JP4608646B2 - Discharge lamp lighting device and lighting fixture - Google Patents

Description

The present invention relates to a discharge lamp lighting device and a lighting fixture for lighting a discharge lamp that boosts a DC voltage obtained by rectifying an AC power supply voltage with a boost chopper circuit and converts an output of the boost chopper circuit into a high frequency with an inverter circuit.

  2. Description of the Related Art Conventionally, there is known a discharge lamp lighting device that boosts a DC voltage obtained by rectifying an AC power supply voltage with a boost chopper circuit and converts the output of the boost chopper circuit into a high frequency with an inverter circuit to light the discharge lamp. The discharge lamp lighting device supplies a substantially flat DC voltage to the inverter circuit without reducing the input power factor due to the action of the boost chopper circuit and without causing a large distortion in the input current. The luminous efficiency can be increased.

  The boost chopper circuit has a control boost chopper control circuit, the inverter circuit has a control inverter control circuit, and each of the boost chopper control circuit and the inverter control circuit has a power supply circuit. .

  However, the output of the step-up chopper circuit has a problem that the output changes greatly and the voltage fluctuates when the discharge lamp is lit and not lit.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a discharge lamp lighting device that can reduce voltage fluctuations regardless of whether the discharge lamp is lit or not.

A discharge lamp lighting device according to claim 1, wherein a DC voltage obtained by rectifying an AC power supply voltage is boosted by a boost chopper circuit, an output of the boost chopper circuit is converted into a high frequency AC voltage by an inverter circuit, and the discharge lamp is lit. In a lamp lighting device, a step-up chopper control circuit that controls the step-up chopper circuit, an inverter control circuit that controls the inverter circuit, and the step-up chopper that is fed from the output side of the step-up chopper circuit via a resistor and a switch element A startup circuit for the control circuit and the inverter control circuit, and before the operation of the boost chopper control circuit, the power is supplied to the boost chopper control circuit and the inverter control circuit via the startup circuit, and the boost chopper circuit after operation, the force said starting circuit is interrupted by the switching element With not supplied to power the boost chopper control circuit and the inverter control circuit from the circuit, the power output of the inverter circuit, wherein the boost chopper control circuit and the inverter control circuit is connected a different route from that of the starting circuit It operates as.

  According to a second aspect of the present invention, there is provided a lighting fixture in which the discharge lamp lighting device according to the first aspect is housed in a fixture main body, and a discharge lamp attached to the fixture main body is turned on.

  The discharge lamp lighting device according to claim 1 and the lighting fixture according to claim 2 having the lighting device supply power to the boost chopper control circuit and the inverter control circuit via the start-up circuit before the operation of the boost chopper control circuit. After operation of the boost chopper circuit, the boost chopper control circuit is cut off by the start-up circuit and the inverter circuit is used as a power source, so that voltage fluctuation can be reduced regardless of whether the discharge lamp is lit or not lit. , Power loss can be reduced.

  The discharge lamp lighting device according to claim 1 and the lighting fixture according to claim 2 having the lighting device supply power to the boost chopper control circuit and the inverter control circuit via the start-up circuit before the operation of the boost chopper control circuit. After operation of the boost chopper circuit, the boost chopper control circuit is cut off by the start-up circuit and the inverter circuit is used as a power source, so that voltage fluctuation can be reduced regardless of whether the discharge lamp is lit or not lit. , Power loss can be reduced.

  Hereinafter, an embodiment of a lighting fixture of the present invention will be described with reference to the drawings. In FIG. 2, reference numeral 1 denotes an instrument body formed in a metal hollow box shape, and a reflecting surface 2 is formed on the lower surface of the instrument body 1. The lamp sockets 3 and 3 are attached to face each other, and a straight tube type fluorescent lamp FL as a discharge lamp is electrically and mechanically sandwiched and connected between the lamp sockets 3 and 3. Further, an electrical circuit 5 for lighting the fluorescent lamp FL is housed in the instrument body 1.

  Next, an embodiment of the circuit configuration of the electric circuit 5 will be described with reference to FIG. The inverter circuit 13 shown in FIG. 1 is a separately excited type, and field effect transistors Q2 and Q3 are connected between both terminals of the boost chopper circuit 12, and a capacitor C11 is connected between the source and drain of the field effect transistor Q2. The input winding Tr3a of the transformer Tr3 and the capacitor C12 are connected.

  Further, the input winding Tr4a of the transformer Tr4 and the capacitor C13 are connected between the output terminals of the inverter circuit 13, and connected to the discharge lamp FL via the capacitor C14. The filament of the discharge lamp FL is connected to the transformer Tr4. It is connected to the filament windings Tr4b and Tr4c.

  Further, the output winding Tr3b of the transformer Tr3 is connected to the inverter control circuit 15 via the contacts A and B and via the capacitors C15 and C16 and the diodes D4 and D5. The inverter control circuit 15 To the gates of the field effect transistors Q1 and Q2. Further, the inverter control circuit 15 is connected to a choke coil L1 via a diode D1, and is connected to a starting resistor R7. Furthermore, the booster chopper control circuit 14 is connected through the diode D4 to the diode D6.

  In the circuit shown in FIG. 1, even when the boost chopper circuit 12 does not operate and is not boosted, the inverter is operated by the starting resistor R7, the inverter circuit 13 is controlled, and high frequency alternating current is generated. In addition, the inverter circuit 13 can be started quickly, and can be lit even when an AC power supply having a rated voltage or lower is connected.

  In this case, since the boost chopper control circuit 14 of the boost chopper circuit 12 and the inverter control circuit 15 of the inverter circuit 13 both perform rectification and smoothing using the output of the inverter circuit 13 as a power source, the circuit configuration is In addition, when the inverter circuit 13 stops oscillating, no voltage is supplied to either the step-up chopper control circuit 14 or the inverter control circuit 15, so that power saving can be achieved.

  Furthermore, another embodiment will be described with reference to FIG. In the embodiment shown in FIG. 3, in the circuit shown in FIG. 1, a switch SW1 for connecting and closing the start-up resistor R7 is connected to the diode D7 for full-wave rectification of the high-frequency alternating current of the output winding Tr3b of the transformer Tr3. The resistor R7 is connected in series.

  An embodiment will be described with reference to FIG. In the embodiment shown in FIG. 4, an oscillation stop circuit 17 that is an oscillation stop means of the inverter control circuit 15 is connected to the inverter control circuit 15. Further, a pulse width control (PWM) signal is connected to the full-wave rectifier circuit 18, and the output terminal of the full-wave rectifier circuit 18 is connected to the oscillation stop circuit 17 via a resistor R 7 and a photocoupler 19. Then, all the lights are turned on when the pulse off is 100%, the dimming is turned on when the pulse is 20%, and the light is stopped when it is 0%.

  The output winding Tr3b of the transformer Tr3 is connected to the step-up chopper control circuit 14 via the capacitor C16, the diodes D8 and D9, and the capacitor C17. That is, the output of the output winding Tr3b is rectified and smoothed using the output of the output winding Tr3b as a power source and supplied to the boost chopper control circuit 14.

  When a stop pulse with an off ratio of 0% is input, the oscillation stop circuit 17 stops oscillation of the inverter control circuit 15 and stops the inverter circuit 13. When the output of the inverter circuit 13 is stopped, the supply of power to the boost chopper control circuit 14 is also stopped, the boost chopper control circuit 14 does not operate, and the boost chopper circuit 12 also stops the boost operation.

  Therefore, power consumption can be reduced when the discharge lamp FL is turned off, and heating of the boost chopper circuit 12 when the discharge lamp FL is turned off can be prevented.

  Further, in the circuit shown in FIG. 4, even when the power of the boost chopper control circuit 14 is not taken from the inverter circuit 13, the oscillation stop circuit 17 serving as the oscillation stop means is connected to the inverter control circuit 15 and the boost chopper control circuit 14, When the discharge lamp FL is turned off, the oscillation stop circuit 17 stops the oscillation of the inverter control circuit 15 and the boost chopper control circuit 14 so that both the inverter circuit 13 and the boost chopper circuit 12 are stopped when the discharge lamp FL is turned off. It is also possible to save power.

  Furthermore, another embodiment will be described with reference to FIG. In the embodiment shown in FIG. 5, a full-wave rectifier circuit 11 is connected to a commercial AC power source E, a boost chopper circuit 12 is connected to the full-wave rectifier circuit 11, and an inverter circuit 13 is connected to the boost chopper circuit 12. Has been.

  The boost chopper circuit 12 includes a choke coil L1, a field effect transistor Q1, a diode D1, and capacitors C21 and C22, and the coil L2 is magnetically coupled to the choke coil L1. The inverter circuit 13 is connected to field effect transistors Q2 and Q3, a coil L3, and a capacitor C12, and a discharge lamp FL is connected to the inverter circuit 13 via a capacitor C14.

  The coil L2 is connected to the step-up chopper control circuit 14 via a rectifier diode D11, a resistor R11, a constant voltage Zener diode ZD1, and a capacitor C23, and a rectifier diode D12, a resistor R12, It is connected to the inverter control circuit 15 through a Zener diode ZD2 for constant voltage and a capacitor C24.

Further, a starting circuit 21 including a resistor R7 and a transistor Q4 is connected to the choke coil L1 via the diode D1, and this starting circuit 21 is connected to the boost chopper control circuit 14 and the inverter control circuit 15 via the diode D13 and the diode D14. It is connected to the.
When the boost chopper circuit 12 and the inverter circuit 13 are started, the transistor Q4 is turned on to supply power to the boost chopper control circuit 14 and the inverter control circuit 15 via the resistor R7. After the discharge lamp FL is turned on, The transistor Q4 is turned off, the output from the coil L2 of the boost chopper circuit 12 is rectified and smoothed, and power is supplied to the boost chopper control circuit 14 and the inverter control circuit 15.

  Thus, when the boost chopper circuit 12 and the inverter circuit 13 are started, the start circuit 21 supplies power to the boost chopper control circuit 14 and the inverter control circuit 15 via the resistor R7, and the boost chopper circuit 12 and the inverter circuit 13 After startup, power is supplied to the boost chopper control circuit 14 and the inverter control circuit 15 using the power from the coil L2 of the boost chopper circuit 12, so that the voltage fluctuation is small and the power supply efficiency can be improved.

  Another embodiment will be described with reference to FIG. In the embodiment shown in FIG. 6, a full-wave rectifier circuit 11 is connected to a commercial AC power source E, a boost chopper circuit 12 is connected to the full-wave rectifier circuit 11, and an inverter circuit 13 is connected to the boost chopper circuit 12. ing.

  The boost chopper circuit 12 includes a choke coil L1, a field effect transistor Q1, a diode D1, and capacitors C21 and C22. The inverter circuit 13 is connected to field effect transistors Q2 and Q3, an input winding Tr3a of a transformer Tr3, and a capacitor C12, and a discharge lamp FL is connected to the inverter circuit 13 via a capacitor C14.

  An inverter control circuit 15 is connected to the output winding Tr3b of the transformer Tr3, and a boost chopper control circuit 14 is connected to the inverter control circuit 15 via a switch SW2. Further, the inverter control circuit 15 is connected to the output winding Tr3b of the transformer Tr3b via a rectifying diode D11.

  Further, the inverter control circuit 15 has a circuit as shown in FIG.

  A ramp voltage detection circuit 22 is connected to the diode D11. The ramp voltage detection circuit 22 is connected to the base of the transistor Q5 via the diode D12, the capacitor C25, and the resistors R15, R16, and R17, and the collector of the transistor Q5. Is connected to the control circuit power source 23, and the emitter is grounded.

  The output detection circuit 24 is connected to one input terminal of the operational amplifier OP1 together with the ramp voltage detection circuit 22, and the reference voltage source E1 is connected to the other input terminal. The output terminal of the operational amplifier OP1 is connected to the capacitor C26, the resistor R18, and the base of the transistor Q6. The emitter of the transistor Q6 is grounded, and the collector is connected to the Vf converter 25 via a resistor R19. The resistor R20 and the capacitor C27 are connected to the Vf converter 25.

  Then, at the time of soft start at the start of the discharge lamp FL after the boost chopper circuit 12 and the inverter circuit 13 are started, as shown in FIG. 8, the transistor Q5 is turned on, the switch SW2 is turned off, and the boost chopper is turned on. The inverter circuit 13 is activated in a low voltage state without supplying power to the control circuit 14 and without operating the boost chopper circuit 12. Further, after the discharge lamp FL is turned on after the soft start is finished, the transistor Q5 is turned on, the switch SW2 is closed, the boost chopper circuit 12 is operated, and the boosted voltage is supplied to the inverter circuit 13.

  In this way, at the time of soft start of the discharge lamp FL, the boost chopper circuit 12 is not operated, and a low voltage is supplied to the inverter circuit 13, thereby reducing the stress of the voltage effect transistor Q1 of the inverter circuit 13.

  Furthermore, another embodiment will be described with reference to FIG. In FIG. 9, E is a commercial AC power source. A full-wave rectifier circuit 11 is connected to the commercial AC power source E via a filter transformer Tr <b> 1, and a smoothing circuit is provided between the output terminals of the full-wave rectifier circuit 11. A capacitor C1 is connected, and these constitute a DC power supply 10. Further, a boost chopper circuit 12 is connected to the DC power source 10, and an inverter circuit 13 is connected to the boost chopper circuit 12.

  The boost chopper circuit 12 is connected to a choke coil L1, a field effect transistor Q1, a freewheeling diode D1, a capacitor C2, and a resistor R1.

  Further, the inverter circuit 13 is self-excited, and two field effect transistors Q2 and Q3 are connected as switching elements between the output terminals of the boost chopper circuit 12, and a resistor R2 and a resistor R2 are connected in parallel to these field effect transistors Q2 and Q3. A series circuit of a capacitor C3 and a series circuit of voltage dividing capacitors C4 and C5 are connected, and a diode D2 is connected between the connection point of the resistor R2 and the capacitor C3 and the source of the field effect transistor Q2, and the resistor R2 and A diac Da1 is connected between the connection point of the capacitor C3 and the gate of the field effect transistor Q2.

  One end of the input winding Tr2a of the saturable transformer Tr2 is connected between the source of the field effect transistor Q2 and the drain of the field effect transistor Q3. Further, a resistor R3 and a resistor R4, an output winding Tr2b of a saturable transformer Tr2, and a series circuit of a capacitor C6 are connected in parallel between the gate and source of the field effect transistor Q2. Between the gate and source of the field effect transistor Q3, a resistor R5 and a resistor R6, an output winding Tr2c of a saturable transformer Tr2, and a series circuit of a capacitor C7 are connected in parallel. Further, a discharge lamp FL is connected between the other end of the input winding Tr2a of the saturable transformer Tr2 and the connection point of the capacitors C4 and C5 via the input winding Tr3a of the transformer Tr3. A capacitor C8 for starting is connected to FL.

  Further, the output winding Tr3 of the transformer Tr3 is connected to a boost chopper control circuit 14 composed of an IC or the like via a capacitor C9, a rectifying diode D3 and a smoothing capacitor C10. The booster chopper circuit 12 is connected to the gate of the field effect transistor Q1, and the booster chopper control circuit 14 performs chopper control of the field effect transistor Q1.

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

  First, the AC from the commercial AC power source E is full-wave rectified by the full-wave rectifier circuit 10, smoothed by the capacitor C1, and boosted by the step-up chopper circuit 12 by the chopper of the field-effect transistor Q1 by the boost chopper control circuit 14. The inverter circuit 13 converts the frequency into a high frequency. The step-up chopper control circuit 14 operates using the output of the inverter circuit 13 with the transformer Tr3, the capacitor C9, the diode D3, and the capacitor C10 as a DC power supply.

  Further, the inverter circuit 13 operates at a voltage not more than 2 times the square root of the voltage across the commercial AC power supply E, and as shown in FIG. 10, the start-up time for oscillating the inverter circuit 13 is shortened. Increase the rise time of the circuit 13. The boost chopper circuit 12 improves the starting performance of the inverter circuit 13 when the voltage is low.

It is a circuit diagram which shows the Example of the discharge lamp lighting device of this invention. It is a perspective view which shows the external appearance of one Embodiment of a lighting fixture same as the above. It is a circuit diagram which shows the discharge lamp lighting device of another Example same as the above. It is a circuit diagram which shows one Embodiment of a discharge lamp lighting device same as the above. It is a circuit diagram which shows the discharge lamp lighting device of another Example same as the above. It is a circuit diagram which shows the discharge lamp lighting device of another Example same as the above. It is a circuit diagram which shows a part of inverter control circuit same as the above. It is a graph which shows the operation | movement at the time of a soft start same as the above. It is a circuit diagram which shows the discharge lamp lighting device of another Example same as the above. It is a graph which shows the relationship between DC voltage and time same as the above.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Instrument body, 10 ... DC power supply, 12 ... Boost chopper circuit, 13 ... Inverter circuit, 14 ... Boost chopper control circuit, 15 ... Inverter control circuit, 21 ... Start-up circuit, E ... AC power supply, FL ... Discharge lamp, R7 …resistance.

Claims (2)

In a discharge lamp lighting device that boosts a DC voltage obtained by rectifying an AC power supply voltage with a boost chopper circuit, converts an output of the boost chopper circuit into a high-frequency AC voltage with an inverter circuit, and turns on the discharge lamp.
A step-up chopper control circuit for controlling the step-up chopper circuit;
An inverter control circuit for controlling the inverter circuit;
A start-up circuit for the boost chopper control circuit and the inverter control circuit that are fed from the output side of the boost chopper circuit via a resistor and a switch element ;
Before the boost chopper control circuit operates, power is supplied to the boost chopper control circuit and the inverter control circuit via the start circuit, and after the boost chopper circuit operates, the start circuit is shut off by a switch element. The power from the startup circuit is not supplied to the boost chopper control circuit and the inverter control circuit, and the boost chopper control circuit and the inverter control circuit are connected through a path different from the startup circuit . A discharge lamp lighting device that operates using an output as a power source.   A discharge lamp lighting device according to claim 1 is housed in a fixture body, and a discharge lamp attached to the fixture body is turned on.

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