JPH06315269A - Device for lighting discharge lamp - Google Patents

Abstract

PURPOSE:To provide a device of increased input power factor and low harmonic noise for lighting a discharge lamp. CONSTITUTION:A charging capacitor 26 is charged with a pulsating flow outputted from a rectifier circuit 23 through a coil 25 and isolation diode 25 and, when one switching element 31 is turned on by the driving signal of a switch drive control circuit 33, a high-frequency load current is made to flow to a discharge lamp load circuit 40 and coupling capacitor 28 based on the charging voltage of the capacitor 26. When the other switching element 32 is turned on, a high-frequency load current is made to flow to a coupling capacitor 27, the load circuit 40, and th element 32 based on a counter electromotive force generated across a coil 24 connected to the positive output terminal of the rectifier circuit 23 and, at the same time, the capacitor 26 is charged through the isolation diode 25.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a discharge lamp lighting device for lighting a discharge lamp, for example, and more particularly to a discharge lamp lighting device capable of outputting a high frequency voltage having a high input power factor and few power source harmonics.

[0002]

2. Description of the Related Art FIG. 17 is a circuit diagram of a conventional discharge lamp lighting device, and FIG. 18 is a waveform diagram of an input voltage and an input current of the discharge lamp lighting device. In the figure, 1 is an AC power supply, 2 is a rectifying circuit composed of a diode bridge for rectifying the AC power supply 1, and 3 is a smoothing capacitor 3 connected between the output terminals of the rectifying circuit 2. The switching elements 4 and 5 connected in series with each other are connected in parallel to the smoothing capacitor 3. For the purpose of supplying a regenerative current to these switching elements 4 and 5, the diodes 6 and 7 are equivalently antiparallel to each other.
Are connected. Reference numeral 8 is a switch control circuit for alternately driving the switching elements 4 and 5 by high frequency. A coupling capacitor 9, a current limiting inductance element 10 and a discharge lamp 12 are connected in series between the connection point of the switching elements 4 and 5 and the ground portion of the rectifier circuit 2. A capacitor 11 is connected in parallel to the discharge lamp 12.

The conventional discharge lamp lighting device is constructed as described above. For example, the switching elements 4 and 5 are alternately turned on and off at a certain switching frequency by the switch control circuit 8.
When turned off, high-frequency power from the connection point of the switching elements 4 and 5 is coupled through the coupling capacitor 9 and the current limiting inductance element 10 to the discharge lamp 12 that is a load element.
Supply to. The capacitor 11, the inductance element 10 and the capacitor 9 which are connected in parallel to the discharge lamp 12 constitute a series resonance circuit, and a high voltage necessary for discharging is generated from both ends of the capacitor 11 to turn on the discharge lamp 12. I am letting you. A technique which is substantially the same as the above-mentioned conventional example is disclosed in JP-A-58-209896, and a technique using the conventional example as a basic circuit is disclosed in JP-A-3-283297.

[0004]

The conventional discharge lamp lighting device is of the capacitor input type as described above, and the power supply input current has a pulse-like sharp shape as shown in FIG. There is a problem that the power factor decreases and the power source harmonics increase. By the way, there is a method of using a choke input type smoothing circuit in order to increase the power factor of the input in the rectifying and smoothing circuit. However, if the choke input type is used, the size of the choke becomes large and heavy. Further, the loss due to this choke is large, and there is a new problem that it is not suitable for high efficiency and miniaturization of the device.

The present invention has been made in order to solve such problems, and it is possible to increase the input power factor, reduce the power source harmonics, and further reduce the size, efficiency and cost. An object is to obtain a discharge lamp lighting device.

[0006]

A first aspect of the present invention provides a rectifying circuit for full-wave rectifying the alternating current of an alternating current power source, a charging capacitor for charging the output of the rectifying circuit through a coil and a separation diode, and the charging capacitor. A pair of serially connected switching elements connected in parallel, a switch drive control circuit that outputs a high-frequency drive signal to each of the pair of switching elements, a connection point between the coil and the separation diode, and a negative side output terminal of the rectifier circuit. A pair of serially connected coupling capacitors provided between the pair of switching elements, a discharge lighting load circuit provided between the connection point of the pair of switching elements and the connection point of the pair of coupling capacitors, and the pair of One of the coupling capacitors is connected in parallel via a separation diode, and the other is directly connected in parallel with a pair of serially connected diodes. The switch drive control circuit comprises a drive signal whose frequency is changed in response to an increase or decrease in the output voltage or the input current of the rectifier circuit within each half cycle period of the AC power supply, or the amplitude of each half cycle of the AC power supply. It outputs at least one of a drive signal that is changed in a wide and narrow manner so as to contradict the increase or decrease of the output voltage or the input current of the rectifier circuit within the period.

A second aspect of the invention is a rectifying circuit for full-wave rectifying the alternating current of an alternating current power source, a charging capacitor for charging the output of the rectifying circuit via a coil and a separation diode, and a pair of parallelly connected to the charging capacitor. A switching element connected in series, a switch drive control circuit that outputs a high-frequency drive signal to each of the pair of switching elements, a pair of series-connected coupling capacitors connected in parallel to the charging capacitor, and the pair of switching elements. A discharge lighting load circuit provided between the connection point of the element and the connection point of the pair of coupling capacitors, and a voltage supply line connecting the connection point of the coil and the separation diode and the connection point of the pair of switching elements. It is equipped with.

A third aspect of the invention is a rectifying circuit for full-wave rectifying the alternating current of an alternating current power source, a partial smoothing circuit for charging the output of the rectifying circuit via a coil, and a pair of series connected in parallel to the partial smoothing circuit. A connected switching element, a switch drive control circuit that outputs a high-frequency drive signal to each of the pair of switching elements, a discharge lighting load circuit in which one terminal is connected to the connection point of the pair of switching elements, and It is provided with a coupling capacitor connected between the other terminal of the discharge lighting load circuit and the high potential side of the switching element.

A fourth aspect of the present invention provides a rectifying circuit for full-wave rectifying the alternating current of an alternating current power source, a pair of series-connected coupling capacitors connected in parallel to the positive and negative output terminals of the rectifying circuit, and a positive and negative output terminal of the rectifying circuit. A pair of switching elements connected in series connected in parallel via a separation diode, a switch drive control circuit for outputting a high-frequency drive signal to the pair of switching elements, a connection point of the pair of switching elements and the pair Of the discharge lighting load circuit provided between the connection point of the coupling capacitor and the coil connected to the connection point of the pair of switching elements via a diode, and the coil and the low potential side of the switching element. A charging capacitor connected in between, and a diode connected between the coil and the high potential side of the switching element. Is shall.

A fifth aspect of the present invention is a rectifier circuit for full-wave rectifying the alternating current of an alternating current power source, a pair of series-connected coupling capacitors connected in parallel to the positive and negative output terminals of the rectifier circuit via a coil, and the above-mentioned pair of capacitors. A pair of serially connected switching elements connected in parallel to the coupling capacitor via a separation diode, a switch drive control circuit for outputting high-frequency drive signals to the pair of switching elements, and a connection point of the pair of switching elements. And a discharge lighting load circuit provided between the connection point of the pair of coupling capacitors,
A diode connected to the connection point of the pair of switching elements, a charging capacitor connected between the diode and the high potential side of the switching element, and between the coil and the low potential side of the switching element. And a diode connected between the positive side output terminal of the rectifier circuit and the connection point of the pair of switching elements.

According to a sixth aspect of the present invention, a rectifying circuit for full-wave rectifying the alternating current of an alternating current power source, a charging capacitor for charging the output of the rectifying circuit via a separation diode, and a pair of series-connected parallel-connected to the charging capacitor. Switching element, a switch drive control circuit for outputting a high-frequency drive signal to each of the pair of switching elements, a coil connected to a connection point of the pair of switching elements, and a low potential side of the coil and the switching element. A discharge lighting load circuit in which a capacitor provided in series is connected in series, and a capacitor connected between the connection point of the coil and the discharge lighting load circuit and the positive side output terminal of the rectifier circuit. It will be.

In a seventh aspect of the present invention, the switch drive control circuit according to the first to sixth aspects of the present invention changes the frequency in response to an increase or a decrease in the output voltage or the input current of the rectifier circuit within each half cycle period of the AC power supply. The drive signal or the amplitude is varied within a wide range so as to contradict the increase or decrease of the output voltage or the input current of the rectifier circuit in each half cycle period of the AC power supply, and at least one of the drive signals is output.

[0013]

In the first aspect of the invention, the pulsating current output from the rectifier circuit is charged into the charging capacitor through the coil and the separation diode, and when one of the switching elements is turned on by the drive signal of the switch drive control circuit, the charging capacitor is charged. High-frequency load current flows through the discharge lamp load circuit and the coupling capacitor based on the charging voltage of, and when the other switching element is turned on, the coupling capacitor is generated based on the counter electromotive voltage generated in the coil connected to the positive side output terminal of the rectifier circuit. , The discharge lamp load circuit, because the high-frequency load current flows through the switching element and the charging capacitor is charged through the separation diode, the coupling capacitor, the discharge lamp load circuit, and the discharge lamp load circuit are generated by the counter electromotive voltage generated in the coil. Each time a high-frequency load current flows through the switching element, the AC power supply The input current flows against the flow voltage, and the input current also flows when the instantaneous value of the pulsating current of the rectifier circuit is low or near the peak value, so the input current waveform approaches the input voltage waveform and the input power factor is high. As a result, power supply harmonics decrease.

Further, the switch drive control circuit has a drive signal whose frequency is changed in response to an increase or decrease of the output voltage or the input current of the rectifying circuit within each half cycle period of the AC power supply, or the amplitude of each half cycle of the AC power supply. Since the output voltage of the rectifier circuit or at least one of the drive signals changed in a wide range so as to contradict the increase or decrease of the input current is output within the period, the frequency of the drive signal is high when the output voltage of the rectifier circuit is high, and the output voltage is high. When it is low, the frequency of the drive signal becomes low, and the amplitude of the drive signal also narrows accordingly when the output voltage is high, or the amplitude of the drive signal changes depending on whether the output voltage of the rectifier circuit is high or low. The step-up ratio to the capacitor is reduced and the load current is also suppressed to a low level. Ripple current is also reduced.

In the second invention, the pulsating current output from the rectifying circuit is charged into the charging capacitor through the coil and the separation diode, and when one of the switching elements is turned on by the drive signal of the switch drive control circuit, the charging capacitor is charged. High-frequency load current flows through the switching element, discharge lamp load circuit, and coupling capacitor based on the charging voltage of, and when the other switching element is turned on, the counter electromotive voltage generated in the coil connected to the positive output terminal of the rectifier circuit. Based on the above, the high-frequency current is made to flow to the switching element via the voltage supply line without flowing to the discharge lamp load circuit.Therefore, every time a high-frequency current flows to the switching element due to the back electromotive force generated in the coil. The input current flows against the AC voltage of the AC power supply, and the input current is the pulsating current of the rectifier circuit. To flow in addition to the vicinity or when the peak value instantaneous value is low, the input current waveform approaches the input voltage waveform, the power supply harmonic is reduced with the input power factor becomes higher.

In the third invention, the pulsating current output from the rectifying circuit is charged in the partial smoothing circuit via the coil,
When one switching element is turned on by the drive signal of the switching drive control circuit, a high-frequency load current flows through the coupling capacitor and the discharge lamp load circuit based on the charging voltage of the partial smoothing circuit, and when the other switching element is turned on, that switching Since the high frequency current flows through the discharge lamp load circuit based on the voltage charged in the capacitor connected to the element, the high frequency load current flows through the discharge lamp load circuit due to the voltage charged in the partial smoothing circuit. The input current flows for each AC voltage of the AC power supply every time, and since the input current also flows when the instantaneous value of the pulsating current of the rectifier circuit is low or other than near the peak value, the input current waveform approaches the input voltage waveform, As the input power factor increases and the power supply harmonics decrease, the voltage charged in the partial smoothing circuit is output from the rectifier circuit. Since the one-half of the voltage, requires the withstand voltage of the switching element is low.

In the fourth invention, the pulsating current output from the rectifying circuit is charged by the pair of coupling capacitors, and the pulsating current output from the rectifying circuit is output when one of the switching elements is turned on by the drive signal of the switch drive control circuit. The current is charged into the charging capacitor through the separation diode, its switching element, and the series circuit of the diode and the coil, and at the same time, a high frequency current flows through the discharge lamp load circuit and the coupling capacitor, and when the other switching element is turned on, the coupling capacitor Since high frequency load current is made to flow to the discharge lamp load circuit and switching element based on the voltage, every time a high frequency current flows to the switching element, discharge lamp load circuit and coupling capacitor, input is made to the AC voltage of the AC power supply. A current flows, and the input current is low when the pulsating current of the rectifier circuit is low. To flow in addition to the vicinity of the peak value,
The input current waveform approaches the input voltage waveform, the input power factor increases, and the power supply harmonics decrease. Further, when the charging capacitor is charged, a current flows through the charging capacitor through the series circuit of the diode and the coil in addition to the separation diode and the switching element. Therefore, a large charging current, that is, an inrush current is suppressed when the power is turned on. To be done.

In the fifth invention, the pulsating current output from the rectifying circuit is charged by the pair of coupling capacitors, and the pulsating current output from the rectifying circuit is output when one of the switching elements is turned on by the drive signal of the switch drive control circuit. The current flows through the coil, separation diode, charging capacitor and its switching element to charge the charging capacitor, and when the other switching element is turned on, high frequency is applied to the switching element, discharge lamp load circuit and coupling capacitor based on the charging voltage of the charging capacitor. Since the load current of is flowing, the input current flows to the AC voltage of the AC power supply every time a high-frequency current for charging flows to the coil, separation diode, coupling capacitor, and switching element. When the instantaneous value of the rectification circuit pulsation is low or near the peak value To flow to the outside, the input current waveform approaches the input voltage waveform, the power supply harmonic is reduced with the input power factor becomes higher.

In the sixth aspect of the invention, the pulsating current output from the rectifier circuit is charged into the charging capacitor through the separation diode, and the charging capacitor is charged when one of the switching elements is turned on by the drive signal of the switching drive control circuit. High-frequency load current flows through the switching element, fluorescent lamp, and coupling capacitor based on the voltage, and when the other switching element is turned on, high-frequency current flows through the capacitor, coil, and switching element based on the pulsating current from the rectifier circuit, and the fluorescent lamp And high-frequency load current also flows through the coupling capacitor, and the charging capacitor is charged through the isolation diode,
Each time a high-frequency current flows through the capacitor, coil, switching element, fluorescent lamp, and coupling capacitor, an input current flows with respect to the AC voltage of the AC power supply, and the input current is when the pulsating current of the rectifier circuit has a low instantaneous value or peak. Since the current flows near values other than the value, the input current waveform approaches the input voltage waveform, the input power factor increases, and the power supply harmonics decrease. 7th
In the invention described above, the switch drive control circuit according to the second to sixth inventions changes the frequency in response to the increase or decrease of the output voltage or the input current of the rectifier circuit in each half cycle period of the AC power supply, or In any one of the second to sixth inventions, by outputting at least one of a drive signal whose amplitude is varied widely so as to contradict the increase or decrease of the output voltage or the input current of the rectifier circuit in each half cycle period of the AC power supply. In the above discharge lamp lighting device, the frequency of the drive signal is high when the output voltage of the rectifier circuit is high, and the frequency of the drive signal is low when the output voltage is low, and the amplitude of the drive signal also narrows when the output voltage is high. Alternatively, the amplitude of the drive signal changes depending on the level of the output voltage of the rectifier circuit. Load current is also suppressed small, the charging capacitor and the switching element requires only one low withstand voltage,
The load current ripple is also reduced.

[0020]

【Example】

Example 1. 1 is a circuit diagram of a discharge lamp lighting device according to a first embodiment of the present invention, FIG. 2 is a circuit diagram showing a configuration of a switch drive control circuit of the device, and FIG. 3 is an operation of a switch drive control circuit of the device. FIG. 4 is a waveform diagram of voltage, current and drive signal in each part of the device. In the figure, 21 is an AC power supply, 22 is a filter for removing high frequency components, 23 is a rectifier circuit consisting of a diode bridge for full-wave rectifying the AC of the AC power supply 21, and 24 is connected to the positive output terminal of the rectifier circuit 23. It is a boosting coil. 25 is a separation diode connected in series to the coil 24, 26 is a charging capacitor connected to the rectification circuit 23 via the coil 24 and the separation diode 25, and charges the output of the rectification circuit 23, and 27 and 28 are the coil 24 and the separation diode. A pair of series-connected coupling capacitors provided between the connection point of the diode 25 and the negative side output terminal of the rectifier circuit 23.

Reference numeral 29 is a diode connected between the cathode of the separation diode 25 and the connection point of the capacitors 27 and 28, and 30 is a diode connected in parallel with the capacitor 28. 31 and 32 are a pair of serially connected switching elements connected in parallel to the charging capacitor 26, 33
Is a switch drive control circuit that controls on / off of the switching elements 31 and 32 at high frequency. The switch drive control circuit modulates the frequency according to the output voltage of the oscillation circuit 33a that oscillates a drive signal of a predetermined frequency and the rectification circuit 23. The frequency modulation circuit 33b outputs a drive signal having a corresponding pulse width. Reference numerals 34 and 35 denote flywheel diodes connected in parallel to the switching elements 31 and 32, respectively.
Reference numeral 40 denotes a discharge lamp load circuit connected between the connection points of the switching elements 31 and 32 and the connection points of the capacitors 27 and 28. The fluorescent lamp 42 is a load element connected in series with the coil 41 and the coil 40. And a condenser 43 connected in parallel with the fluorescent lamp 42. 3
Reference numerals 7 and 38 denote voltage divider resistors connected in series provided between the positive and negative output terminals of the rectifier circuit 23, and these connection points are connected to the switch drive control circuit 33 via a connection line 39.

Next, the operation of the above embodiment will be described. The pulsating current rectified from the AC power supply 21 by the rectification circuit 23 is passed through the coil 24 and the separation diode 25 to charge the charging capacitor 2
6 and is also charged with a pair of coupling capacitors 27, 28.
Is also charged. Here, when the switching element 31 is turned on by the drive signal of the switch drive control circuit 33, a high frequency load current is applied to the switching element 31, the discharge lamp load circuit 40 and the coupling capacitor 28 based on the charging voltage of the charging capacitor 26. Flowing. Further, a high-frequency load current flows through the separation diode 25, the switch element 31, and the discharge lamp load circuit 40 based on the voltage of the coupling capacitor 27. Next, when the switching element 32 is turned on by the drive signal of the switch drive control circuit 33, the coil 2 connected to the positive side output terminal of the rectifier circuit 23.
Based on the back electromotive force generated in 4, the coupling capacitor 27,
A high-frequency load current flows through the discharge lamp load circuit 40 and the switching element 32, and the charging capacitor 26 is charged via the separation diode 25. Further, a high-frequency load current flows through the discharge lamp load circuit 40 and the switch element 32 based on the voltage of the coupling capacitor 28. Such an operation is alternately repeated.

Whenever a high-frequency load current flows through the coupling capacitor 27, the discharge lamp load circuit 40, and the switching element 32 due to the counter electromotive voltage generated in the coil 24, an input current flows with respect to the AC voltage of the AC power source, Since the input current flows when the pulsating current of the rectifier circuit is low or near the peak value, the input current waveform approaches the input voltage waveform, and the effective current decreases with respect to the average current, resulting in a high input power factor. As a result, power supply harmonics decrease. Since the filter 22 is inserted between the AC power supply 21 and the rectifier circuit 23, the harmonics contained in the current output from the rectifier circuit 23 are prevented from returning to the AC power supply 21.

By the way, in the above description, the frequency of the drive signal for driving the switching elements 31 and 32 of the switch drive control circuit 33 is constant, that is, fixed. However, in this embodiment, the positive and negative outputs of the rectifying circuit 23 are output. Since the connection point of the series-connected voltage dividing resistors 37 and 38 provided between the terminals is connected to the switch drive control circuit 33 via the connection line 39, the voltage is output from the rectifier circuit 23 to the switch drive control circuit 33. The divided voltage of the pulsating flow shown in FIG. 4A by the voltage dividing resistor 38 is input. Then, the frequency of the drive signal output from the switch drive control circuit 33 varies with the predetermined frequency of the oscillation circuit 33a and the frequency modulation circuit 33b changes according to the level of the divided voltage as shown in FIG. 4B. (See FIG. 3)
As shown in (d) and (e), the amplitude of the drive signal is narrow when the divided voltage is high so as to contradict the high and low of the divided voltage,
Widen when the divided voltage is low. Therefore, the step-up ratio to the charging capacitor 26 is reduced and the load current is also suppressed to be small, the charging capacitor 26 and the switching elements 31, 32 need only have a low breakdown voltage, and the ripple of the load current is reduced. 4F shows the waveform of the input current output from the rectifier circuit 23.

In this embodiment, the switch drive control circuit 3
Although the divided voltage of the pulsating flow output voltage output from the rectifier circuit 23 is input to the circuit 3, the frequency of the drive signal of the switch drive control circuit 33 is changed according to the level of the divided voltage. The switch drive control circuit 35 includes a rectifier circuit 23.
Even if the input current output from is input, the same effect is produced.

FIG. 5 is a circuit diagram showing the configuration of another switch drive control circuit, FIG. 6 is a graph for explaining the operation of the switch drive control circuit, and FIG. 7 is a discharge lamp lighting having the switch drive control circuit. It is a waveform diagram of the voltage and the drive signal in each part of the device. In the switch drive control circuit 133 shown in FIG. 5, the oscillation circuit 133a outputs a drive signal of a predetermined frequency, whereas in the pulse width modulation circuit 133b, as shown in FIG. 7, the divided voltage of the output voltage of the rectification circuit 23 is obtained. The pulse width of the drive signal is narrowed when the divided voltage is high and widened when the divided voltage is low so as to contradict the high and low (see FIG. 6). Therefore, the boosting ratio to the charging capacitor 26 is reduced and the load current is also suppressed to be small, and the charging capacitor 26 and the switching elements 31, 3 are
No. 2 has a low breakdown voltage, and the ripple of the load current is small.

FIG. 8 is a circuit diagram showing the configuration of another switch drive control circuit, and FIG. 9 is a waveform diagram of drive signals of the switch drive control circuit. In the switch drive control circuit 233 shown in FIG. 8, the oscillation circuit 63a outputs a drive signal of a predetermined frequency, while in the frequency modulation circuit 233b, the output voltage of the rectifier circuit 23 is changed according to the level of the divided voltage. With respect to the drive signal from the frequency modulation circuit 233b, the pulse width modulation circuit 233c narrows the pulse width of the drive signal when the divided voltage is high so as to contradict the level of the divided voltage of the output voltage of the rectifier circuit 23, Widely output when the divided voltage is low. Therefore, the switch drive control circuit 23
3 outputs the drive signal whose frequency and pulse width are simultaneously changed according to the level of the divided voltage of the output voltage of the rectifier circuit 23, so that the step-up ratio to the charging capacitor 26 is further reduced and the load current is also reduced. The charging capacitor 26 and the switching elements 31 and 32 can be kept small, and the withstand voltage can be low, and the ripple of the load current can be reduced.

Example 2. FIG. 10 is a circuit diagram of a discharge lamp lighting device according to a second embodiment of the present invention. In this embodiment, a rectifier circuit 23 for full-wave rectifying the AC of the AC power supply 21 via a filter 22 and a coil 2 for boosting the output of the rectifier circuit 23.
4, a charging capacitor 26 for charging via the isolation diode 25, a pair of serially connected switching elements 31, 32 connected in parallel to the charging capacitor 26, and high-frequency drive signals are output to the switching elements 31, 32, respectively. A fixed frequency type switch drive control circuit 333,
Flywheel diodes 34 and 35 connected in parallel to the switching elements 31 and 32, a pair of series-connected coupling capacitors 46 and 47 connected in parallel to the charging capacitor 26, and a pair of switching elements 31 and 3
2 and the discharge lighting load circuit 40 provided between the connection point of the pair of coupling capacitors 46 and 47, and the coil 2
4 is provided with a voltage supply line 48 that connects the connection point of the separation diode 25 and the connection point of the pair of switching elements 31 and 32.

In this embodiment, the pulsating current output from the rectifying circuit 23 is charged in the charging capacitor 26 via the coil 24 and the separation diode 25. The pair of coupling capacitors 46 and 47 are also charged. Then, when one switching element 31 is turned on by the drive signal of the switch drive control circuit 333, a high-frequency load current flows through the discharge lamp load circuit 40 and the coupling capacitor 47 based on the charging voltage of the charging capacitor 26. At this time, the switching element 31 is also based on the voltage of the coupling capacitor 46.
A load current flows through the discharge lamp load circuit 40 via the load current. next,
When the other switching element 32 is turned on, based on the counter electromotive voltage generated in the coil 24 connected to the positive side output terminal of the rectifying circuit 23, the current is not supplied to the discharge lamp load circuit 40, and its switching is performed via the voltage supply line 48. A high-frequency current flows through the element 32, and the charging capacitor 26 is also charged via the separation diode 25. At this time, the load current also flows through the discharge lamp load circuit 40 via the switching element 32 based on the voltage of the coupling capacitor 47. Thus, the input current flows with respect to the AC voltage of the AC power supply 21 each time a high-frequency current flows through the switching element 32 via the voltage supply line due to the back electromotive force generated in the coil 24.
Since the input current flows when the instantaneous value of the pulsating current of the rectifier circuit 23 is low or other than near the peak value, the input current waveform approaches the input voltage waveform, the input power factor increases, and the power supply harmonics decrease. It is possible to operate without the coupling capacitor 46.

Example 3. FIG. 11 is a circuit diagram of a discharge lamp lighting device according to a third embodiment of the present invention. In this embodiment, a rectifier circuit 23 for full-wave rectifying the AC power supply voltage of the AC power supply 21 through a filter 22, a partial smoothing circuit 50 for partially charging the output of the rectifier circuit 23 through a coil 49, and a partial smoothing circuit. A pair of series-connected switching elements 31 and 32 connected in parallel to the circuit 50, a fixed frequency switch drive control circuit 333 which outputs a high-frequency drive signal to each of the pair of switching elements, and the switching elements 31 and 32.
Discharge lighting load circuit 40 in which one terminal is connected to a connection point of a pair of switching elements 31 and 32 and flywheel diodes 34 and 35 connected in parallel to 32, respectively.
And a coupling capacitor 46 connected between the other terminal of the discharge lighting load circuit 40 and the high potential side of the switching element 31. The partial smoothing circuit 5
0 is capacitors 50a, 50b and diodes 50c, 5
0d and 50e.

In this embodiment, the rectification circuit 23 rectifies the AC power supply voltage of the AC power supply 21, and the pulsating current output from the rectification circuit 23 is partially charged by the partial smoothing circuit 50 via the coil 49 to drive the switch. When one of the switching elements 32 is turned on by the drive signal of the control circuit 333, a high-frequency load current flows to the discharge lamp load circuit 40 via the coupling capacitor 46 based on the charging voltage of the partial smoothing circuit 50, causing a pulsating current of the coil 49. Even when the voltage is higher than the charging voltage of the partial smoothing circuit 50, based on the voltage of the coil 49,
When a high-frequency load current flows through the discharge lamp load circuit 40 and the other switching element 31 is turned on, the discharge lamp load circuit 40 is based on the voltage charged in the coupling capacitor 46.
High frequency current is allowed to flow through. As described above, even when the pulsating voltage of the coil 49 is higher than the charging voltage of the partial smoothing circuit 50, the AC voltage of the AC power source is changed every time a high-frequency load current flows in the discharge lamp load circuit 50 based on the voltage of the coil 49. On the other hand, since the input current flows, and the input current also flows when the instantaneous value of the pulsating current of the rectifier circuit 23 is low or near the peak value, the input current waveform approaches the input voltage waveform, and the input power factor increases. Power supply harmonics are reduced. Further, since the voltage charged in the partial smoothing circuit 50 is half of the voltage output from the rectifying circuit 23, the breakdown voltage of the switching elements 31, 32 can be low.

Example 4. FIG. 12 is a circuit diagram of a discharge lamp lighting device according to a fourth embodiment of the present invention. In this embodiment, a rectifier circuit 23 for full-wave rectifying the AC of the AC power source 21 via a filter 22, and a pair of series-connected coupling capacitors 27 connected in parallel between the positive and negative output terminals of the rectifier circuit 23.
28, a pair of switching elements 31 and 32 connected in series to the positive and negative output terminals of the rectifying circuit 23 via the isolation diode 25, and a pair of switching elements 3.
Fixed-frequency switch drive control circuit 333 that outputs high-frequency drive signals to 1 and 32, flywheel diodes 34 and 35 that are respectively connected in parallel to switching elements 31 and 32, and a pair of switching elements 3
The discharge lighting load circuit 40 provided between the connection point of the terminals 1, 32 and the connection point of the pair of coupling capacitors 27, 28 and the connection point of the pair of switching elements 31, 32 are connected via a diode 51. The coil 52, the charging capacitor 54 connected between the coil 52 and the low potential side of the switching element 32, the coil 52 and the switching element 31.
And a bypass capacitor 55 connected in parallel to the pair of switching elements 31 and 32.

In this embodiment, the pulsating current output from the rectifying circuit 23 is charged by the pair of coupling capacitors 27 and 28,
When one of the switching elements 31 is turned on by the drive signal of the switching drive control circuit 333, the pulsating current output from the rectifier circuit 23 passes through the separation diode 25, the switching element 31, the series circuit of the diode 51 and the coil 52, and the charging capacitor 54. In addition to being charged, the coupling capacitor 28 is charged via the switching element 31 and the discharge lighting load circuit 40. Next, when the other switching element 32 is turned on, a high-frequency load current flows through the switching lamp 32 to the discharge lamp load circuit 40 based on the voltage of the coupling capacitor 28. In this way, based on the pulsating voltage of the rectifier circuit 23, the switching element 31, the discharge lighting load circuit 40, and the coupling capacitor 2
The input current flows with respect to the AC voltage of the AC power supply every time a high-frequency current flows in 8, and the input current flows when the instantaneous value of the pulsating current of the rectifier circuit 23 is low or other than near the peak value. Since the waveform approaches the input voltage waveform, the input power factor increases and the power supply harmonics decrease. Also, when the charging capacitor 54 is charged, the charging capacitor 5
4, a current flows through the series circuit of the diode 51 and the coil 52 in addition to the separation diode 25 and the switching element 31, so that a large charging current, that is, a rush current, is suppressed when the power is turned on.

Example 5. FIG. 13 is a circuit diagram of a discharge lamp lighting device according to a fifth embodiment of the present invention. In this embodiment, a rectifier circuit 23 for full-wave rectifying the alternating current of an AC power source 21 via a filter 22 and a pair of series-connected parallel-connected positive and negative output terminals of the rectifier circuit 23 via a boosting coil 24. Coupling capacitors 27, 28 and a pair of coupling capacitors 2
A pair of series-connected switching elements 31, 32 connected in parallel to 7, 28 via a separation diode 25;
A fixed frequency switch drive control circuit 333 that outputs a high-frequency drive signal to the pair of switching elements 31 and 32; and flywheel diodes 34 and 35 that are connected in parallel to the switching elements 31 and 32, respectively.
The discharge lighting load circuit 40 provided between the connection point of the pair of switching elements 31 and 32 and the connection point of the pair of coupling capacitors 27 and 28, and the pair of switching elements 31 and
A diode 51 connected to the connection point of 32, a charging capacitor 54 connected between the diode 51 and the high potential side of the switching element 31, and a coil 51 connected between the coil 51 and the low potential side of the switching element 32. Diode 5
3, a bypass capacitor 55 connected in parallel to the pair of switching elements 31 and 32, and a diode 56 provided between the positive side output terminal of the rectifier circuit 23 and the connection point of the pair of switching elements 31 and 32. It will be.

In this embodiment, the pulsating current output from the rectifying circuit 23 is coupled via the coil 24 to the coupling capacitors 27 and 28.
When one of the switching elements 32 is turned on by the drive signal of the switching drive control circuit 333, the pulsating current coil 24, the separation diode 25, the charging capacitor 54, the diode 5 output from the rectifying circuit 23 are charged.
1. Flow with the switching element 32 and charge capacitor 54
Is charged, and next, when the other switching element 31 is turned on, based on the charging voltage of the charging capacitor 54,
A high-frequency load current flows through the discharge lamp load circuit 40 and the coupling capacitor 28 via the switching element 31, and the separation diode 2 is generated based on the voltage of the coupling capacitor 27.
5, the discharge lamp load circuit 40 via the switching element 31
Current flows through. In this way, the coil 24, the separation diode 25, the charging capacitor 54, the switching element 32
Whenever a high-frequency current for charging the charging capacitor 54 flows, an input current flows with respect to the AC voltage of the AC power source,
Since the input current flows even when the instantaneous value of the pulsating current of the rectifier circuit is low or other than near the peak value, the input current waveform approaches the input voltage waveform, the input power factor increases, and the power supply harmonics decrease. The diode 56 is for charging the coupling capacitor 27 based on the charging voltage of the charging capacitor 54 when the switching element 31 is turned on.

Example 6. FIG. 14 is a circuit diagram of a discharge lamp lighting device according to a sixth embodiment of the present invention, and FIG. 15 is a waveform diagram of voltage and current in each part of the device. In this embodiment, a rectifier circuit 23 for full-wave rectifying the AC of the AC power supply 21 via a filter 22 and an output of the rectifier circuit 23 for separating the diode 2
5, a pair of switching elements 31 and 32 connected in parallel to the charging capacitor 26, which is connected in parallel to the charging capacitor 26, and a pair of switching elements 3.
Fixed-frequency switch drive control circuit 333 that outputs high-frequency drive signals to 1 and 32, flywheel diodes 34 and 35 that are respectively connected in parallel to switching elements 31 and 32, and a pair of switching elements 3
Coil 41 connected to the connection point of 1, 32 and coil 4
1 and the low potential side of the switching element 32, the discharge lamp 42 in which the capacitor 46 is connected in series, between the connection point of the coil 41 and the discharge lamp 42 and the positive side output terminal of the rectifier circuit 23. And a connected capacitor 57. A discharge lighting load circuit 40 is configured by the coil 41, the discharge lamp 42, and the capacitor 43 connected in parallel to the discharge lamp 42.

In this embodiment, the alternating current of the alternating current power source 21 is shown in FIG.
The power supply voltage shown in (a) of 5 is rectified by the rectifier circuit 23,
The pulsating current shown in FIG. 15B output from the rectifying circuit 23 is charged in the charging capacitor 26 via the separation diode 25. Then, the switching drive control circuit 33
When one of the switching elements 31 is turned on by the drive signal of No. 3, the switching element 31, the coil 41, the fluorescent lamp 42, and the coupling capacitor 46 (see FIG. 15) based on the charging voltage of the charging capacitor 26 shown in FIG. The high frequency load current shown in c) flows. Next, when the other switching element 32 is turned on, the rectifier circuit 23
A high-frequency current flows through the capacitor 57, the coil 41, and the switching element 32 based on the pulsating current from the rectifying circuit 23, and a high-frequency current also flows through the fluorescent lamp 42 and the coupling capacitor 46. The charging capacitor 26 is charged via 25. Thus, when the switching element 32 is turned on, the capacitor 57 and the coil 4 are generated based on the pulsating current from the rectifier circuit 23.
Whenever a high-frequency current flows through the switching element 32 and the switching element 32, a high-frequency current also flows through the fluorescent lamp 42 and the coupling capacitor 46, an input current flows with respect to the AC voltage of the AC power supply 21. When the instantaneous value of the pulsating current is low or flows other than near the peak value, the input current waveform approaches the input voltage waveform as shown in FIG. 15 (e), the input power factor increases and the power supply harmonics decrease. Become. When a high frequency current flows through the capacitor 57, the coil 41 and the switching element 32, the capacitor 5
7, the high-frequency current flows even when the pulsating voltage from the rectifier circuit 23 is lower than the voltage of the charging capacitor 26, and the input current waveform is closer to the input voltage waveform, so that the input power factor is higher. Become.

The switch drive control circuit 333 of the second embodiment shown in FIG. 10 to the sixth embodiment shown in FIG. 14 outputs a drive signal of a fixed frequency.
By using the switch drive control circuit 33 shown in FIG. 2, the switch drive control circuit 133 shown in FIG. 5, or the switch drive control circuit 233 shown in FIG. It goes without saying that the ratio is reduced as a result, the load current is also suppressed to a small value, the charging capacitor and the switching element need only have a low withstand voltage, and the ripple of the load current is reduced. Note that FIG. 16 shows waveforms of voltages, currents, and drive signals at respective parts when frequency control is performed using the switch drive control circuit 33 shown in FIG. 2 with respect to the third embodiment shown in FIG. Show. In this case, the frequency of the drive signal output from the switch drive control circuit 33 changes according to the fluctuation of the power supply voltage as shown in (c) of FIG. 16, and the input current has the waveform shown in (d) of FIG. Flowing in.

[0039]

According to the first aspect of the present invention, the pulsating current output from the rectifying circuit is charged into the charging capacitor through the coil and the separating diode, and when one of the switching elements is turned on, the discharge lamp is based on the charging voltage of the charging capacitor. When a high-frequency load current flows in the load circuit and the coupling capacitor and the other switching element is turned on, the coupling capacitor, the discharge lamp load circuit, and the coupling capacitor, the discharge lamp load circuit, based on the counter electromotive voltage generated in the coil connected to the positive output terminal of the rectifier circuit. Since a high frequency current flows through the switching element and the charging capacitor is charged through the separation diode, a high frequency current flows through the coupling capacitor, the discharge lamp load circuit, and the switching element due to the back electromotive force generated in the coil. The input current flows for each AC voltage of the AC power supply, and the input current is rectified. Since the flow in addition to the vicinity or when the peak value instantaneous value is low pulsating approaches the input current waveform is the input voltage waveform has the effect that the power supply harmonic is reduced with the input power factor becomes higher. Further, the switch drive control circuit changes the frequency within each half cycle period of the AC power supply in response to the increase or decrease of the output voltage or the input current of the rectifier circuit, or the amplitude within each half cycle period of the AC power supply. Since the output voltage of the rectifier circuit or at least one of the drive signals that are varied widely so as to conflict with the increase or decrease of the input current is output, the frequency of the drive signal is high when the output voltage of the rectifier circuit is high, and it is low when the output voltage is low. Since the frequency of the drive signal becomes lower and the amplitude of the drive signal becomes smaller accordingly when the output voltage is high, or the amplitude of the drive signal changes according to the level of the output voltage of the rectifier circuit, the voltage boosted to the charging capacitor As a result, the load current is kept small and the charging capacitor and switching element have low withstand voltage. It has the effect that also small ripple flow.

According to a second aspect of the invention, the pulsating current output from the rectifying circuit is charged into the charging capacitor through the coil and the separation diode, and when one switching element is turned on, the switching element is switched based on the charging voltage of the charging capacitor. When a high-frequency load current flows through the discharge lamp load circuit and the coupling capacitor and the other switching element is turned on, it is applied to the discharge lamp load circuit based on the counter electromotive voltage generated in the coil connected to the positive output terminal of the rectifier circuit. Instead, a high-frequency current is made to flow to the switching element via the voltage supply line.Therefore, every time a high-frequency current flows to the switching element due to the counter electromotive voltage generated in the coil, input is made to the AC voltage of the AC power supply. A current flows, and the input current flows not only when the instantaneous value of the rectification circuit pulsation is low or near the peak value. Because, approaches the input current waveform is the input voltage waveform has the effect that the power supply harmonic is reduced with the input power factor becomes higher.

In the third aspect of the invention, the pulsating current output from the rectifying circuit is charged by the partial smoothing circuit via the coil, and when one of the switching elements is turned on, the coupling capacitor and the discharge lamp are discharged based on the charging voltage of the partial smoothing circuit. A high-frequency load current flows in the load circuit, and when the other switching element is turned on, a high-frequency current flows in the discharge lamp load circuit based on the voltage charged in the capacitor connected to that switching element. , Each time a high-frequency load current flows in the discharge lamp load circuit due to the voltage charged in the partial smoothing circuit, an input current flows with respect to the AC voltage of the AC power supply, and the input current has a low pulsating current instantaneous value in the rectifier circuit. Since the current flows near the peak value or near the peak value, the input current waveform approaches the input voltage waveform, increasing the input power factor and reducing power supply harmonics. Since the voltage charged to the partial smoothing circuit is 1/2 of the voltage output from the rectifier circuit, it has the effect that requires only a withstand voltage of the switching element is low.

According to a fourth aspect of the present invention, the pulsating current output from the rectifying circuit is charged by a pair of coupling capacitors, and when one switching element is turned on, the pulsating current output from the rectifying circuit is separated diode, its switching element, When the charging capacitor is charged through the series circuit of the diode and the coil, the discharge lamp load circuit, the high-frequency load current flows through the coupling capacitor, and when the other switching element is turned on, the discharge lamp load circuit is based on the voltage of the coupling capacitor,
Since a high-frequency load current flows through the switching element, an input current flows for the AC voltage of the AC power supply every time a high-frequency load current flows through the switching element, the discharge lamp load circuit, and the coupling capacitor. Occurs when the instantaneous value of the pulsating current of the rectifier circuit is low or other than near the peak value, the input current waveform approaches the input voltage waveform, the input power factor increases, and the power supply harmonics decrease. Further, when the charging capacitor is charged, a current flows through the charging capacitor through the series circuit of the diode and the coil in addition to the separation diode and the switching element. Therefore, a large charging current, that is, an inrush current is suppressed when the power is turned on. Has the effect of being

In a fifth aspect of the invention, the pulsating current output from the rectifier circuit is charged by a pair of coupling capacitors via a coil,
When one switching element is turned on, the pulsating current output from the rectifier circuit flows to the coil, separation diode, charging capacitor and its switching element to charge the charging capacitor, and when the other switching element is turned on, the charging voltage of the charging capacitor. High-frequency load current is allowed to flow through the switching element, discharge lamp load circuit and coupling capacitor based on the above, so every time a high-frequency current for charging flows through the coil, separation diode, coupling capacitor and switching element, an AC The input current flows with respect to the AC voltage of the power supply, and the input current also flows when the pulsating current of the rectifier circuit is low or near the peak value, so the input current waveform approaches the input voltage waveform, and the input power factor Has the effect of increasing the power supply and reducing the power supply harmonics.

According to a sixth aspect of the invention, the pulsating current output from the rectifying circuit is charged into the charging capacitor through the separation diode, and when one switching element is turned on, the switching element, the discharge lamp, and the switching element are discharged based on the charging voltage of the charging capacitor. When a high-frequency load current flows through the coupling capacitor and the other switching element is turned on, a high-frequency current flows through the capacitor, coil, and switching element based on the pulsating current from the rectifier circuit, and a high-frequency load current also flows through the discharge lamp and coupling capacitor. Since the charging capacitor is charged via the separation diode, the charging voltage is input to the AC voltage of the AC power supply each time a high frequency current flows through the capacitor, coil, switching element, discharge lamp and coupling capacitor. A current flows, and the input current is the instantaneous pulsating current of the rectifier circuit. Since the flow in addition or when the peak value near lower, closer to the input current waveform is the input voltage waveform has the effect that the power supply harmonic is reduced with the input power factor becomes higher.

In the seventh invention, the switch drive control circuit in the second to sixth inventions changes the frequency within each half cycle period of the AC power supply in accordance with the increase or decrease of the output voltage or the input current of the rectifier circuit. By outputting at least one of the drive signal whose amplitude is changed so as to conflict with the increase or decrease of the output voltage or the input current of the rectifier circuit in each half cycle period of the AC power supply. In any of the discharge lamp lighting devices according to the second to sixth inventions, the frequency of the drive signal is high when the output voltage of the rectifier circuit is high, and the frequency of the drive signal is low when the output voltage is low, and the amplitude of the drive signal is accordingly increased. It decreases when the output voltage is high, or the magnitude of the drive signal amplitude changes according to the level of the output voltage of the rectifier circuit. Ratio resulting in the load current is also suppressed small with small, charging capacitor and the switching element requires only one low withstand voltage has the effect that the ripple of the load current is also reduced.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a discharge lamp lighting device according to a first embodiment of the present invention.

FIG. 2 is a circuit diagram showing a configuration of a switch drive control circuit of the device.

FIG. 3 is a graph for explaining the operation of the switch drive control circuit of the device.

FIG. 4 is a waveform diagram of voltage, current and drive signal in each part of the device.

FIG. 5 is a circuit diagram showing a configuration of another switch drive control circuit.

FIG. 6 is a graph for explaining the operation of the switch drive control circuit.

FIG. 7 is a waveform diagram of a voltage and a drive signal in each part of the discharge lamp lighting device having the switch drive control circuit.

FIG. 8 is a circuit diagram showing a configuration of another switch drive control circuit.

FIG. 9 is a waveform diagram of the switch drive control circuit.

FIG. 10 is a circuit diagram of a discharge lamp lighting device according to a second embodiment of the present invention.

FIG. 11 is a circuit diagram of a discharge lamp lighting device according to a third embodiment of the present invention.

FIG. 12 is a circuit diagram of a discharge lamp lighting device according to a fourth embodiment of the present invention.

FIG. 13 is a circuit diagram of a discharge lamp lighting device according to a fifth embodiment of the present invention.

FIG. 14 is a circuit diagram of a discharge lamp lighting device according to a sixth embodiment of the present invention.

FIG. 15 is a waveform diagram of voltage and current in each part of the device.

16 is a waveform diagram of voltage, current, and drive signal at each part when frequency control is performed in the same device of FIG. 11.

FIG. 17 is a circuit diagram of a conventional discharge lamp lighting device.

FIG. 18 is an input voltage and input current waveform diagram in a circuit of a conventional discharge lamp lighting device.

[Explanation of symbols]

 21 AC power source 23 Rectifier circuit 24 Coil 25 Separation diode 26 Charging capacitor 27 Coupling capacitor 28 Coupling capacitor 29 Diode 30 Diode 31 Switching element 32 Switching element 33 Switch drive control circuit 40 Discharge lamp load circuit

Claims (7)

[Claims] 1. A rectifying circuit for full-wave rectifying the alternating current of an alternating current power source, a charging capacitor for charging the output of the rectifying circuit via a coil and a separation diode, and a pair of serially connected parallel connection to the charging capacitor. A switching element,
A switch drive control circuit that outputs a high-frequency drive signal to each of the pair of switching elements, and a pair of series-connected couplings provided between the connection point of the coil and the separation diode and the negative side output terminal of the rectifier circuit. A capacitor,
A discharge lighting load circuit provided between a connection point of the pair of switching elements and a connection point of the pair of coupling capacitors, and one of the pair of coupling capacitors connected in parallel via a separation diode, One of them is provided with a pair of series-connected diodes that are directly connected in parallel, and the switch drive control circuit adjusts the frequency according to the increase or decrease of the output voltage or the input current of the rectifier circuit within each half cycle period of the AC power supply. It is characterized in that it outputs at least one of a changed drive signal or a drive signal whose amplitude is changed so as to be contradictory to increase or decrease of the output voltage or the input current of the rectifier circuit in each half cycle period of the AC power supply. Discharge lamp lighting device. 2. A rectifying circuit for full-wave rectifying the alternating current of an alternating current power source, a charging capacitor for charging the output of the rectifying circuit via a coil and a separation diode, and a pair of serially connected parallel connection to the charging capacitor. A switching element,
A switch drive control circuit that outputs a high-frequency drive signal to each of the pair of switching elements, a pair of series-connected coupling capacitors that are connected in parallel to the charging capacitor, a connection point of the pair of switching elements, and the pair of switching elements. A discharge lighting load circuit provided between the connection point of the coupling capacitor and a voltage supply line connecting the connection point of the coil and the separation diode and the connection point of the pair of switching elements. Discharge lamp lighting device. 3. A rectifier circuit for full-wave rectifying the alternating current of an AC power supply, a partial smoothing circuit for charging the output of the rectifier circuit via a coil, and a pair of series-connected switchings connected in parallel to the partial smoothing circuit. An element, a switch drive control circuit that outputs a high-frequency drive signal to each of the pair of switching elements, a discharge lighting load circuit in which one terminal is connected to a connection point of the pair of switching elements, and the discharge lighting load circuit And a coupling capacitor connected between the other terminal of the switching element and the high potential side of the switching element. 4. A rectifier circuit for full-wave rectifying the alternating current of an AC power supply, a pair of series-connected coupling capacitors connected in parallel to the positive and negative output terminals of the rectifier circuit, and a separation diode for the positive and negative output terminals of the rectifier circuit. A pair of serially connected switching elements connected in parallel, a switch drive control circuit that outputs a high-frequency drive signal to each of the pair of switching elements, a connection point of the pair of switching elements, and a pair of coupling capacitors. A discharge lighting load circuit provided between the connection point, a coil connected to the connection point of the pair of switching elements via a diode, and a coil connected between the coil and the low potential side of the switching element. A charging capacitor, and a diode connected between the coil and the high potential side of the switching element. Discharge lamp lighting device. 5. A rectifying circuit for full-wave rectifying the alternating current of an AC power source, a pair of series-connected coupling capacitors connected in parallel to the positive and negative output terminals of the rectifying circuit via a coil, and a pair of the coupling capacitors. A pair of serially connected switching elements connected in parallel via a diode, a switch drive control circuit that outputs a high-frequency drive signal to each of the pair of switching elements, a connection point of the pair of switching elements, and the pair of switching elements. A discharge lighting load circuit provided between the connection point of the coupling capacitor, a diode connected to the connection point of the pair of switching elements, and a diode connected between the diode and the high potential side of the switching element. A charging capacitor, a diode connected between the coil and the low potential side of the switching element, and the rectifier circuit A discharge lamp lighting device comprising a diode connected between a positive output terminal and a connection point of the pair of switching elements. 6. A rectifying circuit for full-wave rectifying the alternating current of an AC power source, a charging capacitor for charging the output of the rectifying circuit via a separating diode, and a pair of series-connected switching elements connected in parallel to the charging capacitor. A switch drive control circuit that outputs a high-frequency drive signal to each of the pair of switching elements, a coil connected to a connection point of the pair of switching elements, and between the coil and the low potential side of the switching element. A discharge lighting load circuit in which the provided capacitor is connected in series, and a capacitor connected between a connection point of the coil and the discharge lighting load circuit and the positive side output terminal of the rectifier circuit. Discharge lamp lighting device. 7. The switch drive control circuit comprises a drive signal whose frequency is changed in response to an increase / decrease in an output voltage or an input current of the rectifier circuit within each half cycle period of the AC power supply, or an amplitude of each half of the AC power supply. 7. The discharge signal according to claim 2, 3, 4, 5 or 6, wherein at least one of a drive signal changed in a wide and narrow manner so as to contradict an increase or decrease in the output voltage or the input current of the rectification circuit within the cycle period. Electric lighting device.