JP4671807B2 - Power supply for light source - Google Patents

Description

  A compact and economical power supply that does not cause abnormal phenomena such as stable lighting and extinction of discharge lamps such as high-pressure mercury vapor discharge lamps and metal halide lamps.

  Conventionally, a power supply device having a constant current characteristic as a power supply for a discharge lamp and a power supply having a characteristic of stabilizing a DC current after generating high-voltage high-frequency power when ignited and lighting it have been provided. It was. In the case of a discharge lamp for a projector, stable start-up, miniaturization, and economy are important, and a power source for a light source suitable for the purpose of use has been provided. There is the following Patent Document 1 as a document that discloses a power source for a light source. It consists of a starter that operates at startup and a lamp control circuit that keeps the power constant. "

  (Paragraph 0004) of the same document states that “when starting, a high voltage is applied to the lamp and the starter is operated to start glow discharge” “shift from glow discharge to initial arc discharge. "Low voltage of 10-50 volts" "This is often a special arc discharge rather than a thermal arc. This type of arc discharge also occurs when the lamp is turned on again." We need the ability to increase the output voltage instantaneously to shift to glow discharge. " In the same issue (paragraph 0008), the power supply device has characteristics that match the characteristics of the lamp as described above, “Since the power supply device cannot realize a steep voltage rise, the discharge lamp often goes off.” Therefore, the starter unit shown in FIG. 1 of Patent Document 1 (transcribed in FIG. 3 of this application specification) is expensive for the switch element S1, the high voltage transformer T1, the gap G1, and the high voltage transformer T2. The power supply device that required two sets of high voltage members to be attached was hindered from being reduced in size and weight.

“JP 2002-117990”, “Power Supply Device for Discharge Lamp”

  Miniaturization and weight reduction are strongly demanded for a power source device for a light source, and it has been a problem to construct a simplified circuit power source by a new constituent member having characteristics that match lamp characteristics.

  In order to solve the above-mentioned problems, two sets of high-voltage members, which are expensive members, were required. The following configuration was studied with a focus on creating a circuit having the same characteristics as one set. did.

According to a first aspect of the present invention, there is provided an input-side rectifier circuit connected to an AC input terminal, and a first reactor and a first diode connected in series through a smoothing capacitor having one terminal connected to the input-side rectifier circuit. A main power source comprising a DC-DC converter circuit, a secondary coil of a high-voltage pulse transformer connected in series to the DC-DC converter circuit, and an output terminal connected to a discharge lamp of a load in series with the secondary coil Lamp power supply unit that is a circuit,
Two units of a series connection body of a primary coil and a capacitor of the high voltage pulse transformer and a pulse power unit having a starter function formed by a parallel connection body of the capacitor series connection body and a trigger means such as a thyristor. A capacitor of the pulse power unit is connected to a connection point of the first reactor and the first diode via a time constant circuit, and a primary coil of the high-voltage pulse transformer of the pulse power unit is connected to the other end of the smoothing capacitor. A power source device for a light source characterized by being connected to a terminal.

  According to a second aspect of the present invention, the DC-DC converter circuit includes a first reactor for energy storage connected in series to a main circuit, a diode connected in series to the positive reactor and a positive terminal of a smoothing capacitor, and the first reactor. 2. A high power factor DC-DC converter circuit according to claim 1, wherein one terminal of a power factor correction circuit is connected to the diode connection point, and the other terminal of the power factor correction circuit is connected to the other terminal of the smoothing capacitor. A power source device for the light source was obtained.

  According to a third aspect of the present invention, in the DC-DC converter circuit, a switching element is connected in series via the first reactor connected in series with the main circuit, and a diode connected in series with the first reactor, and further connected in series with the second reactor. The light source power supply device according to claim 1, wherein the power source device is a DC-DC converter circuit to which one end of a secondary coil of the high-voltage pulse transformer is connected.

  According to a fourth aspect of the present invention, in the DC-DC converter circuit, a switching element is connected in series via the first reactor connected in series to the main circuit and a first diode connected in series to the first reactor, and further a second in series. DC connected to the reactor, the cathode of the second diode connected to the input terminal of the second reactor, and the second smoothing capacitor and the second switching element series body connected to the negative main circuit to the output terminal of the second reactor The light source power supply device according to claim 1, which is a DC converter circuit.

  As described above, in the past, the starter transformers T1 and T2, which are high-voltage members that required two sets, can be realized with a new concept and a set of pulse transformers (high-voltage members). As a result, it was possible to reduce the size and weight of the product, reducing the cost of the parts and the number of assembly steps, and making it cheaper.

  An embodiment of the present invention will be described with reference to the block diagram of FIG. The input-side rectifier circuit 1 is connected to the input terminal AC, and further connected to the DC-DC converter circuit 6 having a serially connected body of the first reactor 11 and the first diode 4, and to the DC-DC converter circuit 6. A high voltage pulse transformer secondary coil 7, a lamp power supply unit which is a power supply main circuit composed of a secondary coil 7 and an output terminal 17 to which a discharge lamp 26 as a load is connected in series; The primary coil 12 and the time constant circuit 15 are connected in series, and the time constant circuit 15 and a pulse power unit 16 formed of a trigger discharge circuit D such as a thyristor are provided. The primary coil 12 of the high-voltage pulse transformer is connected to the connection point P between the first reactor and the first diode via the time constant circuit 15, and the primary coil 1 It is connected to the other terminal of the smoothing capacitor 19. Since the power factor improving means 3 is connected between the connection point of the first reactor 11 with the first diode 4 and the other pole terminal of the smoothing capacitor 19, the power factor of the apparatus is improved. In the conventional starter shown in FIG. 3, two sets of high voltage transformers T1 and T2 and two sets of trigger means S1 and G1 each achieve the same operation.

  The operation of the block diagram will be described with reference to the circuit diagram of FIG. A DC-DC converter circuit 6 having a series connection body of a first reactor 11 and a first diode 4 connected to the input terminal AC through the connection point of the smoothing capacitor 19 and the input side rectifier circuit 1; A lamp power supply unit comprising a secondary coil 7 of a high-voltage pulse transformer connected in series to a DC converter circuit 6 and an output terminal 17 connected to a discharge lamp 26 of a load in series with the secondary coil 7 A circuit is formed.

  Two units: a series connection body of the primary coil 12 and the capacitor 25 of the high-voltage pulse transformer, and a pulse power unit 16 formed of a parallel connection body of the series connection body of the capacitor 25 and a trigger means 21 such as a thyristor. Is forming. A capacitor 25 of the pulse power unit 16 is connected to a connection point P between the first reactor 11 and the first diode 4 via a time constant resistor 15, and the primary coil 12 of the high voltage pulse transformer of the pulse power unit 16. Is connected to the different polarity terminal of the smoothing capacitor 19.

  The DC-DC converter circuit 6 includes a first reactor 11 for energy storage connected in series to a main circuit, and a diode 4 and a positive terminal of a smoothing capacitor 5 connected in series to the first reactor 11. One terminal of the power factor correction circuit is connected to the connection point P with the diode 4, and the other terminal of the power factor correction circuit is connected to the other terminal of the smoothing capacitor, and a part of the high power factor DC-DC converter circuit is connected. Form.

  The DC-DC converter circuit 6 has a second switching element 9 connected in series via a first diode 4 connected in series to the first reactor, and performs a step-down action. Further, the DC-DC converter circuit 6 is connected in series with a second reactor 13 for energy storage. The input terminal of the secondary coil 7 of the high voltage pulse transformer is connected.

  The DC-DC converter circuit 6 has a main circuit in which the cathode of the second diode 10 is connected to the input terminal of the second reactor 13, and the second capacitor 20 and the third switching element 14 are connected in series to the output terminal of the second reactor 13. A DC-DC converter circuit that is connected between the negative electrode and performs a boosting action is provided, and the boosting function and the step-down function are connected in series. In the lamp power supply unit having the DC-DC converter circuit, a second switching element 9 is connected in series via a first reactor 11 and a first diode 4 connected in series therewith, and further in series with a second reactor 13. One end of the secondary coil 7 of the high voltage pulse transformer to be connected is connected, and the other end of the secondary coil of the high voltage pulse transformer is connected to the negative output terminal of the input side rectifier circuit 1 via a discharge lamp.

  As described above, by configuring the power supply of the simplified circuit, expensive high-voltage members can be saved, contributing to resource saving and high industrial value.

It is a block diagram which shows one embodiment by this invention. It is a circuit diagram which shows one embodiment by this invention. It is a circuit diagram of the conventional apparatus (FIG. 1 of patent document 1).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Input side rectifier circuit 3 Power factor improvement means 4 1st diode 5 Smoothing capacitor 6 DC-DC converter
7 Secondary coil of pulse transformer 8 First switch element 9 Second switch element 10 Second diode 11 First reactor 12 Primary coil of pulse transformer 13 Second reactor 14 Third switch element 15 Time constant circuit 16 Pulse power unit 17 Output terminal 18 Diode 19 Smoothing capacitor 20 Capacitor 21 Trigger means (thyristor)
22 Diode 23 Diode 24 Capacitor 25 Capacitor 26 Discharge lamp AC Input terminal P Connection point D Trigger discharge circuit T1, T2 High voltage transformer

Claims (4)

DC-DC having an input side rectifier circuit connected to an AC input terminal, and a series connection body of a first reactor and a first diode connected via a connection point of a smoothing capacitor having one terminal connected to the input side rectifier circuit A lamp power supply unit comprising: a converter circuit; a secondary coil of a high-voltage pulse transformer connected in series to the DC-DC converter circuit; and an output terminal connected to a discharge lamp of a load in series with the secondary coil; A series connection body of a primary coil and a capacitor of the high-voltage pulse transformer, and a pulse power unit formed by a parallel connection body of the capacitor series connection body and a trigger means such as a thyristor, A capacitor of the pulse power unit is connected to a connection point between the first reactor and the first diode through time constant means, and the pulse power unit is connected. DOO of the high-voltage pulse transformer primary coil light source power supply device characterized in that it is connected to the other terminal of the smooth capacitor.
In the DC-DC converter circuit, a first reactor for energy storage connected in series to a main circuit, a diode connected in series to this and a positive terminal of a smoothing capacitor are connected, and the first reactor and the diode connection point are connected. 2. The power source device for a light source according to claim 1, wherein one terminal of the power factor correction circuit is connected, the other terminal of the power factor correction circuit is connected to the other terminal of the smoothing capacitor, and is a high power factor DC-DC converter circuit.
The DC-DC converter circuit includes the first reactor connected in series to a main circuit, a switching element connected in series via a diode connected in series to the first reactor, and the high-voltage pulse transformer connected in series to a second reactor. The power supply device for light sources of Claim 1 which is a DC-DC converter circuit to which the end of the secondary coil of this is connected.
  In the DC-DC converter circuit, a switching element is connected in series via the first reactor connected in series to the main circuit, and a first diode connected in series with the first reactor, and further a second reactor is connected in series. This is a DC-DC converter circuit in which the cathode of the second diode is connected to the input terminal of the 2-reactor, and the second smoothing capacitor and the second switching element series body are connected to the negative main circuit at the output terminal of the second reactor. The power supply device for a light source according to claim 1.

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