JP2009004300A - High pressure discharge lamp lighting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high pressure discharge lamp lighting device capable of satisfying (1) non-load voltage: 3.5-5.0 kVp, (2) integration pulse: 100 μs/s(2.7 kV) or more even if the output wiring length is 2 m or more. <P>SOLUTION: The high pressure discharge lamp lighting device has a step-up transformer 8 in which a secondary coil 8b is inserted in a load circuit, a two-terminal thyristor 13 which is connected to a primary coil 8a side of the step-up transformer 8, and a charge and discharge circuit provided between outputs of a DC power supply circuit, and is provided with an ignitor starting circuit which generates a high voltage pulse to the secondary coil 8b of the step-up transformer 8 when the two-terminal thyristor 13 is conducted. The ratio of winding (secondary coil/primary coil) of the step-up transformer 8 is established so that the secondary coil voltage may be nearly 4.3 kV. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a high pressure discharge lamp lighting device that controls lighting of a high pressure discharge lamp such as a high pressure mercury lamp, a high pressure sodium lamp, or a metal halide lamp.

  The conventional high pressure discharge lamp lighting device includes an igniter start circuit for generating a pulse voltage for starting and lighting the high pressure discharge lamp. This igniter starting circuit is provided with a high-voltage transformer whose secondary winding is inserted between the high-pressure discharge lamp and the inductor, and one end of the primary winding of the high-voltage transformer, and is charged by the current from the chopper circuit. Charge / discharge circuit, the other charge / discharge circuit charged by the current flowing through the inductor when one of the pair of FETs is turned on, and the three terminals connected to the other end of the primary winding of the high-voltage transformer The thyristor is connected to the gate of this three-terminal thyristor, and is turned on when the charging voltage of the other charging / discharging circuit reaches the breakover voltage, turning on the three-terminal thyristor, and increasing the charging voltage of one charging / discharging circuit. And a two-terminal thyristor to be applied to the primary winding of the transformer (see, for example, Patent Document 1).

In order to start a high pressure discharge lamp such as a ceramic metal halide lamp, an igniter starting circuit is required as described above. However, due to the demand for downsizing of a high pressure discharge lamp lighting device in the market, downsizing of the igniter starting circuit is also required. ing.
JP-A-2005-203185 (6th page, FIG. 7)

  In the conventional high pressure discharge lamp lighting device described above, two types of thyristors and two charge / discharge circuits are used in the igniter start circuit to generate or stop a high voltage pulse for starting and lighting the high pressure discharge lamp. The circuit configuration was complicated.

In addition, as a standard for lighting high pressure discharge lamps such as ceramic metal halide lamps,
(1) No-load voltage: 3.5 to 5.0 kVp
(2) Integrated pulse: There are two conditions of 100 μs / s (2.7 kV) or more,
(3) In the case of indoor models, the market demand is that the output wiring length can be lit even if it is 2 m or longer.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a high-pressure discharge lamp lighting device having a simple circuit configuration and a small igniter starting circuit.

Also, even if the output wiring length is 2m or more,
(1) No-load voltage: 3.5 to 5.0 kVp
(2) An object of the present invention is to provide a high pressure discharge lamp lighting device capable of satisfying an accumulated pulse of 100 μs / s (2.7 kV) or more.

  A high pressure discharge lamp lighting device according to the present invention includes a load circuit to which a high pressure discharge lamp is attached, a DC power supply circuit for converting a commercial power supply into a desired DC voltage, and a DC voltage from the DC power supply circuit is converted into an AC voltage. Provided between the inverter circuit to be supplied to the load circuit, the step-up transformer in which the secondary winding is inserted in the load circuit, the two-terminal thyristor connected to the primary winding side of the step-up transformer, and the output of the DC power supply circuit An igniter starting circuit for generating a high voltage pulse in the secondary winding of the step-up transformer when the two-terminal thyristor is turned on, and a charging / discharging circuit for starting the high-pressure discharge lamp of the load circuit After the high-pressure discharge lamp is lit, the DC power supply circuit is set so that the charging voltage becomes a voltage value that makes the two-terminal thyristor non-conductive after the high-voltage discharge lamp is turned on. And a control unit for controlling, the winding ratio of the step-up transformer (2 windings / primary windings), secondary winding voltage and sets to be substantially 4.3KV.

  In the present invention, when starting the high-pressure discharge lamp of the load circuit, after the high-pressure discharge lamp is lit so that the charging voltage of the charging / discharging circuit becomes a voltage value for conducting the two-terminal thyristor, the charging voltage is 2 Since the DC power supply circuit is controlled so that the voltage value that makes the terminal thyristor non-conductive, the charge / discharge circuit and the two-terminal thyristor are each one component, which makes the configuration of the igniter start circuit simple. There is an effect that the size can be reduced. Further, by selecting the turn ratio of the step-up transformer 8 so that the secondary winding voltage VL2 is approximately 4.3 kVp, the attenuation amount of the secondary winding voltage VL2 is reduced even when the output wiring length is 2 m or more. be able to.

Embodiment 1 FIG.
FIG. 1 is a circuit diagram showing a configuration of a high pressure discharge lamp lighting device according to Embodiment 1 of the present invention.
The high pressure discharge lamp lighting device of the present embodiment shown in the figure includes a DC power supply circuit 1, a half-bridge type inverter circuit, a load circuit, an igniter starting circuit, and a control circuit 14. The DC power supply circuit 1 includes, for example, a rectifier circuit that rectifies the power of the AC power supply into DC power, and a step-up PFC (Power Factor Control) circuit connected between outputs of the rectifier circuit. This step-up PFC circuit is provided with an inductor, a switching element for stepping up the output of the rectifier circuit based on on / off control of the control circuit 14 and the like.

  The inverter circuit includes a first switching element 2 and a second switching element 3 connected in series between outputs of the DC power supply circuit 1, and the first switching element 2 and the second switching element 3 in parallel. And a series circuit of a first electrolytic capacitor 4 and a second electrolytic capacitor 5. The load circuit includes a secondary of a step-up transformer 8 described later between a connection point of the first switching element 2 and the second switching element 3 and a connection point of the first electrolytic capacitor 4 and the second electrolytic capacitor 5. The inductor 6 and the high-pressure discharge lamp 9 are connected in series via the winding 8b, and the capacitor 7 is connected in parallel to the high-pressure discharge lamp 9 and the secondary winding 8b. As the high-pressure discharge lamp 9 described above, an HID lamp (high-pressure mercury lamp), a high-pressure sodium lamp, a metal halide lamp, or the like is used.

  In the igniter starting circuit, the resistor 10, the diode 11 and the charge / discharge capacitor 12 connected in series between the outputs of the DC power supply circuit 1 and the secondary winding 8b are inserted between the inductor 6 and the high pressure discharge lamp 9 as described above. And between the other end of the primary winding of the step-up transformer 8 and the negative electrode side of the charge / discharge capacitor 12. One end of the primary winding 8 a is connected to the connection point of the diode 11 and the charge / discharge capacitor 12. And a two-terminal thyristor 13 inserted into the. A charge / discharge circuit is configured by the resistor 10, the diode 11, and the charge / discharge capacitor 12 described above.

  The control circuit 14 will be described in detail when explaining the operation. When starting the high-pressure discharge lamp 9 of the load circuit, the control circuit 14 sets the voltage value at which the charging voltage of the charging / discharging circuit makes the two-terminal thyristor 13 conductive, that is, the breakover of the two-terminal thyristor 13. After the DC power supply circuit 1 is controlled to reach a voltage value that reaches the voltage and the high-pressure discharge lamp 9 is lit, the charging voltage is a voltage value that makes the two-terminal thyristor 13 non-conductive (a voltage value lower than the breakover voltage). The DC power supply circuit 1 is controlled so that The determination as to whether or not the high-pressure discharge lamp 9 is lit is not shown in FIG. 1, but for example, when the voltage of the high-pressure discharge lamp 9 detected by the voltage detection circuit becomes lower than a preset voltage value. Then, it is determined that the high pressure discharge lamp 9 has been turned on. Instead of this, it may be determined whether or not the high-pressure discharge lamp 9 has been lit based on the current detected by the current detection circuit. In this case, when the detected current becomes higher than a preset current value, it is determined that the high pressure discharge lamp 9 has been turned on.

Next, the operation of the high pressure discharge lamp lighting device of the present embodiment will be described.
When starting the high-pressure discharge lamp 9, the control circuit 14 alternately turns on and off the first switching element 2 and the second switching element 3, controls the DC power supply circuit 1, and the voltage detection circuit. It is determined whether or not the high pressure discharge lamp 9 has been turned on through the detection voltage. The first switching element 2 and the second switching element 3 are controlled by turning on / off only the first switching element 2 at a high frequency for a preset first period, and then for a second period, Only the switching element 3 is turned on / off at a high frequency, and the switching between the first and second periods is repeated at a low frequency. The control on the DC power supply circuit 1 side is performed so that the voltage charged to the charge / discharge capacitor 12 via the resistor 10 and the diode 11 reaches a voltage value that reaches the breakover voltage of the two-terminal thyristor 13.

  By this control, the charging voltage of the charging / discharging capacitor 12 is discharged every time it reaches the breakover voltage of the two-terminal thyristor 13, and the voltage is intermittently applied to the primary winding 8 a of the step-up transformer 8. A high voltage pulse is generated in 8 b, superimposed on a rectangular wave voltage having a lighting frequency by the operation of the first switching element 2 and the second switching element 3, and repeatedly applied to the high-pressure discharge lamp 9. On the other hand, when the control circuit 14 generates a high voltage pulse in the secondary winding 8b of the step-up transformer 8, and detects that the detection voltage of the voltage detection circuit is lower than a preset voltage value, It is determined that the high-pressure discharge lamp 9 has been turned on, and the DC power supply circuit 1 is controlled so that the charging voltage of the charging / discharging capacitor 12 is lower than the breakover voltage of the two-terminal thyristor 13, and the secondary winding 8 b of the step-up transformer 8. The high-voltage pulse generated in is stopped.

  As described above, according to the first embodiment, when starting the high-pressure discharge lamp 9 of the load circuit, the DC power supply is set so that the charging voltage of the charging / discharging capacitor 12 reaches a voltage value that reaches the breakover voltage of the two-terminal thyristor 13. After the circuit 1 is controlled and the high-pressure discharge lamp 9 is lit, the DC power supply circuit 1 is controlled so that the charging voltage is lower than the breakover voltage of the two-terminal thyristor 13. Since the circuit and the two-terminal thyristor 13 are each one component, the configuration of the igniter starting circuit is simplified and the size can be reduced.

Embodiment 2. FIG.
FIG. 2 is a circuit diagram showing a configuration of a high pressure discharge lamp lighting device according to Embodiment 2 of the present invention. In addition, the same code | symbol is attached | subjected to the same or equivalent part as Embodiment 1 demonstrated in FIG. 1, and description is abbreviate | omitted.
In the first embodiment, a charging / discharging circuit in which a resistor 10, a diode 11, and a charging / discharging capacitor 12 are connected in series is provided between the outputs of the DC power supply circuit 1. However, in the present embodiment, the inductor 6 and the A charging / discharging circuit in which a resistor 10, a diode 11, and a charging / discharging capacitor 12 are connected in series between a connection point of the secondary winding 8b of the step-up transformer 8 and the negative electrode side (ground side) of the DC power supply circuit 1. It is provided.

  Similarly to the first embodiment, the two-terminal thyristor 13 of the igniter starting circuit in the present embodiment is connected to the charge / discharge capacitor 12 via the primary winding 8a of the step-up transformer 8, and at the time of starting the high-pressure discharge lamp 9 having a characteristic that the breakover voltage is lower than the voltage applied to 9 and the breakover voltage is higher than the voltage after the high-pressure discharge lamp 9 is lit. When starting the high-pressure discharge lamp 9, the control circuit 14 first turns on and off only the first switching element 2 at a high frequency for the first period, and then the second During this period, only the second switching element 3 is turned on / off at a high frequency, and this switching is repeated at a low frequency.

Next, the operation of the high pressure discharge lamp lighting device of the present embodiment will be described.
When starting the high pressure discharge lamp 9 of the load circuit, the control circuit 14 turns on and off only the first switching element 2 at a high frequency in the first period, and then in the second period, Only the second switching element 3 is turned on / off at a high frequency, and this switching is repeated at a low frequency. When the first switching element is on / off, the current flowing through the inductor 6 is charged into the charge / discharge capacitor 12, and when the charge voltage reaches the breakover voltage of the two-terminal thyristor 13, The charging voltage is discharged and applied to the primary winding 8a of the step-up transformer 8, a high voltage pulse is generated in the secondary winding 8b, and the lighting frequency due to the operation of the first and second switching elements 2 and 3 is increased. The voltage is applied to the high-pressure discharge lamp 9 while being superimposed on the rectangular wave voltage.

  On the other hand, when the high-pressure discharge lamp 9 is lit by application of a high voltage pulse, the control circuit 14 alternately turns on and off the first and second switching elements 2 and 3 at a high frequency, and continues lighting the high-pressure discharge lamp 9. To do. At this time, since the voltage applied to the high-pressure discharge lamp 9 decreases, the charging voltage of the charging / discharging capacitor 12 becomes lower than the breakover voltage of the two-terminal thyristor 13, and the high voltage generated in the secondary winding 8 b of the step-up transformer 8. Stop the voltage pulse. Note that the lighting determination of the high-pressure discharge lamp 9 by the control circuit 14 is when it is detected that the detection voltage of the voltage detection circuit has become lower than a preset voltage value.

  As described above, according to the second embodiment, when the high-pressure discharge lamp 9 is started, the secondary winding 8b of the step-up transformer 8 every time the charging voltage to the charge / discharge capacitor 12 reaches the breakover voltage of the two-terminal thyristor 13. When a high voltage pulse is generated and the high pressure discharge lamp 9 is turned on, the charge voltage to the charge / discharge capacitor 12 becomes lower than the breakover voltage of the two-terminal thyristor 13 and is applied to the secondary winding 8b of the step-up transformer 8. Since the generated high voltage pulse stops, it becomes unnecessary to control the change of the output voltage of the DC power supply circuit 1 when the high pressure discharge lamp 9 is turned on. For this reason, the igniter start circuit can be simplified and miniaturized. In addition, the configuration of the control circuit 14 can be simplified as compared with the first embodiment.

Embodiment 3 FIG.
As already mentioned, as a standard for lighting high pressure discharge lamps such as ceramic metal halide lamps,
(1) No-load voltage: 3.5 to 5.0 kVp
(2) Integrated pulse: There are two conditions of 100 μs / s (2.7 kV) or more,
(3) In the case of indoor models, the market demand is that the output wiring length can be lit even if it is 2 m or longer.
In the third and subsequent embodiments, the optimum values of the constants of the igniter starting circuit for solving this problem have been studied.

  First, in the present embodiment, the turn ratio of the step-up transformer 8 is examined. The secondary winding voltage VL2 was measured by changing the turn ratio of the step-up transformer 8 and changing the load capacitance Cc as the stray capacitance depending on the output wiring length.

  3 and 4 are diagrams showing the third embodiment. FIG. 3 is a circuit diagram showing an igniter starting circuit. FIG. 4 is a secondary winding when the turn ratio of the step-up transformer 8 and the load capacitance Cc are changed. It is a figure which shows the measurement result of voltage VL2.

  As shown in FIG. 3, a load capacitance Cc is connected in parallel to the secondary winding 8b and the capacitor 7 of the step-up transformer 8, and the secondary winding voltage VL2 (the terminal of the load capacitance Cc, for example, at a power supply voltage Vi = 470 VDC). Voltage). At this time, the voltage of the charge / discharge capacitor 12 is 430 VDC.

  The measurement result of the secondary winding voltage VL2 is shown in FIG. The load capacitance Cc = 100 pF corresponds to the output wiring length 1 m, and the load capacitance Cc = 200 pF corresponds to the output wiring length 2 m.

  As shown in FIG. 4, at the load capacitance Cc = 0 pF, when the turn ratio (N2 / N1) of the step-up transformer 8 decreases, the secondary winding voltage VL2 tends to decrease. However, even if the load capacitance Cc increases to 100 pF and 200 pF, the attenuation amount of the secondary winding voltage VL2 decreases. From this result, even when the output wiring length is 2 m or more, the turn ratio of the step-up transformer 8 that satisfies the conditions of the no-load voltage and the integrated pulse is 8-10 when Vi = 470 VDC (the voltage of the charge / discharge capacitor 12 is 430 VDC). preferable. The turn ratio of the step-up transformer 8 is 12 or less.

  The winding ratio (N2 / N1) of the step-up transformer 8 is selected so that the secondary winding voltage VL2 is about 4.3 kVp, which is the center value of the standard (3.5 to 5 kVp), thereby making the load capacitance Cc Even if the current increases to 100 pF and 200 pF, the attenuation amount of the secondary winding voltage VL2 can be reduced.

Embodiment 4 FIG.
Next, the effect of adding an inductance L3 between the primary winding 8a of the step-up transformer 8 and the two-terminal thyristor 13 was examined.

  5 and 6 are diagrams showing the fourth embodiment. FIG. 5 is a circuit diagram showing an igniter starting circuit. FIG. 6 is a diagram showing a load capacitance Cc and a secondary winding voltage VL2 and 2.7 kV when an inductance L3 is added. It is a figure which shows the relationship with an integration pulse.

  As shown in FIG. 5, an inductance L3 is added between the primary winding 8a of the step-up transformer 8 and the two-terminal thyristor 13, and the secondary winding voltage VL2 (the terminal of the load capacitance Cc) at the power supply voltage Vi = 470 VDC. Voltage), a 2.7 kV pulse width, and a 2.7 kV integrated pulse were measured.

  The inductance L3 was measured for 47 μH, 39 μH, 33 μH, and 0 μH. The load capacitance Cc was measured for 0 pF, 200 pF (corresponding to an output wiring length of 2 m), 470 pF (corresponding to an output wiring length of 4.7 m), and 1000 pF (corresponding to an output wiring length of 10 m).

  The result is shown in FIG. When the inductance L3 is added, the secondary winding voltage VL2 pulse vibrates finely. When the inductance L3 increases, the height of the secondary winding voltage VL2 attenuates. In the experiment, the primary winding was increased / decreased so that the height of the secondary winding voltage VL2 became constant even when the inductance L3 increased. As a result, the number of turns of the primary winding 8a is N1 = 13 [T], the number of turns of the secondary winding 8b is N2 = 140 [T], the turn ratio is N2 / N1 = 10.7, and the inductance is L3 = 47 [μH]. Even when the load capacitance Cc = 200 [pF] is attached, the 2.7 kV integrated pulse greatly exceeds the standard 100 [μs / s], so that it is selected as the optimum value.

  The one with the inductance L3 satisfies the standard with the secondary winding voltage VL2 of about 4 kVp even if the load capacitance Cc = 200 [pF] is attached, and 100 [μs / s even if the 2.7 kV integrated pulse is low. ] Before and after. With the inductance L3, the 2.7 kV integrated pulse is improved when the load capacitance Cc = 200 [pF] is attached, compared with the one without the inductance L3.

  In particular, when L3 = 47 μH (the turn ratio of the step-up transformer 8 = 10.7), the 2.7 kV integrated pulse when the load capacitance Cc = 200 [pF] is added is improved.

  Increasing the inductance L3 from 47 μH improves the 2.7 kV integrated pulse. However, when the inductance L3 exceeds 100 μH, the height of the secondary winding voltage VL2 decreases to 4 kVp or less. Accordingly, the inductance L3 is preferably in a range of 47 to 100 μH.

  In this way, by adding the inductance L3 between the primary winding 8a of the step-up transformer 8 and the two-terminal thyristor 13, the 2.7 kV integrated pulse with the load capacitance Cc can be improved. .

  Furthermore, by setting the inductance L3 to 47 to 100 μH, the 2.7 kV integrated pulse when the load capacitance Cc = 200 [pF] is attached can be significantly improved.

Embodiment 5. FIG.
Next, the resistance 10 of the igniter starting circuit was examined.

  7 to 10 are diagrams showing the fifth embodiment, FIG. 7 is a circuit diagram showing an igniter starting circuit, and FIG. 8 is a diagram showing the secondary winding voltage VL2, 2. when the resistance value of the resistor 10 is changed. FIG. 9 is a circuit diagram showing an igniter starting circuit to which an inductance L3 is added, FIG. 10 is a secondary winding when the resistance value of the resistor 10 is changed in the circuit of FIG. It is a figure which shows the measurement results, such as line voltage VL2, 2.7 kV integration pulse.

  As shown in FIG. 7, for example, at the power supply voltage Vi = 470 VDC (the voltage of the charge / discharge capacitor 12 is 430 VDC), the primary winding voltage VL1 and the secondary winding voltage VL2 of the step-up transformer 8 when the resistor 10 is changed. A 2.7 kV integrated pulse or the like was measured.

  The result is shown in FIG.

  When the resistance 10 is 13.6 kΩ, the temperature of the resistance 10 rises to about 100 ° C. Since the substrate on which the resistor 10 is mounted cannot withstand this temperature (about 100 ° C.), it is impossible for the resistor 10 to have 13.6 kΩ.

  When the resistance 10 is 20 kΩ, the temperature of the resistance 10 drops to about 70 ° C., and the substrate can withstand this temperature. The secondary winding voltage VL2 satisfies the standard. The 2.7 kV integrated pulse is just below the standard.

  Further, when the resistance 10 is 36 kΩ, the temperature of the resistance 10 falls to about 52 ° C. The secondary winding voltage VL2 satisfies the standard, but the 2.7 kV integrated pulse is significantly lower than the standard and the resistance 10 is 36 kΩ, which is not possible.

  Thus, it can be said that the resistance 10 of the igniter starting circuit is preferably about 20 kΩ in the case of the circuit of FIG. 7, but the 2.7 kV integrated pulse is slightly below the standard.

  Therefore, as shown in FIG. 9, when the inductance L3 is added between the primary winding 8a of the step-up transformer 8 and the two-terminal thyristor 13, and the resistance value of the resistor 10 is changed at the power supply voltage Vi = 514 VDC. The secondary winding voltage VL2 (voltage between terminals of the load capacitance Cc), 2.7 kV pulse width, 2.7 kV integrated pulse, and the like were measured. The results are shown in FIG.

  As shown in FIG. 10, when the resistance value of the resistor 10 is 13.6 kΩ, the surface temperature of the resistor 10 (90 seconds after igniter firing) rises to about 122 ° C. Since the substrate on which the resistor 10 is mounted cannot withstand this temperature (about 122 ° C.), the resistor 10 with 13.6 kΩ is not possible.

  When the resistance value of the resistor 10 is 20 kΩ, the surface temperature of the resistor 10 (after igniter firing 90 seconds) is about 95 ° C., which is within the allowable range. Even if the load capacitance is increased to 200 pF and 470 pF, the secondary winding voltage VL2 and the 2.7 kV integrated pulse satisfy the standard.

  When the resistance value of the resistor 10 is 36 kΩ, the surface temperature of the resistor 10 (after 90 seconds of igniter firing) is about 59 ° C. and further decreases. However, the 2.7 kV integrated pulse does not satisfy the standard even when the load capacity is 0 pF.

  As described above, if the inductance L3 is added between the primary winding 8a of the step-up transformer 8 and the two-terminal thyristor 13 and the resistance value of the resistor 10 is set to about 20 kΩ, the load capacitance becomes 200 pF or more. The secondary winding voltage VL2, 2.7 kV integrated pulse satisfies the standard.

Embodiment 6 FIG.
Next, the optimum value of the charge / discharge capacitor 12 of the igniter starting circuit was examined with a circuit to which an inductance L3 was added.

  FIGS. 11 and 12 are diagrams showing the sixth embodiment. FIG. 11 is a circuit diagram showing an igniter starting circuit. FIG. 12 shows a case where the capacitance of the charge / discharge capacitor 12 is changed and load capacitance is added at each capacitance value. It is a figure which shows the result of having measured secondary winding voltage VL2, 2.7 kV integrated pulse, etc. FIG.

  In the igniter starting circuit shown in FIG. 11, measurement was performed with the resistor 10 of 24 kΩ, the step-up transformer 8 turns ratio of 10.7, and the inductance L3 of 82 μH.

  The capacity of the charge / discharge capacitor 12 was measured for 0.056 μF, 0.1 μF, 0.22 μF, 0.47 μF, and 1 μF. As shown in FIG. 12, when the capacitance of the charge / discharge capacitor 12 is 0.22 μF or more, the 2.7 kV integrated pulse does not satisfy the standard. Further, when the capacity of the charge / discharge capacitor 12 is 0.056 μF, VL2 tends to decrease particularly when a load capacity is added, but the load capacity is within an allowable range up to 200 pF. A capacitance of 0.1 μF of the charge / discharge capacitor 12 shows the best characteristics.

  As described above, the optimum value of the charge / discharge capacitor 12 of the igniter starting circuit to which the inductance L3 is added is 0.1 μF, but there is no practical problem if it is in the range of 0.1 ± 0.05 μF.

It is a circuit diagram which shows the structure of the high pressure discharge lamp lighting device which concerns on Embodiment 1 of this invention. It is a circuit diagram which shows the structure of the high pressure discharge lamp lighting device which concerns on Embodiment 2 of this invention. FIG. 6 is a diagram illustrating the third embodiment and is a circuit diagram illustrating an igniter starting circuit. FIG. 10 is a diagram illustrating the third embodiment, and is a diagram illustrating measurement results of the secondary winding voltage VL2 when the turn ratio of the step-up transformer 8 and the load capacitance Cc are changed. FIG. 10 is a diagram illustrating the fourth embodiment and is a circuit diagram illustrating an igniter starting circuit. The figure which shows Embodiment 4 and shows the relationship between the load capacity Cc at the time of adding the inductance L3, the secondary winding voltage VL2, and a 2.7 kV integrated pulse. FIG. 10 is a diagram illustrating the fifth embodiment and is a circuit diagram illustrating an igniter starting circuit. FIG. 10 is a diagram illustrating the fifth embodiment, and illustrates measurement results of the secondary winding voltage VL2, 2.7 kV integrated pulse, and the like when the resistance value of the resistor 10 is changed. FIG. 10 is a diagram illustrating the fifth embodiment and is a circuit diagram illustrating an igniter starting circuit to which an inductance L3 is added. FIG. 10 is a diagram illustrating the fifth embodiment, and illustrates measurement results of the secondary winding voltage VL2, 2.7 kV integrated pulse, and the like when the resistance value of the resistor 10 is changed in the circuit of FIG. 9; FIG. 17 is a circuit diagram showing an igniter starting circuit according to the sixth embodiment. The figure which shows Embodiment 6 is a figure which shows the result of having measured the secondary winding voltage VL2, 2.7 kV integrated pulse, etc. when changing the capacity | capacitance of the charging / discharging capacitor | condenser 12 and attaching load capacity in each capacity | capacitance value. .

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 DC power supply circuit, 2 1st switching element, 2nd switching element, 4 1st electrolytic capacitor, 5 2nd electrolytic capacitor, 6 Inductor, 7 Capacitor, 8 Step-up transformer, 8a Primary winding, 8b Secondary winding, 9 high-pressure discharge lamp, 10 resistor, 11 diode, 12 charge / discharge capacitor, 13 2-terminal thyristor, 14 control circuit.

Claims (6)

A load circuit to which a high-pressure discharge lamp is attached;
A DC power supply circuit for converting commercial power into a desired DC voltage;
An inverter circuit that converts a DC voltage from the DC power supply circuit into an AC voltage and supplies the AC voltage to the load circuit;
A step-up transformer having a secondary winding inserted in the load circuit; a two-terminal thyristor connected to the primary winding side of the step-up transformer; and a charge / discharge circuit provided between outputs of the DC power supply circuit An igniter starting circuit for generating a high voltage pulse in the secondary winding of the step-up transformer when the two-terminal thyristor is turned on;
When starting the high pressure discharge lamp of the load circuit, after the high pressure discharge lamp is lit, the charge voltage of the charge / discharge circuit becomes the voltage value for conducting the two-terminal thyristor. A control unit that controls the DC power supply circuit so as to have a voltage value that makes the terminal thyristor non-conductive,
A high pressure discharge lamp lighting device, characterized in that the winding ratio (secondary winding / primary winding) of the step-up transformer is set so that the secondary winding voltage is approximately 4.3 kV.   2. The high pressure discharge lamp lighting device according to claim 1, wherein the step-up transformer has a turns ratio (secondary winding / primary winding number) of 12 or less. A load circuit to which a high-pressure discharge lamp is attached;
A DC power supply circuit for converting commercial power into a desired DC voltage;
An inverter circuit that converts a DC voltage from the DC power supply circuit into an AC voltage and supplies the AC voltage to the load circuit;
A step-up transformer having a secondary winding inserted into the load circuit, a two-terminal thyristor connected to the primary winding side of the step-up transformer, and a connection between the primary winding of the step-up transformer and the two-terminal thyristor And an igniter start circuit for generating a high-voltage pulse in the secondary winding of the step-up transformer when the two-terminal thyristor is turned on, having a charge / discharge circuit provided between the output inductance and the output of the DC power supply circuit When,
When starting the high pressure discharge lamp of the load circuit, after the high pressure discharge lamp is lit, the charge voltage of the charge / discharge circuit becomes the voltage value for conducting the two-terminal thyristor. A high-pressure discharge lamp lighting device comprising: a control unit that controls the DC power supply circuit so as to have a voltage value that makes the terminal thyristor non-conductive.   4. The high pressure discharge lamp lighting device according to claim 3, wherein the inductance is 47 to 100 [mu] H.   4. The high pressure discharge lamp lighting device according to claim 3, wherein the charge / discharge circuit includes a resistor, and a resistance value of the resistor is about 20 kΩ.   4. The high pressure discharge lamp lighting device according to claim 3, wherein the charge / discharge circuit includes a charge / discharge capacitor, and a capacity of the charge / discharge capacitor is 0.1 ± 0.05 μF.

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