JP2010287503A - Discharge lamp-lighting device and luminaire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a discharge lamp-lighting device capable of preventing a variation in an operating frequency in an AC output means for supplying AC output to a discharge lamp, and to provide a luminaire. <P>SOLUTION: The AC output is generated from an inverter circuit 21 based on the operating frequency corresponding to whole light lighting time and light dimming lighting time, and the discharge lamp 24 can be switched to whole light lighting and light dimming lighting. The discharge lamp-lighting device includes a feedback control means for controlling a lamp current of the discharge lamp 24 so as to approach a preset reference signal. Feedback control is invalidated in the whole light lighting time of the discharge lamp 24, and the feedback control is validated only in the light dimming lighting. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a discharge lamp lighting device and a lighting fixture for lighting a discharge lamp as a light source.

  Conventionally, as a discharge lamp lighting device for lighting a light source such as a discharge lamp, an inverter type device using an inverter circuit as an AC output means is known. In such a discharge lamp lighting device, the discharge lamp is lit at a constant brightness by controlling the switching cycle (operating frequency) of the switching elements constituting the inverter circuit according to the lighting state of the discharge lamp.

  On the other hand, in such a discharge lamp lighting device, as disclosed in Patent Document 1, the lamp power of a discharge lamp that is lit by high-frequency power from an inverter circuit is controlled so as to approach a preset reference value. Some have a feedback circuit that enables dimming control by changing the reference value at this time and changing the lamp power of the discharge lamp.

JP 2006-286261 A

  However, in such a configuration, for example, when the discharge lamp is switched from dimming lighting to all-light lighting, the operating frequency of the inverter circuit is increased until the control is stabilized due to delay of feedback control in the feedback circuit. For this reason, if the operating frequency fluctuates too much in the low direction, the discharge lamp may shine brightly for a moment, giving the user a sense of discomfort.

  Also, in the case of an abnormal mode such as lamp discharge, with the discharge lamp removed, the switching element constituting the inverter circuit may be advanced phase switching due to the feedback control delay of the feedback circuit, and stress is applied to the switching element, There was a risk of damage due to heat generation. That is, in this type of discharge lamp lighting device, the resonance frequency characteristic represented by the relationship between the frequency f and the lamp voltage V when the discharge lamp is fully lit is the characteristic shown in FIG. It is known that the characteristics shown in FIG. 4B can be obtained when there is no load due to lamp removal or the like. For this reason, for example, when the inverter circuit is operating at the all-lights lighting frequency fa, an abnormal mode such as lamp removal occurs, and the operating frequency fluctuates greatly due to feedback control delay in the feedback circuit. As shown in b), the inverter circuit may instantaneously operate at the phase advance side frequency fb (frequency lower than the resonance frequency fo). During this time, the switching element may be subjected to great stress and may be damaged. there were.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a discharge lamp lighting device and a lighting fixture that can prevent fluctuations in operating frequency in an AC output means for supplying an AC output to a discharge lamp. And

To solve the above problem,
The invention according to claim 1 is an AC output means for generating an AC output based on an operating frequency and supplying the AC output to the discharge lamp; and an all-light lighting frequency of the discharge lamp is set in the vicinity of a no-load resonance frequency of the AC output means A feedback control means for controlling the load output of the discharge lamp to approach a preset reference signal; an operating frequency of the AC output means in response to all-light lighting and dimming lighting of the discharge lamp Control means for invalidating the operation of the feedback control means when the discharge lamp is fully lit, and canceling the invalid operation of the feedback control means when the dimming light of the discharge lamp is lit. It is characterized by that. Here, constant current control or constant power control is suitable for feedback control by the feedback control means. In addition, in “invalidation of operation”, a feedback signal is not input by a software process that does not accept a feedback signal (not used for processing) in an IC chip or a microcomputer, or a switch element such as a mechanical / semiconductor element. It includes things like blocking connections.

  According to a second aspect of the present invention, in the first aspect of the invention, the control means includes delay means for controlling the load output of the discharge lamp to change gradually by switching between the all-light lighting and the dimming lighting. Furthermore, it is characterized by having.

  A third aspect of the present invention is an illumination fixture comprising: the discharge lamp lighting device according to the first or second aspect; and a fixture main body having the discharge lamp lighting device.

  According to the first aspect of the present invention, when the discharge lamp is switched to all-light lighting, it is possible to disable the feedback control and prevent the fluctuation of the operating frequency of the AC output means caused by the delay of the feedback control.

  Also, when the discharge lamp is fully lit, when the discharge lamp is removed, so-called lamp removal, feedback control is disabled and fluctuations in the operating frequency of the AC output means can be prevented. It is possible to prevent operation at the side frequency.

  According to the second aspect of the present invention, the transition of the discharge lamp from all-light lighting to dimming lighting can be performed while sequentially changing the lamp output, and the brightness of the discharge lamp is smoothly changed. be able to.

The perspective view which shows the lighting fixture with which the discharge lamp lighting device concerning the 1st Embodiment of this invention is applied. The figure which shows schematic structure of the discharge lamp inspection apparatus concerning 1st Embodiment. The figure which shows schematic structure of the light control part used for 1st Embodiment. The figure which shows the resonant frequency characteristic at the time of load of an inverter circuit, and the resonant frequency characteristic at the time of no load. The figure which shows schematic structure of the discharge lamp inspection apparatus concerning the 2nd Embodiment of this invention. The figure which shows schematic structure of the discharge lamp inspection apparatus concerning the 3rd Embodiment of this invention. The figure which shows the change of the lamp current at the time of switching from the all-light lighting of the discharge lamp of 3rd Embodiment to the light control lighting.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  First, the lighting fixture to which the lighting device of the present invention is applied will be briefly described. In FIG. 1, reference numeral 1 denotes an instrument body, which has a disk-shaped base 1a, and ring-shaped discharge lamps 2 and 3 having different diameters are arranged concentrically on the base 1a. A milky white shade 4 is attached to cover the discharge lamps 2 and 3. In addition, the discharge lamp lighting device 100 of the present invention is disposed inside the appliance body 1. Although not shown in the figure, it is a matter of course that a reflector, terminals, wirings and the like are also provided.

  FIG. 2 shows a schematic configuration of the discharge lamp lighting device 100 of the present invention incorporated in the fixture body 1 of the lighting fixture thus configured.

  In FIG. 2, 11 is an AC power source, and this AC power source 11 is a commercial power source (not shown). The AC power supply 11 is connected to an input terminal of a full-wave rectifier circuit 12. The full wave rectification circuit 12 generates an output obtained by full wave rectification of the AC power from the AC power supply 11.

  A boost chopper circuit 13 is connected to the full-wave rectifier circuit 12 as a power supply means. In this step-up chopper circuit 13, a series circuit of an inductor 14 constituting a step-up transformer and a field effect transistor 15 as a switching element is connected between the positive and negative output terminals of the full-wave rectifier circuit 12, and is parallel to the field effect transistor 15. An electrolytic capacitor 17 which is a smoothing capacitor is connected to a flywheel diode 16 having the polarity shown in FIG. A series circuit of resistors 18 and 19 is connected to both ends of the electrolytic capacitor 17 as voltage detecting means. The resistors 18 and 19 generate a divided voltage from the output of the electrolytic capacitor 17, and output the terminal voltage of the resistor 19 to the control unit 20. The field effect transistor 15 is turned on / off based on a comparison result between the terminal voltage of the resistor 19 and a reference voltage prepared in advance in the control unit 20. The inductor 14 generates a boosted output in the electrolytic capacitor 17 via the flywheel diode 16 by storing and releasing electromagnetic energy accompanying the on / off operation of the field effect transistor 15. The control unit 20 will be described later.

  An inverter circuit 21 is connected to the boost chopper circuit 13 as an AC output means. The inverter circuit 21 is configured as a so-called half-bridge type inverter circuit in which a series circuit of field effect transistors 221 and 222 as switching elements is connected in parallel with the electrolytic capacitor 17. The field effect transistors 221 and 222 have their gates connected to the control unit 20 and are controlled to be turned on / off by a control signal supplied from the control unit 20.

  A resonance circuit 23 is connected to the inverter circuit 21 as a resonance means. The resonance circuit 23 is connected to a series circuit of a resonance inductor 232 and a resonance capacitor 233 via a DC cut capacitor 231. In this case, the resonance inductor 232 and the resonance capacitor 233 set the all-light lighting frequency of the discharge lamp 24 determined by the resonance operation to a frequency fc in the vicinity of the no-load resonance frequency fo of the inverter circuit 21 shown in FIG. Is set.

  Connected to the resonance circuit 23 is a discharge lamp 24 (corresponding to the discharge lamps 2 and 3 shown in FIG. 1) as a light source. In this case, the connection point between the resonance inductor 232 and the resonance capacitor 233 of the resonance circuit 23 is connected to one filament 24 a of the discharge lamp 24, and the negative output of the full-wave rectifier circuit 12 of the resonance capacitor 233. A connection point with the terminal is connected to one filament 24 b of the discharge lamp 24. In addition, auxiliary windings 251 and 252 of a preheating transformer (not shown) are connected in series to the filaments 24a and 24b of the discharge lamp 24 so that the filaments 24a and 24b can be preheated.

  A current detection circuit 26 is connected to the discharge lamp 24 in series as load output detection means. The current detection circuit 26 includes a series circuit of a resistance element 27 connected in series to the discharge lamp 24 and a diode 28 of the illustrated polarity, and a diode 29 of the illustrated polarity connected in parallel to the series circuit. A flowing unidirectional lamp current is detected as a load output.

  The control unit 20 controls the entire power supply apparatus, and includes a chopper output control unit 201 as a power output control unit, an inverter control unit 202 as an operating frequency control unit, and a dimming control unit 203 as a dimming unit.

  The chopper output control unit 201 stores a reference voltage (not shown) in advance, and controls the on / off operation of the field effect transistor 15 based on the comparison result between the reference voltage and the terminal voltage of the resistor 19. A boosted output voltage is generated across the electrolytic capacitor 17 by the accumulation and release of electromagnetic energy in the inductor 14 accompanying the on / off operation.

  The inverter control unit 202 generates a control signal having an operating frequency of about several tens of kHz to 200 kHz based on the control signal output from the dimming control unit 203 to alternately turn on / off the field effect transistors 221 and 222 of the inverter circuit 21. Thus, a high-frequency AC output is generated between the drain and source of the field effect transistor 222.

  The dimming control unit 203 includes a reference signal generation unit 31 and a comparator 32 as shown in FIG. The reference signal generation unit 31 is a series circuit of resistors 33 and 34 to which one end is applied with a reference voltage (+5 V in the illustrated example), a collector connected to the other end of the series circuit as a switching means, and an NPN whose emitter is grounded And a dimming switching unit 36 is connected to the base of the NPN transistor 35. In this case, when the discharge lamp 14 is turned on, the dimming switching unit 36 turns off the NPN transistor 35 and generates a reference signal (reference voltage +5 V) for turning on the light at the connection point P between the resistors 33 and 34. At the time of dimming lighting, the NPN transistor 35 is turned on to generate a dimming lighting reference signal (<reference voltage + 5V) at the connection point P. The comparator 32 receives the reference signal generated by the reference signal generator 31 at one terminal and the lamp current detected by the current detection circuit 26 at the other terminal, and outputs the comparison result as a control signal. It constitutes a feedback control means. In this case, when the reference signal generation unit 31 receives the all-lighting reference signal (reference voltage + 5V), the comparator 32 maintains the output in the “H” level state and performs feedback control on the inverter control unit 202. When a reference signal for light control (<reference voltage + 5V) is applied from the reference signal generation unit 31 and the comparison result with the lamp current detected by the current detection circuit 26 is output as a control signal, the inverter control unit The invalidation of the feedback control to 202 is canceled to enable the feedback control. Further, when the feedback control is invalid, that is, when the output of the comparator 32 is maintained at the “H” level state, the inverter control unit 202 outputs a feedback signal (output from the comparator 32) in an IC chip or a microcomputer, for example. A software process that is not accepted (not used in the process) is executed, or the connection is interrupted so that a feedback signal is not input by a switch element such as a mechanical / semiconductor element, and the inverter circuit 21 is completely The operation frequency of the inverter circuit 21 is set so that the operation frequency is set to a constant operating frequency when the light is lit, and the feedback signal is received by the feedback control being enabled to bring the lamp current of the discharge lamp 24 closer to the reference signal for dimming lighting. To do.

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

  First, in the case of all light, in the reference signal generating unit 31, the dimming switching unit 36 turns off the NPN transistor 35, and the reference signal for lighting all light (reference voltage + 5V) is applied to the connection point P of the resistors 33 and 34. Is generated. Then, a reference signal for all light (reference voltage + 5V) is supplied from the reference signal generation unit 31 to the comparator 32, and the comparator 32 maintains its output in the “H” level state and provides feedback to the inverter control unit 202. Disable control.

  In this state, the AC power of the AC power supply 11 is full-wave rectified by the full-wave rectifier circuit 12 and supplied to the boost chopper circuit 13. In the step-up chopper circuit 13, the field effect transistor 15 is turned on / off based on a comparison result between the terminal voltage of the resistor 19 and a reference voltage prepared in advance in the chopper output control unit 201, and the field effect transistor 15 is turned on / off. Accompanied by the storage and release of electromagnetic energy of the inductor 14, a boosted output voltage is generated in the electrolytic capacitor 17 through the flywheel diode 16.

  The output voltage of the boost chopper circuit 13 is input to the inverter circuit 21. In the inverter circuit 21, the field effect transistors 221 and 222 are turned on / off by a control signal input from the inverter control unit 202, and high frequency alternating current is generated between the drain and source of the field effect transistor 222. In this case, the inverter control unit 202 is given an output that maintains the “H” level state from the reference signal generation unit 31 of the dimming control unit 203, and the feedback control is disabled. As a result, the inverter control unit 202 outputs a control signal corresponding to a constant operating frequency when all the lights are lit, and the inverter circuit 21 causes the field effect transistors 221 and 222 to operate at the operating frequency according to the control signal at this time. Turns on and off to generate high frequency alternating current.

  The high-frequency alternating current output from the inverter circuit 21 is given to the resonance circuit 23, and the resonance inductor 232 and the resonance capacitor 233 are resonantly operated. In this state, when a preheating current flows from the auxiliary windings 251 and 252 of a preheating transformer (not shown) to the filaments 24a and 24b of the discharge lamp 24, a predetermined starting voltage is applied between the filaments 24a and 24b of the discharge lamp 24. When applied, the discharge lamp 24 is fully lit (100%).

  Next, the dimming switching unit 36 turns on the NPN transistor 35 and generates a dimming reference signal (<reference voltage + 5 V) at the connection point P of the resistors 33 and 34. In this case, when a reference signal for dimming is supplied from the reference signal generator 31 to the comparator 32, the comparator 32 gives a comparison result between the reference signal at this time and the lamp current detected by the current detection circuit 26. It is output as a control signal and enables feedback control for the inverter control unit 202.

  In this state, when the AC power of the AC power supply 11 is full-wave rectified by the full-wave rectifier circuit 12 and supplied to the boost chopper circuit 13, an output voltage boosted by the boost chopper circuit 13 is generated as described above. Are input to the inverter circuit 21. The inverter circuit 21 turns on and off the field effect transistors 221 and 222 by a control signal input from the inverter control unit 202 to generate high-frequency alternating current. In this case, the inverter control unit 202 corresponds to the comparison result between the reference signal at the time of dimming lighting generated by the reference signal generation unit 31 of the dimming control unit 203 and the lamp current detected by the current detection circuit 26. Output is provided and feedback control is performed. As a result, the inverter circuit 21 causes the field effect transistors 221 and 222 to be turned on and off at an operating frequency corresponding to the control signal at this time to generate high-frequency alternating current, and the discharge lamp 24 is dimmed by the resonance operation of the resonance circuit 23. . In this case, since feedback control to the inverter control unit 202 is enabled, the lamp current of the discharge lamp 24 is controlled so as to always approach the reference signal for dimming lighting, and constant current control is performed.

  Therefore, in this way, an AC output is generated from the inverter circuit 21 on the basis of the operating frequency according to all-lighting and dimming lighting, and the discharge lamp 24 can be switched between all-lighting and dimming lighting. Therefore, it has a feedback control means for controlling the lamp current of the discharge lamp 24 to be close to a preset reference signal. When the discharge lamp 24 is fully lit, the feedback control is invalidated and only the dimming lighting is controlled. It was made valid. As a result, when the discharge lamp 24 is switched from dimming lighting to all-light lighting, the feedback control becomes invalid, so that it is possible to prevent fluctuations in the operating frequency of the inverter circuit due to delay of feedback control in the feedback circuit. It is possible to eliminate the uncomfortable feeling that the user feels when the discharge lamp 24 is brightened for a moment.

  In addition, when the discharge lamp 24 is turned on, feedback control can be disabled to prevent fluctuations in the operating frequency in the inverter circuit 21. Therefore, in the case of an abnormal mode such as so-called lamp removal, in which the discharge lamp 24 is removed. In addition, the inverter circuit 21 can be prevented from instantaneously operating at the phase advance side frequency, and the switching elements such as the field effect transistors 221 and 222 constituting the inverter circuit 21 can be prevented from being stressed. . As a result, the lighting frequency of the discharge lamp 24 determined by the resonance operation of the resonance circuit 23 can be set in the vicinity of the no-load resonance frequency of the inverter circuit 21, so that the operating frequency during the lighting of all light is as low as possible. However, the brightness of the discharge lamp 24 when all the lights are on can be maintained well.

  Furthermore, when the discharge lamp 24 is turned on all the time, the inverter circuit 21 is operated at a constant operating frequency, and the discharge lamp 24 is operated with a substantially constant current characteristic, so that the power of the discharge lamp 24 can be kept low. Accordingly, the input power can be reduced and an energy saving effect can be obtained. Furthermore, an unnecessary temperature rise of circuit elements used in the apparatus can be suppressed.

(Second Embodiment)
In the first embodiment, an example of constant current control is described in which the lamp current of the discharge lamp 24 is controlled to be constant with respect to the dimming reference signal generated by the reference signal generating unit 31 during the dimming operation. However, in the second embodiment, constant power control for controlling the output power of the discharge lamp 24 to be constant is used.

  FIG. 5 shows a schematic configuration of the second embodiment of the present invention, and the same parts as those in FIG. In this case, a power detection circuit 41 is connected in series with the field effect transistors 221 and 222 constituting the inverter circuit 21 as load output detection means. The power detection circuit 41 includes a resistance element 42 connected in series to the field effect transistors 221 and 222, and a series circuit of a resistance element 43 and a capacitor 44 connected in parallel to the resistance element 42. The voltage generated at the connection point of 44, that is, the voltage across the capacitor 44 is detected as the lamp power of the discharge lamp 24, and this detection output is input to one terminal of the comparator 32 of the reference signal generator 31.

  Others are the same as in FIG.

  Even in this case, in the case of all-optical operation, the reference signal generating unit 31 turns off the NPN transistor 35 by the dimming switching unit 36, and the reference signal for all light (reference) is connected to the connection point P of the resistors 33 and 34. By generating the voltage 5V) and disabling the feedback control to the inverter control unit 202, the inverter control unit 202 outputs a control signal corresponding to a constant operating frequency when all the lights are lit in the same manner as described above. In the inverter circuit 21, the field effect transistors 221 and 222 are turned on and off at the operating frequency according to the control signal, and the discharge lamp 24 is turned on in all light.

  On the other hand, in the case of the dimming operation, the dimming operation unit 36 turns on the NPN transistor 35 and generates a dimming reference signal (<reference voltage 5 V) at the connection point P of the resistors 33 and 34. In this case, when a reference signal for dimming is supplied from the reference signal generation unit 31 to the comparator 32, the comparator 32 compares the reference signal with the lamp power of the discharge lamp 24 detected by the power detection circuit 41. The result is output as a control signal, and feedback control to the inverter control unit 202 becomes effective. Thus, in the same manner as described above, the inverter control unit 202 causes the inverter circuit 21 to turn on and off the field effect transistors 221 and 222 at the operating frequency according to the control signal at this time, thereby generating high-frequency alternating current, and the resonance of the resonance circuit 23. The discharge lamp 24 is dimmed by operation. In this case, since feedback control to the inverter control unit 202 is enabled, the lamp power of the discharge lamp 24 is always controlled to be constant with respect to the dimming reference signal, and constant power control is performed.

  Therefore, even in this case, the same effect as that of the first embodiment can be obtained.

(Third embodiment)
The reference signal generation unit 31 of the dimming control unit 203 of the first embodiment immediately switches from all-light lighting to dimming lighting when the NPN transistor 35 is turned on from the off state by the dimming switching unit 36. However, in the third embodiment, the mode is gradually switched from full light lighting to dimming lighting.

  In the third embodiment, the schematic configuration diagram of the discharge lamp lighting device shown in FIG. 5 is used, and only the schematic configuration of the dimming control unit is shown in FIG. In FIG. 6, the same parts as those in FIG.

  In this case, a capacitor 51 is connected as a delay means in parallel with the NPN transistor 35. This capacitor 51 delays the operation time from turning on to off of the NPN transistor 35 when switching from all light to dimming.

  Others are the same as FIG.

  Even in this case, if the NPN transistor 35 is turned off by the dimming switching unit 36 of the reference signal generation unit 31 as in the second embodiment, the feedback control to the inverter control unit 202 becomes invalid. When the discharge lamp 24 is turned on all the time, and the NPN transistor 35 is turned on, feedback control to the inverter control unit 202 becomes effective, and the lamp power of the discharge lamp 24 becomes a reference signal for dimming lighting. On the other hand, it is always controlled to be constant (constant power control).

  In this case, during all light, the capacitor 51 is charged while the NPN transistor 35 is off. Then, in order to switch from all-light lighting to dimming lighting, when the NPN transistor 35 is turned on from the off state by the dimming switching unit 36, the NPN transistor 35 is turned off over time due to the discharge of the charge of the capacitor 51. Switch on. Thereby, the reference signal generated at the connection point P of the resistors 33 and 34 also changes from the reference signal for all-light lighting (reference voltage +5 V) to the reference signal for dimming lighting (<reference voltage +5 V) over time. Therefore, the inverter control unit 202 controls the operating frequency of the inverter circuit 21 so that the lamp power of the discharge lamp 24 becomes constant with respect to the reference signal by the feedback control described above, and the lamp current of the discharge lamp 24 is As shown in FIG. 7, the time is gradually changed from the all-light lighting period A to the dimming lighting period B over time.

  Even if it does in this way, the effect similar to 1st Embodiment can be acquired, and also the transition from the all-light lighting of the discharge lamp 24 to dimming lighting can be performed, changing lamp electric power over time. Therefore, the brightness of the discharge lamp 24 can be changed smoothly.

  In the third embodiment, the case of constant power control in which the lamp power of the discharge lamp 24 is controlled to be constant has been described. However, the lamp current of the discharge lamp 24 is controlled to be constant as in the first embodiment. Constant current control can also be applied. In this case, the current detection circuit 26 described with reference to FIG. Further, if the signal given to the NPN transistor 35 from the dimming switching unit 36 instead of the capacitor 51 is a PWM signal, the ON / OFF time ratio of the NPN transistor 35 can be arbitrarily changed.

  In addition, this invention is not limited to the said embodiment, In the implementation stage, it can change variously in the range which does not change the summary.

  Furthermore, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, even if some constituent requirements are deleted from all the constituent requirements shown in the embodiment, the problem described in the column of the problem to be solved by the invention can be solved, and is described in the column of the effect of the invention. If the above effect is obtained, a configuration from which this configuration requirement is deleted can be extracted as an invention.

DESCRIPTION OF SYMBOLS 1 ... Appliance main body 2.3 ... Discharge lamp 4 ... Sade, 11 ... AC power supply, 100 ... Discharge lamp lighting device 12 ... Full wave rectifier circuit, 13 ... Boost chopper circuit 14 ... Inductor, 15 ... Field effect transistor 20 ... Control DESCRIPTION OF SYMBOLS 201: Chopper output control part 202 ... Inverter control part 203 ... Dimming control part 21 ... Inverter circuit 23 ... Resonance circuit 232 ... Resonance inductor 233 ... Resonance capacitor 24 ... Discharge lamp, 26 ... Current detection circuit DESCRIPTION OF SYMBOLS 31 ... Reference signal production | generation part, 32 ... Comparator 35 ... NPN-type transistor, 36 ... Dimming switching part, 41 ... Power detection circuit 51 ... Capacitor

Claims (3)

AC output means for generating an AC output based on the operating frequency and supplying it to the discharge lamp;
Resonance means for setting the lighting frequency of the discharge lamp at the time of all light in the vicinity of a no-load resonance frequency of the AC output means;
Feedback control means for controlling the load output of the discharge lamp to approach a preset reference signal;
The operation frequency of the AC output means is controlled according to the all-light lighting and the dimming lighting of the discharge lamp, and the operation of the feedback control means is invalidated when the discharge lamp is all-lighted, and the discharge lamp is adjusted. Control means for releasing operation invalidity of the feedback control means when the light is turned on;
A discharge lamp lighting device comprising: 2. The discharge lamp lighting device according to claim 1, wherein the control means further comprises delay means for controlling the load output of the discharge lamp to change gradually by switching between the all-light lighting and the dimming lighting. . 3. A lighting fixture comprising: the discharge lamp lighting device according to claim 1; and a fixture body having the discharge lamp lighting device.

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