JP2009176637A - High pressure discharge lamp lighting device, and luminaire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high pressure discharge lamp lighting device having simple construction for keeping a peak value for starting high pulse voltage to be applied to both ends of a high pressure discharge lamp within a specified range by utilizing an output voltage varying function of a power conversion circuit. <P>SOLUTION: A starting pulse generation circuit 7 comprises a primary winding circuit having at least a capacitor C1, a primary winding N1 of a transformer T1 and a switching element Q7 connected in series to one another, a secondary winding circuit for connecting a secondary winding N2 of the transformer T1 to the high pressure discharge lamp 8 to apply high pulse voltage obtained by increasing voltage to be generated in the primary winding N1 of the transformer T1, to the high pressure discharge lamp 8, and a tertiary winding circuit for detecting the voltage level of the high pulse voltage through the voltage generated in a tertiary winding N3 of the transformer T1. Depending on a detected value for the high pulse voltage detected by the tertiary winding circuit, the sum of the high pulse voltage and the output voltage of the power conversion circuit during start is controlled to be kept within a predetermined range. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a high pressure discharge lamp lighting device having means for adjusting a peak value of a high voltage pulse voltage at start-up and a lighting fixture using the same.

  FIG. 24 is a block diagram showing a conventional high pressure discharge lamp lighting device. In the high pressure discharge lamp lighting device, when the commercial power supply 1 is turned on, the control power supply circuit 10 generates the control power supply, the control circuit 9 operates, the step-up chopper circuit 3, the step-down chopper circuit 4, the polarity inversion circuit 6, A control signal is sent to the start pulse generation circuit 7, and each starts operation. The step-up chopper circuit 3 boosts the output rectified by the rectifier circuit 2 to a prescribed voltage, and the step-down chopper circuit 4 adjusts the output so that the current flowing through the high-pressure discharge lamp 8 becomes a prescribed current. The polarity inversion circuit 6 outputs an AC rectangular wave voltage having a specified frequency to the high-pressure discharge lamp 8. The start pulse generation circuit 7 generates a high pressure pulse to start the high pressure discharge lamp 8.

  For example, the high-pressure discharge lamp has a high-voltage pulse voltage of 3 to 5 kV (peak value) at start-up. In the high pressure discharge lamp lighting device, when the output wiring length becomes long, the high voltage pulse voltage attenuates due to the increase in output capacity, so that it falls below the starting pulse voltage specified value of the high pressure discharge lamp. For example, when the output wiring length is 10 m, the high pressure discharge lamp Will not start. Therefore, the output wiring length of the high pressure discharge lamp lighting device has a regulation of 2 m or less, which is a constructional restriction. It may be designed so that a high voltage pulse voltage of 4 kV can be output even when the output wiring length is 10 m. However, when this high pressure discharge lamp lighting device is used with an output wiring length of 2 m or less, the high voltage pulse voltage is 5 or 6 kV (peak value) or more. There is a possibility of leakage in wiring, sockets, high pressure discharge lamps, etc.

Therefore, in Patent Document 1 (Japanese Patent Application Laid-Open No. 2007-52977), as shown in FIG. 25, even if the output wiring length increases and the output capacity increases by feeding back and fixing the high voltage pulse voltage, the high voltage pulse is increased. A high pressure discharge lamp lighting device capable of maintaining a voltage within a specified value is proposed. This high pressure discharge lamp lighting device has a start pulse generating circuit 7 for supplying a high pressure pulse voltage to the high pressure discharge lamp 8 at the start, and a control circuit 9 for controlling the start pulse generating circuit. The start pulse generation circuit 7 operates only when the high pressure discharge lamp 8 is started, and generates a high voltage pulse voltage. The start pulse generation circuit 7 includes a switching element Q7 that can be turned on / off by an external control signal, a capacitor C1 that rectifies the AC voltage of the commercial power source 1 and is charged by the DC voltage Vc3 boosted by the boost chopper circuit 3, and the switching element Q7 An inductor L1 that performs overcurrent protection of the transformer, a transformer T1 that boosts the high-voltage pulse voltage generated by turning on / off the switching element Q7, and a capacitor C2 that blocks the high-voltage pulse generated by the transformer T1 from entering the polarity inversion circuit 6 Have The voltage dividing circuit 11 that divides the voltage generated in the tertiary winding N3 provided in the transformer T1 and the starting pulse voltage component from the output of the voltage dividing circuit 11 are detected and fed back to the control circuit 9. And an output of the pulse detection circuit 12 is fed back to the control circuit 9. The control circuit 9 controls the switching element Q7 so that the high voltage pulse voltage is maintained within a specified value. The output of the voltage dividing circuit 11 includes various voltage components in addition to the necessary high voltage pulse voltage component. The pulse detection circuit 12 detects a high voltage pulse voltage component from this.
JP 2007-52977 A

  However, in the technique of Patent Document 1, in order to maintain the high voltage pulse voltage generated in the secondary winding N2 of the transformer T1 within a predetermined range, the charging voltage Vc1 of the capacitor C1 and the timing when the switching element Q7 is turned on are finely controlled. The configuration is complicated.

  The present invention has been made in view of the above problems, and by using the output voltage variable function of the power conversion circuit, the high voltage pulse voltage for starting applied to both ends of the high pressure discharge lamp can be simply configured. An object of the present invention is to provide a high pressure discharge lamp lighting device capable of maintaining a peak value within a specified range.

  In order to solve the above-mentioned problem, the invention of claim 1 converts the output of a DC power supply (step-up chopper circuit 3) to power to a high-pressure discharge lamp 8 which is a load, as shown in FIGS. A power conversion circuit (step-down chopper circuit 4) for supplying power, a polarity inversion circuit 6 for converting the output of the power conversion circuit into a rectangular wave alternating current and applying it to the high-pressure discharge lamp 8, and a high-pressure pulse voltage for starting the high-pressure discharge lamp In the high pressure discharge lamp lighting device comprising a start pulse generating circuit 7 applied to 8 and control circuits 30, 40, 60, 90 for controlling the respective circuits, the start pulse generating circuit 7 includes at least a capacitor C1 and a transformer T1. A primary winding circuit comprising a series connection of a primary winding N1 and a switching element Q7 and a secondary winding N2 of the transformer T1 are connected to a high-pressure discharge lamp 8 and are generated in the primary winding N1 of the transformer T1. To increase the voltage A secondary winding circuit for applying the high-voltage pulse voltage to the high-pressure discharge lamp 8, and a tertiary winding for detecting the voltage level of the high-voltage pulse voltage by the voltage generated in the tertiary winding N3 provided in the transformer T1. The control circuit 30, 40, 60, 90 comprises a high voltage pulse voltage and an output of the power conversion circuit at the start according to the detected value of the high voltage pulse voltage detected by the tertiary winding circuit. Control is performed such that the sum of the voltages is maintained within a predetermined range.

  According to a second aspect of the present invention, in the first aspect of the invention, the control circuit maintains the sum of the high voltage pulse voltage and the output voltage of the power conversion circuit at start-up within a specified value range required from the high pressure discharge lamp. It is characterized by controlling as follows.

  According to a third aspect of the present invention, in the first aspect of the present invention, the control circuits 30 and 40 are configured so that the sum of the high voltage pulse voltage and the output voltage of the power conversion circuit at the start is maintained within a predetermined range. A high pressure discharge lamp lighting device (FIGS. 4 and 5) characterized in that the output voltage of the lamp is changed.

  According to a fourth aspect of the present invention, in the first to third aspects of the present invention, the control circuit 40 is configured to output the high voltage pulse voltage and the output voltage of the power conversion circuit at the start only when a rectangular wave having the same polarity as the high voltage pulse voltage is output. Control is performed so as to maintain the sum of the values within a predetermined range (FIG. 20).

  According to a fifth aspect of the present invention, in the first to fourth aspects of the invention, the control circuit 40 changes the output voltage of the power conversion circuit only during a period in which the switching element Q7 of the start pulse generating circuit 7 is on. (FIG. 22).

  According to a sixth aspect of the present invention, in the first aspect of the present invention, the control circuit 40 controls the power conversion circuit to output a voltage that changes at the time of starting, thereby converting the high voltage pulse voltage and the power conversion at the time of starting. The switching element Q7 of the start pulse generation circuit 7 is turned on when the output voltage of the power conversion circuit is such that the sum of the output voltages of the circuits falls within a predetermined range (FIG. 10).

  The invention of claim 7 is characterized in that, in the invention of claim 6, the control circuit 40 continuously changes the output voltage of the power conversion circuit in a half-cycle section of a rectangular wave (FIG. 11).

  The invention of claim 8 is characterized in that, in the invention of claim 6, the control circuit 40 changes the output voltage of the power conversion circuit stepwise in a half-cycle section of a rectangular wave (FIG. 17).

  According to a ninth aspect of the present invention, in the first to eighth aspects of the invention, the control circuit operates the start pulse generating circuit only for a rectangular wave polarity having the same polarity as that of the high voltage pulse voltage (FIG. 20). ).

  A tenth aspect of the present invention is a luminaire including the high pressure discharge lamp lighting device according to the first to ninth aspects (FIG. 23).

  According to the present invention, since the output voltage variable function of the power conversion circuit is used, the amplitude of the rectangular wave AC output superimposed on the high voltage pulse voltage is made variable so that it is applied to both ends of the high pressure discharge lamp. The peak voltage can be maintained within a specified range. The power conversion circuit of the high-pressure discharge lamp lighting device functions as a ballast for stable lighting, so it is configured to output a fixed voltage that is set arbitrarily, and it is relatively easy to change its output target value. Can be realized. In the present invention, the sum of the high voltage pulse voltage and the output voltage of the power conversion circuit is controlled to be maintained within a predetermined range based on the detected value of the high voltage pulse voltage obtained from the tertiary winding of the transformer that generates the high voltage pulse voltage. Thus, it is possible to provide a high-pressure discharge lamp lighting device that can be reliably started without generating an unnecessary high voltage while having an inexpensive configuration.

(Embodiment 1)
FIG. 1 is a block diagram of Embodiment 1 of the present invention. The step-up chopper circuit 3 is used as a part of the DC power supply, and the step-down chopper circuit 3 is used as a power conversion circuit. FIG. 2 is a detailed diagram of the step-up chopper circuit 3, the step-down chopper circuit 4, the start pulse voltage generation circuit 7, and the control circuits 30 and 40 of each chopper circuit.

  The circuit configuration of the boost chopper circuit 3 will be described. A series circuit of an inductor L2 and a switching element Q1 is connected to the output terminal of the rectifier circuit 2, and a smoothing capacitor C3 is connected to both ends of the switching element Q1 via a diode D1. The inductor L2, the switching element Q1, the diode D1, and the smoothing capacitor C3 constitute a boost chopper circuit 3. On / off of the switching element Q1 is controlled by the boost chopper control circuit 30. When the switching element Q1 is on / off controlled at a frequency sufficiently higher than the commercial frequency of the commercial AC power supply 1, the output voltage of the rectifier circuit 2 is boosted to a specified DC voltage and charged to the smoothing capacitor C3. At the same time, power factor improvement control is performed to give resistance to the circuit so that the phase of the input current and the input voltage from the commercial AC power supply 1 is not shifted. A filter circuit for preventing high frequency leakage may be provided at the AC input end of the rectifier circuit 2.

  The direct current power source used in the present embodiment is a direct current voltage of the smoothing capacitor C3 obtained by rectifying and smoothing the commercial alternating current power source 1, and the output voltage of the boost chopper circuit 3 connected to the output of the rectifier circuit 2, but is not limited thereto. However, the DC power source may be a battery or a commercially available DC power source.

  A step-down chopper circuit 4 as a power conversion circuit is connected to the DC power source. The step-down chopper circuit 4 has a function as a ballast for supplying target power to a high-pressure discharge lamp 8 that is a load. Further, the output voltage of the step-down chopper circuit 4 is variably controlled so that appropriate power is supplied to the high-pressure discharge lamp 8 from the start through the arc discharge transition period to the stable lighting period.

  A circuit configuration of the step-down chopper circuit 4 will be described. The positive electrode of the smoothing capacitor C3, which is a DC power supply, is connected to the positive electrode of the capacitor C4 via the switching element Q2 and the inductor L3, and the negative electrode of the capacitor C4 is connected to the negative electrode of the smoothing capacitor C3. The negative electrode of the capacitor C4 is connected to the anode of the diode D2 for energizing the regenerative current, and the cathode of the diode D2 is connected to the connection point between the switching element Q2 and the inductor L3.

  The circuit operation of the step-down chopper circuit 4 will be described. The switching element Q2 is driven on and off at a high frequency by a control signal from the step-down chopper control circuit 40. When the switching element Q2 is on, a current is supplied from the output of the step-up chopper circuit 3 through the switching element Q2, the inductor L3, and the capacitor C4. When the switching element Q2 is off, a regenerative current flows through the inductor L3, the capacitor C4, and the diode D2. As a result, a DC voltage obtained by stepping down the output voltage of the step-up chopper circuit 3 is charged in the capacitor C4. The voltage obtained at the capacitor C4 can be variably controlled by changing the on-duty (ratio of on-time occupying one cycle) of the switching element Q2 by the step-down chopper control circuit 40.

  A polarity inversion circuit 6 is connected to the output of the step-down chopper circuit 4. The polarity inversion circuit 6 is a full bridge circuit composed of four switching elements, and in synchronization with the rectangular wave polarity switching signal from the rectangular wave control circuit 60, the output power of the step-down chopper circuit 4 is converted to a low-frequency rectangular wave AC power. And is supplied to the high pressure discharge lamp 8. The high-pressure discharge lamp 8 as a load is a high-intensity high-pressure discharge lamp (HID lamp) such as a metal halide lamp or a high-pressure mercury lamp.

  The control circuit 40 of the step-down chopper circuit 4 includes a steady-state control circuit 43 that sets an output target value of the step-down chopper circuit 4 during steady operation, and a high-voltage pulse voltage detected by the pulse detection circuit 12 during start-up. The start time control circuit 44 that sets the output target value of the step-down chopper circuit 4 in comparison with the value, and the output current of the step-down chopper circuit 4 is detected, and the start time control circuit 44 and the steady state control circuit 43 are switched. FET control for controlling on / off of the switching element Q2 based on inputs from the switching circuit 50, the output detection circuit 41 for detecting the output of the step-down chopper circuit 4, and the start-time control circuit 44 or the steady-state control circuit 43 The circuit 42 is formed.

  The control circuit 30 of the step-up chopper circuit 3 includes a steady-state control circuit 33 that sets a target output value of the step-up chopper circuit 3 during steady operation and a start-up control circuit that sets a target output value of the boost chopper circuit 3 during start-up. 34, an output detection circuit 31 for detecting the output of the step-up chopper circuit 3, and an FET control circuit 32 for controlling on / off of the switching element Q1 based on an input from the start-up control circuit 34 or the steady-state control circuit 33. Consists of.

  FIG. 3 is a waveform of each part when the output wiring length to the high-pressure discharge lamp 8 is short and the stray capacitance of the wiring is very small. At this time, the maximum value of the high-voltage pulse voltage after boosting the transformer T1 is set as the target value Vm of the high-voltage pulse voltage, and the output voltage value of the step-down chopper circuit 4 is set as the normal output target value Vr of the step-down chopper circuit 3.

  FIG. 4 is a waveform of each part when the output wiring length to the high pressure discharge lamp 8 is long and the high voltage pulse voltage after boosting the transformer T1 is attenuated due to the floating capacitance of the wiring. The high voltage pulse voltage after the boosting of the transformer T1 is detected by the tertiary winding N3 of the transformer T1, and after the voltage is divided by the voltage dividing circuit 11, the high voltage pulse voltage component is detected by the pulse detecting circuit 12, and the voltage is lowered. This is fed back to the start-up control circuit 44 in the chopper control circuit 40. The starting-time control circuit 44 determines the output target value of the step-down chopper circuit 4 from the difference between the fed back high voltage pulse voltage Vp and the target value Vm of the high voltage pulse voltage (the insufficient voltage ΔV from the target value). Is set higher by ΔV than the normal target value Vr. The FET control circuit 42 of the step-down chopper control circuit 40 receives the output of the starting control circuit 44 and controls the switching element Q2. The output detection circuit 41 detects the output voltage of the step-down chopper circuit 4 and feeds it back to the FET control circuit 42. Thus, the output voltage of the step-down chopper circuit 4 is controlled to become the output target value.

  FIG. 5 shows respective waveforms when the output target value Vd of the step-down chopper circuit 4 set by the start-up control circuit 44 of the step-down chopper control circuit 40 is higher than the input voltage of the step-down chopper circuit 4. At this time, the start time control circuit 44 of the step-down chopper control circuit 40 transmits the output target value Vd to the start time control circuit 34 of the step-up chopper control circuit 30. The startup control circuit 34 of the step-up chopper control circuit 30 sets a voltage higher than the output target value Vd of the step-down chopper circuit 4 as the output target value Vu of the step-up chopper circuit 3. The FET control circuit 32 of the step-up chopper control circuit 30 receives the output of the startup control circuit 34 and controls the switching element Q1. The output detection circuit 31 detects the output voltage of the boost chopper circuit 3 and feeds it back to the FET control circuit 32. By increasing the output voltage of the step-up chopper circuit 3 in this way, the input voltage of the step-down chopper circuit 4 is increased, and the upper limit of the output of the step-down chopper circuit 4 can be widened.

  FIG. 6 shows the configuration of the start time control circuit 44 of the step-down chopper control circuit 40 of the present embodiment. In addition, FIG. 7 shows operation waveforms of respective units corresponding to the case of FIG. The start-up control circuit 44 includes a peak value detector 44a, a high voltage pulse change detector 44b, and a step-down chopper circuit output target value setting unit 44c. The peak value detection unit 44a receives the feedback of the high voltage pulse voltage from the pulse detection circuit 12, and detects the peak value Vp of the high voltage pulse voltage. The high voltage pulse change detector 44b calculates and outputs the difference between the peak value Vp of the high voltage pulse voltage and the target value Vm of the high voltage pulse voltage. The step-down chopper circuit output target value setting unit 44c adds the high-voltage pulse voltage change ΔV to the reference voltage Vr of the step-down chopper circuit 4 and outputs it to the FET control circuit 42 as the step-down chopper circuit output target value.

  As described above, by compensating the shortage of the high voltage pulse voltage after boosting by the transformer T1 with the output voltage of the step-down chopper circuit 4, the peak value of the voltage across the high pressure discharge lamp 8 at the time of starting is always kept constant. Can do.

(Embodiment 2)
FIG. 8 is a block diagram of Embodiment 2 of the present invention. FIG. 9 is a detailed diagram of the step-up chopper circuit 3, the step-down chopper circuit 4, the start pulse voltage generation circuit 7, and the control circuits 30 and 40 of each chopper circuit.

  The step-down chopper control circuit 40 is a steady-state control circuit 43 that sets a target output value of the step-down chopper circuit during steady operation, and a start-time control circuit that sets the output voltage of the step-down chopper circuit 4 to have a certain change during start-up. 44, a state switching circuit 50 that detects the output current of the step-down chopper circuit 4 and switches between the start-time control circuit 44 and the steady-state control circuit 43, and an output detection circuit 41 that detects the output of the step-down chopper circuit 4. The FET control circuit 42 controls ON / OFF of the switching element Q2 based on an input from the start-time control circuit 44 or the steady-state control circuit 43.

  FIG. 10 shows operation waveforms of each part.

  When there is no load, control is performed so that the output voltage of the step-down chopper circuit 4 changes a certain amount as shown in FIG. The horizontal axis is time, and the vertical axis is voltage value. Here, a voltage waveform after the output voltage of the step-down chopper circuit 4 is converted into a low-frequency AC output by the polarity inversion circuit 6 is shown. The period of the low frequency alternating current is generally several hundred Hz, and the amplitude is several hundred volts.

  The start pulse generation circuit control circuit 90 includes an FET control circuit 96 that performs on / off control of the switching element Q7, and a step-down chopper circuit output change detection circuit 97 that detects the amount of change in the output of the step-down chopper circuit 4. The FET control circuit 96 of the start pulse generation circuit control circuit 90 includes an output from the pulse detection circuit 12 (a decrease value of the high voltage pulse voltage) and an output of the step-down chopper circuit output change detection circuit 97 (an increase value of the step-down chopper circuit output). When the two become equal, the switching element Q7 is turned on.

  FIG. 12 shows a specific circuit configuration example of the start-up control circuit 44 of the step-down chopper control circuit 40 of the present embodiment. The starting control circuit 44 charges the capacitor through the constant current circuit, and discharges the capacitor during the polarity switching operation of the polarity reversing circuit 6, thereby outputting an output target value as shown in FIG.

  14 and 15 show the configuration of the start pulse generation circuit control circuit 90. FIG. FIG. 16 is an operation waveform of each part.

  FIG. 14 shows details of the step-down chopper circuit output change detection circuit 97 in the start pulse generation circuit control circuit 90. This circuit is composed of an operational amplifier, calculates the output change value of the step-down chopper circuit 4, and outputs it to the FET control circuit 96.

  FIG. 15 shows details of the FET control circuit 96 in the start pulse generation circuit control circuit 90. The peak value detector 96a and the high voltage pulse voltage change detector 96b of the FET control circuit 96 calculate the change ΔV in the high voltage pulse voltage from the feedback of the high voltage pulse voltage in the same manner as in the first embodiment, and the FET gate voltage controller Output to 96c. The FET gate voltage control unit 96c turns on the switching element Q7 when the step-down chopper circuit output change value becomes equal to the change ΔV of the high voltage pulse voltage, and generates a high voltage pulse voltage. Thereby, the change (decrease) in the high voltage pulse voltage can be supplemented with the change (increase) in the output voltage from the polarity inversion circuit 6, and the peak voltage applied to both ends of the high pressure discharge lamp 8 at the start can be obtained. It can be kept almost constant.

  In this embodiment, as shown in FIG. 11, the output voltage of the step-down chopper circuit 4 is changed so as to continuously change from polarity inversion, but the change in the output voltage is limited to this. Alternatively, as shown in FIG. 17, it may be changed stepwise. When the output voltage of the step-down chopper circuit 4 changes stepwise, the output value from the pulse detection circuit 12 (decrease value of the high-voltage pulse voltage) and the output value of the step-down chopper circuit output change detection circuit 97 (the output of the step-down chopper circuit) The FET control circuit 96 is set so that the switching element Q7 is turned on when the increase value is closest. When the step-down chopper circuit output voltage changes stepwise as shown in FIG. 17, the peak voltage of the voltage across the high-pressure discharge lamp 8 cannot be continuously adjusted in accordance with the change in the high-voltage pulse voltage. Even if there is an influence of the signal delay time in the control circuit, there is an advantage that the peak voltage of the voltage across the high-pressure discharge lamp 8 can be easily adjusted to a target value.

(Embodiment 3)
FIG. 18 is a block diagram showing the overall configuration of the third embodiment of the present invention. The configuration for detecting and feeding back the high-voltage pulse voltage after boosting the transformer T1 and adjusting the output of the step-down chopper circuit 4 is the same as that of FIG. The rectangular wave control circuit 60 controls the polarity switching operation of the polarity inverting circuit 6.

  In the present embodiment, the start time control circuit 44 of the step-down chopper control circuit 40 detects the rectangular wave polarity switching signal from the rectangular wave control circuit 60 and only during the half cycle of the rectangular wave output having the same polarity as the high voltage pulse voltage, The output target value of the step-down chopper circuit 4 is set according to the amount of change in the high voltage pulse voltage.

  Further, the start pulse generation circuit control circuit 90 detects the rectangular wave polarity switching signal from the rectangular wave control circuit 60 and generates the high voltage pulse voltage only during the half wave output half cycle of the same polarity as the high voltage pulse voltage. For example, assuming that the polarity of the rectangular wave output voltage is the same as that of the high voltage pulse voltage when the polarity of the rectangular wave output voltage is positive, the FET control circuit 96 of the start pulse generation circuit control circuit 90 is switched when the polarity of the rectangular wave output voltage is switched from negative to positive. The element Q7 is turned on.

  FIG. 19 shows the configuration of the starting control circuit 44 of the step-down chopper control circuit 4 in the present embodiment. The transistor Tr is added to the output portion of the high voltage pulse change detector 44b of the start time control circuit 44 (FIG. 6) of the first embodiment, and when the transistor Tr is turned on, the output of the high voltage pulse change detector 44b is dropped to the ground. By applying a rectangular wave polarity switching signal from the rectangular wave control circuit 60 to the base of the transistor Tr, the transistor Tr is turned on only during a half cycle in which the polarity of the rectangular wave output voltage is different from that of the high voltage pulse voltage. The output voltage of the detector 44b is set to zero, and the output target value of the step-down chopper circuit 4 is made equal to the reference output voltage.

  FIG. 20 shows the operation waveform of each part. As is apparent from the figure, there are combinations where the output adjustment of the step-down chopper circuit 4 does not work effectively in the combinations of the polarities of the high voltage pulse voltage and the rectangular wave output. By adjusting the output of the step-down chopper circuit 4 only during the half-cycle of the rectangular wave output having the same polarity as the high-voltage pulse voltage, the peak voltage applied to both ends of the high-pressure discharge lamp is compared with the case where the output voltage effective value is equivalent. Can be widened, and unnecessary high voltage pulse voltage can be avoided.

(Embodiment 4)
FIG. 21 is a circuit diagram showing the overall configuration of Embodiment 4 of the present invention. A configuration that detects and feeds back a high-voltage pulse voltage that has been boosted by the transformer T1, and adjusts the output of the step-down chopper circuit 4. The start pulse generation circuit control circuit 90 detects the polarity switching operation signal of the rectangular wave control circuit 60 and detects the high-voltage pulse. The configuration for controlling the voltage generation is the same as in the third embodiment.

  FIG. 22 shows operation waveforms of each part. The start-up control circuit 44 of the step-down chopper control circuit 40 detects the rectangular wave polarity switching signal from the rectangular wave control circuit 60, and the high voltage pulse is output only for a certain time during a half cycle of the rectangular wave output having the same polarity as the high voltage pulse voltage. An output target value of the step-down chopper circuit 4 is set according to the voltage change amount, and the output of the step-down chopper circuit 4 is adjusted.

  For example, assuming that the output adjustment of the step-down chopper circuit 4 is effective when the voltage polarity of the rectangular wave output is positive, the start pulse generation circuit control circuit 90 is used when the voltage polarity of the rectangular wave output is switched from negative to positive. Switching element Q7 is turned on.

  The start-up control circuit 44 of the step-down chopper control circuit 40 sets the output target value of the step-down chopper circuit according to the amount of change in the high-voltage pulse voltage when the voltage polarity of the rectangular wave output is switched from negative to positive. That is, the output target value of the step-down chopper circuit 4 is temporarily raised so as to compensate for the shortage ΔVp of the high voltage pulse voltage. Thereafter, when the start pulse generation circuit control circuit 90 turns off the switching element Q7, the start time control circuit 44 of the step-down chopper control circuit 40 reduces the output target value of the step-down chopper circuit 4.

  Thus, by adjusting the output of the step-down chopper circuit 4 only when generating a high-voltage pulse voltage, the effective voltage value of the high-pressure discharge lamp 8 can be significantly reduced compared to the first embodiment. Compared to the case where the effective values are equivalent, the adjustment range of the peak value of the pulse voltage applied to both ends of the high-pressure discharge lamp can be expanded, and unnecessary generation of the high-voltage pulse voltage can be avoided.

  In each of the embodiments described above, the polarity inversion circuit 6 is assumed to be a full bridge circuit, but may be a half bridge circuit. The step-down chopper circuit 4 as a power conversion circuit may also be used as a switching element of a full bridge circuit or a half bridge circuit constituting the polarity inversion circuit 6.

(Embodiment 5)
FIG. 23 shows a configuration example of a lighting fixture using the high pressure discharge lamp lighting device of the present invention. (A), (b) is an example using an HID lamp as a spotlight, and (c) is an example using an HID lamp as a downlight. In the figure, 8 is a high pressure discharge lamp, 81 is a high pressure discharge lamp. A mounted lamp body, 82 is a wiring, and 83 is a ballast storing a circuit of a lighting device. A lighting system may be constructed by combining a plurality of these lighting fixtures. By using the high pressure discharge lamp lighting device according to any of the first to fourth embodiments as these lighting devices, the peak value of the start pulse can be optimized, and the start can be started even if the wiring 82 is long. Further, when the wiring 82 is short, the peak value of the starting pulse can be reduced.

  By installing the high pressure discharge lamp lighting device of the present invention in which the high voltage pulse voltage is not attenuated even if the output line length is extended, the wiring 82 can be extended in the range of 2 m to 10 m, for example, and the workability is improved. Thus, the ballast 83 can be installed in a lump, and there is an advantage that the distance of the power line can be shortened and the ballast 83 can be checked in a lump.

It is a block diagram which shows schematic structure of Embodiment 1 of this invention. It is a block circuit diagram which shows the specific structure of Embodiment 1 of this invention. It is an operation | movement waveform diagram when the output line length of Embodiment 1 of this invention is the shortest. It is an operation | movement waveform diagram when the output line length of Embodiment 1 of this invention is an intermediate | middle. It is an operation | movement waveform diagram when the output line length of Embodiment 1 of this invention is the longest. It is a circuit diagram which shows the principal part structure of Embodiment 1 of this invention. It is an operation | movement waveform diagram of Embodiment 1 of this invention. It is a block diagram which shows schematic structure of Embodiment 2 of this invention. It is a block circuit diagram which shows the specific structure of Embodiment 2 of this invention. It is an operation | movement waveform diagram of Embodiment 2 of this invention. It is a wave form diagram which shows the output change at the time of no load of the polarity inversion circuit of Embodiment 2 of this invention. It is a circuit diagram which shows the detail of the starting time control circuit of the pressure | voltage fall chopper circuit of Embodiment 2 of this invention. It is a wave form diagram which shows the change of the output target value at the time of starting of the pressure | voltage fall chopper circuit of Embodiment 2 of this invention. It is a circuit diagram which shows the detail of the output change detection circuit of the pressure | voltage fall chopper circuit of Embodiment 2 of this invention. It is a circuit diagram which shows the detail of the starting pulse generation circuit control circuit of Embodiment 2 of this invention. It is an operation | movement waveform diagram of Embodiment 2 of this invention. It is a wave form diagram which shows another example of the output change at the time of no load of the polarity inversion circuit of Embodiment 2 of this invention. It is a block diagram which shows schematic structure of Embodiment 3 of this invention. It is a circuit diagram which shows the detail of the starting time control circuit of the pressure | voltage fall chopper circuit of Embodiment 3 of this invention. It is an operation | movement waveform diagram of Embodiment 3 of this invention. It is a block circuit diagram which shows the specific structure of Embodiment 4 of this invention. It is an operation | movement waveform diagram of Embodiment 4 of this invention. It is a perspective view which shows the external appearance of the lighting fixture of Embodiment 5 of this invention. It is a block diagram of a prior art example. It is a circuit diagram of a conventional example.

Explanation of symbols

3 Boost chopper circuit (DC power supply)
4 Step-down chopper circuit (power conversion circuit)
6 polarity inversion circuit 7 start pulse generation circuit C1 capacitor Q7 switching element T1 transformer N1 primary winding N2 secondary winding N3 tertiary winding 8 high voltage discharge lamp 30 step-up chopper control circuit 40 step-down chopper control circuit 60 rectangular wave control circuit 90 Start pulse generation circuit control circuit

Claims (10)

A power conversion circuit that converts the output of the DC power source to supply power to the high-pressure discharge lamp as a load;
A polarity inversion circuit that converts the output of the power conversion circuit into a rectangular wave alternating current and applies it to the high-pressure discharge lamp;
A starting pulse generating circuit for applying a high voltage pulse voltage for starting to the high pressure discharge lamp;
In the high pressure discharge lamp lighting device provided with a control circuit for controlling each circuit,
The starting pulse generating circuit is
A primary winding circuit comprising at least a primary connection of a capacitor, a transformer, and a switching element;
A secondary winding circuit for connecting a secondary winding of the transformer to a high-pressure discharge lamp and applying a high-voltage pulse voltage obtained by boosting a voltage generated in the primary winding of the transformer to the high-pressure discharge lamp;
A tertiary winding circuit that detects a voltage level of a high-voltage pulse voltage based on a voltage generated in a tertiary winding provided in the transformer;
The control circuit maintains the sum of the high voltage pulse voltage and the output voltage of the power conversion circuit at the start in a predetermined range according to the detected value of the high voltage pulse voltage detected by the tertiary winding circuit. A high pressure discharge lamp lighting device characterized by controlling. 2. The control circuit according to claim 1, wherein the control circuit controls the sum of the high voltage pulse voltage and the output voltage of the power conversion circuit at the time of starting to be within a specified value range required from the high pressure discharge lamp. High pressure discharge lamp lighting device. 2. The high voltage according to claim 1, wherein the control circuit changes the output voltage of the power conversion circuit so as to maintain a sum of the high voltage pulse voltage and the output voltage of the power conversion circuit at the time of start in a predetermined range. Discharge lamp lighting device. 4. The control circuit according to claim 1, wherein the control circuit sets the sum of the high voltage pulse voltage and the output voltage of the power conversion circuit at the start within a predetermined range only when a rectangular wave having the same polarity as the high voltage pulse voltage is output. A high pressure discharge lamp lighting device characterized by controlling to maintain. 5. The high-pressure discharge lamp lighting according to claim 1, wherein the control circuit changes the output voltage of the power conversion circuit only during a period in which the switching element of the start pulse generation circuit is on. apparatus. 2. The control circuit according to claim 1, wherein the control circuit controls the power conversion circuit to output a voltage that changes at a start, and a sum of the high voltage pulse voltage and the output voltage of the power conversion circuit at the start is within a predetermined range. A high pressure discharge lamp lighting device, wherein the switching element of the start pulse generation circuit is turned on at the time of the output voltage of the power conversion circuit. 7. The high pressure discharge lamp lighting device according to claim 6, wherein the control circuit continuously changes the output voltage of the power conversion circuit in a half-cycle section of a rectangular wave. 7. The high pressure discharge lamp lighting device according to claim 6, wherein the control circuit changes the output voltage of the power conversion circuit in a stepped manner in a half-cycle section of a rectangular wave. 9. The high pressure discharge lamp lighting device according to claim 1, wherein the control circuit operates the start pulse generating circuit only for a rectangular wave polarity having the same polarity as that of the high voltage pulse voltage. A lighting fixture comprising the high pressure discharge lamp lighting device according to any one of claims 1 to 9.

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