JPH06315272A - Inverter apparatus - Google Patents

Abstract

PURPOSE:To enable an increase of an input power factor and a reduction of higher harmonics in a power source. CONSTITUTION:The pulsating current from a rectifier circuit 23 is charged into a charge capacitor 26 through a coil 24 and isolation diode 25. When one pair of switching elements 28 and 29 are turned on by the drive signal from a switch drive control circuit 35, a high frequency load current flows due to the charging voltage of the charge capacitor 26 through the switching element 29, discharge lamp load circuit 36, coupling capacitor 40, and switching element 28. When the other pair of switching elements 27, 30 are turned on, a high frequency current flows through the switching element 27, coupling capacitor 40, discharge lamp load circuit 36, and switching element 30 due to a counterelectromotive force generated in the coil 24 connected to the positive output terminal of the rectifying circuit, and the charge capacitor 26 is charged through the isolation diode 24.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to, for example, an inverter device for lighting a discharge lamp, and more particularly to an inverter 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. 24 is a circuit diagram of a conventional inverter device, and FIG. 25 is a waveform diagram of an input voltage and an input current of the inverter 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 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. Diodes 6 and 7 are equivalently connected in antiparallel to the switching elements 4 and 5 for the purpose of flowing a regenerative current. 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 inverter 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 inverter device is of the capacitor input type as described above, and since the power supply input current has a pulse-like sharp shape as shown in FIG. 26, the input power factor is small. However, there is a problem in that the power supply harmonics and the power supply 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. The purpose is to obtain an inverter device.

[0006]

According to a first aspect of the present invention, a rectifier circuit for full-wave rectifying an alternating current of an alternating current power source, a charging capacitor connected to positive and negative output terminals of the rectifier circuit via a coil and a separating diode, One end side is connected to both ends of the separation diode respectively, and the other end side is connected to the negative side output terminal of the rectifier circuit, respectively. A switch drive control circuit that outputs a high-frequency drive signal to the above, and a discharge lamp load circuit that is connected via a capacitor between the connection points of the pair of switching elements.

According to a second aspect of the present invention, a pair of voltage dividing resistors connected in series are connected in parallel to the charging capacitor, and a high potential side of a pair of switching elements connected to the cathode of the separation diode and the pair of voltage dividing resistors. The connection point of the piezoresistor is connected by a coupling diode.

According to a third aspect of the present invention, a rectifying circuit for full-wave rectifying the alternating current of an alternating current power source, a separating diode connected to the positive side output terminal of the rectifying circuit, and one end of each of the separating diodes are connected to one end side of the rectifying circuit. The other side of the circuit is connected to the negative output terminal of the circuit, and two pairs of each pair forming a bridge are connected in series, and a pair of switching elements connected to the cathode of the separation diode are connected in parallel. A series-connected diode and a charging capacitor whose cathode is located on the high potential side of the switching element, a switch drive control circuit for outputting a high-frequency drive signal to the two sets of switching elements, and the pair of switching elements Connected to the discharge lamp load circuit connected via a capacitor between the connection points and the cathode of the isolation diode. It is made and a series connection of a diode and a coil provided between the connection point and the connection point between the diode and the charging capacitor of the series connection of a pair of switching elements.

According to a fourth aspect of the present invention, a rectifying circuit for full-wave rectifying the alternating current of an alternating current power source, a separating diode connected to a positive side output terminal of the rectifying circuit via a coil, and one end side at each end of the separating diode. A switching element connected to each other and connected in series with two pairs of each pair forming a bridge by connecting the other end side to the negative output terminal of the rectifier circuit, and a pair of switching elements connected to the cathode of the separation diode. A diode and a charging capacitor connected in series, the cathode of which is connected to the low potential side of the switching element, and a switch drive control circuit which outputs a high frequency drive signal to the two sets of switching elements, The discharge lamp load circuit connected via a capacitor between the connection points of each pair of switching elements and the separation diode It is made and a diode provided between the connection point and the connection point between the diode and the charging capacitor of the series connection of a pair of switching elements connected to the over-de.

According to a fifth aspect of the invention, a diode for clipping a peak voltage generated on the output side of the rectifier circuit to an applied voltage value of the charging capacitor is connected in parallel to a series circuit composed of the coil and the separation diode. It was done.

According to a sixth aspect of the present invention, a capacitor is connected between the positive and negative output terminals of the rectifier circuit, the capacitor having a capacitance set so as to resonate with the coil at a frequency higher than the circuit operating frequency.

According to a seventh aspect of the invention, a partial smoothing circuit is provided in place of the above charging capacitor.

In an eighth aspect of the present invention, the discharge lamp load circuit is connected to a transformer and a secondary side coil of the transformer in which a primary side coil is connected via a capacitor between connection points of the switching elements of each set. , A discharge lamp in which a capacitor is connected in parallel.

According to a ninth aspect of the present invention, a rectifying circuit for full-wave rectifying the alternating current of an alternating current power source, a charging capacitor connected to the positive and negative output terminals of the rectifying circuit via a separating diode, and one end side of each of the separating diode ends. A switching element in which each pair of two pairs, which are connected to each other and form the bridge, are connected in series to the negative side output terminal of the rectifier circuit, and a high-frequency drive signal is supplied to the two switching elements. A switch drive control circuit for outputting, a discharge lamp load circuit connected via a capacitor between connection points of the pair of switching elements, and a power supply input terminal of any one of the AC power supply and the rectifier circuit. Or a coil connected between the negative side output terminal of the rectifier circuit and the ground side.

In a tenth aspect of the present invention, the switch drive control circuit according to the first to ninth aspects of the present invention changes the frequency within each half cycle period of the AC power source in accordance with increase or decrease of the output voltage or the input current of the rectifier circuit. 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.

[0016]

According to the first aspect of the invention, the pulsating current output from the rectifying circuit is charged into the charging capacitor through the coil and the separating diode, and the driving signal of the switch driving control circuit causes one of the opposing switching elements of each group to be turned on. When each is turned on, a high-frequency load current flows with the switching element, the discharge lamp load circuit, the coupling capacitor and the switching element based on the charging voltage of the charging capacitor, and the positive side of the rectifier circuit when the opposite switching element of each of the other pairs is turned on. Based on the counter electromotive voltage generated in the coil connected to the output terminal, the switching element, coupling capacitor, discharge lamp load circuit, switching element and high frequency load current flow, and the charging capacitor is charged via the separation diode. Therefore, the back electromotive force generated in the coil causes the switch to switch. Each time a high-frequency load current flows through the switching element, coupling capacitor, discharge lamp load circuit, and switching element, an input current flows with respect to the AC voltage of the AC power supply, and that input current is when the instantaneous value of the pulsating current in the rectifier circuit is low. Alternatively, the input current flows to other than near the peak value, and the input current of each pair of opposing switching elements on one side and the opposing switching element of each pair on the other side are turned on / off by the drive signal of the switch drive control circuit. Since they are the same, they flow in the same phase as the power supply voltage, so that the input current waveform approaches the input voltage waveform, the input power factor increases, and the power supply harmonics decrease.

In the second invention, a pair of voltage dividing resistors connected in series are connected in parallel to the charging capacitor, and the high potential side of a pair of switching elements connected to the cathode of the separation diode and the pair of switching elements. Since a connection diode is used to connect to the connection point of the voltage dividing resistor, a high frequency load is applied to the switching element, the discharge lamp load circuit, the coupling capacitor and the switching element when the opposing switching elements of each one of the above groups are turned on. Since the charging voltage of the charging capacitor for passing the current is the voltage divided by the voltage dividing resistor, the withstand voltage of the switching element can be low.

According to the third aspect of the invention, when the switching signals of one of the sets are turned on by the drive signal of the switch drive control circuit, the switching element, the coupling capacitor, and the discharge capacitor are discharged based on the pulsating current output from the rectifier circuit. A high-frequency load current flows through the electric lamp load circuit, the switching element, and further, a pulsating current flows from the discharge lamp load circuit to the charging capacitor through the diode and the coil, and the charging capacitor is charged. When turned on, a diode, a switching element, a discharge lamp load circuit, a coupling capacitor and a switching element, and a high-frequency load current flow based on the charging voltage of the charging capacitor, so based on the pulsating current output from the rectifier circuit,
Switching element, coupling capacitor, discharge lamp load circuit,
Each time a switching element and a high-frequency load current flow, an input current flows with respect to the AC voltage of the AC power supply, and the input current flows other than when the instantaneous value of the pulsating current of the rectifier circuit is low or near the peak value. The input current has the same phase as the power supply voltage because the on / off timings of the opposite switching elements of each group of one side and the opposite switching elements of the other group of the other are the same due to the drive signals of the switch drive control circuit. , The input current waveform approaches the input voltage waveform, the input power factor increases, and the power supply harmonics decrease.

Further, when the current for charging flows through the switching element, the coupling capacitor, the discharge lamp load circuit, the diode, the coil, the charging capacitor and the charging current based on the pulsating current output from the rectifier circuit, the power source is provided because of the coil. A large inrush current is suppressed from flowing into the charging capacitor when the power is turned on.

According to the fourth aspect of the invention, when the switching signals of one of the sets are turned on by the drive signal of the switch drive control circuit, the coil, the switching element and the coupling capacitor are based on the pulsating current output from the rectifying circuit. , Discharge lamp load circuit, switching element and high frequency load current flow, coil, separation diode,
When the charging capacitor is charged by the pulsating flow with the charging capacitor and the switching element, and the opposite switching element of each of the other sets is turned on, the switching element, the discharge lamp load circuit, the coupling capacitor and the switching element based on the charging voltage of the charging capacitor. , Since the diode and high frequency load current flow, based on the pulsating current output from the rectifier circuit, the coil, switching element, coupling capacitor, discharge lamp load circuit, switching element and high frequency load current The input current flows with respect to the voltage, and the input current flows not only when the instantaneous value of the pulsating current of the rectifier circuit is low or near the peak value, but also the input current flows between one pair of opposing switching elements and the other. The opposing switching elements of each set of the above are set by the drive signal of the switch drive control circuit. To flow in the same phase as the power supply voltage by the timing of the respective on-off are the same, the input current waveform approaches the input voltage waveform, the power supply harmonic is reduced with the input power factor becomes higher.

On the basis of the pulsating current output from the rectifier circuit, when the coil, the separation diode, the charging capacitor and the current for charging flow, a large inrush current flows to the charging capacitor when the power is turned on because of the coil. Suppressed.

In a fifth aspect of the invention, a diode for clipping the peak voltage generated on the output side of the rectifying circuit to the applied voltage value of the charging capacitor is connected in parallel to the series circuit composed of the coil and the separation diode. Because of the connection, at the connection point on the rectifier circuit side of the coil, a high-voltage resonance voltage is generated due to the inductance value and stray capacitance of the coil due to the high-frequency current flowing in the coil, but the diode clips the peak voltage of the resonance voltage, Since the withstand voltage of the diode of the rectifier circuit is kept low, it is not necessary to set the withstand voltage of the diode of the rectifier circuit particularly high.

In the sixth aspect of the invention, since a capacitor having a capacity set so as to resonate with the coil at a frequency higher than the circuit operating frequency is connected between the positive and negative output terminals of the rectifier circuit, the rectifier circuit and the coil are connected. It is possible to reduce the high voltage applied to the connection point and reduce the inductance value of the coil.

In the seventh invention, since the partial smoothing circuit is provided instead of the charging capacitor, the voltage charged in the partial smoothing circuit is 1/2 of the voltage output from the rectifier circuit. The withstand voltage of the switching element can be low.

In the eighth invention, in the discharge lamp load circuit, a transformer in which the primary side coil is connected through a capacitor between the connection points of the switching elements of each set,
Since the discharge lamp is connected to the secondary coil of the transformer and the capacitor is connected in parallel, no direct current flows through the discharge lamp, and the life of the discharge lamp load is extended.

In the ninth invention, a coil connected between the AC power source and either one of the power source input terminals of the rectifier circuit or between the negative side output terminal of the rectifier circuit and the ground side is provided. Since the high frequency voltage value applied to the diode of the rectifier circuit is kept low by the coil, it is not necessary to set the withstand voltage of the diode of the rectifier circuit particularly high.

In the tenth aspect of the invention, the switch drive control circuit of the first to ninth aspects of the invention changes the frequency within each half cycle period of the AC power source in accordance with the increase or decrease of the output voltage or the input current of the rectifier circuit. By changing at least one of the drive signal, or the amplitude of the drive signal, by varying the amplitude within each half-cycle period of the AC power supply so as to contradict the increase or decrease of the output voltage or the input current of the rectifier circuit,
In either inverter 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 accordingly the drive signal also becomes narrow when the output voltage is high, or Since the amplitude of the drive signal also changes depending on the level of the output voltage of the rectifier circuit, the boosting ratio for the charging capacitor is consequently reduced and the improper current is also suppressed, and the charging capacitor and switching element have low withstand voltage. The load current ripple is also reduced.

[0028]

【Example】

Example 1. FIG. 1 is a circuit diagram of an inverter device according to a first embodiment of the present invention, and FIG. 2 is a waveform diagram of voltage and current in each part of the inverter device. In the figure, 21 is a commercial AC power supply, 22 is a filter for removing high frequency components, 23 is a rectifier circuit composed of a diode bridge for full-wave rectifying the AC of the commercial AC power supply 21, and 24 is a rectifier circuit 23.
Is a coil for boosting, which is connected to the positive output terminal of the. Two
5 is a separation diode connected in series to the coil 24, 2
A charging capacitor 6 is connected to the positive and negative output terminals of the rectifier circuit 23 via the coil 24 and the separation diode 25 and charges the output of the rectifier circuit 23.

27 and 28 are a pair of switching elements connected in series, one end of which is connected to the anode of the separation diode 25 and the other end of which is connected to the negative output terminal of the rectifying circuit 23, and 29 and 30 of which are connected to the separation diode 25. A pair of switching elements 27, 28, 2 connected in series, one pair of which is connected to the cathode and the other end of which is connected to the negative output terminal of the rectifier circuit 23.
The bridge is composed of 9,30. 31 and 32 are diodes respectively connected in parallel to the pair of switching elements 27 and 28, and 33 and 34 are the pair of switching elements 2
These are diodes connected in parallel to 9 and 30, respectively.
35 is a switch drive control circuit for outputting a high frequency drive signal to the two sets of switching elements 27 to 30, and 36 is a coupling capacitor 40 between the connection points of each pair of switching elements 27, 28 and 29, 30. It is a discharge lamp load circuit connected via. The discharge lamp load circuit 36 includes a fluorescent lamp 37 as a load element, a coil 38 connected in series with the fluorescent lamp 37, and a capacitor 3 connected in parallel with the fluorescent lamp 37.
It is composed of 9 and 9.

Next, the operation of the above embodiment will be described. The AC power supply voltage shown in FIG. 2A through the filter 22 of the AC power supply 21 is rectified by the rectifier circuit 23, and the pulsating current output from the rectifier circuit 23 is the coil 24 and the separation diode 25.
The charging capacitor 26 is charged via the. Then, when the opposite switching elements 28, 29 of each one set are turned on by the drive signal of the switch drive control circuit 35, the switching element 29, the discharge lamp load circuit 36, the coupling capacitor 40, and the The switching element 28 and a high frequency load current flow. Next, when the opposite switching elements 27 and 30 of each of the other sets are turned on, the switching element 27, the coupling capacitor 40, and the coupling capacitor 40, based on the counter electromotive voltage generated in the coil 24 connected to the positive output terminal of the rectifier circuit 23, A high-frequency load current flows through the discharge lamp load circuit 36, the switching element 30, and the charging capacitor 26 is charged via the separation diode 25. Such an operation is alternately repeated. The voltage at the connection point between the coil 24 and the separation diode 25 at this time has the waveform shown in FIG. 2B, and the voltage at the connection point between the separation diode 25 and the charging capacitor 26 has the waveform shown in FIG. 2C. .

Then, each time a high-frequency load current flows through the switching element 27, the coupling capacitor 40, the discharge lamp load circuit 36, and the switching element 30 by the counter electromotive voltage generated in the coil 24, the AC voltage of the AC power source 21 is input. A current flows, and the input current flows not only when the instantaneous value of the pulsating current of the rectification circuit 23 is low or near the peak value, and moreover,
The input current is generated by switching elements 28, 29 facing each other on one side and switching elements 2 facing each other on the other side.
7 and 30 flow in the same phase as the power supply voltage due to the same on / off timing by the drive signal of the switch drive control circuit 35, so that the input current waveform is input as shown in FIG. The voltage waveform approaches, the input power factor increases, and the power supply harmonics decrease. Since the filter 22 is inserted between the commercial 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.

Example 2. FIG. 3 is a circuit diagram of an inverter device according to a second embodiment of the present invention, and FIG. 4 is a waveform diagram of voltages at a charging capacitor and a voltage dividing resistor of the inverter device. In this embodiment, the same components as those in the first embodiment are designated by the same reference numerals, and the description of the duplicated components will be omitted. In this embodiment, a pair of voltage dividing resistors 4 connected in series to the charging capacitor 26.
1, 42 are connected in parallel, and the high potential side of the switching element 29 of the pair of switching elements 29, 30 connected to the cathode of the separation diode 25 and the pair of voltage dividing resistors 4 are connected.
A coupling diode 43 connects between the connection points of 1, 42.

Accordingly, the switching element 29, the discharge lamp load circuit 36, and the coupling capacitor 40 are turned on when the opposing switching elements 28, 29 of each set are turned on.
Also, the charging voltage E1 of the charging capacitor 26 for supplying a high frequency load current to the switching element 28 is equal to the voltage dividing resistor 4
Since the divided voltage E2 is 1, 42 (see FIG. 4), the withstand voltage of the switching elements 28, 29 can be low. Further, along with this, the breakdown voltage of the switching elements 27, 30 can be lowered. The operation and effect of the entire circuit of this embodiment is
It is similar to the embodiment of.

Example 3. FIG. 5 is a circuit diagram of an inverter device according to a third embodiment of the present invention, and FIG. 4 is a waveform diagram of voltage at each part of the inverter device. This example
A rectifier circuit 23 for full-wave rectifying the AC power supply voltage of the AC power supply 21 via a filter 22, a separation diode 25 connected to the positive side output terminal of the rectification circuit 23, and one end of each separation diode 25 connected to both ends. Rectified circuit 2
The switching elements 27 to 30 each having the other end side connected to the negative output terminal of 3 and each pair of two pairs forming a bridge are connected in series, and the pair of switching elements 29 connected to the cathode of the separation diode 25. , 30 connected in parallel, the cathode being located on the high potential side of the switching element 29 and the series-connected diode 47 and the charging capacitor 26, and a switch for outputting a high-frequency drive signal to the two sets of switching elements 27 to 30. Drive control circuit 35
And a pair of switching elements 27, 28 and 29, 3
A discharge lamp load circuit 36 connected via a capacitor 40 between connection points of 0, a connection point of a pair of switching elements 29 and 30 connected to the cathode of the separation diode 25, a diode 47 connected in series, and charging. Capacitor 2
A diode 4 connected in series with the connection point 6
5 and the coil 46. 31-3
Reference numeral 4 is a flywheel diode, and 48 is a bypass capacitor connected in parallel to the diode 47 and the charging capacitor 26 connected in series.

In this embodiment, the switch drive control circuit 3
When the opposing switching elements 27 and 30 of each one set are turned on by the drive signal of 5, the switching element 2 is switched based on the pulsating current output from the rectifier circuit 23.
7, a coupling capacitor 40, a discharge lamp load circuit 36, a switching element 30, and a high-frequency load current flow, and a pulsating current flows from the discharge lamp load circuit 36 to the charging capacitor 26 via the diode 45 and the coil 46 to charge the charging capacitor 2.
6 is charged, and when the opposite switching elements 28 and 29 of the other pair are turned on, the diode 47 and the switching element 2 are based on the charging voltage of the charging capacitor 26.
9, the discharge lamp load circuit 36, the coupling capacitor 40, the switching element 28, and a high-frequency load current flow. Such an operation is alternately repeated. AC power supply 2 at this time
6 has a waveform as shown in FIG. 6A, the output voltage of the rectifier circuit 23 has a waveform as shown in FIG. 6B, and the voltage of the charging capacitor 26 has the coil 46.
The waveform is as shown in (c).

Based on the pulsating current output from the rectifier circuit 23, the switching element 27 and the coupling capacitor 4 are connected.
0, the discharge lamp load circuit 36, the switching element 30, and an input current flows with respect to the power supply voltage of the AC power supply 21 each time a high-frequency load current flows, and the input current is when the instantaneous value of the pulsating current of the rectifier circuit 23 is low. Alternatively, the input current flows to a portion other than near the peak value, and the input current of the switch driving control circuit 35 is the drive signal of the switch driving control circuit 35 between the opposing switching elements 27 and 30 of each one group and the opposing switching elements 28 and 29 of each other pair. Since the ON and OFF timings are the same, the current flows in the same phase as the power supply voltage, so that the input current waveform approaches the input voltage waveform, the input power factor increases, and the power supply harmonics decrease.

Further, based on the pulsating current output from the rectifying circuit 23, the switching element 27, the coupling capacitor 40,
When a current for charging flows through the discharge lamp load circuit 36, the diode 45, the coil 46, the charging capacitor 26,
The presence of the coil 46 prevents a large inrush current from flowing through the charging capacitor when the power is turned on.

Example 4. FIG. 7 is a circuit diagram of an inverter device according to a fourth embodiment of the present invention. In this embodiment, a rectifier circuit 23 for full-wave rectifying an AC power source voltage of an AC power source 21 via a filter 22 and a separation diode 25 connected to a positive output terminal of the rectifier circuit 23 via a coil 24.
And switching elements 27 to 30 in which one end side is connected to both ends of the separation diode 25 and the other end side is connected to the negative side output terminal of the rectifier circuit 23, and two pairs of each pair forming a bridge are connected in series. , Isolation diode 2
A pair of switching elements 2 connected to the cathode of 5
9 and 30 are connected in parallel, and a series connected diode 47 whose cathode is located on the low potential side of the switching element 30.
And the charging capacitor 26 and the two sets of switching elements 2
7 to 30, a switch drive control circuit 35 that outputs a high-frequency drive signal, a pair of switching elements 27,
A discharge lamp load circuit 36 connected via a coupling capacitor 40 between the connection points 28, 29, 30 and a connection point between a pair of switching elements 29, 30 connected to the cathode of the separation diode 25 in series connection. Diode 47
And a diode 45 provided between the charging capacitor 26 and the connection point of the charging capacitor 26.

In this embodiment, when the switching signals 27 and 30 of one of the sets facing each other are turned on by the drive signal 36 of the switch drive control circuit, the coil 24 and the switching circuit are switched based on the pulsating current output from the rectifier circuit 23. A high-frequency load current flows through the element 27, the coupling capacitor 40, the discharge lamp load circuit 36, the switching element 30, and the coil 24, the separation diode 25, the charging capacitor 26, the diode 46, and the switching element 30, and a pulsating current flows to charge the capacitor. 26 is charged, and when the other switching elements 28, 29 of the other pair are turned on, based on the charging voltage of the charging capacitor 26, the switching element 29, the discharge lamp load circuit 36, the coupling capacitor 40, the switching element 28, and a high frequency signal are generated. Load current flows. In this way, based on the pulsating current output from the rectifier circuit 23, the coil 24, the switching element 27, the coupling capacitor 40, the discharge lamp load circuit 36, the switching element 30.
And an input current flows with respect to the power supply voltage of the AC power supply 21 each time a high-frequency load current flows.
When the instantaneous value of the pulsating flow of No. 3 is low or other than near the peak value, the input current thereof is the switching elements 27 and 30 of one of the sets and the switching elements 28 and 29 of the other of the sets which are opposite to each other. Means that since the ON / OFF timings are the same according to the drive signal of the switch drive control circuit 35, the current flows in the same phase as the power supply voltage, so that the input current waveform approaches the input voltage waveform, the input power factor increases, and the power supply increases. Harmonics are reduced. Rectifier circuit 23
Based on the pulsating current output from the coil 24, when the coil 24, the separation diode 25, the charging capacitor 26 and the current for charging flow, the coil 24 prevents the large inrush current from flowing into the charging capacitor when the power is turned on. To be done.

Example 5. FIG. 8 is a circuit diagram of an inverter device according to a fifth embodiment of the present invention, in which a diode 50 is added to the circuit of the first embodiment. That is, a diode 50 for clipping the peak voltage of the high-voltage resonance voltage generated at the output side of the rectifying circuit 23 to the applied voltage value of the charging capacitor 26 is connected in parallel to the series circuit of the coil 24 and the separation diode 25.

In this embodiment, when the diode 50 is not provided, a high frequency voltage is applied to the connection point between the coil 24 and the separation diode 25, so that the connection point between the rectifier circuit 23 and the coil 24 is connected to the coil. When a high-frequency current flows through the coil 24, a high-voltage resonance voltage is generated due to the inductance value and the stray capacitance of the coil 24. For this reason,
The withstand voltage of the diode used for the rectifier circuit 23 is set to the AC power supply
It must be several times greater than the voltage value of 1. here,
By adding the diode 50, the diode 50 clips the peak voltage of the resonance voltage generated at the connection point of the coil 24 on the side of the rectifier circuit 23 to the applied voltage value of the charging capacitor 26, thereby increasing the withstand voltage of the diode of the rectifier circuit 23. In order to keep it low, it is not necessary to set the withstand voltage of the diode of the rectifier circuit 23 particularly high.

Example 6. FIG. 9 is a circuit diagram of an inverter device according to a sixth embodiment of the present invention, in which a capacitor 51 is added to the circuit of the first embodiment. One terminal of the capacitor 51 is connected to the connection point between the positive output terminal of the rectifier circuit 22 and the coil 24, and the other terminal is connected to the negative output terminal of the rectifier circuit 22. That is, the capacitor 5 whose capacitance is set so as to resonate at a frequency higher than the circuit operating frequency with the coil 24 between the positive and negative output terminals of the rectifier circuit 23.
1 is connected. In this embodiment, when the capacitor 48 is not provided, a high-voltage resonance voltage is generated at the connection point between the rectifying circuit 23 and the coil 24. Here, by adding a capacitor 51 whose capacity is set so as to resonate with the coil 24 at a frequency higher than the circuit operating frequency, this high voltage is reduced and the coil 23 is positively tuned to a high frequency via the capacitor 51. A current can be passed to reduce the inductance value of the coil 24. Therefore, by using the coil 24 having an inductance value sufficiently smaller than that of the first embodiment, it is possible to further reduce the size and cost.

Example 7. FIG. 10 is a configuration diagram of an inverter device according to a seventh embodiment of the present invention, in which a partial smoothing circuit 53 including capacitors 54 and 55 and diodes 56, 57 and 58 is connected instead of the capacitor 26 of the circuit of the first embodiment. ing. By connecting the partial smoothing circuit 53 in place of the capacitor 26 as in this embodiment, the voltage charged in the partial smoothing circuit 53 is ½ of the voltage output from the rectifier circuit 23, and thus switching is performed. Elements 27-3
The withstand voltage of 0 is also low.

Example 8. FIG. 11 is a circuit diagram of an inverter device according to an eighth embodiment of the present invention. In place of the coil 38 of the discharge lamp load circuit 36 of the circuit of the first embodiment, one transformer 60 is provided.
The secondary side is connected, and the parallel circuit of the fluorescent lamp 37 and the capacitor 39 is connected to the secondary side of the transformer 60. In this embodiment, the operation is similar to that of the first embodiment, and the input power factor is increased and the power supply harmonics are reduced. Further, for example, when the switching elements 27 and 30 are turned on, a high-frequency current flows through the primary side of the transformer 60 via the coil 24, but the fluorescent lamp 30 is connected to the secondary side and insulated, so that the device There is no risk of electric shock due to, and safety can be improved.

Example 9. FIG. 12 is a circuit diagram of an inverter device according to a ninth embodiment of the present invention, and FIGS. 13 and 14 show a modification of the ninth embodiment. In the circuits shown in FIGS. 12 to 14, the insertion position of the coil 24 of the circuit of the first embodiment is replaced with either one of the power supply terminals of the rectifier circuit 23 or the negative side output terminal of the rectifier circuit 23. 12, the coil 61 is inserted into one power supply terminal of the rectifier circuit 23 in FIG. 12, the coil 62 is inserted into the other power supply terminal of the rectifier circuit 23 in FIG. 13, and the negative side of the rectifier circuit 23 in FIG. The coil 63 is inserted in the output terminal. In this embodiment, the operation is the same as that of the first embodiment and the input power factor is increased and the power source harmonics are reduced, but the coils 61, 62, 63 are used.
Are connected to either one of the power supply terminals of the rectifier circuit 23 or the negative output terminal, the influence of the stray capacitance of these coils can be eliminated.
The rectifier diode of 2 may have a peak value of the high frequency voltage, and a rectifier diode having a low withstand voltage can be used.

Example 10. FIG. 15 is a circuit diagram of an inverter device according to a tenth embodiment of the present invention, FIG. 16 is a circuit diagram showing a configuration of a switch drive control circuit of the device, and FIG. 17 is a graph for explaining the operation of the switch drive control circuit. , FIG. 18
FIG. 3 is a waveform diagram of voltage, current, and inverter drive signal in each part of the inverter device having the same switch drive control circuit. The circuit of this embodiment has a voltage dividing resistor 7 connected in series to the positive and negative output terminals of the rectifier circuit 23 in the circuit of the first embodiment.
1, 72 are connected in parallel, and these connection points are connected to the switch drive control circuit 135 via a connection line 73.
Also, the switch drive control circuit 135 of this embodiment modulates the frequency according to the output voltage of the oscillating circuit 135a that oscillates the drive signal of the predetermined frequency and the rectifying circuit 13, and outputs the drive signal of the amplitude corresponding to the frequency. Frequency bias circuit 13
5b and. The other configuration is the same as that of the first embodiment.

In the first embodiment, the frequency of the drive signal for driving the switching elements 27 to 30 of the switch drive control circuit 35 is constant, that is, fixed, but in this embodiment, between the positive and negative output terminals of the rectifying circuit 23. Since the connection point of the voltage dividing resistors 71 and 72 connected in series provided in the switch drive control circuit 135 is connected to the switch drive control circuit 135 via the connection line 73, the pulsating current output from the rectifier circuit 23 to the switch drive control circuit 135. 18A, the voltage dividing resistor 72 for the output voltage shown in FIG.
The divided voltage by is input. Then, the frequency of the drive signal output from the switch drive control circuit 135 is the frequency modulation circuit 1 with respect to the predetermined frequency of the oscillation circuit 135a.
35b is changed according to the level of the divided voltage as shown in (b) of FIG. 18, and accordingly, (b) of FIG.
As shown in (e), the amplitude of the drive signal is narrow when the divided voltage is high and wide when the divided voltage is low, which is contrary to the height of the divided voltage. 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 27 to 30 are reduced.
Has a low breakdown voltage, and the ripple of load current is small. Note that FIG. 18F shows the waveform of the input current output from the rectifier circuit 23.

In this embodiment, the switch drive control circuit 1
Although the divided voltage of the pulsating flow output voltage output from the rectifying circuit 23 is input to 35, the frequency of the drive signal of the switch drive control circuit 135 is changed according to the level of the divided voltage. Even if the input current output from the rectifier circuit 23 is input to the switch drive control circuit 135, the same effect is produced.

FIG. 19 is a circuit diagram showing the configuration of another switch drive control circuit, FIG. 20 is a graph for explaining the operation of the switch drive control circuit, and FIG. 21 is an inverter device having the switch drive control circuit. It is a wave form diagram of the voltage and the drive signal in each part. When the switch drive control circuit 235 of this embodiment is used in the first embodiment, the pulse width modulation circuit 235b is rectified by the rectifier circuit 2 with respect to the drive signal of the predetermined frequency of the oscillation circuit 235a of the switch drive control circuit 235.
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 conflict with the level of the divided voltage of the output voltage 3. Therefore, the step-up ratio to the 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. 22 is a circuit diagram showing the configuration of another switch drive control circuit, and FIG. 23 is a waveform diagram of drive signals of the switch drive control circuit. If the switch drive control circuit 335 of this embodiment is used in the first embodiment, the frequency of the drive signal output from the switch drive control circuit 335 is the frequency modulation circuit 3 with respect to the predetermined frequency of the oscillation circuit 335a.
The pulse width modulation circuit 335c changes the divided voltage of the output voltage of the rectifier circuit 23 in response to the driving signal from the frequency modulation circuit 335b. When the divided voltage is high, the pulse width of the drive signal is narrowed, and when the divided voltage is low, the pulse width is widened and output. Therefore, since the frequency and the pulse width are changed at the same time according to the level of the divided voltage of the output voltage of the rectifier circuit 23, the boosting ratio for the charging capacitor 26 is further reduced and the load current is also suppressed to be small. And switching elements 31, 3
No. 2 has a low breakdown voltage, and the ripple of the load current is small.

In the above description, FIG. 16 is added to the first embodiment of FIG.
The switch drive control circuits 135 and 2 shown in FIGS.
35 and 335 are used, but the second to ninth examples are used.
In the tenth embodiment, the switch drive control circuit 35 is replaced with the switch drive control circuits 135, 235, and 335 shown in FIGS. It goes without saying that the current can be suppressed to a small level, the withstanding voltage of the charging capacitor and the switching element can be low, and the ripple of the load current can be reduced.

[0052]

According to 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 the switching signals of one of the sets are opposed to each other by the drive signal of the switch drive control circuit. When each element is turned on, a high-frequency load current flows with the switching element, the discharge lamp load circuit, the coupling capacitor and the switching element based on the charging voltage of the charging capacitor, and when the opposite switching element of each of the other sets is turned on, the rectifier circuit Based on the counter electromotive voltage generated in the coil connected to the positive output terminal, the switching element, coupling capacitor, discharge lamp load circuit, switching element and high frequency load current flow, and the charging capacitor is charged via the separation diode. Therefore, the back electromotive force generated in the coil Each time a high-frequency load current flows through the switching element, coupling capacitor, discharge lamp load circuit, or switching element, an input current flows with respect to the AC voltage of the AC power supply, and that input current is when the instantaneous value of the pulsating current in the rectifier circuit is low. Alternatively, the input current flows to other than near the peak value, and the input current of each pair of opposing switching elements on one side and the opposing switching element of each pair on the other side are turned on / off by the drive signal of the switch drive control circuit. Since they are the same, they flow in the same phase as the power supply voltage, so that the input current waveform approaches the input voltage waveform, and the input power factor is increased and the power supply harmonics are reduced.

In the second invention, a pair of voltage dividing resistors connected in series are connected in parallel to the charging capacitor, and the high potential side of a pair of switching elements connected to the cathode of the separation diode and the pair of switching elements. Since a connection diode is used to connect to the connection point of the voltage dividing resistor, a high frequency load is applied to the switching element, the discharge lamp load circuit, the coupling capacitor and the switching element when the opposing switching elements of each one of the above groups are turned on. Since the charging voltage of the charging capacitor for flowing the current is the divided voltage of the voltage dividing resistor, there is an effect that the withstand voltage of the switching element can be low.

In the third aspect of the present invention, when the switching signals of one of the sets are turned on by the drive signal of the switch drive control circuit, the switching element, the coupling capacitor, and the discharge capacitor are discharged based on the pulsating current output from the rectifier circuit. A high-frequency load current flows through the light load circuit, the switching element, and a pulsating current flows through the diode, the switching element, the diode, the coil, and the charging capacitor to charge the charging capacitor, and the other switching element of each pair turns on. Sometimes a high-frequency load current flows with the diode, switching element, discharge lamp load circuit, coupling capacitor and switching element based on the charging voltage of the charging capacitor.Therefore, based on the pulsating current output from the rectifier circuit, the switching element, coupling capacitor, discharge Light load circuit, switch Each time an element and a high-frequency load current flow, an input current flows with respect to the AC voltage of the AC power supply, and the input current 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 has the same phase as the power supply voltage because the on / off timings of the opposite switching elements of each pair of the one side and the opposite switching elements of the other side of the pair are the same due to the drive signals of the switch drive control circuit. Since the current flows, the input current waveform approaches the input voltage waveform, which has the effect of increasing the input power factor and reducing the power supply harmonics.

Further, based on the pulsating current output from the rectifier circuit, when the switching element, the coupling capacitor, the discharge lamp load circuit, the diode, the coil, the charging capacitor and the current for charging flow, the power supply is provided because of the coil. There is also an effect that a large inrush current is suppressed from flowing into the charging capacitor when the power is turned on.

According to the fourth aspect of the present invention, when the switching signal of each one of the sets is turned on by the drive signal of the switch drive control circuit, the coil, the switching element and the coupling capacitor are based on the pulsating current output from the rectifying circuit. , Discharge lamp load circuit, switching element and high frequency load current flow, coil, separation diode,
When a charging capacitor, a diode, and a switching element flow in a pulsating flow to charge the charging capacitor, and the other switching element of each pair turns on, based on the charging voltage of the charging capacitor, the switching element, the discharge lamp load circuit, and the coupling capacitor. Also, since the switching element and the high-frequency load current flow, based on the pulsating current output from the rectifier circuit, the coil, the switching element, the coupling capacitor,
Each time a discharge lamp load circuit, a switching element and a high frequency load current flow, an input current flows with respect to the AC voltage of the AC power supply, and the input current is other than when the instantaneous value of the pulsating current of the rectifier circuit is low or near the peak value. In addition, the input current of each switching element of one set and the opposing switching element of the other set have the same on / off timing by the drive signal of the switch drive control circuit. Since it flows in the same phase as the power supply voltage, the input current waveform approaches the input voltage waveform, which has the effect of increasing the input power factor and reducing the power supply harmonics.

Further, based on the pulsating current output from the rectifier circuit, when the coil, the separation diode, the charging capacitor and the current for charging flow, a large rush current flows in the charging capacitor when the power is turned on because of the coil. It also has the effect of suppressing heat.

In the fifth invention, a diode for clipping the peak voltage generated on the output side of the rectifying circuit to the applied voltage value of the charging capacitor is connected in parallel to the series circuit composed of the coil and the separation diode. Because of the connection, at the connection point on the rectifier circuit side of the coil, a high-voltage resonance voltage is generated due to the inductance value and stray capacitance of the coil due to the high-frequency current flowing in the coil, but the diode clips the peak voltage of the resonance voltage, Since the withstand voltage of the diode of the rectifier circuit is kept low, there is an effect that it is not necessary to set the withstand voltage of the diode of the rectifier circuit particularly high.

In the sixth aspect of the invention, since a capacitor having a capacity set so as to resonate with the coil at a frequency higher than the circuit operating frequency is connected between the positive and negative output terminals of the rectifier circuit, the rectifier circuit and the coil are connected. This has the effect of reducing the high voltage applied to the connection point and reducing the inductance value of the coil.

In the seventh aspect of the invention, since the partial smoothing circuit is provided instead of the charging capacitor, the voltage charged in the partial smoothing circuit is 1/2 of the voltage output from the rectifying circuit. There is an effect that the withstand voltage of the switching element may be low.

In the eighth invention, in the discharge lamp load circuit, the primary side coil is connected through a capacitor between the connection points of the switching elements of each set, and a transformer,
Since it consists of a discharge lamp connected to the secondary coil of the transformer and a capacitor connected in parallel, a high-frequency current flows through the primary side of the transformer, but the discharge lamp is connected to the secondary side and insulated. Therefore, there is no danger of electric shock due to the device, and the safety can be improved.

In the ninth invention, a coil connected between the AC power supply and either one of the power supply input terminals of the rectifier circuit or between the negative output terminal of the rectifier circuit and the ground side is provided. Since the high frequency voltage value applied to the diode of the rectifier circuit is held low by the coil because it is provided, there is an effect that it is not necessary to set the withstand voltage of the diode of the rectifier circuit particularly high.

In the tenth aspect of the invention, the switch drive control circuit of the first to ninth aspects of the invention changes the frequency within each half cycle period of the AC power source in accordance with the increase or decrease of the output voltage or the input current of the rectifier circuit. By changing at least one of the drive signal, or the amplitude of the drive signal, by varying the amplitude within each half-cycle period of the AC power supply so as to contradict the increase or decrease of the output voltage or the input current of the rectifier circuit,
In any of the inverter devices in which the switch drive control circuit in the first to ninth aspects of the present invention, 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. The signal also narrows 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, so the boost ratio to the charging capacitor is reduced and the load current is also reduced. This has the effect that the charging capacitor and the switching element have a low withstand voltage and the ripple of the load current is reduced.

[Brief description of drawings]

FIG. 1 is a circuit diagram of an inverter device according to a first embodiment of the present invention.

FIG. 2 is a waveform diagram of voltage, current and drive signal in each part of the device.

FIG. 3 is a circuit diagram of an inverter device according to a second embodiment of the present invention.

FIG. 4 is a waveform diagram of voltages in a charging capacitor and a voltage dividing resistor of the same device.

FIG. 5 is a circuit diagram of an inverter device according to a third embodiment of the present invention.

FIG. 6 is a waveform diagram of voltage in each part of the device.

FIG. 7 is a circuit diagram of an inverter device according to a fourth embodiment of the present invention.

FIG. 8 is a circuit diagram of an inverter device according to a fifth embodiment of the present invention.

FIG. 9 is a circuit diagram of an inverter device according to a sixth embodiment of the present invention.

FIG. 10 is a circuit diagram of an inverter device according to a seventh embodiment of the present invention.

FIG. 11 is a circuit diagram of an inverter device according to an eighth embodiment of the present invention.

FIG. 12 is a circuit diagram of an inverter device according to a ninth embodiment of the present invention.

FIG. 13 is a circuit diagram of a modified example of the ninth embodiment.

FIG. 14 is a circuit diagram of another modification of the ninth embodiment.

FIG. 15 is a circuit diagram of an inverter device according to a tenth embodiment of the present invention.

FIG. 16 is a circuit diagram showing a configuration of a switch drive control circuit of the device.

FIG. 17 is a graph for explaining the operation of the switch drive control circuit.

FIG. 18 is a waveform diagram of a voltage, a current, and an inverter drive signal in each part of the inverter device having the same switch drive control circuit.

FIG. 19 is a circuit diagram showing a configuration of another switch drive control circuit.

FIG. 20 is a graph for explaining the operation of the switch drive control circuit.

FIG. 21 is a waveform diagram of a voltage and a drive signal in each part of the inverter device having the switch drive control circuit.

FIG. 22 is a circuit diagram showing a configuration of another switch drive control circuit.

FIG. 23 is a waveform diagram of a drive signal of the switch drive control circuit.

FIG. 24 is a circuit diagram of a conventional inverter device.

FIG. 25 is a waveform diagram of an input voltage and an input current in a circuit of a conventional inverter device.

[Explanation of symbols]

 21 AC power supply 23 Rectifier circuit 24 Coil 25 Separation diode 26 Charging capacitor 27 Switching element 28 Switching element 29 Switching element 30 Switching element 35 Switch drive control circuit 36 Discharge lamp load circuit

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Kenji Kimura Inventor Kenji Kimura 2-3 2-3 Marunouchi, Chiyoda-ku, Tokyo Sanryo Electric Co., Ltd.

Claims (10)

[Claims] 1. A rectifying circuit for full-wave rectifying the alternating current of an AC power source, a charging capacitor connected to the positive and negative output terminals of the rectifying circuit via a coil and a separating diode, and one ends of the separating diode are connected to both ends. , A switching element in which each pair of two pairs forming a bridge is connected in series to the negative output terminal of the rectifier circuit, and a high-frequency drive signal is output to the two switching elements. An inverter device comprising a switch drive control circuit and a discharge lamp load circuit connected via a capacitor between connection points of the pair of switching elements. 2. A pair of voltage dividing resistors connected in series to the charging capacitor in parallel, and a high potential side of a pair of switching elements connected to the cathode of the separation diode and the pair of voltage dividing resistors. The inverter device according to claim 1, wherein the points are connected by a coupling diode. 3. A rectifier circuit for full-wave rectifying the alternating current of an AC power source, a separation diode connected to a positive side output terminal of the rectification circuit, and one end side connected to both ends of the separation diode, and the negative side of the rectification circuit. A switching element in which two pairs of each pair forming a bridge are connected in series to the output terminal, and a pair of switching elements connected in series, and connected in parallel to a pair of switching elements connected to the cathode of the separation diode,
A series-connected diode and a charging capacitor whose cathodes are located on the high potential side of the switching element, a switch drive control circuit for outputting a high-frequency drive signal to the two sets of switching elements, and a pair of the switching elements. Between the discharge lamp load circuit connected via a capacitor between the connection points, the connection point of a pair of switching elements connected to the cathode of the separation diode, and the connection point of the diode and the charging capacitor connected in series. An inverter device, comprising: a diode and a coil connected in series, the diode and the coil being connected in series. 4. A rectification circuit for full-wave rectifying the alternating current of an AC power supply, a separation diode connected to the positive side output terminal of the rectification circuit via a coil, and one end of each of the separation diodes connected to one end side of the rectification circuit. The other side of the circuit is connected to the negative side output terminal of the circuit, and two pairs of each pair forming a bridge are connected in series, and a pair of switching elements connected to the cathode of the separation diode are connected in parallel. A series-connected diode and a charging capacitor whose cathode is located on the low potential side of the switching element, a switch drive control circuit for outputting a high-frequency drive signal to the two sets of switching elements, and each pair of the switching elements. Connect the discharge lamp load circuit that is connected via a capacitor between the connection points of the elements and the cathode of the isolation diode. An inverter device comprising: a connection point between the pair of switching elements and a diode provided between the connection point between the series-connected diode and the charging capacitor. 5. A diode for clipping the peak voltage generated on the output side of the rectifier circuit to the applied voltage value of the charging capacitor is connected in parallel to a series circuit composed of the coil and the separation diode. The inverter device for a discharge lamp according to claim 1. 6. The capacitor according to claim 1, wherein a capacitor having a capacitance set so as to resonate with the coil at a frequency higher than a circuit operating frequency is connected between the positive and negative output terminals of the rectifier circuit. Inverter device. 7. The inverter device according to claim 1, wherein a partial smoothing circuit is provided instead of the charging capacitor. 8. The discharge lamp load circuit, wherein the primary side coil is connected via a capacitor between the connection points of the switching elements of each set, and is connected to the transformer and the secondary side coil of the transformer, and the capacitor is connected in parallel. The inverter device according to claim 1, 5, 6, or 7, comprising a connected discharge lamp. 9. A rectifier circuit for full-wave rectifying the alternating current of an AC power supply, a charging capacitor connected to the positive and negative output terminals of the rectifier circuit via a separating diode, and one end of each of the separating diode connected to one end of the rectifying circuit. A switching element in which each pair of two pairs forming a bridge is connected in series to the negative output terminal of the circuit, and a switch drive that outputs a high-frequency drive signal to the two switching elements. A control circuit, a discharge lamp load circuit connected via a capacitor between the connection points of the pair of switching elements, between the power supply input terminal of any one of the AC power supply and the rectifier circuit, or An inverter device comprising a coil connected between a negative side output terminal of a rectifier circuit and a ground side. 10. The drive signal whose frequency is changed by the switch drive control circuit in response to the 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. 7. The method according to claim 2, 3, 4, 5, 6, 7, 8 or wherein at least one of the drive signals is output by varying the output voltage or the input current of the rectifier circuit within a period so as to be contradictory to increase and decrease. 9. The inverter device according to item 9.