Printed circuit board, electric circuit, power conversion device, and air conditioner

Abstract

This printed circuit board includes: a base material formed of an insulator; and a pattern which is formed on the base material and on which a DC voltage unit connected to a rectifier and an inverter is to be mounted in a power conversion device. The pattern is configured to have implemented thereon a first setting comprising a plurality of first electrolytic capacitors as the DC voltage unit, or a second setting comprising a second electrolytic capacitor and a low-capacitance capacitor having a capacitance lower than that of the plurality of first electrolytic capacitors and also lower than that of the second electrolytic capacitor.

Description

Printed circuit board, electric circuit, power conversion device, and air conditioner

[0001] The present disclosure relates to a printed circuit board, an electric circuit, a power conversion device, and an air conditioner, and more particularly to a printed circuit board for a power conversion device, and an electric circuit, a power conversion device, and an air conditioner that use the printed circuit board.

[0002] In a power conversion device, a chemical capacitor-less inverter has been developed in which the electrolytic capacitor for smoothing the voltage of the main circuit is replaced with a film capacitor having a smaller capacitance than the electrolytic capacitor. Patent Document 1 proposes a power supply circuit using a small-capacity capacitor with a capacitance of, for example, several tens of μF or less as such a capacitor. The use of a small-capacity film capacitor can reduce the cost of the power conversion device.

[0003] JP 2012-178974 A

[0004] However, it is not possible to replace all electrolytic capacitors used in power conversion devices with film capacitors. The choice of whether to use an electrolytic capacitor board using electrolytic capacitors or a chemical-capacitor-less board using film capacitors in a power conversion device depends on the priorities of the user's requirements or the standards of each country. For example, an electrolytic capacitor board is used when the destination of the air conditioner equipped with the power conversion device places the highest priority on reducing noise caused by vibration or when strict harmonic standards are in place. Furthermore, a chemical-capacitor-less board is used when low cost is the highest priority and the destination's regulations are met. In this case, printed circuit boards and other components must be prepared separately for the electrolytic capacitor board and the chemical-capacitor-less board, which increases the cost of the air conditioner.

[0005] An object of the present disclosure is to provide a printed circuit board, an electric circuit, a power conversion device, and an air conditioner that can meet user demands.

[0006] The printed circuit board according to the present disclosure includes a base material made of an insulator and a pattern formed on the base material on which a DC voltage section connected to a rectifier and an inverter in a power conversion device is mounted, and the pattern is configured to mount either a first setting including a plurality of first electrolytic capacitors as the DC voltage section, or a second setting including a second electrolytic capacitor and a small-capacity capacitor having a smaller capacity than the plurality of first electrolytic capacitors and also having a smaller capacity than the second electrolytic capacitor.

[0007] In addition, the electric circuit according to the present disclosure includes the above-mentioned printed circuit board and the DC voltage unit mounted on the printed circuit board, and is configured such that in the first setting, the plurality of first electrolytic capacitors are used to smooth the voltage of the power conversion device, and in the second setting, the second electrolytic capacitors are used to suppress voltage fluctuations in the power conversion device.

[0008] In addition, the power conversion device according to the present disclosure includes the above-mentioned printed circuit board and the DC voltage unit mounted on the printed circuit board, and the DC voltage unit is composed of the plurality of first electrolytic capacitors, or the second electrolytic capacitor and the small-capacity capacitor.

[0009] An air conditioner according to the present disclosure includes the power conversion device provided with the above-described printed circuit board, and a compressor equipped with the power conversion device.

[0010] According to the printed circuit board, electric circuit, power converter, and air conditioner disclosed herein, by mounting either an electrolytic capacitor or a small-capacity capacitor in the DC voltage section, it is possible to switch between an electrolytic capacitor board and a chemical capacitor-less board, and therefore it is possible to provide one of two types of power converters from a single type of printed circuit board in response to user requests.

[0011] FIG. 1 is a circuit diagram of an electric circuit when the power conversion device according to embodiment 1 has an electrolytic capacitor substrate. FIG. 2 is a circuit diagram of an electric circuit when the power conversion device according to embodiment 1 has a chemical-capacitor-less substrate. FIG. 3 is a schematic diagram of the front surface of a printed circuit board according to embodiment 1. FIG. 4 is a schematic diagram of the back surface of a printed circuit board according to embodiment 1. FIG. 5 is an image diagram of implementation when the printed circuit board according to embodiment 1 is used as an electrolytic capacitor substrate. FIG. 6 is an image diagram of implementation when the printed circuit board according to embodiment 1 is used as a chemical-capacitor-less substrate. FIG. 7 is a circuit diagram realized by a pattern formed on the printed circuit board according to embodiment 1. FIG. 8 is a schematic diagram showing an air conditioner according to embodiment 2.

[0012] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that the present disclosure is not limited to the embodiments described below. Furthermore, in the following drawings, including FIG. 1, the size relationships of the components may differ from the actual ones. Furthermore, in the following description, terms indicating directions are used as appropriate to facilitate understanding of the present disclosure, but these terms are used only to explain the present disclosure and do not limit the present disclosure. Examples of terms indicating directions include "up," "down," "right," "left," "front," and "rear."

[0013] First Embodiment In the first embodiment, by switching the mounting, it is possible to obtain a power conversion device 100 having an electrolytic capacitor substrate and a power conversion device 100 having a chemical capacitor-less substrate, i.e., a chemical capacitor-less inverter.

[0014] Fig. 1 is a circuit diagram of an electric circuit 10 in a case where a power conversion device 100 according to a first embodiment has an electrolytic capacitor substrate. As shown in Fig. 1, an AC power supply 1 and an electric motor 2 are connected to the power conversion device 100. The power conversion device 100 converts the power of the AC power supply 1 to an arbitrary frequency and an arbitrary voltage and supplies the power to a load such as the electric motor 2. The AC power supply 1 is, for example, a three-phase AC voltage of 200V.

[0015] The power conversion device 100 includes a rectifier circuit 3, a busbar circuit 4, and an inverter circuit 5. The rectifier circuit 3, the busbar circuit 4, and the inverter circuit 5 form an electric circuit 10. The busbar circuit 4 is an example of a DC voltage section. The electric circuit 10 also includes a reactor 6.

[0016] The rectifier circuit 3 rectifies the AC voltage input from the AC power supply 1, converts it into a DC voltage, and outputs it from a first output terminal 3a and a second output terminal 3b. The rectifier circuit 3 is, for example, a three-phase full-wave rectifier having a bridge circuit formed by six diodes. The first output terminal 3a of the rectifier circuit 3 is connected to a positive bus 11. The second output terminal 3b of the rectifier circuit 3 is connected to a negative bus 12. The DC voltage rectified by the rectifier circuit 3 contains low-order harmonic components pulsating at a frequency six times the voltage frequency of the AC power supply 1.

[0017] The inverter circuit 5 converts the DC voltage rectified by the rectifier circuit 3 into an AC voltage in accordance with a drive switch signal and outputs the AC voltage to the electric motor 2. The DC voltage is input from a first input terminal 5a and a second input terminal 5b of the inverter circuit 5. The first input terminal 5a of the inverter circuit 5 is connected to a positive bus 11. The second input terminal 5b of the inverter circuit 5 is connected to a negative bus 12. In other words, the positive bus 11 connects the first output terminal 3a of the rectifier circuit 3 to the first input terminal 5a of the inverter circuit 5. Furthermore, the negative bus 12 connects the second output terminal 3b of the rectifier circuit 3 to the second input terminal 5b of the inverter circuit 5.

[0018] The inverter circuit 5 is configured with a plurality of switching elements (not shown). The operation of the inverter circuit 5 is controlled by an inverter control means (not shown). The inverter circuit 5 supplies AC current of a predetermined frequency to the electric motor 2.

[0019] The busbar circuit 4 is connected between the rectifier circuit 3 and the inverter circuit 5. When the power conversion device 100 has an electrolytic capacitor board, the busbar circuit 4 is configured with an electrolytic capacitor 41. The electrolytic capacitor 41 is provided to smooth the waveform of low-order harmonic components of the DC voltage rectified by the rectifier circuit 3.

[0020] The electrolytic capacitor 41 is a capacitor that uses an oxide film of aluminum, tantalum, or the like as a dielectric. One end of the electrolytic capacitor 41 is connected to the positive bus 11 that connects the first output terminal 3a of the rectifier circuit 3 and the first input terminal 5a of the inverter circuit 5. The other end of the electrolytic capacitor 41 is connected to the negative bus 12 that connects the second output terminal 3b of the rectifier circuit 3 and the second input terminal 5b of the inverter circuit 5. The electrolytic capacitor 41 has a capacitance large enough to smooth the low-order harmonic component waveform of the DC voltage.

[0021] The reactor 6 is connected to the first output terminal 3a of the rectifier circuit 3 by the positive bus 11. An electrolytic capacitor 41 constituting the busbar circuit 4 is connected downstream of the reactor 6. The reactor 6 has the effect of reducing power supply harmonics. While FIG. 1 shows an example in which the reactor 6 is connected between the rectifier circuit 3 and the busbar circuit 4, the reactor 6 may also be connected between the AC power supply 1 and the rectifier circuit 3.

[0022] 2 is a circuit diagram of the electric circuit 10 when the power conversion device 100 according to the first embodiment has a chemical capacitor-less board. As shown in FIG. 2, when the power conversion device 100 has a chemical capacitor-less board, the busbar circuit 4 is composed of a small-capacity capacitor 42, a diode 43, an electrolytic capacitor 41, and a resistor 44. The small-capacity capacitor 42 is provided to suppress voltage fluctuations in the power conversion device 100.

[0023] The small-capacity capacitor 42 is a capacitor having a smaller capacitance than the electrolytic capacitor 41. The small-capacity capacitor 42 is, for example, a film capacitor. A film capacitor is a capacitor that uses, for example, polypropylene, polyethylene terephthalate, polyphenylene sulfide, or polyethylene naphthalate as a dielectric.

[0024] One end of the small-capacity capacitor 42 is connected to the positive bus 11 that connects the first output terminal 3 a of the rectifier circuit 3 and the first input terminal 5 a of the inverter circuit 5. The other end of the small-capacity capacitor 42 is connected to the negative bus 12 that connects the second output terminal 3 b of the rectifier circuit 3 and the second input terminal 5 b of the inverter circuit 5.

[0025] The electrolytic capacitor 41 is connected in series with a diode 43 connected to the positive bus 11 so that the high-potential side serves as the anode. Specifically, one end of the electrolytic capacitor 41 is connected to the cathode of the diode 43, and the other end is connected to the negative bus 12 that connects the second output terminal 3 b of the rectifier circuit 3 and the second input terminal 5 b of the inverter circuit 5.

[0026] The electrolytic capacitor 41 is connected in parallel to the resistor 44. Specifically, one end of the electrolytic capacitor 41 is connected to the cathode side of the diode 43, and the other end is connected in parallel to the resistor 44, which is connected to the negative bus 12 that connects the second output terminal 3 b of the rectifier circuit 3 and the second input terminal 5 b of the inverter circuit 5.

[0027] Here, the small-capacity capacitor 42 does not smooth the low-order harmonic component waveform of the DC voltage, and therefore cannot absorb voltage fluctuations when the operation of the AC power supply 1 or the electric motor 2 changes. On the other hand, the electrolytic capacitor 41 does not smooth the DC voltage because of the diode 43, but it can prevent sudden changes in the bus voltage. The charge accumulated in the electrolytic capacitor 41 is discharged by a resistor 44 connected in parallel with the electrolytic capacitor 41. The provision of the electrolytic capacitor 41 prevents the elements constituting the power conversion device 100 from being destroyed by sudden changes in the bus voltage.

[0028] When the power conversion device 100 has a chemical capacitor-less board, the reactor 6 may have a smaller capacity than that used when the power conversion device 100 has an electrolytic capacitor board. This is because when the power conversion device 100 has a chemical capacitor-less board, that is, in the case of a chemical capacitor-less inverter, the amount of low-order harmonics generated in the power supply voltage is smaller than in a power conversion device 100 having an electrolytic capacitor 41.

[0029] FIG. 2 shows an example in which the reactor 6 is connected between the rectifier circuit 3 and the busbar circuit 4, but similar to the case of FIG. 1 , the reactor 6 may be connected between the AC power supply 1 and the rectifier circuit 3.

[0030] Fig. 3 is a schematic diagram of the front surface of the printed circuit board 111 according to embodiment 1. Fig. 4 is a schematic diagram of the back surface of the printed circuit board 111 according to embodiment 1. In Fig. 3 and Fig. 4, dotted lines indicate the positions of electronic components mounted on the printed circuit board 111. For ease of explanation, Fig. 3 and Fig. 4 show the electronic components mounted on the electrolytic capacitor board and the electronic components mounted on the chemical capacitor-less board as if they were misaligned.

[0031] 3 and 4 , the printed circuit board 111 has a substrate 110, a plurality of holes 120, and a pattern 240. The plurality of holes 120 and the pattern 240 are an example of a circuit formed on the substrate 110. The plurality of holes 120 and the pattern 240 are configured to mount a busbar circuit 4 connected to the rectifier circuit 3 and the inverter circuit 5 of the power conversion device 100. In the power conversion device 100, the printed circuit board 111 can constitute either an electrolytic capacitor substrate or a chemical capacitor-less substrate. Note that the plurality of holes 120 and the pattern 240 may also be configured to mount the rectifier circuit 3 and the inverter circuit 5.

[0032] The substrate 110 is a substrate made of an insulating material, such as a glass epoxy substrate made of woven glass fiber and impregnated with epoxy resin. The multiple holes 120 are openings through which leads of electronic components such as the electrolytic capacitor 41 are inserted. The multiple holes 120 include a first hole 120a and a second hole 120b. Copper foil is applied to the substrate 110 inside and around the openings of the multiple holes 120. The leads of the electronic components are inserted into the openings of the multiple holes 120 and soldered, thereby mounting the electronic components on the substrate 110.

[0033] The pattern 240 is copper foil applied to the substrate 110 along a path along which electricity flows. The pattern 240 is configured so that electronic components mounted on the substrate 110 are inserted through the openings of the multiple holes 120 and conduct electricity as designed. The pattern 240 applied to the surface of the substrate 110 is wiring that becomes the positive bus 11 in the electric circuit 10 of FIGS. 1 and 2. The pattern 240 applied to the back surface of the substrate 110 is wiring that becomes the negative bus 12 in the electric circuit 10 of FIGS. 1 and 2, and is ground wiring. The pattern 240 is formed, for example, by a subtractive method, in which copper foil that previously covered the entire surface of the substrate 110 is removed and the wiring portion is left. The pattern 240 may also be formed by an additive method, in which a copper foil wiring pattern is added to the surface of the substrate 110. The pattern 240 connects the multiple holes 120 in parallel.

[0034] In addition, when electronic components are mounted on the surface of the substrate 110, the circuit may be formed not inside or around the plurality of open holes 120, but by copper foil applied to the shape of a pad, such as a rectangular shape.

[0035] 5 is a conceptual diagram illustrating the mounting of the printed circuit board 111 according to the first embodiment when it is used as an electrolytic capacitor board. The case where the printed circuit board 111 is used as an electrolytic capacitor board is an example of the first setting. As shown in FIG. 5 , when the printed circuit board 111 is used as an electrolytic capacitor board, an electrolytic capacitor 41 that constitutes the busbar circuit 4 in FIG. 1 is mounted on the printed circuit board 111. The electrolytic capacitor 41 is mounted in a plurality of holes 120 and a pattern 240 of the printed circuit board 111. The electrolytic capacitor 41 is electrically connected to the rectifier circuit 3 and the inverter circuit 5 via the plurality of holes 120 and the pattern 240 of the printed circuit board 111.

[0036] The electrolytic capacitor 41 includes, for example, a first electrolytic capacitor 41a and a plurality of third electrolytic capacitors 41b to 41g. The electrolytic capacitor 41 is an example of a plurality of first electrolytic capacitors, and the first electrolytic capacitor 41a is an example of a single first electrolytic capacitor. The first electrolytic capacitor 41a is mounted by soldering to a first hole 120a of the printed circuit board 111 shown in FIG. 3. The plurality of third electrolytic capacitors 41b to 41g are mounted by soldering to a plurality of second holes 120b of the printed circuit board 111 shown in FIG. 3.

[0037] As described above, the plurality of holes 120 of the printed circuit board 111 are connected in parallel by the pattern 240. Therefore, when the printed circuit board 111 is used as an electrolytic capacitor board, the first electrolytic capacitor 41a and the plurality of third electrolytic capacitors 41b to 41g are connected in parallel. By connecting the first electrolytic capacitor 41a and the plurality of third electrolytic capacitors 41b to 41g in parallel, the capacitance and withstand voltage of the power conversion device 100 are ensured.

[0038] 6 is a conceptual diagram of a printed circuit board 111 according to the first embodiment when used as a chemical capacitor-less board. The case where the printed circuit board 111 is used as a chemical capacitor-less board is an example of the second setting. As shown in FIG. 6 , when the printed circuit board 111 is used as a chemical capacitor-less board, a small-capacity capacitor 42 that constitutes the busbar circuit 4 of FIG. 2 is mounted on the printed circuit board 111. The small-capacity capacitor 42 is mounted in a plurality of holes 120 and a pattern 240 of the printed circuit board 111. The small-capacity capacitor 42 is electrically connected to the rectifier circuit 3 and the inverter circuit 5 via the plurality of holes 120 and the pattern 240 of the printed circuit board 111.

[0039] The small-capacity capacitor 42 includes, for example, a plurality of small-capacity capacitors 42a to 42c. The plurality of small-capacity capacitors 42a to 42c are mounted by soldering to the second holes 120b of the printed circuit board 111 shown in FIG. 3. The second holes 120b of the printed circuit board 111 are the positions where the third electrolytic capacitors 41b to 41g are mounted when the printed circuit board 111 is used as an electrolytic capacitor board. As described above, in the printed circuit board 111, the plurality of holes 120 are each connected in parallel by the pattern 240. Therefore, the plurality of small-capacity capacitors 42a to 42c are each mounted in parallel.

[0040] When the printed circuit board 111 is used as a chemical-capacitor-less board, a second electrolytic capacitor 41a is also mounted on the printed circuit board 111. The second electrolytic capacitor 41a used when the printed circuit board 111 is used as a chemical-capacitor-less board is the same as the first electrolytic capacitor 41a used when the printed circuit board 111 is used as an electrolytic capacitor board. The second electrolytic capacitor 41a is mounted in the same position as when the printed circuit board 111 is used as an electrolytic capacitor board. In other words, even when the printed circuit board 111 is used as a chemical-capacitor-less board, the second electrolytic capacitor 41a is soldered to the first hole 120a of the printed circuit board 111 shown in FIG. 3. When the printed circuit board 111 is used as a chemical-capacitor-less board, the diode 43 and resistor 44 that constitute the busbar circuit 4 of FIG. 2 are also mounted on the printed circuit board 111.

[0041] 7 is a circuit diagram realized by a pattern 240 formed on the printed circuit board 111 according to embodiment 1. As shown in FIG. 7, the pattern 240 includes a first pattern 240a, a second pattern 240b, a third pattern 240c, a fourth pattern 240d, and a fifth pattern 240e.

[0042] The first pattern 240a is a pattern 240 on which the first electrolytic capacitor 41a or the second electrolytic capacitor 41a is mounted. A first hole 120a is provided in the first pattern 240a. The second pattern 240b is a pattern 240 on which a plurality of third electrolytic capacitors 41b to 41g or a plurality of small-capacity capacitors 42a to 42c are mounted. A second hole 120b is provided in the second pattern 240b. The second pattern 240b is arranged in parallel to the first pattern 240a between the positive bus 11 and the negative bus 12.

[0043] The third pattern 240c and the fourth pattern 240d are arranged in series with the first pattern 240a. The third pattern 240c and the fourth pattern 240d are arranged in parallel with each other. The fifth pattern 240e is arranged in parallel with the first pattern 240a. A plurality of resistors 44 are connected in parallel to the fifth pattern 240e.

[0044] When the printed circuit board 111 is used as an electrolytic capacitor board, a first electrolytic capacitor 41a is mounted on the first pattern 240a, and multiple third electrolytic capacitors 41b-41g are mounted on the second pattern 240b. A jumper 45, which serves as a short-circuiting means, is mounted on the third pattern 240c, and nothing is mounted on the fourth pattern 240d, so that only the fourth pattern 240d is conductive. For example, two jumpers 45 are connected in parallel. The number of jumpers 45 is not particularly limited as long as it satisfies the current capacity value. Furthermore, for example, five resistors 44 are mounted on the fifth pattern 240e. The resistors 44 are provided to discharge the electric charge accumulated in the first electrolytic capacitor 41a and the multiple third electrolytic capacitors 41b-41g. This results in an electrolytic capacitor board.

[0045] When the printed circuit board 111 is used as a chemical capacitor-less board, a second electrolytic capacitor 41a is mounted on the first pattern 240a, and multiple small-capacity capacitors 42a-42c are mounted on the second pattern 240b. Furthermore, nothing is mounted on the third pattern 240c, and a diode 43 is mounted on the fourth pattern 240d, so that only the fourth pattern 240d is conductive. Furthermore, two resistors 44, for example, are mounted on the fifth pattern 240e. Because a chemical capacitor-less board does not have multiple third electrolytic capacitors 41b-41g like an electrolytic capacitor board, the number of resistors 44 can be reduced. This allows for a chemical capacitor-less board.

[0046] In this way, by mounting the small-capacity capacitor 42, the printed circuit board 111 can be used as a chemical-capacitor-less board, thereby making it possible to obtain an inexpensive power conversion device 100. The chemical-capacitor-less board also has the second electrolytic capacitor 41a mounted thereon as a regeneration countermeasure circuit, which can absorb voltage fluctuations that occur when the operation of the AC power supply 1 or the electric motor 2 changes, thereby protecting the power conversion device 100 from overvoltage. The chemical-capacitor-less board also has the diode 43 and resistor 44 mounted thereon, which allows the charge accumulated in the second electrolytic capacitor 41a to be discharged.

[0047] The printed circuit board 111 according to the first embodiment described above allows the busbar circuit 4 to be implemented by switching between a first setting including an electrolytic capacitor 41 and a second setting including a small-capacity capacitor 42. This allows the printed circuit board 111 to be switched between an electrolytic capacitor board including an electrolytic capacitor 41 and a chemical-capacitor-less board including a small-capacity capacitor 42, thereby providing both an electrolytic capacitor board and a chemical-capacitor-less board. Although a chemical-capacitor-less board is weaker in the regenerative operation of the motor 2 than an electrolytic capacitor board, the use of the printed circuit board 111 allows the circuitry of the electrolytic capacitor board to be reused to provide a chemical-capacitor-less inverter equipped with a film capacitor and a regenerative countermeasure circuit. Therefore, two types of power conversion devices 100 can be provided using a single type of printed circuit board 111: a power conversion device 100 including an electrolytic capacitor board and a power conversion device 100 including a chemical-capacitor-less board. The printed circuit board 111 can realize either a power conversion device 100 using an electrolytic capacitor 41 or a power conversion device 100 using a small-capacity capacitor 42, thereby meeting user demands at low cost.

[0048] Furthermore, the first hole 120a provided in the first pattern 240a of the printed circuit board 111 is used to mount either the first electrolytic capacitor 41a or the second electrolytic capacitor 41a of the electrolytic capacitors 41. The second hole 120b provided in the second pattern 240b is used to mount either the third electrolytic capacitors 41b to 41g or the small-capacity capacitor 42. When the printed circuit board 111 is used as an electrolytic capacitor board, the first electrolytic capacitor 41a is mounted in the first hole 120a provided in the first pattern 240a. The third electrolytic capacitors 41b to 41g are mounted in the second hole 120b provided in the second pattern 240b. When the printed circuit board 111 is used as a chemical capacitor-less board, the second electrolytic capacitor 41a is mounted in the first hole 120a, as in the electrolytic capacitor board, and the small-capacity capacitor 42 is mounted in the second hole 120b, as in the electrolytic capacitor board.

[0049] Furthermore, the pattern 240 includes a first pattern 240a on which the first electrolytic capacitor 41a or the second electrolytic capacitor 41a is mounted, and a second pattern 240b on which either the third electrolytic capacitors 41b-41g or the small-capacity capacitor 42 is mounted. Therefore, it is not necessary to provide a separate mounting location for the second electrolytic capacitor 41a when the printed circuit board 111 is used as a chemical-capacitor-less board, in addition to the mounting location for the first electrolytic capacitor 41a when the printed circuit board 111 is used as an electrolytic capacitor board. By using the printed circuit board 111, the electrolytic capacitor 41 can be shared between the electrolytic capacitor board and the chemical-capacitor-less board. For example, when the printed circuit board 111 is used as a chemical-capacitor-less board, the small-capacity capacitor 42 can be mounted in the same position as the electrolytic capacitor 41 on the electrolytic capacitor board, thereby reducing the space required on the printed circuit board 111.

[0050] Furthermore, when the printed circuit board 111 is used as an electrolytic capacitor board, a jumper 45 is connected to the third pattern 240c, and only the fourth pattern 240d is configured to be conductive. When the printed circuit board 111 is used as a chemical capacitor-less board, a diode 43 is connected to the third pattern 240c, and only the fourth pattern 240d is configured to be conductive. This allows the printed circuit board 111, when used as a chemical capacitor-less board, to absorb voltage fluctuations and release the charge accumulated in the second electrolytic capacitor 41a.

[0051] Furthermore, when the printed circuit board 111 is used as an electrolytic capacitor board, the number of resistors 44 connected to the fifth pattern 240e is greater than when the printed circuit board 111 is used as a chemical capacitor-less board. In a chemical capacitor-less board, only the second electrolytic capacitor 41a is mounted, so electric charge can be discharged using a smaller number of resistors 44 than when the printed circuit board 111 is used as an electrolytic capacitor board.

[0052] Additionally, the third pattern 240c, the fourth pattern 240d, and the fifth pattern 240e are all formed around the first pattern 240a, which shortens the path from the first electrolytic capacitor 41a or the second electrolytic capacitor 41a to the diode 43, the jumper 45, or the resistor 44, thereby reducing noise.

[0053] Furthermore, the same electrolytic capacitor can be used for the first electrolytic capacitor 41a mounted on the electrolytic capacitor substrate and the second electrolytic capacitor 41a mounted on the chemical-capacitor-less substrate, so the first electrolytic capacitor 41a mounted on the electrolytic capacitor substrate and the second electrolytic capacitor 41a mounted on the chemical-capacitor-less substrate are common, eliminating the need to prepare them separately.

[0054] Furthermore, the first electrolytic capacitor 41a mounted on the electrolytic capacitor board and the second electrolytic capacitor 41a mounted on the chemical-capacitor-less board are mounted on the first pattern 240a. In other words, an electrolytic capacitor board or a chemical-capacitor-less board can be realized using a single printed circuit board 111. Therefore, a configuration tailored to the user's needs can be realized without having to prepare separate printed circuit boards 111 for the electrolytic capacitor board and the chemical-capacitor-less board.

[0055] Furthermore, in the electric circuit 10, the electrolytic capacitor 41 is configured to be used to smooth the voltage of the power conversion device 100 when the printed circuit board 111 is used as an electrolytic capacitor board. Also, when the printed circuit board 111 is used as an electrolytic capacitor board, the electrolytic capacitor 41 is configured to be used to suppress voltage fluctuations in the power conversion device 100. Therefore, it is not necessary to prepare separate printed circuit boards 111 on which the electric circuit 10 is formed for each of the electrolytic capacitor board and the chemical-capacitor-less board. It is also not necessary to prepare separate components for each of the electrolytic capacitor board and the chemical-capacitor-less board.

[0056] The power conversion device 100 is configured by mounting the rectifier circuit 3, the inverter circuit 5, and the busbar circuit 4 on a printed circuit board 111, and the busbar circuit 4 is mounted with an electrolytic capacitor 41 or a small-capacity capacitor 42 having a smaller capacitance than the electrolytic capacitor 41. In other words, by switching between mounting the electrolytic capacitor 41 and the small-capacity capacitor 42, two types of power conversion devices 100 can be obtained with one type of printed circuit board 111: one that uses an electrolytic capacitor board and one that uses a chemical-capacitor-less board. This makes it possible to reduce the manufacturing costs and inventory costs associated with the power conversion device 100.

[0057] Embodiment 2. FIG. 8 is a schematic diagram showing an air conditioner 400 according to embodiment 2. As shown in FIG. 8, the air conditioner 400 includes a refrigeration cycle device 300 and a blower 401. In FIG. 7, the outline arrows indicate the flow of refrigerant. The blower 401 blows and circulates outdoor air. The refrigeration cycle device 300 includes a refrigerant compression device 200, a condenser 301, an expansion valve 302, and an evaporator 303. The refrigerant compression device 200 includes the compressor 201 and a power conversion device 100. The power conversion device 100 may include an electrolytic capacitor board or a chemical capacitor-less board. The compressor 201, the condenser 301, the expansion valve 302, and the evaporator 303 are connected by piping, and the refrigerant flows and circulates through the piping.

[0058] The compressor 201 includes an electric motor 2. The electric motor 2 is driven by power input from the power conversion device 100, and compresses the refrigerant gas inside the compressor 201 into a high-pressure gas. At this time, the power conversion device 100 is variably controlled in speed by an operation command from a control device (not shown).

[0059] In the refrigeration cycle device 300, the compressor 201 is driven to circulate a refrigerant through the piping of the refrigeration cycle device 300, and the circulating refrigerant repeatedly undergoes processes of evaporation, compression, condensation, and expansion. As a result, the refrigerant changes from a liquid to a gas and from the gas to a liquid, and heat is exchanged between the refrigerant and the outside air. The air conditioner 400 is configured by combining the refrigeration cycle device 300 with a blower 401 that circulates the outside air.

[0060] The power conversion device 100 has a printed circuit board 111 shown in Fig. 4 or 5, which is used as an electrolytic capacitor board or a chemical-capacitor-less board. By including the printed circuit board 111 in the power conversion device 100, it is not necessary to manufacture or stock an electrolytic capacitor board or a chemical-capacitor-less board, and the cost of parts can be reduced. As a result, an inexpensive air conditioner 400 can be provided.

[0061] In particular, since demand for air conditioners 400 is increasing in emerging countries, using the power conversion device 100 is significant in that it makes it possible to provide air conditioners 400 in which the motor 2 is variably controlled at low cost.

[0062] As described above, according to the air conditioner 400 according to the second embodiment, an electrolytic capacitor board or a chemical capacitor-less board can be provided using the printed circuit board 111. Therefore, with one type of printed circuit board 111, it is possible to provide either an air conditioner 400 that reduces vibration noise and complies with harmonic standards, or an inexpensive air conditioner 400, depending on the user's needs.

[0063] 1 AC power supply, 2 Electric motor, 3 Rectifier circuit, 3a First output terminal, 3b Second output terminal, 4 Busbar circuit, 5 Inverter circuit, 5a First input terminal, 5b Second input terminal, 6 Reactor, 10 Electric circuit, 11 Positive busbar, 12 Negative busbar, 41 Electrolytic capacitor, 41a First electrolytic capacitor, Second electrolytic capacitor, 41b Third electrolytic capacitor, 41c Third electrolytic capacitor, 41d Third electrolytic capacitor, 41e Third electrolytic capacitor, 41f Third electrolytic capacitor, 41g Third electrolytic capacitor, 42 Small capacity capacitor, 42a Small capacity capacitor, 42b Small capacity capacitor, 42c Small capacity capacitor, 43 Diode, 44 Resistor, 45 Jumper, 100 Power conversion device, 110 Base material, 111 Printed circuit board, 120 Hole, 120a First hole, 120b Second hole, 200 Refrigerant compression device, 201 compressor, 240 pattern, 240a first pattern, 240b second pattern, 240c third pattern, 240d fourth pattern, 240e fifth pattern, 300 refrigeration cycle device, 301 condenser, 302 expansion valve, 303 evaporator, 400 air conditioner, 401 blower.

Claims

1. A substrate formed of an insulator; A pattern is formed on the substrate, and a DC voltage unit connected to a rectifier and an inverter in a power conversion device is mounted on the pattern. The pattern is The DC voltage unit includes: a first setting comprising a plurality of first electrolytic capacitors; a second setting including a second electrolytic capacitor and a small-capacity capacitor having a smaller capacitance than the plurality of first electrolytic capacitors and a smaller capacitance than the second electrolytic capacitor; It is configured to implement either Printed circuit board.

2. the plurality of first electrolytic capacitors include one first electrolytic capacitor and a plurality of third electrolytic capacitors, The pattern includes a first pattern on which the one first electrolytic capacitor or the second electrolytic capacitor is mounted; a second pattern on which either the plurality of third electrolytic capacitors or the small-capacity capacitor is mounted; The printed circuit board of claim 1 .

3. The patterns include a third pattern and a fourth pattern arranged in parallel with each other and in series with the first pattern, In the first setting, a short circuit means is connected to the third pattern, and only the fourth pattern is conductive; In the second setting, A diode is connected to the third pattern, and only the fourth pattern is configured to be conductive. The printed circuit board according to claim 2 .

4. The third pattern and the fourth pattern are provided around the first pattern. The printed circuit board according to claim 3.

5. The pattern includes a fifth pattern arranged in parallel with the first pattern and configured to have a plurality of resistors connected in parallel, In the first setting, the number of the plurality of resistors connected to the fifth pattern is In the second setting, the number of the resistors is greater than the number of resistors connected to the fifth pattern. The printed circuit board according to any one of claims 2 to 4.

6. The fifth pattern is provided around the first pattern. The printed circuit board according to claim 5.

7. The first electrolytic capacitor and the second electrolytic capacitor are the same. The printed circuit board according to any one of claims 2 to 4.

8. The first electrolytic capacitor and the second electrolytic capacitor are The first setting and the second setting are mounted at the same position of the pattern. The printed circuit board according to any one of claims 2 to 4.

9. A printed circuit board according to any one of claims 1 to 4, The DC voltage unit mounted on the printed circuit board; having In the first setting, the plurality of first electrolytic capacitors are used to smooth a voltage of the power conversion device; In the second setting, the second electrolytic capacitor is configured to be used to suppress voltage fluctuations in the power conversion device. Electrical circuit.

10. A printed circuit board according to any one of claims 1 to 4, The DC voltage unit mounted on the printed circuit board; Equipped with The DC voltage section is composed of the plurality of first electrolytic capacitors, or the second electrolytic capacitor and the small-capacity capacitor. Power conversion equipment.

11. The power conversion device including the printed circuit board according to any one of claims 1 to 4; A compressor equipped with the power conversion device; An air conditioner having the above structure.