JP2001284094A - Discharge lamp lighting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an energy-saving discharge lamp lighting device that can light a lamp without decreasing the lamp life even starting a discharge lamp with lighting control. SOLUTION: The device consists of a power conversion part P supplying lighting power to a discharge lamp LA by inputting alternating power Vs and a discharge lamp LA connected with an output of the power conversion part P, and the light of discharge lamp LA is controlled by the power conversion part P. A light controlling change-over means A is also provided for switching a rated starting condition to a light controlling starting condition maintaining a vicinity of light flux of light control ratio according to the light control signal after light flux of the discharge lamp LA and the light flux of light control ratio in accordance with the light controlling signal get almost identical, by starting at a rated starting condition at light controlling starting time.

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 for lighting a high pressure discharge lamp such as a high pressure sodium lamp and a metal halide lamp.

[0002]

2. Description of the Related Art At present, high-pressure discharge lamps such as high-pressure sodium lamps and metal halide lamps are widely used in store lighting, road lighting, factory lighting, stadiums and the like depending on the application. As a lighting device for lighting these high pressure discharge lamps, a magnetic circuit type lighting device as shown in FIG. 5 is mainly used. A copper-iron ballast A composed of a filter capacitor C11 connected in parallel to the AC power supply Vs, a choke coil L11 connected in series to the AC power supply Vs, a charge / discharge capacitor C12, a charge capacitor C13, and pulse generation The igniter IG1 includes a transformer T11 and a thyristor Q11 for discharging a capacitor C12. The copper-iron ballast A is regarded as a current source, and charges the charging / discharging capacitor C12 and the charging capacitor C13. When the voltage between both ends of the charging / discharging capacitor C12 exceeds the turn-on voltage of the discharging thyristor Q11, the thyristor Q11 becomes conductive and the discharging current of the charging / discharging capacitor C12 flows through the primary winding of the pulse generating transformer T11, A pulse voltage is generated in the secondary winding of T11, and a starting voltage of the discharge lamp LA is generated.

A high-pressure sodium lamp used for road lighting, particularly for tunnel lighting, is illuminated thinly at night to save power, or employs a magnetic circuit lighting device for dimming as shown in FIG. Is dimming. In this circuit, a dimming choke coil L12 is connected in series between a copper-iron ballast A and an igniter IG1, and a contact RY1 of a dimming choke coil short-circuit relay is connected in parallel with the choke coil L12. By turning on and off the contact RY1 of the relay, the lamp current flowing through the high-pressure discharge lamp LA is adjusted to perform dimming.

[0004]

However, when the dimming of the discharge lamp LA is started with the lighting device as shown in FIG. 6, the dimming is started with the contact RY1 of the dimming choke coil short-circuiting relay turned off. As a result, the lamp current is reduced, and the current that is originally required at the time of starting the lamp is not supplied. Then, the time required for the discharge lamp LA to light up stably becomes longer, and at the same time, the state in which the electrodes of the discharge lamp LA are not sufficiently warmed becomes longer, which causes a short life of the discharge lamp LA.

[0005] For this reason, in the current operation, a method is used in which the lamp is first lit in the full lighting state and the light is dimmed when the discharge lamp LA is sufficiently stabilized. This consumes more lamp power, resulting in higher power consumption.

FIG. 7 shows a VI curve of the discharge lamp LA in FIG. First, the discharge lamp LA immediately after lighting is indicated by 100 in FIG.
The lighting is performed at the position of P1 on the VI curve S1 corresponding to the% lighting. From there, the lighting gradually shifts to a stable lighting on the VI curve S1 until the discharge lamp LA stabilizes at a point P2 at which the discharge lamp LA becomes stable.
The lighting power of the discharge lamp LA increases along the -I curve S1. After that, a transition is made to the VI curve S2 at the point P2 as a boundary.
A point P3 corresponding to a desired light flux is reached on the curve S2, and lighting is performed in a dimming state (50% dimming in FIG. 7). The hatched portion indicates the power consumption of the discharge lamp LA, and indicates that the lamp power consumed more than the lamp power required at the time of dimming is consumed before lighting in the dimming state. .

Further, as a system for outputting a dimming signal, when the lamp is started, the lamp is lit in a fully lit state, and the discharge lamp L
When A is stably turned on, control for shifting to dimming lighting is required.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to light a discharge lamp without diminishing the life of the lamp even when dimming of the discharge lamp is started, and to save energy in the discharge lamp. It is to provide a device.

[0009]

According to a first aspect of the present invention, there is provided a power conversion unit for inputting an AC power supply and supplying lighting power to a discharge lamp, and an output of the power conversion unit. A discharge lamp comprising a discharge lamp, and dimming the discharge lamp by the power conversion unit. The dimming according to the luminous flux of the discharge lamp and the dimming signal is performed by starting the lamp under rated starting conditions at the time of starting the dimming. After the luminous flux of the ratio substantially matches, while maintaining the vicinity of the luminous flux of the dimming ratio according to the dimming signal, it is characterized by having dimming switching means for switching the rated start condition to the dimming start condition, According to the configuration, dimming lighting is performed without adversely affecting the life of the lamp, and energy saving can be realized.

According to a second aspect of the present invention, in the first aspect of the present invention, the luminous flux determining means for determining that the luminous flux of the discharge lamp substantially matches the luminous flux of the dimming ratio according to the dimming signal is provided. Lamp voltage detection that compares the light flux of the discharge lamp with the light flux of the dimming ratio according to the dimming signal by comparing the reference voltage corresponding to the light flux with the dimming ratio according to the dimming signal It is characterized by being a circuit, and by detecting and comparing the lamp voltage of the discharge lamp, it can be determined that the luminous flux of the discharge lamp has reached a predetermined luminous flux.

According to a third aspect of the present invention, in the second aspect of the present invention, the lamp voltage detection circuit includes a series-connected resistor for obtaining a divided voltage of the lamp voltage.
The lamp voltage can be easily detected.

According to a fourth aspect of the present invention, in the first aspect of the present invention, the dimming switching means interrupts / conducts a dimming signal input from the outside according to a rated starting condition and a dimming starting condition. The discharge lamp can be switched between a rated start condition and a dimming start condition.

According to a fifth aspect of the present invention, in the first aspect of the present invention, after dimming, the discharge lamp is lit by a predetermined power control, and stable dimming can be performed.

According to a sixth aspect of the present invention, in the first aspect of the present invention, in the power conversion section having a booster for boosting a voltage to a predetermined voltage, the booster comprises a boost chopper circuit. The power factor of the part can be improved.

According to a seventh aspect of the present invention, in the first aspect of the present invention, in the power conversion section having inverter means for supplying AC power to the discharge lamp, the inverter means inverts the polarity of the DC voltage to be input to the discharge lamp. , And a polarity inverting circuit for supplying the same to the discharge lamp, wherein a rectangular wave alternating voltage is applied to the discharge lamp, and a rectangular wave lighting with less flicker can be performed.

According to an eighth aspect of the present invention, in the power conversion section having the step-down means for stepping down to a predetermined voltage, the step-down means comprises a step-down chopper circuit including a switching element. The dimming of the discharge lamp can be controlled by controlling the switching of the switching element.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a circuit block diagram of a discharge lamp lighting device according to Embodiment 1 of the present invention. The AC power supply Vs is input to the power conversion unit P. The power conversion unit P is configured by a switching element or the like, controls dimming of the discharge lamp LA, and supplies lighting power for stably lighting the discharge lamp LA. .

The dimming switching means A includes a conversion circuit M for converting a dimming signal input from the outside into a dimming signal of the present lighting device.
A control circuit B for controlling switching of a switching element of the power conversion circuit P for stably lighting the discharge lamp LA with a predetermined dimming, and a luminous flux for determining that the discharge lamp LA has reached a predetermined luminous flux It is composed of a discriminating means C and the like.

Next, the operation of the first embodiment shown in FIG. 1 will be described. At the time of starting the dimming, that is, when the dimming signal is input or when the AC power supply Vs is supplied at the same time as the dimming signal is input, the discharge lamp LA starts. But,
In the first embodiment, the control circuit B invalidates the dimming signal and performs the rated starting until the discharge lamp LA reaches a light flux having a dimming ratio corresponding to the dimming signal.

After the luminous flux discriminating means C determines that the discharge lamp LA has reached a predetermined luminous flux, the control circuit B validates the dimming signal and becomes a luminous flux corresponding to the dimming signal. The power converter P is controlled as described above to light the discharge lamp LA with desired power.

Next, FIG. 3 shows a circuit block diagram using a lamp voltage detecting circuit as a light beam discriminating means for discriminating whether or not a predetermined light beam has been reached. The basic configuration is substantially the same as that of FIG. 1. The light beam discriminating means C in FIG. 1 is replaced by a lamp voltage detecting circuit D, and the input path of the dimming signal input from the outside to the conversion circuit M is turned on / off. Switch SW
1 is connected to the input of the conversion circuit M in series.
Since other configurations are the same as those in FIG. 1, the same components are denoted by the same reference numerals and description thereof will be omitted.

In general, the lamp voltage of a high-pressure discharge lamp at the time of starting is low, gradually increases as the operation shifts to stable lighting, and the luminous flux gradually increases as the lamp voltage increases. The lamp voltage detection circuit D includes resistors R1 and R2 connected to one end of the discharge lamp LA, a comparator COMP1, a reference voltage source Vref connected to an inverting input terminal of the comparator COMP1, and the like, and includes voltage dividing resistors R1 and R2. The lamp voltage of the discharge lamp LA is detected and the reference voltage source V
By comparing with the voltage of ref, it is determined that the luminous flux of the discharge lamp LA has reached a predetermined luminous flux.

The switch SW1 is connected to the comparator COMP.
Turns on / off according to the output of 1. Comparator COM
When the voltage of the non-inverting input terminal of P1 is lower than the voltage of the reference voltage source Vref, that is, when the luminous flux of the discharge lamp LA is smaller than a predetermined luminous flux, the output of the comparator COMP1 becomes L, the switch SW1 is turned off, and an external The dimming signal is cut off. When the voltage of the non-inverting input terminal of the comparator COMP1 is higher than the voltage of the reference voltage source Vref, that is, when the luminous flux of the discharge lamp LA is larger than a predetermined luminous flux, the output of the comparator COMP1 becomes H, the switch SW1 is turned ON and externally. Is input to the conversion circuit M.

Therefore, in the embodiment of FIG. 3, at the time of starting the dimming, the resistances R1 and R2 of the lamp voltage of the discharge lamp LA are changed.
When the divided voltage is lower than the voltage of the reference voltage Vref, that is, when the luminous flux of the discharge lamp LA is smaller than the luminous flux of the dimming ratio according to the dimming signal, the switch SW1 is turned off and the external dimming signal is converted. The control circuit B controls the power conversion unit P to turn on the discharge lamp LA in the fully lit state. As the operation shifts to stable lighting, the lamp voltage of the discharge lamp LA increases, and the resistances R1 and R2 of the lamp voltage of the discharge lamp LA increase.
Is higher than the voltage of the reference voltage Vref, that is, when the luminous flux of the discharge lamp LA is larger than the luminous flux of the dimming ratio according to the dimming signal, the switch SW1 is turned on to convert the dimming signal from the outside into the conversion circuit M. , And the control circuit B controls the power conversion unit P to turn on the discharge lamp LA with a desired power so that a light flux corresponding to the dimming signal is obtained, and a dimming state is set.

FIG. 2 shows a VI curve of the discharge lamp LA at the time of starting the dimming in the first embodiment.
Will be described. First, the discharge lamp LA immediately after lighting is shown in FIG.
Is lit at the position of P1 on the VI curve S1 corresponding to 100% lighting of. From there, the lighting gradually shifts to stable lighting on the VI curve S1, and along the VI curve S1 up to a point P2 corresponding to a predetermined luminous flux on the VI curve S1.
The lighting power of A increases. Thereafter, VI is applied at the point P2.
The curve shifts to the curve S2, reaches the point P3 corresponding to the desired light flux on the VI curve S2, and is turned on in the dimming state (50% dimming in FIG. 2).

The difference from the prior art can be expressed by comparing FIG. 7 and FIG. The hatched portions in FIGS. 7 and 2 represent the power consumption of the discharge lamp LA, and show that the first embodiment consumes less power than the conventional example by the difference in the area of the hatched lines.

Further, when the discharge lamp LA is started, the lamp is lit in the full lighting state, so that a sufficient lamp current flows and the life of the discharge lamp LA is not adversely affected.

(Embodiment 2) Embodiment 2 controls the lighting power of the discharge lamp LA at the time of dimming in the embodiment of FIG. 1. For example, by giving a constant power characteristic,
It is possible to extend the life of the discharge lamp LA and perform stable dimming lighting.

Third Embodiment As shown in FIG. 4, a third embodiment shows a specific circuit of the first embodiment. 4, the power converter P includes a rectifier DB, a step-up chopper circuit G, a smoothing capacitor C1, a step-down chopper circuit H, a filter circuit I, and a polarity inversion circuit J.

The boost chopper circuit G includes inductors L1 and F
The ETQ1, the diode D1, and the drive circuit F1 of the FET Q1 perform a boosting operation and a continuous charging current to the smoothing capacitor C1 for smoothing the output voltage of the boosting chopper circuit G, thereby improving the power factor.

The step-down chopper circuit H includes an FET Q2, a diode D2, an inductor L2, and a drive circuit F2 for the FET Q2. The filter circuit I includes a capacitor C2 and an inductor L3. And the control circuit B outputs the FET
A control signal is output to the drive circuit F2 of Q2.

The polarity inversion circuit J includes FETs Q3 to Q6, F
It is composed of drive circuits F3 of ETQ3 to ETQ6. The switching elements Q3, Q4, Q5, and Q6 are connected to a full bridge, and each of the switching elements Q3, Q6 and Q4, Q5 are driven by a drive signal from a drive circuit F3.
Are alternately turned on and off at a constant repetition frequency, alternately invert the polarity of the DC output voltage of the power converter P to output an alternating voltage, and supply alternating power having a frequency suitable for the discharge lamp LA. Performs rectangular wave lighting with little flicker.

The configuration and operation of the dimming switching means A are the same as those in FIG. Further, the operations of the rectifier DB and the filter circuit I will be omitted because they are well-known technologies.

In the third embodiment, the control circuit B of the dimming switching means A switches the FET Q2 via the drive circuit F2 according to the detection result of the lamp voltage detection circuit D and the dimming signal from the outside. By controlling, the output of the step-down chopper circuit H is controlled. By controlling the output of the step-down chopper circuit H, the lighting power supplied from the power converter P to the discharge lamp LA is controlled, and similarly to the first embodiment, the discharge lamp LA is controlled to a light flux corresponding to the dimming signal.

[0036]

According to the first aspect of the present invention, a power conversion unit for inputting AC power and supplying lighting power to a discharge lamp and a discharge lamp connected to an output of the power conversion unit are provided. In a discharge lamp lighting device for dimming a discharge lamp, the dimming is started under rated starting conditions at the time of starting dimming, and after the luminous flux of the discharge lamp and the luminous flux having a dimming ratio corresponding to the dimming signal substantially coincide with each other, the dimming is performed. It has dimming switching means for switching the rated starting condition to the dimming starting condition while maintaining the vicinity of the luminous flux of the dimming ratio according to the light signal, so that the dimming operation is performed without adversely affecting the lamp life. This has the effect of realizing energy saving.

According to a second aspect of the present invention, in the first aspect of the present invention, the luminous flux discriminating means for determining that the luminous flux of the discharge lamp and the luminous flux having a dimming ratio corresponding to the dimming signal substantially coincides with each other. Lamp voltage detection that compares the light flux of the discharge lamp with the light flux of the dimming ratio according to the dimming signal by comparing the reference voltage corresponding to the light flux with the dimming ratio according to the dimming signal Since the circuit is a circuit, it is possible to determine that the luminous flux of the discharge lamp has reached a predetermined luminous flux by detecting and comparing the lamp voltage of the discharge lamp.

According to a third aspect of the present invention, in the second aspect of the present invention, since the lamp voltage detecting circuit includes a series-connected resistor for obtaining a divided voltage of the lamp voltage, the lamp voltage can be easily detected. There is an effect that can be.

According to a fourth aspect of the present invention, in the first aspect of the invention, the dimming switching means interrupts / conducts a dimming signal input from the outside in accordance with a rated starting condition and a dimming starting condition. Therefore, there is an effect that the starting condition of the discharge lamp can be switched between the rated starting condition and the dimming starting condition.

According to a fifth aspect of the present invention, in the first aspect of the present invention, after the dimming, the discharge lamp is lit by a predetermined power control, so that there is an effect that stable dimming can be performed.

According to a sixth aspect of the present invention, in the first aspect of the present invention, in the power conversion section having a booster for boosting a voltage to a predetermined voltage, the booster comprises a boost chopper circuit. There is an effect that the power factor of the part can be improved.

According to a seventh aspect of the present invention, in the power conversion section having the inverter means for supplying AC power to the discharge lamp in the first invention, the inverter means inverts the polarity of the DC voltage to be input to the AC power supply. And outputs the same to the discharge lamp and applies a rectangular wave alternating voltage to the discharge lamp, which has the effect of enabling lighting of the rectangular wave with less flicker.

According to an eighth aspect of the present invention, in the first aspect of the present invention, in the power conversion section having step-down means for stepping down to a predetermined voltage, the step-down means comprises a step-down chopper circuit including a switching element. By controlling the switching of the switching element, there is an effect that the dimming of the discharge lamp can be controlled.

[Brief description of the drawings]

FIG. 1 is a circuit block diagram showing a first embodiment.

FIG. 2 is a graph of a VI curve of the lamp according to the first embodiment.

FIG. 3 is a circuit block diagram showing a first embodiment using a lamp voltage detection circuit.

FIG. 4 is a circuit block diagram showing a third embodiment.

FIG. 5 is a circuit block diagram showing a first conventional example.

FIG. 6 is a circuit block diagram showing a second conventional example.

FIG. 7 is a graph of a VI curve of a lamp in Conventional Example 2.

[Explanation of symbols]

 A dimming switching means B control circuit C luminous flux discriminating means LA discharge lamp M conversion circuit P power conversion unit Vs AC power supply

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3K072 AA14 BA05 BB10 CA16 GA02 GB18 GC04 HA03 HB05 3K073 AA12 AA52 BA01 BA28 CC13 CG16 CG44 CM07 3K098 CC01 CC40 DD06 DD22 EE17 FF03

Claims (8)

[Claims] 1. A power conversion unit for inputting AC power and supplying lighting power to a discharge lamp, and a discharge lamp connected to an output of the power conversion unit, wherein the power conversion unit dims the discharge lamp. In the electric light lighting device, the dimming is started under the rated starting condition at the time of the dimming start, and after the luminous flux of the discharge lamp substantially matches the luminous flux of the dimming ratio according to the dimming signal, the dimming according to the dimming signal is performed. A discharge lamp lighting device comprising: a dimming switching unit that switches a rated starting condition to a dimming starting condition while maintaining a ratio of light flux vicinity. 2. A light beam discriminating means for discriminating that a light beam of a discharge lamp substantially coincides with a light beam having a dimming ratio according to a dimming signal,
The lamp voltage is compared with a reference voltage corresponding to a luminous flux having a dimming ratio according to the dimming signal to determine that the luminous flux of the discharge lamp substantially matches the luminous flux having a dimming ratio according to the dimming signal. 2. The discharge lamp lighting device according to claim 1, wherein the discharge lamp lighting device is a lamp voltage detection circuit. 3. The discharge lamp lighting device according to claim 2, wherein the lamp voltage detection circuit includes a series-connected resistor for obtaining a divided voltage of the lamp voltage. 4. The light control device according to claim 1, wherein the light control switching means includes means for interrupting / conducting a light control signal input from the outside according to a rated start condition and a light control start condition. The discharge lamp lighting device as described in the above. 5. The discharge lamp lighting device according to claim 1, wherein after dimming, the discharge lamp is turned on by predetermined power control. 6. The discharge lamp lighting device according to claim 1, wherein in the power converter having a booster for boosting to a predetermined voltage, the booster comprises a boost chopper circuit. 7. The power converter having inverter means for supplying AC power to a discharge lamp, wherein the inverter means inverts the polarity of the input DC voltage to output an AC and supplies the AC power to the discharge lamp. The discharge lamp lighting device according to claim 1, wherein: 8. The discharge lamp lighting device according to claim 1, wherein in the power converter having step-down means for stepping down to a predetermined voltage, the step-down means comprises a step-down chopper circuit including a switching element.