JPH11111477A - Discharge lamp lighting device and lighting system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To heighten the power factor and lower the high frequency distortion by installing an inverter means and a main resonance means which is connected between a current rectifying means and an LC parallel resonance means and generates the starting voltage and the lamp current based on the high frequency output. SOLUTION: When a commercial a.c. power source (e) is turned on, charging electric current flows into a capacitor C4 through a capacitor C3 and an inductor L2 of an LC parallel resonance circuit 12 as an LC parallel resonance means from a full-wave rectifier 11 as a current rectifying means and the capacitor C4 is charged. Since the capacitor C3 and the inductor L2 of the LC parallel resonance circuit 12 are connected with the full-wave rectifier as a rectifying means, rush current is hardly generated. In the case the voltage of the commercial a.c. power source (e) is higher than the voltage of the capacitor C4, electric current constantly flows in from the commercial a.c. power source (e) and in the case the voltage of the commercial a.c. power source is lower than the voltage of the capacitor C4, electric current flows in only at the time when a transistor Q1 is turned off.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge lamp lighting device and a lighting device with reduced harmonics.

[0002]

2. Description of the Related Art Conventionally, as a discharge lamp lighting device of this type, for example, a configuration described in Japanese Patent Application Laid-Open No. 8-149845 is known.

Japanese Patent Application Laid-Open No. 8-149845 discloses that
A half-bridge type inverter circuit having a pair of switching elements is connected to the diode bridge, a valley circuit is connected to the pair of switching elements of the inverter circuit, and an LC is connected between the diode bridge and the inverter circuit.
A parallel resonance circuit is connected.

In the valley filling circuit, a part of the energy from the inverter circuit is stored during a period when the output voltage of the diode bridge is high, and a voltage based on the stored energy is applied to the switching element during a period when the output voltage is low. When the output voltage from the diode bridge is low, the terminal voltage of the valley-filled circuit also decreases, the potential drop of the LC parallel resonance circuit decreases, and the peak value of the supply current is suppressed to reduce the fluctuation range of the current. ,
A configuration in which the input current distortion is improved is described.

[0005]

However, the configuration described in Japanese Patent Application Laid-Open No. 8-149845 is applied to a half-bridge type inverter and has a problem that can be applied only to this configuration. .

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and provides a discharge lamp lighting device and a lighting device which prevent an inrush current at the time of turning on a power source, increase a power factor and reduce harmonic distortion. With the goal.

[0007]

According to a first aspect of the present invention, there is provided a discharge lamp lighting device comprising: a rectifier for rectifying an alternating current; a smoother for smoothing an output rectified by the rectifier; A single-type voltage-resonant inverter means for converting; a high-frequency output of the inverter means interposed between the rectifying means and the smoothing means, and resonating at a lower frequency than the operating frequency of the inverter means, and a voltage at both ends is rectified; LC parallel resonance means set higher than the output voltage of the means; connected between the inverter means, the rectification means and the LC parallel resonance means, for forming a starting voltage and a lamp current based on a high-frequency output to light the discharge lamp. Main resonance means. And when the AC power is turned on,
The non-smooth direct current rectified by the rectifying means charges the smoothing means via the LC parallel resonance means. However, since the impedance of the LC parallel resonance means is interposed in this charging path, a large inrush current does not occur. Thereafter, as the terminal voltage of the smoothing means rises, the inverter means is activated and outputs a high frequency. This high-frequency output resonates at the main resonance means and is applied to the LC parallel resonance means, so that the LC parallel resonance means resonates at high frequencies. As a result, the voltage at both ends of the LC parallel resonance means has a high frequency whose amplitude is larger than the instantaneous value of the output voltage of the rectification means. Further, the resonance voltage of the LC parallel resonance means and the output voltage of the rectification means are added vectorwise and applied between both ends of the smoothing means. Therefore, when the instantaneous value of the voltage between the terminals of the LC parallel resonance means is higher than the instantaneous value of the output voltage of the rectification means, no current can flow from the rectification means into the smoothing means. When the voltage between both ends of the LC parallel resonance means is higher than the output voltage of the rectification means, the high frequency current from the LC parallel resonance means is fed back to the smoothing means. As a result, current flows intermittently from the rectifier to the smoothing unit in accordance with the high frequency cycle over the entire phase of the output voltage of the rectifier. Then, by charging the smoothing means,
The current flowing from the AC power supply into the rectifier has a waveform in which the high-frequency ripple is superimposed, but flows through the entire half cycle of the AC voltage, that is, in the same phase as the power supply voltage, and flows without a pause, and The harmonics of the current are reduced, the harmonics of the input current are reduced, and the power factor is high. On the other hand, when the output of the inverter circuit is applied to the main resonance means, the discharge lamp does not start at first, so it resonates under the resonance conditions at the time of starting, and generates a starting voltage at both ends of the discharge lamp. When lit, the lamp current is supplied under the lighting conditions.

According to a second aspect of the present invention, there is provided a discharge lamp lighting device according to the first aspect, wherein the inverter means comprises:
It has switching means, and the switching means operates by feeding back a load current including a lamp current of the discharge lamp. Then, the switching means is appropriately switched by feeding back the lamp current to operate the switching means.

A discharge lamp lighting device according to a third aspect of the present invention includes a rectifier for rectifying an alternating current; a smoother for smoothing an output rectified by the rectifier; an inverter for converting the output of the smoother to a high frequency; A frequency-dependent impedance means interposed between the rectifying means and the smoothing means and turned on during a period for charging the smoothing means and turned off during a period for discharging the smoothing means; and between the inverter means and the rectifying means and the impedance means. And a main resonance means for generating a starting voltage and a lamp current based on the high-frequency output and lighting the discharge lamp. Then, when the AC power supply is turned on, the non-smoothed DC rectified by the rectifying unit charges the smoothing unit via the impedance unit. However, since the impedance of the impedance unit is interposed in this charging path, a large inrush current does not occur. . Thereafter, as the terminal voltage of the smoothing means rises, the inverter means is activated and outputs a high frequency. This high frequency output resonates with the main resonance means,
Since the impedance means is applied to the impedance means, the impedance means resonates at a high frequency. As a result, the voltage at both ends of the impedance means becomes a high frequency whose amplitude is larger than the instantaneous value of the output voltage of the rectification means. Also, between both ends of the smoothing means, the impedance means turns on while the smoothing means is charged and turns off while the smoothing means discharges, and the voltage of the impedance means and the output voltage of the rectifying means are added vectorwise. Applied. For this reason, when the instantaneous value of the voltage between the terminals of the impedance means is higher than the instantaneous value of the output voltage of the rectification means, no current can flow from the rectification means into the smoothing means. When the voltage between both ends of the impedance means is higher than the output voltage of the rectification means, the high-frequency current from the impedance means is fed back to the smoothing means.
As a result, current flows intermittently from the rectifier to the smoothing unit in accordance with the high frequency cycle over the entire phase of the output voltage of the rectifier. When the smoothing means is charged, the current flowing from the AC power supply to the rectification means has a waveform in which the high-frequency ripple is superimposed, but throughout the entire half cycle of the AC voltage, that is, in phase with the power supply voltage. In addition, the current flows without a pause and the harmonics of the input current are reduced, the harmonics of the input current are reduced, and the power factor is increased. On the other hand, when the output of the inverter circuit is applied to the main resonance means, the discharge lamp does not start at first, so it resonates under the resonance conditions at the time of starting, and generates a starting voltage at both ends of the discharge lamp. When lit, the lamp current is supplied under the lighting conditions.

According to a fourth aspect of the present invention, there is provided a discharge lamp lighting device according to any one of the first to third aspects, further comprising a resonance capacitor connected between the full-wave rectifier and the inverter means. It is. Then, both the crest factor and the power factor are improved by the resonance capacitor.

According to a fifth aspect of the present invention, there is provided an illuminating apparatus including the discharge lamp lighting device according to any one of the first to fourth aspects, and a fixture main body provided with the discharge lamp lighting device. The discharge lamp lighting device according to any one of claims 1 to 4 has the respective functions.

[0012]

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

FIG. 1 is a circuit diagram showing a discharge lamp lighting device, and FIG.
3 is a circuit diagram showing a discharge lamp lighting device, and FIG. 3 is a perspective view showing the appearance of the lighting device. The lighting device shown in FIG.
A reflective surface 2 is formed on the lower surface of the light emitting device, and lamp sockets 3 and 3 are formed at both ends of the reflective surface 2. A fluorescent lamp FL as a discharge lamp is electrically connected between the lamp sockets 3 and 3.
The discharge lamp lighting device 4 shown in FIG.

Further, as shown in FIG. 1, the discharge lamp lighting device 4 is a full-wave rectifier of a diode bridge as a rectifier to a 50 Hz or 60 Hz low frequency commercial AC power supply e.
An input terminal of the full-wave rectifier 11 is connected to a smoothing circuit 13 as a smoothing means via an LC parallel resonance circuit 12 as an LC parallel resonance means. In parallel, a bypass capacitor C1, a main resonance circuit 14 as main resonance means, and a single-type voltage resonance type inverter circuit 15 of 1 kHz or more, preferably 20 kHz or more as inverter means are connected.
Further, the main resonance circuit 14 has an inductor L1, a capacitor C2, and a load 16, and the inverter circuit 15 has a switching means 17.

More specifically, as shown in FIG.
The LC parallel resonance circuit 12 includes a capacitor C3 and an inductor.
The smoothing circuit 13 includes a capacitor C4 having a capacity sufficient to smooth the voltage of the commercial AC power supply e, and the load 16 includes a coupling capacitor C5, a ballast choke L3, and a fluorescent lamp FL. The filament FL1,
FL2 is connected in series, and these filaments FL1, FL2
Between them, a capacitor C6 for resonance at the time of starting is connected. The switching means 17 includes a transistor Q1 and a diode D1. Note that the resonance frequency of the LC parallel resonance circuit 12 of the capacitor C3 and the inductor L2 is set to a frequency lower than the rated operating frequency of the inverter circuit 15, and the operating frequency of the inverter circuit 15 changes. It is set lower than the lowest frequency.

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

First, when the commercial AC power supply e is turned on, a charging current flows from the full-wave rectifier 11 to the capacitor C4 via the capacitor C3 of the LC parallel resonance circuit 12 and the inductor L2,
Charge the capacitor C4. The full-wave rectifier 11 has LC
Since the capacitor C3 and the inductor L2 of the parallel resonance circuit 12 are connected, an inrush current hardly occurs.

The voltage of the commercial AC power supply e is
When the voltage is higher than the voltage of C4, as shown in FIG. 8, the current always flows from the commercial AC power supply e, but the commercial AC power supply e
Is lower than the voltage of the capacitor C4, the operation is as shown in FIGS.

First, as shown in FIG.
Is on, the capacitor C4 is the power supply, the capacitor C4, the inductor L1, and the transistor of the inverter circuit 15.
A current flows through the path of Q1 and the capacitor C4, energy is supplied to the inverter circuit 15, and the voltage of the capacitor C4 gradually decreases. Also, the transistor Q1, the capacitor C3 and the inductor L2 of the LC parallel resonance circuit 12, the fluorescent lamp F
Current flows through the path of L, ballast choke L3, capacitor C5, and transistor Q1.

Next, as shown in FIG.
Turns off, the capacitor C2 is in resonance, and the capacitors C1, inductor L1, capacitor C2 and capacitor C1
Current flows in the path of the ballast choke L3,
Current flows through the paths of the capacitor C5, the capacitor C3, the capacitor C3 of the LC parallel resonance circuit 12, the inductor L2, the fluorescent lamp FL, and the ballast choke L3, and the voltage of the capacitor C4 further decreases.

Then, when the resonance state is reversed, as shown in FIG. 6, the capacitors C1, C2, and inductor L1
And the current flows through the path of the capacitor C1, and the ballast choke L3, the fluorescent lamp FL, the LC parallel resonance circuit 12
A current flows through the path of the capacitor C3 and the inductor L2, the capacitor C2, the capacitor C5, and the ballast choke L3, and the capacitor C4 is charged.

Further, as shown in FIG.
1.Current flows in the path of the capacitor C1, the capacitor C2 and the inductor L1, and also in the path of the ballast choke L3, the fluorescent lamp FL, the capacitor C3 and the inductor L2, the capacitor C2, the capacitor C5 and the ballast choke L3 of the LC parallel resonance circuit 12. Electric current flows.

That is, when the voltage of the commercial AC power supply e is lower than the voltage of the capacitor C4, current flows only when the transistor Q1 is off, as shown in FIG.

Next, a discharge lamp lighting device 21 according to another embodiment is described.
Will be described with reference to FIG.

FIG. 10 shows a discharge lamp lighting device according to another embodiment.
In the discharge lamp lighting device 21 shown in FIG. 2, the smoothing circuit 13 includes a series circuit of a smoothing capacitor C7, an inductor L4, and a diode D2. Connect a diode D3 between the connection point of D2 and the collector of transistor Q1,
Connection point of inductor L1 and capacitor C5 and capacitor
Connect the primary winding CT1a of the feedback saturable current transformer CT1 between C2 and C2, and connect the series circuit of the diode D4 and the resistor R1 between the base and the emitter of the transistor Q1, and the secondary of the saturable current transformer CT1. It is self-excited by connecting a winding CT1b and a series circuit of a capacitor C8. Note that the frequency characteristics of the impedance circuit 20 formed by the capacitor C3 and the inductor L2 are as shown in FIG.
The frequency when the instantaneous voltage of the commercial AC power supply e is low is fL, the frequency when the instantaneous voltage is high is fH, the resonance frequency is f0, and the average frequency is favg.

Then, self-excitation is controlled by the saturable current transformer CT. At this time, when the instantaneous voltage of the commercial AC power supply e is high, as shown in FIG.
Early timing t1 because the current flowing through CT1 has a large gradient
When the instantaneous voltage is low, the current flowing through the saturable current transformer CT1 has a small gradient, as shown in FIG. 13, and saturates at a later timing t2, and the operating frequency becomes fL. And lower. Therefore, the voltage generated at both ends of the LC parallel resonance circuit 12 is changed to the commercial AC power supply e by the relationship between the capacitor C3 of the LC parallel resonance circuit 12 and the parallel resonance circuit of the inductor L2 shown in FIG.
Can be changed by the instantaneous voltage.

That is, when the instantaneous voltage of the commercial AC power supply e is high, a large voltage is not generated in the LC parallel resonance circuit 12, and when the instantaneous voltage of the commercial AC power supply e is low, it is generated in the LC parallel resonance circuit 12. When the voltage increases and is superimposed on the voltage of the commercial AC power supply e, the voltage value across the capacitor C3 changes as shown in FIG. 14, and the power factor is effectively improved.

In the discharge lamp lighting device 21 shown in FIG. 10, the primary winding CT1a of the saturable current transformer CT1 is connected to the connection point between the inductor L1 and the capacitor C2 and the transistor Q1.
The same effect can be obtained by connecting between the collector of the inductor L1 and the collector of the transistor Q1 and the capacitor C5 as shown in FIG. Can be obtained.

Next, a discharge lamp lighting device 22 according to another embodiment will be described.
Will be described with reference to FIG.

FIG. 16 is a circuit diagram showing a discharge lamp lighting device according to another embodiment. The discharge lamp lighting device 22 shown in FIG.
Corresponds to the smoothing circuit 13 in the discharge lamp lighting device 4 shown in FIG.
Into a smoothing circuit 13 shown in FIG. 10, and an impedance means 20 is connected in series to the smoothing circuit 13 so that the fluorescent lamp FL
Are connected in parallel to the inductor L1.

Further, this impedance means 20 is provided in FIG.
As shown in FIG. 7, a parallel circuit of a diode D4 as a switching element having a forward polarity with respect to the current rectified by the full-wave rectifier 11 and a capacitor C11 is provided.

When the instantaneous voltage of the commercial AC power supply e is high, the smoothing circuit is turned on by turning on the diode D4.
13 and operates similarly to the discharge lamp lighting device 4 shown in FIG.

On the other hand, when the instantaneous voltage of the commercial AC power supply e is low, the capacitor C7 discharges, and the capacitor C11, the inductor L1, the transistor Q1, the diode D2,
Current flows through the path of L4, capacitor C7 and capacitor C11, and the capacitor C7 side of capacitor C11 is charged to the positive electrode. Also, the voltage of the capacitor C11 is
When the sum of them becomes higher than that of the smoothing circuit 13, the full-wave rectifier 11 is turned on, a current flows from the commercial AC power supply e, and the full-wave rectifier 11, the capacitor C11, the capacitor C7, the inductor L4, Transistor Q1 and full-wave rectifier
It flows on 11 routes. At this time, the diode D4 is turned off because a voltage of the opposite polarity is applied, and no current flows.

Further, a discharge lamp lighting device 23 according to another embodiment
Will be described with reference to FIG.

FIG. 18 is a circuit diagram showing a discharge lamp lighting device according to another embodiment. The discharge lamp lighting device 23 shown in FIG.
In the discharge lamp lighting device 21 shown in FIG. 10, the LC parallel resonance circuit 12 is connected to the smoothing circuit 13 in series.

In this case, the operation basically becomes as shown in FIG.

Further, a discharge lamp lighting device according to another embodiment
24 will be described with reference to FIG.

FIG. 19 is a circuit diagram showing a discharge lamp lighting device according to another embodiment. The discharge lamp lighting device 24 shown in FIG.
In the embodiment shown in FIG. 1, the load 16 is connected in parallel to the inductor L1, and a resonance capacitor C12 is connected between the negative electrode of the full-wave rectifier 11 and the collector of the transistor Q1. .

Further, as shown in FIG. 20, the position of the LC parallel resonance circuit 12 is located on the positive side of the full-wave rectifier circuit 11,
Accordingly, the same effect can be obtained even if the position of the resonance capacitor C12 is changed.

Also, as shown in FIG. 21, the same effect as that shown in FIG. 10 can be basically obtained by adopting the self-excited structure as in FIG.

In any of the embodiments, the inverter means is not limited to a single type but may be a half bridge type.

[0042]

According to the discharge lamp lighting device of the first aspect, the resonance voltage of the LC parallel resonance means and the output voltage of the rectification means are applied to the smoothing means in a vector manner, and the output of the rectification means is applied. Over the entire phase of the voltage, current flows intermittently from the rectifier into the smoothing unit in accordance with the high-frequency cycle, and the current flowing from the AC power supply into the rectifier has a waveform in which the high-frequency ripple is superimposed. It flows in the same phase as above without a pause and can reduce the harmonics of the input current, reduce the harmonics of the input current, and achieve a high power factor.

According to the discharge lamp lighting device of the second aspect,
In addition to the discharge lamp lighting device according to the first aspect, the switching means can be appropriately switched by feeding back the lamp current to operate the switching means.

According to the discharge lamp lighting device of the third aspect,
The resonance voltage of the impedance means and the output voltage of the rectification means are applied to the smoothing means in a vector-wise manner. Flows into the smoothing means,
The current flowing from the AC power supply to the rectifier has a waveform in which high-frequency ripple is superimposed, but flows in the same phase as the power supply voltage without a pause, thereby reducing harmonics of the input current and harmonics of the input current. And a high power factor.

According to the discharge lamp lighting device of the fourth aspect,
In addition to the discharge lamp lighting device according to any one of claims 1 to 3, both the crest factor and the power factor can be improved by the capacitor for resonance.

The lighting device according to the fifth aspect has the fixture main body provided with the discharge lamp lighting device according to any one of the first to fourth aspects, so that the respective effects can be obtained.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a discharge lamp lighting device according to the present invention.

FIG. 2 is a circuit diagram more specifically showing the above.

FIG. 3 is a perspective view showing an appearance of the lighting device.

FIG. 4 is a circuit diagram showing an operation of the discharge lamp lighting device shown in FIG. 2;

FIG. 5 is a circuit diagram showing the next operation of FIG. 4;

FIG. 6 is a circuit diagram showing the next operation of FIG. 5;

FIG. 7 is a circuit diagram showing the next operation of FIG. 6;

FIG. 8 is a waveform chart showing each current value and voltage value when the instantaneous voltage of the commercial AC power supply is high.

FIG. 9 is a waveform chart showing each current value and voltage value when the instantaneous voltage of the commercial AC power supply is low.

FIG. 10 is a circuit diagram showing a discharge lamp lighting device according to another embodiment of the present invention.

FIG. 11 is a circuit diagram showing a relationship between frequency and impedance according to the first embodiment;

FIG. 12 is a waveform chart showing the collector current of the transistor Q1 in the state where the instantaneous voltage is high.

FIG. 13 is a waveform chart showing the collector current of the transistor Q1 when the instantaneous voltage is low.

FIG. 14 is a waveform chart showing a relationship between the commercial AC power supply and the voltage value of the capacitor C3.

FIG. 15 is a circuit diagram showing a part of a discharge lamp lighting device according to another embodiment of the present invention.

FIG. 16 is a circuit diagram showing a discharge lamp lighting device according to another embodiment of the present invention.

FIG. 17 is a circuit diagram showing a discharge lamp lighting device according to still another embodiment of the present invention.

FIG. 18 is a circuit diagram showing a discharge lamp lighting device according to still another embodiment of the present invention.

FIG. 19 is a circuit diagram showing a discharge lamp lighting device according to another embodiment of the present invention.

FIG. 20 is a circuit diagram showing a discharge lamp lighting device according to another embodiment of the present invention.

FIG. 21 is a circuit diagram showing a discharge lamp lighting device according to still another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Apparatus main body 4,21,22,23 Discharge lamp lighting device 11 Full-wave rectifier as rectification means 12 LC parallel resonance circuit as LC parallel resonance means 13 Smoothing circuit as smoothing means 14 Main resonance circuit as main resonance means 15 Inverter circuit as inverter means 20 Impedance means FL Fluorescent lamp as discharge lamp

Claims (5)

[Claims] A rectifying means for rectifying an alternating current; a smoothing means for smoothing an output rectified by the rectifying means; a single-type voltage resonance type inverter means for converting an output of the smoothing means into a high frequency; LC parallel resonance means interposed between the smoothing means and the high frequency output of the inverter means, applied to resonate at a frequency lower than the operating frequency of the inverter means, and having a voltage at both ends set higher than the output voltage of the rectifier means; Main discharge means connected between the inverter means and the rectification means and the LC parallel resonance means for forming a starting voltage and a lamp current based on a high-frequency output and lighting the discharge lamp; Lighting device. 2. The discharge lamp lighting device according to claim 1, wherein the inverter has switching means, and the switching means operates by feeding back a load current including a lamp current of the discharge lamp. Rectifying means for rectifying an alternating current; smoothing means for smoothing an output rectified by the rectifying means; inverter means for converting the output of the smoothing means to a high frequency; A frequency-dependent impedance means, which is turned on during charging of the inserted smoothing means and turned off during feedback of the smoothing means; connected between the inverter means, the rectifying means and the impedance means, and provided with a starting voltage based on a high-frequency output. And a main resonance means for forming a lamp current and lighting the discharge lamp. 4. The discharge lamp lighting device according to claim 1, further comprising a resonance capacitor connected between the full-wave rectifier and the inverter means. 5. A lighting device, comprising: the discharge lamp lighting device according to claim 1; and a fixture main body provided with the discharge lamp lighting device.