JP2011193718A - Power supply device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power supply device capable of preventing noise or abnormal sound. <P>SOLUTION: The power supply device includes a rectifier circuit 20 for rectifying an AC voltage, a filter 12 having coils 121, 122 intervened in respective electric paths on the input side of the rectifier circuit 20, a switching circuit 15 for short-circuiting either of the coils and closing or opening either of the electric paths of the input side of the filter to switch a first state or a second state, and a rectifier circuit 52 formed on the input side of the switching circuit 15. The switching circuit 15 applies a current to each of the coils in the first state to supply the voltage rectified by the rectifier circuit 20 to power supply units 40, 50 respectively, and supplies the voltage rectified by the rectifier circuit 52 to the power supply unit 50 in a state where the coils are short-circuited by the short circuit in the second state. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a power supply device that converts an AC voltage into a DC voltage, and in particular, includes a plurality of power supply units, and outputs power from each power supply unit during normal times and outputs power from some power supply units during standby. Relates to the device.

  As a power supply device that is incorporated in electrical equipment or electronic equipment and supplies the required voltage to the load, the AC voltage is rectified and smoothed, and the smoothed voltage is converted to the required voltage by a power supply unit such as a switching circuit. Is used in various fields. Further, depending on the load capacity, a relatively large capacity power supply device is also required.

  On the other hand, to save power, the power supply unit is divided into a main power supply unit and an auxiliary power supply unit. During normal operation (normal operation), power is supplied to the load by both the main power supply unit and the auxiliary power supply unit. In addition to responding to the demand for larger capacity, power supply devices that can stop the operation of the main power supply unit and supply power to the load only by the auxiliary power supply unit are also used during standby to operate only a part of the load. .

  As an example of power saving, two half-wave rectifier circuits composed of two diodes are provided, a relay switch is provided on the input side of each half-wave rectifier circuit, and two relay-type switches are provided during normal operation. A power supply that can reduce power consumption during standby by closing both switches to form a full-wave rectifier circuit and, in standby, only one relay-type switch is closed to form a half-wave rectifier circuit. An apparatus is disclosed (Patent Document 1).

  A power supply device used for an electric device or an electronic device includes a smoothing capacitor corresponding to a capacity in order to rectify and smooth an AC voltage. The current waveform is distorted by the steep current flowing to the smoothing capacitor, and a harmonic component is generated. When such a distorted current flows in the commercial power supply line, it may cause a failure of other equipment. Therefore, it is necessary to provide a harmonic suppression circuit for suppressing the generation of harmonic components in the power supply device. In particular, the higher the capacity of the power supply device, the more important it is to suppress harmonic components. However, the power supply device of Patent Document 1 does not disclose suppression of harmonics.

  When a conventional power supply device includes a harmonic suppression circuit, several examples are conceivable. FIG. 9 is a block diagram showing an example of the configuration of a conventional power supply apparatus 300. As shown in FIG. 9, the conventional power supply device 300 includes a main power supply unit 40 and an auxiliary power supply unit 50, and power is supplied to the loads 200 and 210 by the main power supply unit 40 and the auxiliary power supply unit 50, respectively. Supply. In the standby state in which power is supplied only to some of the loads 210, power is supplied only by the auxiliary power supply unit 50.

  The circuit configuration on the main power supply unit 40 side includes an open / close switch 61 that opens and closes an AC voltage from a commercial power supply, a common mode choke coil 62 for removing common mode noise, and an across the line capacitor 13 for removing normal mode noise. A full-wave rectifier circuit 20 in which four diodes are bridge-connected, a harmonic suppression circuit 30, a smoothing capacitor 63, and the like are provided. The harmonic suppression circuit 30 can be constituted by, for example, a choke coil 31, an FET 32, a diode 33, and the like. The circuit configuration on the auxiliary power supply unit 50 side includes a full-wave rectifier circuit 20 connected to the previous stage (input side) of the open / close switch 61, a smoothing capacitor 64, and the like.

  The operation of the power supply apparatus 300 illustrated in FIG. 9 is as follows. In normal times, the open / close switch 61 is closed. Thereby, in normal time, the main power supply unit 40 and the auxiliary power supply unit 50 supply power to the loads 200 and 210, respectively. Further, the open / close switch 61 is opened during standby. Thereby, at the time of standby, electric power is supplied to the load 210 only by the auxiliary power supply unit 50.

JP 2009-268284 A

  A power supply apparatus according to a first aspect of the present invention includes a first state in which a plurality of power supply units are provided, receive AC voltage, and power is supplied to a load by each power supply unit, and power is supplied from a part of the power supply unit. A first rectifier circuit that rectifies an alternating voltage, a filter having a coil interposed in each electric circuit on the input side of the first rectifier circuit, and one of the coils A short circuit for short-circuiting, a switching circuit for switching the first state or the second state by closing or opening one of the electric circuits on the input side of the filter, and a second circuit provided on the input side of the switching circuit A rectifier circuit, and the switching circuit supplies a current rectified by the first rectifier circuit to each coil in the first state and supplies the voltage rectified by the first rectifier circuit to the power supply unit. In the state where the coil is short-circuited by a short circuit, the second adjustment is performed. Characterized in that the voltage rectified in the circuit is arranged to supply to a part of the power supply unit.

  A power supply device according to a second invention is the power supply device according to the first invention, wherein the power supply unit supplies power to a plurality of loads in the first state, and one of the plurality of loads in the second state. The power is supplied to the unit.

  According to a third aspect of the present invention, there is provided the power supply device according to the first or second aspect, wherein the second rectifier circuit includes a coil different from the coil in which the rectified voltage is short-circuited by the short-circuit in the second state. It is comprised so that it may supply to a part of said power supply part via.

  In the first invention, a first rectifier circuit for rectifying an alternating voltage, a filter having a coil interposed in each of the electric circuits on the input side of the first rectifier circuit, and a short circuit for short-circuiting one of the coils And a switching circuit for switching the first state or the second state by closing or opening one electric circuit on the input side of the filter, and a second rectifier circuit provided on the input side of the switching circuit. The switching circuit supplies current to each coil in the first state, supplies the voltage rectified by the first rectifier circuit to each power supply unit, and in a state where the coil is short-circuited by the short circuit in the second state. The voltage rectified by the rectifier circuit is supplied to a part of the power supply unit.

  For example, a coil is interposed in each electric circuit on the input side of the first rectifier circuit, and a filter for reducing common mode noise is provided. The second rectifier circuit performs half-wave rectification via one electric circuit that is not opened / closed by an opening / closing element, and is short-circuited so as to short-circuit the coil interposed in the other electric circuit in the second state (during standby). Provide a circuit. In normal time (first state), the switching element closes the electric circuit, so that the filter removes common mode noise conducted in the same phase in each electric circuit. During standby (second state), a half-wave rectified current flows through the first coil interposed in one electric circuit that is not opened and closed by the switching element. At this time, since the switching element is open, no current flows through the second coil interposed in the other electrical path. Since the current flows only through one of the first coils of the filter, the magnetic flux cannot be canceled and the impedance (inductance) increases. For this reason, a current flowing only in the first coil causes a vibration of the coil (winding) or a distortion of the magnetic core, and noise or abnormal noise is generated. By short-circuiting the second coil with a short circuit, an electromotive force is generated in the second coil by the magnetic flux generated by the current flowing in the first coil, and a current is also passed through the second coil by the generated electromotive force. Thereby, it is possible to reduce the inductance of the filter and prevent the generation of noise or abnormal noise.

  In addition, for example, a short circuit that short-circuits a coil interposed in one electric circuit that is not opened and closed by the opening and closing element in the second state (standby) is provided. The second rectifier circuit performs half-wave rectification by bypassing the coil with a short circuit. In normal time (first state), the switching element closes the electric circuit, so that the filter removes common mode noise conducted in the same phase in each electric circuit. In the second state (standby), a half-wave rectified current is passed by bypassing a coil interposed in one electric circuit that is not opened / closed by an opening / closing element by a short circuit. As a result, no current flows through any coil of the filter during standby. That is, if a current flows through only one coil of the filter, the magnetic flux cannot be canceled and the impedance (inductance) increases, and the current flowing through only one coil causes the vibration of the coil (winding) or the magnetic core. Vibration due to distortion or the like occurs, and noise or abnormal noise is generated. Such a situation can be prevented.

  In the second invention, the power supply unit supplies power to the plurality of loads in the first state, and supplies power to some of the plurality of loads in the second state.

  In the third invention, the second rectifier circuit supplies the rectified voltage to a part of the power supply unit via a coil different from the coil short-circuited by the short circuit in the second state.

  According to the present invention, it is possible to prevent generation of noise or abnormal noise generated in the filter during standby.

It is a block diagram which shows an example of a structure of the power supply device of this Embodiment. It is a block diagram which shows an example of a structure of the power supply device of this Embodiment. FIG. 6 is a block diagram illustrating an example of a configuration of a power supply device according to a second embodiment. FIG. 6 is a block diagram illustrating an example of a configuration of a power supply device according to a second embodiment. FIG. 10 is a block diagram illustrating another example of the configuration of the power supply device according to the second embodiment. FIG. 10 is a block diagram illustrating another example of the configuration of the power supply device according to the second embodiment. FIG. 10 is a block diagram illustrating another example of the configuration of the power supply device according to the second embodiment. FIG. 10 is a block diagram illustrating another example of the configuration of the power supply device according to the second embodiment. It is a block diagram which shows an example of a structure of the conventional power supply device.

Embodiment 1
DESCRIPTION OF EMBODIMENTS Hereinafter, a power supply device according to the present invention will be described with reference to the drawings illustrating embodiments. 1 and 2 are block diagrams illustrating an example of the configuration of the power supply apparatus 110 according to the present embodiment. FIG. 1 shows a state in a normal state (first state), and FIG. 2 shows a state in a standby state (second state). The standby state refers to a state in which only a part of the load is operated, for example. The power supply device 110 includes a main power supply unit 40 and an auxiliary power supply unit 50, and supplies power to the loads 200 and 210 by the main power supply unit 40 and the auxiliary power supply unit 50, respectively, during normal operation (normal operation). In the standby state in which power is supplied only to some of the loads 210, power is supplied to the load 210 only by the auxiliary power supply unit 50.

  The power supply device 110 receives AC voltage from the commercial power source 1 (for example, AC 100 V, AC 200 V, etc.), and supplies the received AC voltage to the circuit on the main power supply unit 40 side and the circuit on the auxiliary power supply unit 50 side. The main power supply unit 40 and the auxiliary power supply unit 50 are switching power supplies having a switching circuit, for example. The circuit configuration of the main power supply unit 40 and the auxiliary power supply unit 50 may be any circuit configuration.

  The circuit on the main power supply unit 40 side includes an opening / closing element 11 that opens and closes one side of an electric circuit (power supply line) that receives an AC voltage, and coils 121 and 122 that are provided in the subsequent stage of the opening / closing element 11 and are interposed in each electric circuit. , A filter 12 for removing common mode noise, an across-the-line capacitor 13 for removing normal mode noise, a downstream of the filter 12, and a bridge-connected four Diode bridge 20 as a first rectifier circuit having diodes 21, 22, 23, 24, a harmonic suppression circuit 30 provided on the output side (rear stage) of diode bridge 20 to suppress harmonic components, and harmonic suppression circuit 30 And a smoothing capacitor 41 as a first smoothing capacitor provided on the input side of the main power supply unit 40. Equipped with a etc..

  The circuit on the auxiliary power supply unit 50 side includes a diode 52 as a second rectifier circuit having an anode connected to one of the electric circuits (power supply lines) for receiving an AC voltage, and a second provided on the input side of the auxiliary power supply unit 50. A smoothing capacitor 51 as a smoothing capacitor, a diode 53 having an anode connected to one end (positive side end) on the output side of the harmonic suppression circuit 30 and a cathode connected to the input end (positive side end) of the auxiliary power supply unit 50, etc. Is provided.

  In response to a signal (indicated by a broken line output from the load 210 in the examples of FIGS. 1 and 2) output from a control circuit that controls normal operation and standby operation such as a microprocessor (not shown) An opening / closing element 11 as a switching circuit for switching between time and standby opens and closes the electric circuit. At the normal time shown in FIG. 1, the switching element 11 closes the electric circuit. Further, at the time of standby shown in FIG. 2, the switching element 11 opens the electric circuit. As the switching element 11, a contact relay, a contactless relay, or the like can be used. Further, a semiconductor switch such as an IGBT, a transistor, or an FET can be used as the switching element 11.

  The filter 12 is a so-called common mode choke coil, and with respect to common mode noise that conducts each electric circuit in the same phase, high impedance is obtained by adding magnetic flux due to the common mode current, and the common mode noise is prevented from conducting. To do. Further, the filter 12 has a low impedance with respect to the normal mode current because the magnetic fluxes generated by the coils 121 and 122 cancel each other.

  When supplying the voltage rectified by the full wave in the diode bridge 20 to the main power supply unit 40 and the auxiliary power supply unit 50, a steep charging current flows through the smoothing capacitors 41 and 51, so that the frequency is an integral multiple of 50 Hz or 60 Hz in the electric circuit. Harmonic current (distortion current) containing components flows. When such a distorted current flows, the power loss of other devices connected to the commercial power source 1 increases, and the other devices fail or useless power consumption increases. The harmonic suppression circuit 30 suppresses such harmonic current.

In the harmonic suppression circuit 30, a coil (inductor) 31 and a diode 33 are connected in series, and an FET 32 is connected to a connection point between the coil 31 and the diode 33, and PFC (Power Factor Correction: power factor improvement by switching). ) Circuit. Note that the configuration of the harmonic suppression circuit 30 is not limited to the configuration illustrated in FIG. 1, and a choke input type that increases the conduction angle by the choke coil as long as the current waveform can be approximated to a sine wave shape. Other circuit configurations such as a rectifier circuit may be used.

  Next, the operation of the power supply device 110 of the present embodiment will be described. As shown in FIG. 1, in normal times, the switching element 11 closes the electric circuit. That is, during normal operation, the voltage rectified by the diode bridge 20 is supplied to the main power supply unit 40 and the auxiliary power supply unit 50 via the harmonic suppression circuit 30. Under normal conditions, the voltage rectified by the diode bridge 20 is supplied to the main power supply unit 40 and the auxiliary power supply unit 50 through the harmonic suppression circuit 30, so that the smoothing capacitor 41 on the input side of the main power supply unit 40 and the auxiliary power supply are supplied. The harmonic component generated by the distorted current waveform to the smoothing capacitor 51 on the input side of the unit 50 can be suppressed.

  As shown in FIG. 2, at the time of standby, the switching element 11 opens an electric circuit. That is, during standby, an AC voltage is not applied to the diode bridge 20, and the voltage rectified by the diode 52 is supplied to the auxiliary power supply unit 50 without going through the harmonic suppression circuit 30. During standby, the voltage rectified by the diode 52 is applied to the auxiliary power supply unit 50, and current flows to the auxiliary power supply unit 50. The feedback current from the auxiliary power supply unit 50 flows to the commercial power supply 1 side via the diode 23.

  During standby, the voltage rectified by the diode 52 is supplied to the auxiliary power supply unit 50, and power is not supplied to the diode bridge 20, the harmonic suppression circuit 30, the smoothing capacitor 41, and the main power supply unit 40. In addition, power consumption during standby can be reduced. Thus, at the normal time, since the harmonic suppression circuit 30 functions in both the main power supply unit 40 and the auxiliary power supply unit 50, even when the load increases, the harmonics can be sufficiently suppressed. Further, during standby in which only a part of the load is operated, power supply to the circuit on the main power supply unit 40 side can be cut off, so that standby power can be reduced and harmonics can be achieved while saving power. Suppression can be realized.

  Further, since full-wave rectification is performed by the diode bridge 20 and half-wave rectification is performed by the diode 52, the auxiliary power supply unit 50 can be operated by half-wave rectification of the AC voltage during standby, further reducing power consumption during standby. can do.

  Further, in normal times, the switching element 11 closes the electric circuit, so that the AC voltage is full-wave rectified by the diode bridge 20, and the main power supply unit 40 and the auxiliary power supply unit 50 are operated through the harmonic suppression circuit 30. On the other hand, at the time of standby, the switching element 11 opens the electric circuit, so that half-wave rectification is performed by the diode 52 and only the auxiliary power supply unit 50 is operated. Thereby, harmonic suppression can be realized while reducing standby power.

  There is a relatively large difference in power supplied from the auxiliary power supply 50 to the load 210 between the normal time and the standby time. When the standby time is 1, the normal time is 20 to 30, for example. For example, the power supplied by the auxiliary power supply unit 50 during normal operation is 20 W, and is 1 W or less during standby. As described above, since the power supplied from the auxiliary power supply unit 50 during standby is smaller than that during normal operation, the influence of harmonics can be ignored during standby, and the function of the harmonic suppression circuit is not particularly required. However, normally, since the auxiliary power supply unit 50 is responsible for supplying a considerable amount of power, the influence of harmonics cannot be ignored. However, by adopting the configuration of the present embodiment, harmonics can be suppressed.

  In the present embodiment, the harmonic suppression circuit 30 can be used in common for both the operation of the main power supply unit 40 and the operation of the auxiliary power supply unit 50 during normal operation to suppress harmonics. For this reason, compared with the case where a separate harmonic suppression circuit is provided in the main power supply unit and the auxiliary power supply unit, in this embodiment, the number of parts can be reduced, the cost can be reduced, and the apparatus can be downsized. . For example, when the harmonic suppression circuit 30 similar to the present embodiment is provided on the input side of the main power supply unit and the choke coil is provided separately from the harmonic suppression circuit 30 on the input side of the auxiliary power supply unit, the auxiliary power supply unit is Since a larger amount of power is supplied to the load at the normal time than at the standby time, a large choke coil is required to suppress the generation of harmonics. In the present embodiment, since the harmonic suppression circuit 30 is shared by the main power supply unit 40 and the auxiliary power supply unit 50, a large choke coil is not required separately.

  In the present embodiment, by providing the diode 53, the input voltage of the auxiliary power supply unit 50 can be supplied from the smoothing capacitor 41 for the main power supply unit 40. As a result, the smoothing capacitor 51 for the auxiliary power supply unit 50 has a capacity sufficient to secure a capacity for the load during standby, and a small capacitor with a small capacity can be used. Miniaturization and cost reduction can be achieved.

  In the present embodiment, since the opening / closing element 11 is provided in front of the across-the-line capacitor 13, there is no risk of electric shock from the electric charge stored in the across-the-line capacitor 13 by opening the electric circuit with the opening / closing element 11. This eliminates the need for a discharge resistor for discharging the charge charged in the across-the-line capacitor 13. Thereby, the power loss due to the discharge resistance is eliminated, and the power consumption can be reduced.

Embodiment 2
3 and 4 are block diagrams showing an example of the configuration of the power supply device 120 according to the second embodiment. FIG. 3 shows a state in a normal state (first state), and FIG. 4 shows a state in a standby state (second state). The difference between the second embodiment and the first embodiment described above is that an opening / closing element 15 is provided instead of the opening / closing element 11. The switching element 15 has contacts 151, 152, and 153. The contact 151 is connected to the electric circuit on the AC power supply 1 side, the contact 153 is connected to the input side of the coil 121 of the filter 12, and the contact 152 is connected to the output side of the coil 121.

  As shown in FIG. 3, at the normal time, the contact 151 and the contact 153 are closed, and the contact 152 and the contact 153 are opened. Further, as shown in FIG. 4, at the time of standby, the contact 151 and the contact 153 are opened, and the contact 152 and the contact 153 are closed. That is, as shown in FIG. 3, the AC voltage from the commercial power supply 1 is normally supplied to the main power supply unit 40 and the auxiliary power supply unit 50 through the filter 12, the diode bridge 20, and the harmonic suppression circuit 30 as shown in FIG. 3. In this case, both ends of the coil 121 of the filter 12 are opened.

  On the other hand, as shown in FIG. 4, during standby, the AC voltage from the commercial power source 1 is supplied to the auxiliary power supply unit 50 through the diode 52. In this case, both ends of the coil 121 of the filter 12 are short-circuited by the switching element 15. That is, the open / close element 15 has a function as a short circuit to short-circuit the coil 121 interposed in the electric circuit during standby.

  The reason for short-circuiting both ends of one coil 121 of the filter 12 during standby is as follows. That is, during standby, a half-wave rectified current flows through the diode 52, the diode 23 of the diode bridge 20, and the coil 122 interposed in one electric circuit that is not opened and closed by the switching element 15. At this time, since the contacts 151 and 153 of the switching element 15 are open, no current flows through the coil 121 interposed in the other electrical path. Since current flows only through one coil 122 of the filter 12, the magnetic flux cannot be canceled and the coil 122 has high impedance. For this reason, the current flowing only in one coil 122 causes vibration of the coil 122 (winding) or vibration due to distortion of the magnetic core, and noise or abnormal noise is generated. Since the current flowing through the coil 122 is a current obtained by half-wave rectifying an AC voltage, it includes a harmonic component having a fundamental wave of 100 Hz or 120 Hz, and thus becomes an audible frequency range.

  In the second embodiment, the power supply device 120 generates an electromotive force in the coil 121 by the magnetic flux generated by the current flowing through the coil 122 by short-circuiting both ends of the coil 121 where current does not flow during standby with a short circuit (opening / closing element 15). Then, a current is caused to flow in a closed loop composed of the coil 121 and the contacts 152 and 153 by the generated electromotive force. Thereby, the coil 122 becomes a low impedance and generation | occurrence | production of a noise or unusual noise can be prevented.

  The switching element 15 can be a two-contact relay. Further, similarly to the switching element 11, a semiconductor switch such as an IGBT, a transistor, or an FET can be used.

  5 and 6 are block diagrams showing other examples of the configuration of the power supply device 130 according to the second embodiment. FIG. 5 shows a normal state (first state), and FIG. 6 shows a standby state (second state). The difference from the configuration illustrated in FIGS. 3 and 4 is that two switching elements 11 and 16 are provided instead of the switching element 15. The opening / closing element 11 is the same as that of the first embodiment. The opening / closing element 16 has a function as a short circuit for short-circuiting the coil 121 during standby. Similarly to the switching element 11, the switching element 16 can be a contact relay, a non-contact relay, or a semiconductor switch such as an IGBT, a transistor, or an FET.

  Note that the operation of the power supply apparatus 130 is the same as that in the example of FIGS. In the power supply device 130, an electromotive force is generated in the coil 121 by the magnetic flux generated by the current flowing in the coil 122 by short-circuiting both ends of the coil 121 in which no current flows during standby with a short circuit (opening / closing element 16). Thus, a current is caused to flow in a closed loop constituted by the coil 121 and the switching element 16. Thereby, the coil 122 becomes a low impedance and generation | occurrence | production of a noise or unusual noise can be prevented.

  7 and 8 are block diagrams showing another example of the configuration of the power supply device 140 according to the second embodiment. FIG. 7 shows a state in a normal state (first state), and FIG. 8 shows a state in a standby state (second state). The difference from the configuration illustrated in FIG. 5 and FIG. 6 is that the switch elements 11 and 16 are provided in common, but the switch element 16 is provided on both sides of the coil 122 instead of on both sides of the coil 121.

  As shown in FIG. 7, in a normal time, the switching element 11 is closed and the switching element 16 is opened. Further, as shown in FIG. 8, at the time of standby, the opening / closing element 11 is opened and the opening / closing element 16 is closed. That is, as shown in FIG. 7, the AC voltage from the commercial power supply 1 is supplied to the main power supply unit 40 and the auxiliary power supply unit 50 through the filter 12, the diode bridge 20, and the harmonic suppression circuit 30 during normal times. In this case, both ends of the coil 122 of the filter 12 are opened.

  On the other hand, as shown in FIG. 8, during standby, the AC voltage from the commercial power supply 1 is supplied to the auxiliary power supply unit 50 through the diode 52. In this case, both ends of the coil 122 of the filter 12 are short-circuited by the switching element 16. That is, the opening / closing element 16 has a function as a short circuit to short-circuit the coil 122 interposed in the electric circuit during standby.

  As shown in FIG. 8, during standby, a half-wave rectified current flows through the diode 23 and the switching element 16 of the diode bridge 20. That is, the coil 122 is bypassed by the switching element 16 and no current flows through the coil 122. As a result, it is possible to prevent the generation of noise or abnormal noise due to current flowing through only one coil of the filter 12 during standby.

  As described above, in the first and second embodiments, harmonic suppression can be achieved during normal times, and standby power can be reduced during standby.

  Further, the harmonic suppression circuit 30 can be shared by the main power supply unit 40 and the auxiliary power supply unit 50, and the simple configuration of only the switching element 11 and the diodes 52 and 53 for opening and closing one side of the electric circuit reduces costs and saves power. It is possible to reduce the size by making space.

  In addition, since half-wave rectification is performed only through the diode 52 and the diode 23 of the diode bridge 20 during standby, power loss is small and power consumption during standby can be reduced.

  In addition, when noise or abnormal noise is generated in the filter 12 during standby, the generation of noise or abnormal noise can be prevented with a simple configuration.

  In the above-described embodiment, the short circuit that short-circuits one coil of the filter 12 during standby is not always necessary and can be omitted if the capacity of the power supply device is relatively small.

11 Open / close element (switching circuit)
12 Filter 121, 122 Coil 13 Across the line capacitor 15 Open / close element (switching circuit, short circuit)
16 Open / close element (short circuit)
20 Diode bridge (first rectifier circuit)
30 Harmonic suppression circuit 40 Main power supply unit 41 Smoothing capacitor 50 Auxiliary power supply unit 51 Smoothing capacitor 52 Diode (second rectifier circuit)

Claims (3)

In a power supply apparatus comprising a plurality of power supply units, having a first state in which an AC voltage is received and power is supplied to the load by each power supply unit, and a second state in which power is supplied by a part of the power supply unit ,
A first rectifier circuit for rectifying an alternating voltage;
A filter having a coil interposed in each electric circuit on the input side of the first rectifier circuit;
A short circuit that shorts one of the coils;
A switching circuit that switches between the first state and the second state by closing or opening one electric circuit on the input side of the filter;
A second rectifier circuit provided on the input side of the switching circuit,
The switching circuit is
In the first state, a current is supplied to each coil to supply a voltage rectified by the first rectifier circuit to each power supply unit. In the second state, the coil is short-circuited by the short circuit. A power supply apparatus configured to supply a voltage rectified by the rectifier circuit to a part of the power supply unit. The power supply unit is
The power is supplied to a plurality of loads in the first state, and the power is supplied to some of the plurality of loads in the second state. The power supply described. The second rectifier circuit includes:
The rectified voltage is supplied to a part of the power supply unit via a coil different from the coil short-circuited by the short-circuit in the second state. The power supply device according to claim 2.

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