JP4765662B2 - Inverter device - Google Patents

Description

  The present invention relates to an inverter device used for a washing machine, a washing / drying machine, an air conditioner, etc. used for business use or in a general household.

  Conventionally, this type of inverter device has been operated by converting an AC power source into a DC voltage using a voltage doubler rectifier circuit and inputting the DC voltage into the inverter circuit (see, for example, Patent Document 1).

  FIG. 6 shows a circuit diagram of an inverter device that operates as a conventional electric washing machine described in Patent Document 1, and is connected to a single-phase AC power source 1 from the rectifier circuit 2 and the rectifier circuit 2 to the DC. An inverter circuit 3 that operates by being supplied with a voltage, and an electric motor 4 that is driven by being supplied with AC power from the inverter circuit 3 are provided.

  The inverter circuit 3 controls the gate voltage of the six switching elements combining the IGBT and the diode according to the on / off signal input to the drive circuit 5, and the control circuit 6 sends the on / off signal to the drive circuit 5. Is generated.

  The rectifier circuit 2 includes a rectifier bridge 7 and a series circuit of capacitors 8 and 9 connected to the output of the rectifier bridge 7, and the rectifier bridge 7 is constituted by four diodes 10, 11, 12, and 13. It has become a thing.

With the above configuration, the conventional inverter device supplies the DC voltage VDC obtained by doubling the AC voltage input from the AC power source 1 to the inverter circuit 3, and rotates the motor 4 to perform operations such as washing and dehydration. It was something to do.
JP 2001-259281 A

  However, since the above-described conventional inverter device has double voltage rectification, the DC voltage VDC can be higher than the voltage of the AC power supply 1. There is an effect that the current rating of the switching element can be made small and inexpensive accordingly, but when the inverter circuit 3 having a large power is provided, the current when supplying power from the AC power source 1 is large. For example, when an electric power of about 1 kW is to be supplied from the AC power supply 1 having an effective value of 100 V, an effective value of current exceeding 10 A flows in a portion indicated by a thick line in FIG.

  According to the study by the inventors, when an electric current having an effective value exceeding 7 A is applied to a wiring (pattern) formed of a copper foil on a printed circuit board, the pattern surface in a state of no wind and mounted. The temperature rise due to heat generation in the lead wire soldered part of the component cannot be effectively suppressed, and the reliability tends to be lowered. In FIG. The current in the path where the connection point of the positive terminal is connected to the AC power supply 1 is a value exceeding 10 A, which is equal to the input current of the inverter device, and there is a problem of reliability when providing this pattern on the printed circuit board. It will have.

  The present invention solves the above-described conventional problems, and even when an inverter circuit that operates with a large power is used, a connection point between two capacitors 8 and 9 connected in series for performing double voltage rectification and an AC power source 1 are provided. An object of the present invention is to provide an inverter device capable of reducing the effective value of the current flowing through the wiring to be connected and ensuring high reliability.

  In order to solve the above-described conventional problems, an inverter device according to the present invention is supplied with an alternating current from a first capacitor and a second capacitor, a plurality of diodes, and a single-phase alternating current power source mounted on a printed circuit board. A voltage doubler having an input terminal, a first pattern connecting the input terminal and the negative side terminal of the first capacitor, and a second pattern connecting the input terminal and the positive side terminal of the second capacitor Type rectifier circuit and an inverter circuit that operates by being supplied with a DC voltage from the rectifier circuit. The effective value of the current to the printed circuit board pattern is calculated with respect to the input power (input power) to the inverter device. Therefore, a highly reliable inverter device can be realized.

  The inverter device of the present invention can ensure high reliability.

  The first invention includes a first capacitor and a second capacitor mounted on a printed circuit board, a plurality of diodes, an input terminal for receiving an alternating current from a single-phase alternating current power supply, the input terminal and the first capacitor A double voltage type rectifier circuit having a first pattern for connecting the negative side terminal of the capacitor, a second pattern for connecting the input terminal and the positive side terminal of the second capacitor, and a direct current from the rectifier circuit. By having an inverter circuit that operates by being supplied with a voltage, the effective value of the current to the pattern of the printed circuit board can be kept low relative to the input power (input power) to the inverter device. .

  The second invention is configured to have a first input terminal connected to the minus terminal of the first capacitor of the first invention and a second input terminal connected to the plus terminal of the second capacitor. Thus, the current passing through the two input terminals can be reliably suppressed.

  In addition to the second invention, a third invention has a reactor having a first winding and a second winding, the first winding is connected to a first input terminal, and the second winding By adopting a configuration in which the winding is connected to the second input terminal, it is possible to improve the power factor viewed from the AC power source and to suppress the value of the current flowing in the pattern.

  In addition to the second invention, the fourth invention has a first reactor and a second reactor, the first reactor is connected to a first input terminal, and the second reactor is a second reactor. By connecting to the input terminal, the current value passing through the reactor and each input terminal can be suppressed, and the reliability can be further increased while maintaining the power factor.

  A fifth invention is the first invention, wherein the first AC input terminal, the second AC input terminal, the positive DC output terminal, the negative DC output terminal, a rectifier bridge having four diodes, A third reactor having three windings and a fourth winding, and a fourth reactor having fifth and sixth windings, and the positive DC output terminal is connected to the first capacitor. Connected to the positive terminal, the negative DC output terminal is connected to the negative terminal of the second capacitor, the third winding is connected to the first AC input terminal, and the fourth winding is the By connecting to the positive terminal of the second capacitor, connecting the fifth winding to the second AC input terminal, and connecting the sixth winding to the negative terminal of the first capacitor, The power factor can be secured by two reactors and the noise can be reduced. Current passing through each input terminal and the AC input terminals, and becomes capable of suppressing current passing through each reactor.

  In the sixth aspect of the invention, the third reactor and the fourth reactor of the fifth aspect are mounted on the printed circuit board, so that the current value of each part is suppressed and sufficient reliability is ensured, and the printed circuit board is mounted. Therefore, the manufacturing cost can be reduced.

  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 shows a circuit diagram of an inverter device according to a first embodiment of the present invention. This embodiment shows an inverter device that operates as a drum-type washing machine with a drying function having a heat pump.

  In FIG. 1, an input terminal 22 that receives an alternating current from an alternating current power supply 21 that outputs a single-phase alternating voltage of 50 or 60 hertz with an effective value of 100 volts, a voltage doubler rectifier circuit 23, and a rectifier circuit 23, an inverter circuit 24 that operates by receiving a DC voltage VDC from the inverter 23, a drum rotating motor 25 that is driven by an AC current supplied from the inverter circuit 24, and a control that outputs an on / off signal of each switching element in the washing inverter circuit 24 A circuit 26 is provided.

  Further, in order to compress the refrigerant during drying, an inverter circuit 27 that receives the DC voltage VDC from the rectifier circuit 23, and an electric motor 28 that is driven to rotate by receiving an AC current from the inverter circuit 27 and compresses the refrigerant are connected. As for the inverter circuit 27, the internal switching elements are turned on and off by a signal from the control circuit 26 as necessary during drying.

  The drive circuits 29 and 30 adjust the gate voltages of the switching elements in the inverter circuits 24 and 27, respectively, with respect to the TTL level digital signal output from the control circuit 26, and perform an on / off operation.

  The rectifier circuit 23 includes a rectifier bridge 40. The rectifier bridge 40 includes a first AC input terminal 41, a second AC input terminal 42, a positive DC output terminal 43, a negative DC output terminal 44, and four Diodes 45, 46, 47, and 48.

  The rectifier circuit 23 further includes an electrolytic first capacitor 51 and a second capacitor 52. The positive side terminal of the first capacitor 51 is connected to the positive DC output terminal 43 and the negative side of the second capacitor 52. The terminal is connected to the negative DC output terminal 44.

  The input terminal 22 and the negative terminal of the first capacitor 51 are connected by a first pattern 55 made of copper foil, and the input terminal 22 and the positive terminal of the second capacitor 52 are similarly copper foil. Wiring is made by the second pattern 56 configured as described above.

  Further, in the present embodiment, the third capacitor 57 is connected between the plus DC output terminal 43 and the minus DC output terminal 44, and is configured to suppress the ripple voltage component of VDC.

  The printed circuit board 60 is mounted with the component electronic components of the rectifier circuit 23, the inverter circuits 24 and 27, and the control circuit 26.

  In the present embodiment, the printed circuit board 60 and the AC power supply 21 are connected via a single-winding reactor 63, a common mode choke coil 64, and a current fuse 65. .

  With the above configuration, the current that flows from the AC power supply 21 through the input terminal 22 is divided into a current that charges and discharges the first capacitor 51 and a current that charges and discharges the second capacitor 52. Pattern 55 and the latter flow into the second pattern 56, both of which fall within an effective current value of 7 A or less under the power consumption condition of 1 kW, and the first capacitor 51 mounted on the printed circuit board 60. The reliability of the copper foil portion to which the second capacitor 52 is connected can be sufficiently enhanced.

  In the present embodiment, the rectifier circuit 23 is connected to the third capacitor 57, so that the voltage ripple of the output voltage VDC can be effectively suppressed and the AC power supply 21 can be viewed. The power factor is easy to secure.

  In the present embodiment in which the third capacitor 57 is provided, in order to keep the power factor high, the capacitance of the first capacitor 51 and the second capacitor 52 is a relatively small value of about 200 to 400 microfarads. As the first capacitor 51 and the second capacitor 52, those having a specification with a large ripple-proof current against the capacitance are suitable.

  However, the provision of the third capacitor 57 is not necessarily required for realizing the present invention. For example, both the first capacitor 51 and the second capacitor 52 have a large capacity of 1000 microfarads or more. As such, the voltage ripple of the first capacitor 51 and the second capacitor 52 is sufficiently suppressed, and the third capacitor 57 may not be connected. In this case, the inductance value of the reactor 63 is set appropriately. For example, the power factor viewed from the AC power source 21 can be sufficiently increased, and these can be freely designed.

(Embodiment 2)
FIG. 2 shows a circuit diagram of an inverter device according to the second embodiment of the present invention.

  In the present embodiment, the reactor 70 has a first winding 71 and a second winding 72, and the first winding 71 is connected to the first input terminal 75, and the second winding 71. The winding 72 is connected to the second input terminal 76.

  The negative terminal of the first capacitor 51 is connected to the first input terminal 75 through the copper foil of the printed circuit board 60, and the positive terminal of the second capacitor 52 is connected to the second input terminal 76, respectively. It has been configured.

  In the present embodiment, the two AC input terminals 41 and 42 of the rectifier bridge 40 are separately connected to the common input terminal 77 by the third pattern 78 and the fourth pattern 79, respectively.

  A reverse voltage protection diode 81 is provided for the first capacitor 51, a reverse voltage protection diode 82 is provided for the second capacitor 52, a cathode is provided on the positive electrode side of the capacitor, and a capacitor is provided. Are connected in parallel with the polarity of the anode coming to the negative electrode side, and when the power source is turned on, a transient reverse voltage is applied to the electrolytic capacitors 51 and 52 at the moment of conduction, and the reverse voltage Sufficient reliability is ensured by performing the action of blocking the application of.

  On the other hand, under normal steady-state operating conditions, the capacitors 51 and 52 are both subjected to voltage application in the correct direction. Therefore, the reverse voltage protection diodes 81 and 82 are both in the reverse blocking state and the current flows. There is no flow.

  Therefore, it is not necessary to connect to a heatsink or the like, and an extremely inexpensive lead wire axial type can be used as a reverse voltage protection diode.

  As for the rectifier bridge 40, the one attached to the radiator is used, and the inverter circuits 24, 27 having large power consumption are connected while effectively using the four diodes 45, 46, 47, 48. The current that has been shared and whose effective value is suppressed is passed to the two AC input terminals 41 and 42, and the current passes through the third pattern 78 and the fourth pattern 79 from the common input terminal 77. Therefore, in the present embodiment, the third pattern 78 and the fourth pattern 79 are both made of copper foil in the printed circuit board 60, and the current passing through them is 7A or less. Thus, the operation can be performed while ensuring sufficiently high reliability while satisfying the standard.

  FIG. 3 shows the pin arrangement of the rectifying bridge 40 of the inverter device according to the present embodiment. At the same time, the portion below the broken line P shows the pattern of the printed circuit board.

  As shown in FIG. 3, the four diodes 45, 46, 47, and 48 are encapsulated in one resin package and can be attached to an aluminum heat sink (heat sink). I used what was.

  The four terminals arranged in a line have a shape in which two AC input terminals 41 and 42 to which AC is input are sandwiched between a plus DC output terminal 43 and a minus DC output terminal 44. .

  When the rectifier bridge 40 having such a pin arrangement is used, the AC input terminals 41 and 42 are the two inner terminals of the four, so that it is difficult to ensure the pattern width. Therefore, it is necessary to design to secure the pattern interval for insulation. Therefore, according to the test by the inventors, when the operation is continued in a state where the current effective value of one terminal exceeds 7 A again. In particular, when there is no air for cooling, the temperature rise in the vicinity of the soldered portion 85 becomes large, which makes it difficult to ensure reliability.

  In the present embodiment, as shown in FIG. 3, the rectifier bridge 40 is mounted on the printed circuit board 60, and the third pattern 78 from the AC input terminal 41 of the rectifier bridge 40 and the AC input terminal 42. The fourth pattern 79 is provided separately from the positive DC output terminal 43 and the negative DC output terminal 44 from the soldering portion 85, respectively, as in the patterns 86 and 87. Wiring with foil is made.

  Furthermore, in the present embodiment, a common input terminal 77 is provided using a connector at a portion where the third pattern 78 and the second pattern 79 are connected, and an AC current from the AC power source 21 is provided. Supply can be received.

  Also in this embodiment, in order to prevent the noise from the inverter circuits 24 and 27 from flowing back to the AC power source 21, wiring is connected to the AC power source 21 in the form in which the common mode choke coil 64 is used on the way. It will be what has been made.

  In the present embodiment, because the weight of the reactor 70 is large and the heat generation is large, the reactor 70 is not mounted on the printed circuit board 60 but attached to another place.

  However, with respect to the current plane, the magnitude of the current passing through the windings 71 and 72 can be 7 A or less, and therefore it is sufficiently possible to adopt a configuration for mounting on the printed circuit board 60.

  Since such a reactor 70 has a sufficient inductance, the power factor viewed from the AC power source 21 is improved to about 85%, and therefore even with the same input power, Accordingly, the effective value and peak value of the input current from the AC power source 21 can be reduced, and the burden on the AC power source 21 can be reduced.

  In the present embodiment, the effective value of the current input from the AC power supply 21 is suppressed by the power factor improvement effect by the reactor 70, and the current sharing to the third pattern 78 and the fourth pattern 79 is also performed. As a result, the current value in this portion can be suppressed, and the reliability can be further increased.

  In addition, each of the diodes 45 and 46 can perform a rectifying operation with a smaller current than in the case of the prior art, and operates reasonably.

  Similarly, the diodes 47 and 48 are connected in parallel and share current.

(Embodiment 3)
FIG. 4 shows a circuit diagram of an inverter device according to the third embodiment of the present invention.

  In FIG. 4, the portion of the circuit that is connected to the output of the rectifier circuit 23 and receives the DC voltage VDC is not shown in the circuit diagram, but the equivalent circuit shown in the first embodiment is connected. It is a composition.

  In the present embodiment, the first input terminal 90 connected to the negative terminal of the first capacitor 51 and the second input connected to the positive terminal of the second capacitor 52 mounted on the printed circuit board 60. There are terminals 91, which are electrically connected by copper foil.

  In addition, a first reactor 93 and a second reactor 94 are provided. One end of the first reactor 93 is connected to the first input terminal 90, and one end of the second reactor 94 is connected to the second reactor 94. The other end of the first reactor 93 and the second reactor 94 is connected to the input terminal 91 and is connected to the AC power source 21 via the common mode choke coil 64.

  With the above configuration, in the inverter device of the present embodiment, the current value passing through the first input terminal 90 and the second input terminal 91 is the input current input from the AC power supply 21 as in the first embodiment. Therefore, the current value in the portion mounted on the printed circuit board 60 is reduced to 7 A or less, so that sufficient reliability can be secured, and the first reactor 93 and the second reactor 94 are secured. Since the upper limit of the flowing current can be realized, it can be designed with a small current specification, and can be made small and light, so that it can be mounted on the printed circuit board 60. You can go.

  In the present embodiment also, the third capacitor 57 is connected for the purpose of stabilizing the output DC voltage VDC, but the sum of the inductances of the first reactor 93 and the second reactor 94 is the first. Since it exists between the input terminal 90 and the 2nd input terminal 91, the 3rd capacitor | condenser 57 acts effectively with respect to stabilization of VDC.

(Embodiment 4)
FIG. 5 shows a circuit diagram of an inverter device according to the fourth embodiment of the present invention.

  Also in FIG. 5, the circuit portion that is connected to the output of the rectifier circuit 23 and receives the DC voltage VDC is not shown in the circuit diagram, but an equivalent one shown in the first embodiment is connected. It is a composition.

  In the present embodiment, the rectifier circuit 23 is such that the third reactor 100 has a third winding 101 and a fourth winding 102 wound around a core of a silicon steel plate with a gap. The fourth reactor 110 has a fifth winding 111 and a sixth winding 112 wound around a core of a silicon steel plate with a gap, and the third reactor 100 and the fourth reactor 110 are Are also mounted on the printed circuit board 60.

  The rectifier bridge 40 includes a first AC input terminal 41, a second AC input terminal 42, a positive DC output terminal 43, a negative DC output terminal 44, and four diodes 45, 46, 47, and 48. Yes, this is also equivalent to the first embodiment.

  The positive DC output terminal 43 is connected to the positive terminal of the first capacitor 51, and the negative DC output terminal 44 is connected to the negative terminal of the second capacitor 52.

  One end of the third winding 101 is connected to the first AC input terminal 41, the fourth winding 102 is connected to the plus terminal of the second capacitor 52, and the fifth winding 111 is the second winding. Connected to the AC input terminal 42, the sixth winding 112 is connected to the negative terminal of the first capacitor 51.

  Note that the terminals of the third winding 101 and the fifth winding 111 that are not described above are connected to the common input terminal 115 provided on the printed circuit board 60, and the fourth winding 102, the fourth winding 111, and the like. The other terminal of the sixth winding 112 is connected to the input terminal 115 provided on the printed circuit board 60, and both the common input terminal 115 and the input terminal 116 are connected to the common mode choke coil 64. , And the current fuse 65 to the AC power source 21.

  Also in the present embodiment, the power factor when the inverter device is viewed from the AC power source 21 can be relatively easily secured by the action of the normal mode inductance of the third reactor 100 and the fourth reactor 110. At the same time, there is also an action such as a leakage inductance of the third reactor 100 and the fourth reactor 110, and a component in which electrical noise from the inverter circuits 24 and 27 flows back to the AC power source 21 (noise terminal voltage or the like). Can be suppressed relatively easily.

  Further, as described in the first embodiment, the current ratings of the third reactor 100 and the fourth reactor 110 are close to the currents of the first capacitor 51 and the second capacitor 52, and the sharing is determined. Therefore, design such as current superposition characteristics and current rating of the winding can be easily performed.

  The current passing through the third winding 101 and the fifth winding 111 is shared by the diodes 45 and 47 and shared by the diodes 46 and 48. The impedance of the wiring pattern to the input terminal 115 is raised as a factor of fluctuation of the current sharing ratio. In the present embodiment, the third winding 101 and the fourth winding 102, and the fifth winding are used. Since 111 and the sixth winding 112 are magnetically coupled, there is an effect that an electromotive force is generated in each winding in a direction to suppress current imbalance, and it is easy to achieve a good current balance. .

  In each of the above embodiments, the inverter device is a washing machine with a drying function and uses two inverter circuits 23 and 27. However, the inverter device is not particularly limited to such an inverter device. , For example, one that drives a compressor of an air conditioner, one that has an inverter circuit for induction heating, or one that uses an inverter circuit that outputs power such as direct current, alternating current, and high frequency as a power converter In addition, various inverter circuits can be used.

  As described above, the inverter device according to the present invention provides reliability by flowing the input current to the connection point between the first capacitor and the second capacitor, which performs voltage doubler rectification, in two paths. And can be widely applied to various inverter devices.

The circuit diagram of the inverter apparatus in Embodiment 1 of this invention The circuit diagram of the inverter apparatus in Embodiment 2 of this invention Pin arrangement and pattern diagram for rectifier bridge mounting of the inverter device The circuit diagram of the rectifier circuit of the inverter apparatus in Embodiment 3 of this invention The circuit diagram of the rectifier circuit of the inverter apparatus in Embodiment 4 of this invention Circuit diagram of inverter device in the prior art

Explanation of symbols

21 AC power source 22 Input terminal 23 Rectifier circuit 24, 27 Inverter circuit 40 Rectifier bridge 41 First AC input terminal 42 Second AC input terminal 43 Positive DC output terminal 44 Negative DC output terminal 45, 46, 47, 48 Diode 51 First capacitor 52 Second capacitor 55 First pattern 56 Second pattern 60 Printed circuit board 70 Reactor 71 First winding 72 Second winding 75, 90 First input terminal 76, 91 Second Input terminal 93 1st reactor 94 2nd reactor 100 3rd reactor 101 3rd winding 102 4th winding 110 4th reactor 111 5th winding 112 6th winding

Claims (6)

A first capacitor and a second capacitor mounted on a printed circuit board; a plurality of diodes; an input terminal receiving an alternating current from a single-phase alternating current power supply; the input terminal; and a negative terminal of the first capacitor And a voltage doubler type rectifier circuit having a second pattern for connecting the input terminal and the positive terminal of the second capacitor, and a DC voltage supplied from the rectifier circuit to operate. An inverter device having an inverter circuit. The inverter apparatus according to claim 1, further comprising: a first input terminal connected to a negative terminal of the first capacitor; and a second input terminal connected to a positive terminal of the second capacitor. A reactor having a first winding and a second winding, wherein the first winding is connected to a first input terminal and the second winding is connected to a second input terminal. Item 3. The inverter device according to Item 2. The inverter apparatus according to claim 2, further comprising a first reactor and a second reactor, wherein the first reactor is connected to a first input terminal, and the second reactor is connected to a second input terminal. A first AC input terminal, a second AC input terminal, a positive DC output terminal, a negative DC output terminal, a rectifier bridge having four diodes, a third winding and a fourth winding having a fourth winding; 3 reactor, a fourth reactor having a fifth winding and a sixth winding, the positive DC output terminal is connected to the positive terminal of the first capacitor, and the negative DC output terminal is connected to the positive DC output terminal. Connected to the negative terminal of a second capacitor, the third winding is connected to the first AC input terminal, the fourth winding is connected to the positive terminal of the second capacitor, and 5. The inverter device according to claim 1, wherein a fifth winding is connected to the second AC input terminal, and a sixth winding is connected to a negative terminal of the first capacitor. The inverter device according to claim 5, wherein the third reactor and the fourth reactor are mounted on a printed circuit board.