JP2008243467A - Discharge lamp lighting device, luminaire, and illumination system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a discharge lamp lighting device capable of more accurately discriminating the rated power of the lamp by using a ballast characteristic to suppress a great change in the lamp voltage rising characteristic in lamp discrimination even when there occurs a voltage fluctuation factor. <P>SOLUTION: The discharge lamp lighting device is equipped with a power converting circuit for converting power from a direct-current power source and supplying power to a high-voltage discharge lamp and a lighting control circuit for controlling power supplied to the power converting circuit and works to control a plurality of kinds of high-voltage discharge lamps as loads, discriminate their types, and light the high-voltage discharge lamps with rated power. The period to discriminate the type of a high-voltage discharge lamp is until the luminance or lamp voltage of the discharge lamp becomes stable. The discharge lamp lighting device lights a high-voltage discharge lamp with an approximately constant lamp power, discriminates the type of the high-voltage discharge lamp by a period during which the lamp voltage in the discrimination period changes from a first lamp voltage to a second lamp voltage, and lights the connected high-voltage discharge lamp with a voltage selected according to the result of discrimination. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a discharge lamp lighting device, a lighting fixture using the same, and a lighting system, and more particularly to a discharge lamp lighting device for lighting a plurality of types of high-pressure discharge lamps connected to one of them. It is.

  FIG. 11 shows the ballast characteristics of a general high-pressure discharge lamp lighting device with a rated power of 70 W. The solid line indicates the lamp voltage-lamp current characteristic, and the broken line indicates the lamp voltage-lamp power characteristic. The ballast characteristic includes a constant current characteristic composed of a starting current value defined in the lamp specification and a constant power characteristic composed of a rated power value similarly defined in the lamp specification. When the lamp is started with this ballast characteristic, the ramp voltage rise characteristic as shown in FIG. 12 is obtained. From FIG. 12, it can be seen that the rise characteristic of the lamp voltage until the lamp voltage is stabilized is a quadratic function. Further, comparing the ramp voltage rise characteristics of the initial start characteristic and the restart characteristic, it can be confirmed that there is a large difference in the time for the lamp voltage to change from 30V to 40V. Therefore, if it is attempted to determine the lamp rated power by measuring the rise time of the lamp voltage during the start-up period due to the constant current characteristic, it can be said that the determination results are likely to vary.

  In Patent Document 1 (Japanese Patent Laid-Open No. 2005-310676), a high-pressure discharge lamp that detects the time until the lamp voltage of the high-pressure discharge lamp changes from a first voltage to a second voltage to determine the type of the discharge lamp. A lighting device has been proposed. In Patent Document 1, the ballast characteristic (lamp voltage-lamp current characteristic) at the time of lamp discrimination is not disclosed. Further, according to the disclosed ramp voltage rise characteristic when the lamp is lit, the lamp voltage increases to a quadratic function until the lamp is stable. Therefore, when trying to discriminate the lamp with the elapsed time from 30 V to 40 V described in Patent Document 1, it largely depends on the lamp voltage characteristics until the lamp voltage reaches 30 V, and the initial start and restart Depending on conditions such as the lamp lighting direction and life, the lamp characteristics change until the lamp voltage reaches 30V, and as a result, the time during which the lamp voltage changes from 30V to 40V tends to vary.

Patent Document 2 (Japanese Patent Laid-Open No. 2005-310678) discloses a ballast characteristic of a discharge lamp lighting device for determining the type of a high-pressure discharge lamp. However, in the ballast characteristic (substantially constant lamp current) at the time of the lamp discrimination, the lamp power increases as the lamp voltage rises. Therefore, the rise characteristic of the lamp voltage becomes a quadratic function, and the discharge lamp is discharged during this period. When the type of lamp is determined, the time until the lamp voltage changes from 30 V to 40 V is likely to vary depending on the characteristics such as initial start-up and restart.
JP 2005-310676 A Japanese Patent Laying-Open No. 2005-310678

  It is possible to discriminate almost all lamps by the conventional techniques disclosed in Patent Documents 1 and 2. However, depending on factors such as the initial start, restart, lighting direction, and life of the lamp, the difference in the determination time between lamps with different rated power (the time for the lamp voltage to change from 30 V to 40 V) is reduced, and the determination is made. It can be difficult.

  Therefore, in the present invention, a discharge lamp lighting device that can more reliably determine the rated power of the lamp by using a ballast characteristic that does not significantly change the rising characteristic of the lamp voltage at the time of lamp discrimination even when the variation factor occurs. It is an issue to provide.

  In order to solve the above problems, a discharge lamp lighting device according to the present invention converts a power from a DC power source to supply power to a high-pressure discharge lamp, and a lighting for controlling power supplied to the power conversion circuit A discharge lamp lighting device for controlling a plurality of types of high-pressure discharge lamps, determining the type of the high-pressure discharge lamp, and lighting the high-pressure discharge lamp at a rated level, and determining the type of the high-pressure discharge lamp The period is until the illuminance or lamp voltage of the discharge lamp is stabilized, and the high-pressure discharge lamp is turned on with substantially constant lamp power, and the lamp voltage in the determination period is changed from the first lamp voltage to the first lamp voltage. The type of the high-pressure discharge lamp is discriminated based on the time when the second lamp voltage changes to a larger value, and the connected high-pressure discharge lamp is turned on with the electric power selected based on the discrimination result.

  According to the present invention, the lamp rated power is determined by measuring the rise time of the lamp voltage according to the constant power characteristics, so the lamp rated power is determined by measuring the rise time of the lamp voltage during the start-up period according to the conventional constant current characteristics. Compared to the case, the measurement result of the rise time of the lamp voltage is less likely to vary, and therefore the type of the discharge lamp can be more reliably determined.

(Embodiment 1)
FIG. 3 shows a circuit diagram of the discharge lamp lighting device according to Embodiment 1 of the present invention. This circuit includes a discharge lamp discrimination circuit 6 including a microcomputer IC1 that detects the lamp voltage of the discharge lamp DL as a divided voltage of the resistors R4 and R5. When the power is turned on, the lamp discrimination period (for example, the lamp voltage is 30V). In the period from 40 to 40 V), as indicated by the broken line in FIG. 1, the lamp is lit with a constant power characteristic (for example, a constant power value of 30 W), and the lamp voltage is changed from the first voltage (30 V) to the second voltage (40 V). ) To determine the type of discharge lamp.

  With the ballast characteristic shown in FIG. 1, the lamp voltage rising characteristic when the high pressure discharge lamp is started is as shown in FIG. From FIG. 2, the ramp-up characteristic of the lamp voltage until the lamp voltage becomes stable is a linear function. Further, when comparing the initial start characteristic and the restart characteristic of the lamp voltage rising characteristic, it can be confirmed that the time required for the lamp voltage to change from 30 V to 40 V is substantially the same. Therefore, it is possible to more reliably perform the discrimination by discriminating a plurality of types of lamps with the high pressure discharge lamp lighting device of the present invention.

  First, the circuit of FIG. 3 will be described. For example, a DC voltage obtained by rectifying and smoothing a commercial AC power supply by a step-up chopper circuit is applied to the electrolytic capacitor C1 as a DC power supply. In this circuit, this DC voltage is kept constant at, for example, about 300 V, and this is the lamp end-to-end voltage (no-load secondary voltage) required for starting the HID lamp. Yes.

  The control power supply circuit 1 is composed of voltage dividing resistors R1 and R2 and a Zener diode ZD1, and generates a voltage Vcc to be supplied to the control circuit.

  The step-down chopper circuit 2 includes a switching element Q1, a regenerative diode D1, an inductor L1, and a capacitor C2. When the switching element Q1 switches at a high frequency, the DC voltage stored in the electrolytic capacitor C1 is necessary for the lamp DL. Convert to electricity.

  The polarity inversion circuit 3 is composed of a full bridge circuit of switching elements Q2, Q3, Q4, and Q5. Under the control of the full bridge control circuit, the DC voltage of the capacitor C2 of the step-down chopper circuit 2 is several tens Hz to several hundreds Hz. Convert to low frequency rectangular wave.

  The igniter circuit 4 includes a pulse transformer and a pulse generation circuit, and generates a high-pressure pulse (about 3 to 5 kV) necessary for starting the lamp.

  The discharge lamp discriminating circuit 6 detects the lamp voltage of the discharge lamp DL and discriminates a plurality of types of discharge lamps. For example, it is composed of a general-purpose microcomputer IC1 such as a PIC12F675 (8-bit microcomputer with A / D conversion function / flash memory) manufactured by Microchip Corporation. By monitoring the voltage at the voltage dividing points of the resistors R4 and R5, the lamp The voltage is detected, and the rated power of the lamp as a load is determined according to the detected value. For this purpose, the 7th pin is set as an A / D conversion input, and the lamp voltage value obtained from the voltage across the capacitor C2 is read. The 2nd and 3rd pins are set to binary output. Pin 1 is a power supply terminal, and pin 8 is a ground terminal.

  The control circuit 5 supplies the desired power to the lamp DL by controlling the switching element Q1 of the step-down chopper circuit 2. As described above, when the voltage of the electrolytic capacitor C1 is constant (about 300 V), the power supplied to the lamp as the load can be determined by adjusting the current value supplied from the power source. For example, when 70 W of electric power is supplied to the lamp, if 70 W / 300 V≈0.23 A is supplied from the capacitor C1, which is a DC power source, the load consumes approximately 70 W. Based on this principle, the current value supplied from the DC power source is detected by the current detection resistor R3, and the current value is adjusted by the error amplifier OP1.

  Specifically, the on / off operation of the switching element Q1 of the step-down chopper circuit 2 is adjusted by comparing the output voltage of the error amplifier OP1 with the triangular wave signal at the minus terminal of the comparator OP2, and the supplied power is adjusted. . FIG. 4 shows an operation for generating a drive signal for the switching element Q1 by the comparator OP2.

  4A shows the H / L output state of the 2nd pin of the microcomputer IC1, and FIG. 4B shows the voltage of the capacitor C4 applied to the negative terminal of the comparator OP2, FIG. 4C. The solid line indicates the reference voltage applied to the plus terminal of the comparator OP2, the broken line indicates the voltage of the capacitor C4, and the figure (d) indicates the output of the comparator OP2. The comparator OP2 and the error amplifier OP1 can be constructed at low cost with an IC or the like in which two operational amplifiers are incorporated in one package, and the control power is supplied from the voltage Vcc.

  When the second pin of the microcomputer IC1 is at the H level, the switching element Q8 is turned on, whereby the capacitor C4 is short-circuited and the accumulated charge is discharged. When the second pin of the microcomputer IC1 becomes L level, the switching element Q8 is turned off, so that the capacitor C4 is charged through the resistor R14 and the voltage rises. The voltage of the capacitor C4 is applied to the negative terminal of the comparator OP2. The output voltage of the error amplifier OP1 is applied as a reference voltage to the plus terminal of the comparator OP2. During the period when the voltage of the capacitor C4 is lower than the reference voltage, the output of the comparator OP2 becomes H level. Accordingly, the switching element Q1 is driven on and off at the frequency output from the second pin of the microcomputer IC1, and the pulse width thereof increases as the output voltage of the error amplifier OP1 increases. Therefore, by changing the reference voltage of the plus terminal of the error amplifier OP1, it is possible to adjust the current value (and hence the supplied power) supplied from the DC power supply.

  In order to simplify the circuit configuration in this circuit, a control signal for turning on / off the switching element Q8 is supplied from the second pin of the microcomputer IC1, but a high frequency oscillation circuit is provided separately from the microcomputer IC1. The switching element Q8 may be on / off controlled by the oscillation output.

  The chopper current flowing through the current detection resistor R3 is averaged by the resistor R6 and the capacitor C3, converted into a DC voltage, and applied to the inverting input terminal of the error amplifier OP1 via the input resistor R10. A feedback resistor R11 is connected between the inverting input terminal and the output terminal of the error amplifier OP1, and the amplification factor is determined by the ratio of the input resistor R10 and the feedback resistor R11. The voltage of the capacitor C5 is applied to the non-inverting input terminal of the error amplifier OP1.

  A PWM signal is output as a lamp power command value from the third pin of the microcomputer IC1. This PWM signal is a rectangular wave voltage whose pulse width changes according to the command value of lamp power. When the PWM signal becomes H level, the capacitor C5 is charged via the resistor R12, and when it becomes L level, the capacitor C5 passes through the resistor R12. C5 is discharged, and as a result, a DC voltage corresponding to the pulse width of the PWM signal is charged to the capacitor C5 as a target value for feedback control. As a result, the power supplied to the discharge lamp DL can be arbitrarily adjusted under the control of the microcomputer IC1, and an arbitrary lamp can be selected according to the detected value of the lamp voltage Vla (by referring to the memory table in the microcomputer IC1). Since power can be supplied, an arbitrary ballast characteristic (for example, the characteristic shown in FIG. 1 or the characteristic shown in FIG. 6 described later) can be realized.

  FIG. 1 shows a ballast characteristic used for discriminating a lamp type in the present embodiment. A solid line indicates a lamp voltage-lamp current characteristic, and a broken line indicates a lamp voltage-lamp power characteristic. The lamp is started with the ballast characteristic as shown in FIG. 1, and after the lamp is started, the lamp power type is determined by measuring the time for the lamp voltage to change from 30V to 40V.

  The time when the lamp voltage is changed from 30 V to 40 V can be detected by, for example, counting the number of A / D conversions (lamp voltage detection) of the microcomputer IC1. It can also be measured by using a built-in timer of the microcomputer IC1.

  FIG. 5 shows the result of measuring the time required for the lamp to start with the lighting device having the ballast characteristic shown in FIG. 1 and the lamp voltage at that time to change from 30V to 40V. In the figure, the solid line graph indicates the elapsed time at the initial start, and the diagonal line graph indicates the elapsed time at the restart. The target lamps are data of 5 to 6 lamps of Cerameta Premier S (manufactured by Matsushita Electric Industrial Co., Ltd.) with 35 W and 70 W color temperatures of 3000K, 3500K, and 4200K. From FIG. 5, if the time for the lamp voltage to change from 30V to 40V is determined as a threshold value, for example, about 3.0 seconds, 35 W and 70 W can be determined.

  In the present embodiment, control is performed so that the ballast characteristic in the lamp discrimination period, for example, the period in which the lamp voltage is 30 V to 40 V, becomes a constant power characteristic (for example, a constant power value of 30 W) as shown by a broken line in FIG. . As described above, the determination performance is further improved by determining the measurement of the time required for the lamp voltage to rise from 30 V to 40 V in the period of the substantially constant lamp power characteristic.

  With this ballast characteristic, the ramp voltage rise characteristic when the lamp is started is as shown in FIG. From FIG. 2, the ramp-up characteristic of the lamp voltage until the lamp voltage becomes stable is a linear function. Therefore, by discriminating a plurality of types of lamps using this ballast characteristic, it becomes possible to perform the discrimination more reliably.

(Embodiment 2)
This embodiment will be described with reference to FIG. In the first embodiment, as shown in FIG. 1, when determining the lamp rated power of 35 W and 70 W, the constant power value of the determination period is set to about 30 W. However, in this embodiment, two types of lamps are used. Among the rated powers, the smaller rated power value is set as the constant power value for the discrimination period. That is, the ballast characteristic in the lamp discrimination period (period in which the lamp voltage is 30 V to 40 V) is controlled to be a constant power characteristic (constant power value 39 W) as shown by the solid line in FIG. Then, the time required for the lamp voltage to change from 30 V to 40 V is measured, and if it is shorter than a predetermined time (for example, about 3 seconds), it is lit as it is with a constant power characteristic of 39 W (see the broken line in FIG. 6). . If the time required for the lamp voltage to change from 30 V to 40 V is longer than the predetermined time, the lamp power is increased and shifted to a constant power characteristic of 70 W (see the solid line in FIG. 6).

  By using such ballast characteristics, there are two types of constant power characteristics required for ballast. Therefore, it is possible to reduce circuit components and improve controllability. Furthermore, when the lamp power type is 35 W, it is not necessary to switch the ballast characteristic after lamp determination, so that fluctuations in light output are also suppressed.

(Embodiment 3)
FIG. 7 shows the ramp voltage rise characteristics of three 35 W and 70 W lamps of Cerameta Premier S (manufactured by Matsushita Electric Industrial Co., Ltd.) when the high pressure discharge lamp lighting device of the first embodiment is used. From FIG. 7, it can be seen that, for example, a lamp with a lamp voltage of less than 40 V 20 seconds after lighting can be reliably determined to be a 70 W lamp. Therefore, by adding the determination method of the third embodiment to the high pressure discharge lamp lighting device of each of the above embodiments, it is possible to more reliably determine the lamp type.

  The operation flow at that time is shown in FIGS. FIG. 8 shows the overall flow, and FIG. 9 shows the detailed flow of the discrimination processing. The configuration of the lighting device may be the same as in FIG.

  When the power is turned on in step # 1 in FIG. 8, a high voltage starting voltage is applied by the igniter circuit 4, and it is determined in step # 2 whether the lamp has started. Whether or not the lamp has started can be determined by the microcomputer IC1 by dividing and detecting the voltage across the capacitor C2, which is the output voltage of the step-down chopper circuit 2, which is substantially equal to the lamp voltage, by the resistors R4 and R5.

  When the discrimination process is started in step # 3, the process waits for discriminations A and B in FIG. 9 to be described later (# 4). When the discrimination process is finalized, the discrimination process is terminated (# 5). The output power is switched according to (# 6, # 7). Steps # 8 to # 10 in FIG. 8 are operations for performing rated lighting control according to the determination result after the determination process is completed.

  FIG. 9 is a detailed flow of the discrimination process, and corresponds to steps # 3 to # 5 in FIG.

  When the discrimination process is started in step # 11, control is performed so that a constant lamp current is obtained in step # 12, and measurement of time t1 is started in step # 13. Specifically, the variable t1 inside the microcomputer IC1 may be reset to 0, a timer interrupt at regular intervals may be permitted, and the variable t1 may be incremented each time the timer interrupt occurs.

  In steps # 14 and # 15, the process waits until the lamp voltage becomes Vla ≧ 30 V or the measured value of time t1 becomes 20 seconds or more.

  If t1 ≧ 20s before Vla ≧ 30V, the measurement of time t1 is terminated in step # 16. Specifically, the variable t1 in the microcomputer IC1 is reset to 0, and the timer interrupt is prohibited. This is to prevent re-determination of t1 ≧ 20 s in step # 23 described later.

  In step # 17, the lamp voltage is detected, and the detected value is set to Vla3. In step # 18, it is determined whether Vla3 <40V. If the lamp voltage is less than 40 V even after 20 seconds have elapsed from the start, it can be determined from FIG. 7 that the lamp is a 70 W lamp, so the process proceeds to step # 19, and the first determination result (determination A) is 70 W lamp. determine. In other cases, the process proceeds to step # 20 and the first determination result (determination A) is unknown.

  The same determination process as in steps # 15 to # 20 is also provided in steps # 23 to # 28, but the latter determination process is performed before V1 ≧ 30V before t1 ≧ 20s in the loop of steps # 14 and # 15. It is executed only when If step # 16 is passed once, t1 = 0 at that time, and the count of variable t1 stops. Therefore, when returning to step # 14 from step # 19 or # 20, t1 is passed through step # 15. Since it is = 0, it does not shift to step # 16, but waits for Vla ≧ 30 V in the loop of steps # 14 and # 15, and the result of discrimination A once confirmed is changed. No.

  When Vla ≧ 30V is satisfied in step # 14, the process proceeds to step # 21, and measurement of time t2 is started. Specifically, the variable t2 inside the microcomputer IC1 may be reset to 0, a timer interrupt at regular intervals may be permitted, and the variable t2 may be incremented each time the timer interrupt occurs.

  In step # 22, control of constant lamp power (for example, 30 W, see the broken line in FIG. 1) is set, and in step # 23, t1 ≧ 20 s, or in step # 29, the detected value of lamp voltage becomes Vla2 ≧ 40V. Wait for. If t1 ≧ 20s in step # 23, the operations of steps # 24 to # 28 (the same operations as described in steps # 15 to # 20) are executed only once, and then t1 = 0. Thus, the loop of steps # 22 → # 23 → # 29 is repeated.

  If Vla2 ≧ 40V in step # 29, the process proceeds to step # 30, and the measurement of time t2 is ended. Specifically, the timer interrupt may be prohibited while keeping the value of the variable t2. This variable t2 starts counting from t2 = 0 in step # 21 immediately after Vla ≧ 30 V in step # 14, and stops counting in step # 30 immediately after Vla2 ≧ 40 V in step # 29. Therefore, it corresponds to the time when the lamp voltage changes from 30V to 40V.

  In step # 31, it is determined whether or not the time t2 is less than 3 seconds. If t2 <3 s, it can be determined from FIG. 5 that the lamp is a 35 W lamp, so the second determination result (determination B) is determined to be a 35 W lamp in step # 32. If t2 ≧ 3 s, it can be determined from FIG. 5 that the lamp is a 70 W lamp, so the second determination result (determination B) is determined to be a 70 W lamp in step # 33. In step # 34, the determination result is confirmed, and the determination process in step # 5 in FIG. 8 ends.

  In step # 6 of FIG. 8, the first determination result (determination A) is preferentially referred to. If the determination A is 70 W, the process proceeds to 70 W rated lighting control in step # 8. If discrimination A is not 70 W, the second discrimination result (discrimination B) is referred to in step # 7. If discrimination B is 70 W, 70W rated lighting control in step # 9 is performed and if discrimination B is 35 W. Then, the process shifts to 35 W rated lighting control in step # 10.

  As described above, in the present embodiment, as a first determination method, the lamp voltage 20 seconds after the start is measured, and when the lamp voltage 20 seconds after the start is less than 40 V, it is determined as 70 W.

  As a second determination method, the time until the lamp voltage reaches 30V to 40V is measured, and when the required time from 30V to 40V is less than 3 seconds, it is determined as 35W. Moreover, when the time required from 30V to 40V exceeds 3 seconds, it is determined as 70W.

  In the present embodiment, the first determination result (determination A) is preferentially referred to, but the second determination result (determination B) may be preferentially referred to.

  Further, although the determination is made by combining the two measured values, it is also possible to determine only by the time required for the lamp voltage to rise from 30 V to 40 V. In that case, in step # 15 to step # 15 in FIG. It is only necessary to omit # 20, # 23 to # 28, and # 13.

(Embodiment 4)
FIG. 10 shows a structural example of a lighting fixture using the discharge lamp lighting device of the present invention. (A), (b) is an example applied to a spotlight, (c) is an example applied to a downlight. In the figure, 11 is an electronic ballast storing a circuit of a lighting device, and 12 is a high pressure discharge lamp. The lamp body 13 is a wiring. In any lighting fixture, a plurality of types of high-pressure discharge lamps such as 35 W and 70 W can be appropriately selected and mounted. A plurality of these lighting fixtures may be combined to construct an illumination system, and a plurality of different types of high-pressure discharge lamps may be used in combination depending on the required illuminance, emission color, design, and the like.

  In addition, a high-pressure discharge lamp lighting device that obtains light output by simply connecting the high-pressure discharge lamp and the ballast, an illumination system that uses a combination of multiple lighting fixtures with different ratings, and a lamp and ballast or reflector are required as appropriate. It is also possible to take the form of a lighting system composed of any number of combinations. Alternatively, it may be used in an illumination system in which the lamp and the light output unit are installed at positions separated from each other by using a means for conducting light, or in combination with other light sources.

It is a characteristic view which shows the ballast characteristic of the lighting device of Embodiment 1 of this invention. FIG. 2 is a characteristic diagram showing a rising characteristic of a lamp voltage when the lamp is started with the ballast characteristic of FIG. 1. It is a circuit diagram which shows the structure of the lighting device of Embodiment 1 of this invention. It is a wave form diagram which shows the output control operation | movement of the lighting device of Embodiment 1 of this invention. It is a figure which shows the result of having measured the characteristic of the lamp | ramp used as the load object of the lighting device of Embodiment 1 of this invention. It is a characteristic view which shows the ballast characteristic of the lighting device of Embodiment 2 of this invention. FIG. 6 is a characteristic diagram showing a rise characteristic of a lamp voltage when the lamp of FIG. 5 is started. It is a flowchart for operation | movement description of the whole lighting device of Embodiment 3 of this invention. It is a flowchart for detailed operation | movement description of the discrimination | determination process of the lighting device of Embodiment 3 of this invention. It is a perspective view which shows the external appearance of the lighting fixture of this invention. It is a characteristic view which shows the ballast characteristic of the high voltage | pressure discharge lamp lighting device of general rated power 70W. FIG. 12 is a characteristic diagram showing a rising characteristic of a lamp voltage when the lamp is started with the ballast characteristic of FIG. 11.

Explanation of symbols

DL High pressure discharge lamp (HID lamp)
2 Step-down chopper circuit 5 Control circuit 6 Discharge lamp discrimination circuit IC1 Microcomputer

Claims (6)

It has a power conversion circuit that converts power from a DC power source and supplies power to the high-pressure discharge lamp, and a lighting control circuit that controls the power supplied to the power conversion circuit. A discharge lamp lighting device for determining the type of the discharge lamp and lighting the high-pressure discharge lamp at a rated level, wherein the period for determining the type of the high-pressure discharge lamp is until the illuminance or lamp voltage of the discharge lamp is stabilized, and The type of the high-pressure discharge lamp depends on the time during which the high-voltage discharge lamp is lit with substantially constant lamp power and the lamp voltage changes from the first lamp voltage to the second lamp voltage larger than the first lamp voltage within the determination period. And a high pressure discharge lamp connected with the power selected based on the determination result is lit. 2. The discharge lamp lighting device according to claim 1, wherein the substantially constant lamp power value in the period for discriminating the type of the discharge lamp is smaller than the smallest power among the plurality of types of discharge lamp rated power. 2. The discharge lamp lighting device according to claim 1, wherein the substantially constant lamp power value in the period for discriminating the type of the discharge lamp is equal to the smallest power among a plurality of types of discharge lamp rated power. The type of the high-pressure discharge lamp is determined based on a time when the first lamp voltage changes to the second lamp voltage and a lamp voltage after a predetermined time has elapsed after the discharge lamp starts. Item 4. The discharge lamp lighting device according to any one of Items 1 to 3. The lighting fixture provided with the discharge lamp lighting device in any one of Claims 1-4. The lighting system containing the discharge lamp lighting device or lighting fixture in any one of Claims 1-5.

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