and the stable potential. Of the fluorescent lamps FL1 and FL2.

FIG. 12 is a circuit diagram showing a method of measuring a leakage current described in the Electrical Appliance and Material Control Law. The discharge lamp lighting device 5 shown in FIG. 11 corresponds to a tester specified by law and an inverter. Electronic ballast part such as circuit 14, fluorescent lamp FL1
, FL2 and an instrument body 1 to which these fluorescent lamps FL1, FL2 are attached. The connection of the detection resistor R1 is switched by the switch SW.

Here, an equivalent circuit relating to the low frequency component of the leakage current will be described with reference to FIG.

When the frequency is low, as shown in FIG. 13, the common mode transformer Tr is in a low impedance state and is considered to be short-circuited. Therefore, the detection resistance R1 of 1 kΩ corresponds to the reactance XCy of the ground capacitor C6. A leakage current flows as shown in FIG. Then, the smaller the reactance XCy of the ground capacitor C6, the smaller the leakage current.

An equivalent circuit at a high frequency will be described with reference to FIGS.

At the time of high frequency, they are connected as shown in FIG. 15, and the fluorescent lamps FL1, FL2 are represented by a lamp equivalent resistance RFL. Also, as shown in FIG. 16, the noise prevention capacitor C5 has a low impedance and is considered to be short-circuited.
Further, as shown in FIG. 17, since the lamp equivalent resistance RFL is connected in parallel to the inverter circuit 14 serving as a high-frequency power supply, it does not affect the required leakage current.
As shown in FIG. 18, a leakage current flows through the 1 kΩ detection resistor R1 with respect to the reactance XCy of the ground capacitor C6. Then, as the reactance XCy of the ground capacitor C6 increases, the leakage current decreases.

Here, since the regulation regarding the leakage current is based on the frequency characteristic of sensing the electric shock of the human body, the high frequency component is 20 times or less, which is 20 times the low frequency of 1 mA or less when the frequency is 30 kHz or more. Is allowed as a leakage current. Since the lighting frequency of the fluorescent lamps FL1 and FL2 is often 45 KHz or more, the leakage current of the high frequency component is reduced to 1/20, and the leakage current of the high frequency component and the leakage current of the low frequency component are combined. As shown in FIG. 19, the leakage current is specified by the electrical equipment standard by setting the reactance XCy of the ground capacitor C6 to a minimum at a predetermined value and setting the current of the low frequency component equal to 1/20 of the high frequency component leakage current. The leakage current due to the measured method can be minimized.

Further, the input voltage of the commercial AC power
Assuming that the fluorescent lamps FL1 and FL2 are 0 V, the frequency is 50 Hz, the fluorescent lamps FL1 and FL2 are manufactured by Toshiba Lighting & Technology Corporation, and the model voltage is FHP105, the lamp voltage is 350 V, the lighting frequency is 60 kHz, and the common mode transformer is 9 mH, as shown in FIG. From 3000 pF to 450
By setting it to 0 pF, the leakage current is minimized.

Here, when the leakage current is mainly a high-frequency current, the lamp voltage of the fluorescent lamps FL1 and FL2 is changed to VL.
[V], the reactance of the ground capacitor C6 is XCy
[Ω], the inductance of the common mode transformer Tr is X
L [Ω], detection resistor R1 is R [Ω], fluorescent lamps FL1, FL
XCs is the reactance of the equivalent stray capacitance between 2 and case body 15.
[Ω], Re ((VL / z) × (XCy / (XCy + (XL ² +
R ² ) ^1/2 ))) ≦ 20 mA, Z = ((XCy × XL + XCs × XL + XCs × XCy) + jR
(XCy-XCs)) / (R + j (XL-XCy)).

[0042]

According to the power supply device of the first aspect, by connecting the grounding capacitor near the switching element and between the case bodies, noise due to high frequency can be suppressed.

According to the power supply device of the second aspect, by connecting the grounding capacitor in the vicinity of the switching element and between the case bodies, noise due to high frequency can be suppressed.

According to the power supply device of the third aspect, the noise prevention circuit is configured to provide one / one of the low frequency leakage current and the high frequency leakage current.
By setting the capacitance of the ground capacitor and the inductor of the common mode transformer so that 20 is equal, the leakage current can be suppressed.

According to the discharge lamp lighting device of the fourth aspect,
The power supply device according to claim 3 turns on the discharge lamp, connects to the case body, connects a detection resistor for detecting a leak current, sets the lamp voltage of the discharge lamp to VL [V], and sets the reactance of the grounding capacitor. XCy [Ω], the inductance of the common mode transformer is XL [Ω], and the detection resistance is R.
[Ω], and when the reactance of the equivalent stray capacitance between the discharge lamp and the case body is XCs [Ω], Re ((VL / z)
× (XCy / (XCy + (XL ² + R ² ) ^1/2 )))) ≦ 20
mA, Z = ((XCy × XL + XCs × XL + XCs × XCy)
+ JR (XCy-XCs)) / (R + j (XL-XCy)), so that the leakage current can be suppressed.

According to the discharge lamp lighting device of the fifth aspect,
With the power supply device according to the fourth or fifth aspect of the present invention for lighting a discharge lamp, each effect can be obtained.

According to the illumination device of the sixth aspect, since the discharge lamp lighting device of the fourth or fifth aspect for lighting a discharge lamp is provided, the respective effects can be obtained.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing one embodiment of a discharge lamp lighting device of the present invention.

FIG. 2 is a perspective view showing an appearance of the lighting device.

FIG. 3 is a graph showing a voltage of a capacitor showing a relationship between a frequency of 0 MHz to 5 MHz and noise as in the above.

FIG. 4 is a graph showing a voltage of a capacitor showing a relationship between a frequency of 5 MHz to 30 MHz and noise as described above.

FIG. 5 is a graph showing a voltage of a capacitor showing a relationship between a frequency of 0 MHz to 5 MHz and noise in the conventional example.

FIG. 6 is a graph showing a voltage of a capacitor showing a relationship between a frequency of 5 MHz to 30 MHz and noise as described above.

FIG. 7 is a circuit diagram showing a discharge lamp lighting device according to another embodiment of the present invention.

FIG. 8 is a circuit diagram showing a discharge lamp lighting device according to another embodiment of the present invention.

FIG. 9 is a perspective view showing the case body with a part cut away.

FIG. 10 is a plan view showing the same case body.

FIG. 11 is a circuit diagram showing a discharge lamp lighting device according to another embodiment of the present invention.

FIG. 12 is a circuit diagram showing a method for measuring a leakage current described in the Electrical Appliance and Material Control Law.

FIG. 13 is an equivalent circuit diagram relating to a low frequency component of the leakage current.

FIG. 14 is a graph showing the relationship between the capacitance of the ground capacitor and the leakage current at the time of the low frequency.

FIG. 15 is an equivalent circuit diagram at the time of high frequency in Embodiment 1;

FIG. 16 is an equivalent circuit diagram at the time of the same high frequency.

FIG. 17 is an equivalent circuit diagram at the time of high frequency in Embodiment 1;

FIG. 18 is a graph showing the relationship between the capacitance of the ground capacitor and the leakage current at the time of high frequency.

FIG. 19 is a graph showing the relationship between the capacitance of the ground capacitor and the leakage current at the time of low frequency and at the time of high frequency.

FIG. 20 is a graph showing the relationship between the capacitance of the grounded capacitor and the leakage current.

[Explanation of symbols]

1 Apparatus body 5 Discharge lamp lighting device 11 Filter circuit as noise prevention circuit 14 Inverter circuit as conversion circuit 15 Case body 22 Auxiliary heat sink C3, C6 Grounding capacitor FL1, FL2 Fluorescent lamp as discharge lamp Q1, Q2 As switching element Field effect transistor R1 Detection resistor Tr Common mode transformer

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hirokazu Otake 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo Inside Toshiba Lighting & Technology Corporation (72) Inventor Kenichi Asami 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo Toshiba Lighting & Technology Corporation (72) Inventor Keiichi Shimizu 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo Toshiba Lighting & Technology Corporation (72) Inventor Kazutoshi Mita 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo Toshiba Shin-ichiro Matsumoto (72) Inventor Shinichiro Matsumoto 4-3-1 Higashi-Shinagawa, Shinagawa-ku, Tokyo Toshiba Lite-Tech Co., Ltd. F term (reference) 3K072 AA01 AB02 BA03 BA05 BB01 BB10 BC01 BC03 FA05 FA09 GA02 GB12 GC04 5E322 AA02 AA03 AB01 5H007 AA01 AA02 AA08 BB03 CA02 CB12 HA03 HA05 5H740 BA12 BB05 BB06 BB08 NN02 PP02 PP05

Claims (6)

[Claims] 1. A case body having conductivity; a conversion circuit housed in the case body and having a switching element that turns on and off at a high frequency; and a grounding capacitor connected near the switching element and between the case bodies; A power supply device comprising: 2. A case body having conductivity; a heat sink attached to the case body at the same potential as the case body;
A power supply device comprising: a conversion circuit attached to the heat radiating plate and having a switching element that turns on and off at a high frequency; and a grounding capacitor connected near the switching element and between the heat radiating plates. 3. A case body having conductivity; a conversion circuit for converting a low frequency from a power supply to a high frequency; and a grounding capacitor and a common mode transformer, wherein 1/1 of the low frequency leakage current and the high frequency leakage current. So that 20 is equal to
A power supply device comprising: a noise prevention circuit in which a capacitance of a ground capacitor and an inductor of a common mode transformer are set. 4. The power supply according to claim 3, wherein the discharge lamp is turned on, a detection resistor for detecting a leakage current is connected between the discharge lamp and the case body, and the lamp voltage of the discharge lamp is VL [V]; When the reactance of the ground capacitor is XCy [Ω], the inductance of the common mode transformer is XL [Ω], the detection resistance is R [Ω], and the reactance of the equivalent stray capacitance between the discharge lamp and the case is XCs [Ω]. Re ((VL / z) × (XCy / (XCy + (XL ² +
R ² ) ^1/2 ))) ≦ 20 mA, Z = ((XCy × XL + XCs × XL + XCs × XCy) + jR
(XCy-XCs)) / (R + j (XL-XCy)). 5. A discharge lamp lighting device comprising the power supply device according to claim 1 for lighting a discharge lamp. 6. A lighting device comprising: a fixture main body to which a discharge lamp is mounted; and the discharge lamp lighting device according to claim 4 for lighting the discharge lamp.