JP2007074795A - Power supply - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To expand a conduction angle of an input current, improve a power factor, and acquire a large output using a simple control. <P>SOLUTION: A power supply is provided with rectifying circuits 3a-3d in an AC power supply 1, a reactor 2 connected to the rectifying circuits, first and second switch means 8, 9 for connecting and disconnecting a current path, a power factor improving capacitor 5 connected to the first switch means 8 in series and connected between AC input terminals of the rectifying circuits 3a-3d and a DC output terminal, a phase improving capacitor 6 connected to the second switch means 9 in series and connected between the AC input terminals of the rectifying circuits 3a-3d, a smoothing capacitor 4 for smoothing an output voltage from the rectifying circuits and acquiring a DC voltage, an AC voltage detecting means 32 for detecting a voltage value of the AC power supply 1, and a switch control means 30 for controlling the first and second switch means 8, 9. The switch control means 30 receives a voltage value detected by the AC voltage detecting means 32, and outputs a pulse signal for turning on at least one of the first and second switch means 8, 9. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a power supply device for converting AC to DC and reducing a harmonic component of an input current to improve a power factor.

  Capacitor input type rectifier circuits have been used in various fields as an AC-DC converter circuit in which AC voltage is input to a diode rectifier circuit to obtain a pulsating output, and this is smoothed by a capacitor to obtain a DC voltage. ing. The input current of this circuit has a narrow current conduction angle, a poor power factor, and a large amount of reactive power, so that the power cannot be effectively used, and it contains many harmonic components and is an obstacle to equipment connected to the same power supply system. Is a problem.

  Therefore, a power supply device shown in Patent Document 1 has been studied as a technique for improving the power factor and reducing harmonic components. FIG. 9 is a circuit configuration diagram of the power supply device. The power supply device of FIG. 9 includes an AC input terminal and a DC output terminal of the rectifier circuits 73a to 73d, in addition to a capacitor input circuit composed of an AC power supply 71, a reactor 72, diodes 73a to 73d and a smoothing capacitor 74. A power factor improving capacitor 75 is inserted between them. Reference numeral 80 denotes a load such as a motor drive inverter.

  FIG. 10 shows an example of voltage / current waveforms of the power supply device of FIG. Hereinafter, the operation will be described in detail by dividing one cycle of the AC power supply 71 into four periods with reference to FIG.

  Period 1: There is no charging voltage in the power factor improving capacitor 75, and the AC power source 71 starts to output a positive voltage from zero and, as shown in FIG. 12A, the AC power source 71, the reactor 72, and the power factor improving capacitor 75 The current Iin for charging the voltage Vc of the power factor improving capacitor 75 flows in the order of the diode 73d and the AC power supply 71.

  This operation continues until the power factor improving capacitor 75 is charged and the voltage Vc across the power factor improving capacitor becomes equal to the voltage Vdc across the smoothing capacitor.

  Period 2: Since the voltage value Vac of the AC power supply 71 is larger than the voltage Vdc across the smoothing capacitor, as shown in FIG. 11B, the AC power supply 71, the reactor 72, the diode 73a, the smoothing capacitor 74, the diode 73d, and the AC power supply A current Iin for charging the voltage Vdc of the smoothing capacitor 74 flows in the order of 71.

  In addition to this, the current continues to flow through the path of FIG. 11B until the energy stored in the reactor 72 is released in the periods 1 and 2.

  Period 3: The power factor improving capacitor 75 is charged with the same voltage Vc as the voltage Vdc across the smoothing capacitor, and the AC power supply 71 starts to output a negative voltage from zero, and as shown in FIG. A current Iin for discharging the voltage Vc of the power factor improving capacitor 75 flows in the order of the power source 71, the diode 73c, the smoothing capacitor 74, the power factor improving capacitor 75, the reactor 72, and the AC power source 71.

  This operation continues until the voltage Vc charged in the power factor correction capacitor 75 is discharged to zero.

Period 4: Since the voltage value Vac of the AC power supply 71 is larger than the voltage Vdc across the smoothing capacitor, as shown in FIG. 11D, the AC power supply 71, the diode 73c, the smoothing capacitor 74, the diode 73b, the reactor 72, the AC power supply A current Iin for charging the voltage Vdc of the smoothing capacitor 74 flows in the order of 71.

  In addition to this, current continues to flow through the path of FIG. 11D until the energy stored in the reactor 72 is released in the periods 3 and 4.

  As described above, the current conduction angle is widened by repeating the operations of the periods 1 to 4 for each period of the AC power supply 71, so that the power factor can be improved and the harmonic component contained in the input current Iin can be reduced. it can.

In particular, the energy stored in the reactor 72 in periods 1 and 3 is released in periods 2 and 4, respectively, so that the output voltage of the power supply device, that is, the voltage Vdc of the smoothing capacitor 74 can be increased.
Japanese Patent No. 3377959

  However, although the conventional power supply apparatus shown in FIG. 9 can improve the power factor with a simple configuration, it is necessary to set a large value for the reactor 72 in order to comply with the IEC harmonic regulation. As the load increases, the phase of the current Iin with respect to the voltage value Vac of the AC power supply 71 is delayed, and the power factor decreases, so that there is a problem that the power that can be supplied to the load 80 decreases.

  Further, since the voltage drop due to the reactor 72 is large and the output voltage, that is, the voltage across the smoothing capacitor 74 is lowered, there is a problem that a necessary voltage cannot be obtained as the load 80 increases.

  The present invention solves such a conventional problem, and an object of the present invention is to provide a power supply apparatus that can comply with IEC high frequency regulations and can realize a high power factor and a high output.

  In order to solve the above problems, the present invention provides a rectifier that rectifies an AC power supply voltage and outputs a pulsating voltage, a reactor connected to the rectifier, and a first and a second that connect and cut off a current path. Open / close means, a first open / close means connected in series, a power factor improving capacitor connected between an AC input terminal and a DC output terminal of the rectifier circuit, and a second open / close means connected in series, and rectified. A phase improving capacitor connected between the AC input terminals of the circuit, a smoothing capacitor for smoothing the output voltage of the rectifier circuit to obtain a substantially DC voltage, an AC voltage detecting means for detecting the voltage value of the AC power supply, a first And a switch control means for controlling the second opening / closing means, wherein the switch control means receives a voltage value detected by the AC voltage detection means and turns on at least one of the first and second opening / closing means. And outputs.

  With the above-described configuration, the power factor and the output voltage can be significantly improved, and a power supply device that can meet the IEC harmonic regulations with a simple and inexpensive configuration and can realize a high output can be provided.

  The power supply device of the present invention can achieve high power factor and high output while clearing IEC harmonic regulations.

  According to a first aspect of the present invention, there is provided a rectifier circuit that rectifies an AC power supply voltage to output a pulsating voltage, a reactor connected to the rectifier circuit, and first and second opening / closing means that connect and block a current path; A power factor improving capacitor connected in series with the first switching means and connected between the AC input terminal and the DC output terminal of the rectifier circuit, and an AC input terminal of the rectifier circuit connected in series with the second switch means A phase improving capacitor connected in between, a smoothing capacitor for smoothing the output voltage of the rectifier circuit to obtain a substantially DC voltage, AC voltage detecting means for detecting the voltage value of the AC power supply, and first and second switching Switch control means for controlling the means, and the switch control means receives a voltage value detected by the AC voltage detection means and outputs a pulse signal for turning on at least one of the first and second opening / closing means. is there.

  As a result, it is possible to reliably perform pulse output at an optimal timing with a simple configuration, so that it is possible to provide a power supply device with high power factor, high output, and high reliability. As a result, it is possible to comply with IEC harmonic regulations.

  The second invention further includes a load state detecting means for detecting the magnitude of the load, and the switch control means is one of the first and second opening / closing means according to the magnitude of the load detected by the load state detecting means. The pulse signal is output so that the period during which at least one is turned on changes.

  As a result, a high power factor and a high output can always be realized even when the load fluctuates, so that it is possible to provide a power supply device that can comply with IEC harmonic regulations and has a wide load application range. .

  The third invention further includes power supply frequency detection means for detecting the frequency of the AC power supply voltage, and the switch control means outputs pulses to the first and second opening / closing means according to the frequency detected by the power supply frequency detection means. It changes the on time of the signal.

  As a result, a high power factor and a high output can always be realized regardless of the power supply frequency, so that it is possible to provide a power supply device that can comply with IEC harmonic regulations and has a wide range of power supply and load application. Play.

  The fourth invention further comprises a DC voltage detecting means for detecting the value of the DC voltage, and the switch control means has the first and second open / close states so that the DC voltage detected by the DC voltage detecting means becomes a predetermined value. It controls the means.

  As a result, a high power factor and constant output can always be realized regardless of the load and power supply frequency, and therefore, a power supply apparatus capable of complying with IEC harmonic regulations and supplying a stable output with a wide range of power supply and load application. There is an effect that can be provided.

  According to the air conditioner of the present invention, there is an effect that current utilization is high and high performance can be exhibited.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a circuit configuration diagram showing an embodiment of a power supply device of the present invention. In FIG. 1, 1 is an AC power source, 2 is a reactor for improving the power factor, and 3a to 3d are rectifying elements, which rectify the AC voltage and output a pulsating voltage. 4 is a smoothing capacitor for smoothing the pulsating voltage rectified by the rectifying elements 3a to 3d to obtain a substantially DC voltage, 5 is a power factor improving capacitor for improving the power factor together with the reactor 2, and 6 is for improving the current phase. This is a phase improving capacitor.

  Reference numeral 8 denotes a first switch device connected in series with the power factor improving capacitor 5, and reference numeral 9 denotes a second switch device connected in series with the phase improvement capacitor 6. Here, a semiconductor such as an IGBT or a power MOSFET is used. Consists of switches. Reference numeral 10 denotes a load of the power supply device, which includes a heating wire, an inverter, and a lighting device or a motor that is connected to the inverter and operates. A switch control device 30 controls the first switch device 8 and the second switch device 9, and 32 is an AC voltage detection device that detects the voltage value of the AC power supply 1. Hereinafter, the power supply device of the present invention will be described in detail with reference to FIGS. 1 and 2.

  When the AC voltage detection device 32 detects that the detected absolute value of the voltage value of the AC power supply 1 is greater than a predetermined value, it outputs an AC voltage detection signal to the switch control device 30. When the switch control device 30 receives the AC voltage detection signal, the switch control device 30 outputs a pulse signal for turning on the first switch device 8 and the second switch device 9 for a predetermined time.

  FIG. 2 is a main waveform diagram in the power supply device of the present invention, where Vac is a voltage waveform of the AC power source 1, Iin is a current waveform flowing through the reactor 2, Vc1 is a voltage waveform across the power factor improving capacitor 5, and Vc2 is Voltage waveform at both ends of the phase improving capacitor 6, Vdc is a voltage waveform at both ends of the smoothing capacitor 4, Pac is an AC voltage detection signal of the AC power supply 1 output from the AC voltage detection device 32, and Psw 1 drives the first switch device 8. A pulse signal Psw2 indicates a pulse signal for driving the second switch device 9.

  3 is a current conduction path diagram showing paths through which current flows in each period of the waveform diagram shown in FIG. Hereinafter, the operation in each period will be described in detail with reference to FIGS. 1 to 3.

  Period 1: The voltage Vc1 of the power factor improving capacitor 5 is discharged to some extent during the immediately preceding negative half cycle, and the voltage Vc2 of the phase improving capacitor 6 is charged to approximately -Vdc. When the absolute value of AC power supply 1 exceeds a predetermined value, AC voltage detection device 32 outputs AC voltage detection signal Pac. When the switch control device 30 detects the AC voltage detection signal Pac, the switch control device 30 outputs signals Psw1 and Psw2 for turning on the first switch device 8 and the second switch device 9, respectively.

  After that, the AC power source 1 starts to output a positive voltage, and the voltage Vc2 of the phase improving capacitor 6 is discharged in the order of the AC power source 1, the reactor 2, the phase improving capacitor 6, and the AC power source 1 as shown in FIG. Current Iin flows.

  This operation continues until the voltage Vc2 charged in the phase improving capacitor 6 is discharged to zero and then charged until it reaches the same value as the voltage Vc1 of the power factor improving capacitor 5.

  Period 2: both the power factor improving capacitor 5 and the phase improving capacitor 6 increase the voltage Vac of the AC power source 1 and the AC power source 1, the reactor 2, the power factor improving capacitor 5, and the diode 3d as shown in FIG. In this order, the voltage Vc1 of the power factor improving capacitor 5 is charged in the order of the AC power source 1, and the voltage Vc2 of the phase improving capacitor 6 is charged in the order of the AC power source 1, the reactor 2, the phase improving capacitor 6, and the AC power source 1. A current flows and Iin is the sum of these two currents.

  This operation is continued while the first switch device 8 is in the on state. When the first switch device 8 is in the off state, the power factor correction capacitor 5 is not charged and the current path shown in FIG. Only the phase improving capacitor 6 is charged.

  Period 3: the power supply voltage Vac becomes higher than the voltage Vdc of the smoothing capacitor 4, and the AC power source 1, the reactor 2, the diode 3a, the smoothing capacitor 4, the diode 3d, and the AC power source 1 are smoothed in this order as shown in FIG. A current Iin for charging the voltage Vdc of the capacitor 4 flows. At the end of this period, the second switch device 9 is turned off.

  Period 4: The power factor improving capacitor 5 does not flow because the first switch device 8 is in the off state. In addition, since the voltage of the phase improving capacitor 6 is both charged to approximately Vdc, no current flows. During this period, the energy stored in the reactor 2 in the periods 1, 2, and 3 is released, and as shown in FIG. 3C, the AC power source 1, the reactor 2, the diode 3a, the smoothing capacitor 4, the diode 3d, and the AC power source A current Iin for charging the voltage Vdc of the smoothing capacitor 4 flows in the order of 1.

  Period 5: The voltages of the power factor improving capacitor 5 and the phase improving capacitor 6 are both charged to approximately Vdc. When the AC power source 1 falls below zero and the negative absolute value exceeds a predetermined value, the AC voltage detecting device 32 An AC voltage detection signal Pac is output. When the switch control device 30 detects the AC voltage detection signal Pac, the switch control device 30 outputs signals Psw1 and Psw2 for turning on the first switch device 8 and the second switch device 9, respectively.

  In this period, first, as shown in FIG. 3D, a current Iin for discharging the electric charge of the phase improving capacitor 6 flows in the order of the AC power source 1, the phase improving capacitor 6, the reactor 2, and the AC power source 1. This operation continues until the voltage Vc2 charged in the phase improving capacitor 6 is discharged to zero.

  Period 6: The voltage Vc2 of the phase improving capacitor 6 is discharged to zero, but the voltage Vc1 of the power factor improving capacitor 5 remains charged in a positive half cycle, as shown in FIG. As shown, the AC power source 1, the phase improving capacitor 6, the reactor 2, the current for charging the phase improving capacitor in this order, the AC power source 1, the diode 3c, the smoothing capacitor 4, the power factor improving capacitor 5, and the reactor 2. A current for discharging the power factor correction capacitor 5 flows in the order of the AC power source 1, and Iin is the sum of these two currents.

  This operation is continued while the first switch device 8 is in the on state. When the first switch device 8 is in the off state, the discharge from the power factor correction capacitor 5 is eliminated, and the current path in FIG. Only the phase improving capacitor 6 is charged.

  Period 7: The power supply voltage Vac becomes higher than the voltage Vdc of the smoothing capacitor 4, and the AC power supply 1, reactor 2, diode 3a, smoothing capacitor 4, diode 3d, and AC power supply 1 are smoothed in this order as shown in FIG. A current Iin for charging the voltage Vdc of the capacitor 4 flows. At the end of this period, the second switch device 9 is turned off.

  Period 8: The power factor improving capacitor 5 does not flow because the first switch device 8 is in the off state. Further, since the voltages of the phase improving capacitor 6 are both charged to approximately -Vdc, no current flows. In this period, the energy stored in the reactor 2 in the periods 5, 6 and 7 is released, and as shown in FIG. 3 (f), the AC power source 1, the diode 3c, the smoothing capacitor 4, the diode 3b, the reactor 2, the AC power source A current Iin for charging the voltage Vdc of the smoothing capacitor 4 flows in the order of 1.

As described above, by repeating the operations in the periods 1 to 8 for each cycle of the AC power supply 1, the rising of the input current can be accelerated and a current waveform having a wide conduction angle can be obtained. Therefore, the power factor can be improved and the harmonic component contained in the input current Iin can be reduced.

  In particular, as compared with the conventional power supply device shown in FIG. 9, when the voltage Vac of the AC power supply 1 rises from zero, the current Iin can be made to flow quickly by the discharge current of the phase improving capacitor 6, and further for power factor improvement. By flowing the current Iin relatively gently by the charging / discharging current of the capacitor 5 and the phase improving capacitor 6, a substantially sinusoidal current waveform can be realized as a whole. Thereby, a very high power factor is realizable compared with the past.

  Furthermore, compared with the power supply device shown in FIG. 9, the amount of increase in energy storage in the reactor 2 in the periods 1 and 4 in FIG. 2, and in addition to the power factor improving capacitor 5 in the periods 2 and 5, the phase improving capacitor 6 Since the increase in the energy accumulation in the reactor 2 due to the increase in charging / discharging to is charged in the smoothing capacitor 4 in the periods 3 and 6, a very large output voltage Vdc can be obtained.

  The output voltage Vdc can be controlled by changing the time for which the first switch device 8 and the second switch device 9 are turned on.

  Furthermore, the AC voltage detection device 32 can arbitrarily set the output timing of the AC voltage detection signal by changing the value to be compared with the size of the AC power supply 1, so that the power factor or the magnitude of the output voltage Vdc can be controlled. Can be easily performed.

  As a result, if the circuit constant is selected optimally, the IEC harmonic regulation is cleared and the output can be changed by controlling the on-time of the first switch device 8, so that it can handle loads of various sizes. can do.

  As can be seen from the above description, according to the power supply device of the present invention, it is possible to reliably perform pulse output at an optimum timing, so that a high power factor and a high output are achieved, and a highly reliable power supply device. Can be provided.

(Embodiment 2)
FIG. 4 is a circuit diagram showing still another embodiment of the power supply device of the present invention. The same components as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted. In FIG. 4, reference numeral 20 denotes a load current detection device that detects a current value flowing through the load 10, and is configured by a resistor or the like. Further, the load current detection device 20 outputs the detected value to the switch control device 30. Hereinafter, the power supply device of the present invention will be described in detail with reference to FIG.

  When the load 10 is an inverter and a motor driven at a variable speed by the inverter, the size of the load 10 changes depending on the rotational speed of the motor and the like. Therefore, it is desirable that the power supply device secures a power factor necessary for suppressing harmonics and an output voltage (Vdc) necessary for driving the load 10 in the fluctuation range of the load 10.

  The control device 30 can calculate the size of the load 10 by detecting the voltage Vdc across the smoothing capacitor 4 from the output voltage detection device 21 and the current flowing through the load 10 from the load current detection device 20.

  The switch control device 30 controls the first switch device 8 and the second switch device 9 to be turned on in accordance with the size of the load 10 so as to increase the time. For example, the length of a necessary pulse signal may be stored in advance according to the size of the load 10. FIG. 5 shows an example of a pulse width output from the switch control device 30 to the first switch device 8 and the second switch device 9 with respect to the magnitude of the load.

  As a result, if the circuit constant and the on-time of the first switch device 8 and the second switch device 9 are set optimally, a high power factor can be obtained in the entire region of the load 10 and the load varies in size. Can also respond.

  As can be seen from the above description, according to the power supply device of the present invention, a high power factor and output voltage can always be obtained even when the load fluctuates. Therefore, a power supply device with a wide load application range can be provided. it can.

  The on operation of the first switch device 8 and the second switch device 9 described in the present embodiment is an example, and the operation of the power supply device of the present invention is not limited to this.

(Embodiment 3)
Still another embodiment of the power supply device of the present invention will be described in detail with reference to FIG. In FIG. 4, the AC voltage detection device 32 can have a function of detecting the voltage value of the AC power source 1 and detecting the frequency.

  For example, the detection interval of the predetermined voltage of the AC power source 1 detected by the AC voltage detection device 32 is measured, and if this value is greater than or equal to a predetermined value, it is determined to be 50 Hz, and if it is less than the predetermined value, it is determined to be 60 Hz It can be easily detected.

  The switch control device 30 obtains the timing of the pulse signal output to turn on the first switch device 8 and the second switch device 9 based on the AC voltage detection signal of the AC power supply 1 detected by the AC voltage detection device 32. A pulse signal width to be output is corrected based on the detected frequency of the AC power source 1.

  For example, as shown in FIG. 6, when pulse signal data corresponding to the size of the load 10 at 60 Hz is set in advance and the frequency of the AC power source 1 detected by the AC voltage detection device 32 is 50 Hz. A value obtained by multiplying 60 Hz pulse signal data by (60/50 = 1.2) is output.

  As a result, an optimal pulse signal can be output according to the size of the load 10 when the power supply frequency of the AC power supply 1 is 50 Hz / 60 Hz.

  As can be seen from the above description, according to the power supply device of the present invention, a high power factor and an output voltage can be always obtained regardless of the power supply frequency and the size of the load. An apparatus can be provided.

  The on operation of the first switch device 8 and the second switch device 9 described in the present embodiment is an example, and the operation of the power supply device of the present invention is not limited to this.

(Embodiment 4)
FIG. 7 is a circuit diagram showing still another embodiment of the power supply device of the present invention. The same components as those in FIG. 4 are denoted by the same reference numerals, and detailed description thereof is omitted. In FIG. 7, reference numeral 21 denotes a DC voltage detection device that detects the voltage Vdc across the smoothing capacitor 4 and is constituted by a resistor or the like. Further, the DC voltage detection device 21 outputs the detected value to the switch control device 30. Hereinafter, the power supply device of the present invention will be described in detail with reference to FIG.

  The switch control device 30 controls the power factor of the AC power source 1 and the DC voltage output to the load 10 by turning on and off the first switch device 8 and the second switch device 9.

  Here, the switch control device 30 detects the voltage Vdc across the smoothing capacitor 4 from the DC voltage detection device 21, and turns on the first switch device 8 and the second switch device 9 so that this always becomes a predetermined value. Adjust the period. At this time, by selecting a set value of the output voltage so that the power factor is optimized, it is possible to always maintain a high power factor and a predetermined output voltage even if the load 10 fluctuates.

  As can be seen from the above description, according to the power supply device of the present invention, a high power factor and a stable output voltage can be obtained regardless of the power supply frequency and the size of the load. A power supply device capable of supplying a stable output voltage can be provided.

(Embodiment 5)
FIG. 8 shows an example of the configuration of an air conditioner to which any of the inverter control devices of the present invention is applied. 8, the same components as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted. Hereinafter, the air conditioner of the present invention will be described with reference to FIG.

  As shown in FIG. 8, the air conditioner uses the power supply device of the invention shown in the first embodiment as a compressor drive device. In addition to the inverter device 81 and the electric compressor 82 as the load 10, the indoor unit 92, A refrigeration cycle comprising an outdoor unit 95 and a four-way valve 91 is provided.

  The indoor unit 92 includes an indoor heat exchanger 93 and an indoor fan 94, and the outdoor unit 95 includes an outdoor heat exchanger 96, an outdoor fan 97, and an expansion valve 98.

  During the refrigeration cycle, a refrigerant that is a heat medium circulates. The refrigerant is compressed by the electric compressor 82, and heat is exchanged with the outdoor air by blowing from the outdoor blower 97 in the outdoor heat exchanger 96, and indoor air is blown from the indoor blower 94 in the indoor heat exchanger 93. And heat exchange. Indoor air conditioning is performed by the air after heat exchange in the indoor heat exchanger 93. Switching between cooling and heating is performed by reversing the direction of refrigerant circulation by a four-way valve 91.

  The circulation of the refrigerant in the refrigeration cycle as described above is performed by driving the electric compressor 82 by the inverter device 81, and the control method of the inverter device 81 and the electric compressor 82 is the power source of the first embodiment. This is done using a device. Since the configuration and operation of the power supply device are as described above, description thereof will be omitted.

  With the configuration as described above, it is possible to suppress deterioration in control performance such as a decrease in efficiency in the air conditioner.

  In the present embodiment, the air conditioner using the power supply device of the invention shown in the first embodiment as the compressor driving device has been described. However, the power supply device of another invention as shown in the second or fourth embodiment is used. Even if it uses, the air conditioner which had the effect which the power supply device of each invention has similarly can be provided.

  Therefore, the effect of the power supply apparatus according to the present invention can be fully utilized by using it particularly for an air conditioner with a large load change.

  As described above, the power supply device according to the present invention can realize a high power factor and a high output, and therefore can be applied to uses such as an outdoor unit of an air conditioner.

The circuit block diagram in one Example of the power supply device of this invention Main waveform diagram in another embodiment of the power supply device of the present invention (a) to (f) are current path diagrams in another embodiment of the power supply device of the present invention. The circuit block diagram in the further another Example of the power supply device of this invention The graph which shows the pulse width of the switch drive signal with respect to the magnitude | size of load in further another Example of the power supply device of this invention The graph which shows the pulse width of the switch drive signal with respect to the magnitude | size of load in further another Example of the power supply device of this invention The circuit block diagram in the further another Example of the power supply device of this invention Configuration of the air conditioner of the present invention Circuit diagram of conventional power supply Main waveform diagram of conventional power supply Current path diagram of conventional power supply

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 AC power supply 2 Reactor 3a, 3b, 3c, 3d Rectifier 4 Smoothing capacitor 5 Power factor improvement capacitor 6 Phase improvement capacitor 8 First switch device 9 Second switch device 10 Load 20 Load current detection device 21 DC voltage Detection device 30 Switch control device 32 AC voltage detection device

Claims (5)

A rectifier circuit that rectifies an AC power supply voltage and outputs a pulsating voltage, a reactor connected to the rectifier circuit, first and second opening / closing means for connecting and blocking a current path, and the first opening / closing means Connected in series with the power factor improving capacitor connected between the AC input terminal and the DC output terminal of the rectifier circuit, and connected in series with the second switching means, and between the AC input terminals of the rectifier circuit. A connected phase improving capacitor; a smoothing capacitor that smoothes the output voltage of the rectifier circuit to obtain a substantially DC voltage; AC voltage detection means that detects a voltage value of an AC power supply; and the first and second open / close switches Switch control means for controlling the means, and the switch control means receives a voltage value detected by the AC voltage detection means and turns on at least one of the first and second switching means. Power supply and outputs a degree. Load state detection means for detecting the magnitude of the load is further provided, and the switch control means includes at least one of the first and second opening / closing means according to the magnitude of the load detected by the load state detection means. The power supply device according to claim 1, wherein a pulse signal is output so that a period during which the switch is turned on is changed. Power supply frequency detection means for detecting the frequency of the AC power supply voltage is further provided, and the switch control means is an on-time of a pulse signal output to the first and second opening / closing means according to the frequency detected by the power supply frequency detection means The power supply device according to claim 1, wherein the power supply device is changed. DC voltage detecting means for detecting the value of the DC voltage is further provided, and the switch control means controls the first and second opening / closing means so that the DC voltage detected by the DC voltage detecting means becomes a predetermined value. The power supply device according to claim 1, wherein the power supply device is a power supply device. An air conditioner comprising the power supply device according to any one of claims 1 to 4.

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