JP6823214B1 - Circuit boards, circuits and air conditioners - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a circuit board capable of selecting a configuration corresponding to different specifications, a circuit using this circuit board, and an air conditioner including the circuit. SOLUTION: A circuit board on which at least a diode bridge DB1 and a smoothing capacitor C1 are mounted, and a first diode arrangement portion D1 and a second diode arrangement portion D2 having a pair of conductor land patterns on which a diode can be mounted. , The switching unit JP1 which has a pair of conductor land patterns on which short-circuit components can be mounted and can switch between short-circuiting and opening depending on the presence or absence of mounting of short-circuit components, and the first conductor land pattern of the switching unit JP1 are smooth. The wiring pattern in which the capacitor C1, the conductor land pattern K on the cathode side of the first diode arrangement portion D1 and the conductor land pattern K on the cathode side of the second diode arrangement portion D2 are connected, and the second conductor of the switching portion JP1. It includes a land pattern and a wiring pattern to which the diode bridge DB1 is connected. [Selection diagram] Fig. 3

Description

The present invention relates to a circuit board, a circuit, and an air conditioner including the circuit, which can select a configuration corresponding to different specifications depending on whether or not a component is mounted.

Generally, an air conditioner is configured by mounting a power factor improving circuit between an AC power supply and an inverter circuit that drives a motor, and suppresses harmonic current generated when the inverter circuit is driven by the power factor improving circuit. .. As a technique for suppressing the harmonic current of the power factor improving circuit, for example, the air conditioner shown in Patent Document 1 and Patent Document 2 has been developed.

Harmonic currents have different standards required by countries and regions (hereinafter, countries and regions are collectively referred to as "regions"). An example of a standard that regulates harmonic currents is the IEC (International Electrotechnical Commission) standard, which is adopted in regions such as China and Europe. On the other hand, there are areas where regulations on harmonic currents are relatively loose. For example, in Japan, regulations on harmonic currents are reduced for air conditioners with an input power of more than 600 W. Therefore, different power factor improvement circuits have been installed in air conditioners for regions where strict regulations are required and air conditioners for regions where strict regulations are required.

By the way, in order to reduce the development cost and evaluation time of the circuit board, there is a demand that the specifications differ depending on the common circuit board. For example, Patent Document 3 discloses a circuit board that can correspond to different specifications by selecting a connection of a wiring pattern.

However, Patent Document 3 is a technique for standardizing the circuit board in order to make the creepage distance of the discharge portion correspond to the standard, and is a circuit for corresponding to harmonic currents having different standards depending on the destination as described above. The board was not developed. Therefore, there has been a demand for a common circuit board that can be used for destinations with different harmonic current specifications in air conditioners.

Japanese Unexamined Patent Publication No. 4-26374 Japanese Unexamined Patent Publication No. 2008-259422 Japanese Unexamined Patent Publication No. 2014-225616

The present invention has been made in view of the above problems in the prior art, and provides a circuit board capable of selecting a configuration corresponding to different specifications, a circuit using this circuit board, and an air conditioner including this circuit. The purpose.

That is, according to the present invention.
A circuit board on which at least a diode bridge and a smoothing capacitor are mounted.
A first diode arrangement and a second diode arrangement having a pair of conductor land patterns on which diodes can be mounted,
A switching unit having a pair of conductor land patterns on which short-circuit components can be mounted, and switching between short-circuiting and opening between the pair of conductor land patterns depending on whether or not the short-circuit components are mounted.
The first conductor land pattern of the switching portion, the smoothing capacitor, the conductor land pattern on the cathode side of the first diode arrangement portion, and the conductor land pattern on the cathode side of the second diode arrangement portion are connected. Wiring pattern to be done and
Provided is a circuit board comprising a second conductor land pattern of the switching portion and a wiring pattern to which the diode bridge is connected.

According to the present invention, it is possible to provide a circuit board capable of selecting configurations corresponding to different specifications, a circuit using this circuit board, and an air conditioner including the circuit.

The figure which shows the circuit diagram and the example of the current waveform of the power factor improvement circuit for the area where the IEC standard is not applied in the prior art. The figure which shows the circuit diagram and the example of the current waveform of the power factor improvement circuit for the IEC standard application area in the prior art. The figure which shows each current path at the time of switching in the conventional power factor improvement circuit. The figure which shows the circuit board configuration in this embodiment. The circuit diagram which configured the IEC standard non-applicable circuit in the circuit board of this embodiment. The circuit diagram which configured the IEC standard application circuit in the circuit board of this embodiment.

Hereinafter, the present invention will be described with reference to embodiments, but the present invention is not limited to the embodiments described later. In each of the figures referred to below, the same reference numerals are used for common elements, and the description thereof will be omitted as appropriate.

In the embodiments described below, in order to conveniently distinguish between areas where the regulation on harmonic current of the air conditioner is relatively loose and areas where strict regulation is required, "IEC standard non-applicable area" is used. , "IEC standard applicable area". Further, the power factor improvement circuit for the IEC standard non-applicable area is referred to as "IEC standard non-applicable circuit", and the power factor improvement circuit for the IEC standard applicable area is referred to as "IEC standard applicable circuit". However, the above distinction is for convenience and does not necessarily have to be distinguished by the application / non-application of the IEC standard. That is, the generated harmonic current may be distinguished between a region where the regulation is relatively loose and a region where the regulation is relatively strict.

The circuit configurations of the IEC standard non-applicable circuit and the IEC standard applicable circuit in the prior art will be described with reference to FIGS. 1 and 2. First, FIG. 1 will be described. FIG. 1 is a diagram showing a circuit diagram and an example of a current waveform of a power factor improvement circuit for areas where the IEC standard is not applied in the prior art.

As shown in FIG. 1A, the IEC standard non-applicable circuit in the prior art is composed of a diode bridge DB1, DB2, a reactance element L1, a switching element Q1, and a smoothing capacitor C1, and is connected to an AC power supply 100.

When the switching element Q1 is on, a current flows through the path indicated by the gray arrow in FIG. 1 (a). Here, when the switching element Q1 is switched a plurality of times, the recovery current indicated by the broken line arrow is generated from the smoothing capacitor C1. Since the diode constituting the diode bridge DB1 has a relatively long reverse recovery time, the recovery current cannot be suppressed, and the recovery current flows to the AC power supply 100 side. Therefore, since the power supply system may be adversely affected, the IEC standard non-applicable circuit having poor harmonic current characteristics can switch only once for a half cycle of the frequency of the power supply.

FIG. 1B is a graph showing an example of a current waveform of a circuit to which the IEC standard is not applied. The horizontal axis shows time and the vertical axis shows current. The sharp-shaped waveform seen in the broken line region in FIG. 1B is due to switching by the switching element Q1. Since the circuit to which the IEC standard is not applied has poor harmonic current characteristics, as shown in FIG. 1 (b), switching can be performed only once for a half cycle of the frequency of the power supply.

Next, FIG. 2 will be described. As described above, the IEC standard non-applicable circuit has poor harmonic current characteristics and is therefore unsuitable for the IEC standard applicable area. Therefore, when the destination is the IEC standard application area, it is necessary to use a circuit having specifications that satisfy strict harmonic current standards. FIG. 2 is a diagram showing a circuit diagram and an example of a current waveform of a power factor improvement circuit for an IEC standard application area in the prior art.

As shown in FIG. 2A, the IEC standard application circuit in the prior art is composed of a diode bridge DB1, a reactance element L1, a switching element Q1, a smoothing capacitor C1, and a diode D1 and is connected to an AC power supply 100. Here, the diode D1 is a so-called fast recovery diode (FRD) having a relatively short reverse recovery time.

When the switching element Q1 is on, a current flows through the path indicated by the gray arrow in FIG. 2A. Here, when the switching element Q1 is switched a plurality of times, the recovery current indicated by the broken line arrow is generated from the smoothing capacitor C1. Since the fast recovery diode is mounted in the IEC standard application circuit, it is possible to suppress the recovery current from flowing to the AC power supply 100 side. Therefore, in the IEC standard application circuit, the harmonic current characteristic is good, and switching is possible twice or more for a half cycle of the frequency of the power supply.

FIG. 2B is a graph showing an example of a current waveform of an IEC standard application circuit, in which the horizontal axis represents time and the vertical axis represents current. The sharp-shaped waveform seen in the broken line region in FIG. 2B is due to switching by the switching element Q1. Since the IEC standard application circuit has good harmonic current characteristics, as shown in FIG. 2B, switching is possible twice or more for a half cycle of the frequency of the power supply.

By the way, as described above, the IEC standard application circuit is excellent in harmonic current characteristics and can appropriately suppress the recovery current. Therefore, it is also possible to mount the IEC standard application circuit on the air conditioner whose destination is the area where the IEC standard is not applied. However, as described with reference to FIG. 3 below, the circuit to which the IEC standard is applied in the prior art has lower circuit efficiency than the circuit to which the IEC standard is not applied. Therefore, it is preferable that the air conditioner is equipped with a power factor improving circuit suitable for the specifications required at the destination.

FIG. 3 is a diagram showing each current path when switching is performed in the conventional power factor improving circuit. FIG. 3A shows the current path of the same IEC standard non-applicable circuit as the circuit shown in FIG. 1, and FIG. 3B shows the current path of the same IEC standard applicable circuit as the circuit shown in FIG. Is shown. Further, the path A indicated by the gray arrow in FIGS. 3A and 3B is the current path when the switching element Q1 is in the ON state, and the path B indicated by the broken line arrow is the switching element Q1. Is the current path when is in the off state.

In the IEC standard non-applicable circuit, as shown in FIG. 3A, both the current flowing when the switching element Q1 is on (path A) and the current flowing when the switching element Q1 is off (path B) constitute the diode bridge DB1 or DB2. It will pass through two diodes.

On the other hand, in the IEC standard application circuit, as shown in FIG. 3B, the current (path A) flowing when the switching element Q1 is in the ON state passes through the two diodes constituting the diode bridge DB1. However, the current (path B) that flows when the switching element Q1 is in the off state passes through three diodes including the two diodes constituting the diode bridge DB1 and the diode D1. Since the loss increases when a current flows through the diode, the circuit efficiency of the IEC standard applicable circuit is lower than that of the IEC standard non-applied circuit. Therefore, it is preferable that the air conditioner is equipped with a power factor improving circuit according to the standard of the destination.

As described above, the air conditioner is equipped with the power factor improving circuits shown in FIGS. 1 and 2 according to the destination. On the other hand, the IEC standard non-applicable circuit shown in FIG. 1 and the IEC standard applicable circuit shown in FIG. 2 have many parts in common. Therefore, from the viewpoint of reducing the cost and evaluation time required for the development of the circuit board, it is preferable to standardize the circuit board of the circuit to which the IEC standard is not applied and the circuit board of the circuit to which the IEC standard is applied. Therefore, by adopting the configuration shown in the embodiment described below, the circuit board of the IEC standard non-applicable circuit and the circuit board of the IEC standard applicable circuit can be shared. FIG. 4 is a diagram showing a circuit board configuration according to the present embodiment.

As shown in FIG. 4, the circuit board of the present embodiment is configured to include an arrangement portion for arranging each component of the diode bridge DB1, DB2, the reactance element L1, the switching element Q1, and the smoothing capacitor C1, and is configured with the AC power supply 100. It has a wiring pattern to be connected. Further, the circuit board of the present embodiment is configured to include diode arrangement portions D1 and D2 and jumper arrangement portions JP1.

The diode arrangement portions D1 and D2 have a pair of conductor land patterns on which a diode can be mounted, and the diode can be mounted between the conductor land patterns by soldering or the like. The symbols "A" and "K" in the vicinity of the diode arrangement portions D1 and D2 in FIG. 4 indicate the anode terminal and the cathode terminal of the diode, respectively. Further, the diode arrangement portions D1 and D2 can electrically open the conductor land patterns without mounting the diode. The term "conductor land pattern" in the embodiment to be described refers to a conductor pattern used for mounting a component, and examples thereof include a pad for surface mounting and a component mounting hole in a through-hole substrate.

The jumper arrangement portion JP1 has a pair of conductor land patterns on which short-circuit parts can be mounted.
Conductors such as jumper wires and so-called zero ohm resistors can be mounted. As a result, the conductor land patterns of the jumper arrangement portion JP1 can be electrically short-circuited (hereinafter, the parts used exclusively for electrical short-circuiting such as jumper wires and zero ohm resistors are collectively referred to. Referred to as "short-circuit component"). The jumper arrangement portion JP1 can switch between electrical short circuit (short circuit) and open (open) between conductor land patterns depending on whether or not a short circuit component is mounted. That is, the jumper arrangement unit JP1 functions as a switching unit that can selectively switch between short circuit and open circuit.

Further, the circuit board in the present embodiment has a wiring pattern in which each component is electrically connected as shown in FIG. More specifically, the circuit board of the present embodiment includes one conductor land pattern of the jumper arrangement portion JP1, a smoothing capacitor C1, a conductor land pattern on the cathode side of the first diode arrangement portion D1, and a second conductor land pattern. It has a wiring pattern in which the conductor land pattern on the cathode side of the diode arrangement portion D2 is connected. Further, the circuit board of the present embodiment has a wiring pattern in which the other conductor land pattern of the jumper arrangement portion JP1 and the terminal on the output side of the diode bridge DB1 are connected.

By using the circuit board having the wiring pattern shown in FIG. 4, the circuit board of the circuit to which the IEC standard is not applied and the circuit board of the circuit to which the IEC standard is applied can be shared. That is, in the circuit board having the configuration shown in FIG. 4, the IEC standard non-applicable circuit can be obtained by appropriately combining the presence / absence of the diode and the short-circuit component mounted on the diode arrangement portions D1 and D2 and the jumper arrangement portion JP1. It is possible to select whether to use an IEC standard applicable circuit.

Therefore, the IEC standard non-applicable circuit and the IEC standard applicable circuit configured by using the circuit board of the present embodiment shown in FIG. 4 will be described with reference to FIGS. 5 and 6. FIG. 5 is a circuit diagram in which an IEC standard non-applicable circuit is configured on the circuit board of the present embodiment. Further, FIG. 6 is a circuit diagram constituting an IEC standard application circuit in the circuit board of the present embodiment. In the following description of FIGS. 5 and 6, Table 1 below shall be referred to as appropriate. Table 1 is a table showing the states of the diode arrangement units D1 and D2 and the jumper arrangement unit JP1 when the IEC standard non-applicable circuit configuration and the IEC standard application circuit configuration are used.

When a circuit to which the IEC standard is not applied is configured on the circuit board of the present embodiment, the configuration is as shown in FIG. 5 and Table 1. That is, no component is mounted on the diode arrangement portions D1 and D2, and the conductor land patterns are electrically opened. Further, a short-circuit component is mounted on the jumper arrangement portion JP1 to electrically short-circuit between the conductor land patterns. As a result, a circuit corresponding to the IEC standard non-applicable circuit shown in FIG. 1 can be configured. The gray arrow in FIG. 5 indicates the current path when the switching element Q1 is in the off state.

On the other hand, when the IEC standard application circuit is configured on the circuit board of the present embodiment, the configuration is as shown in FIG. 6 and Table 1. That is, a diode is mounted on the diode arrangement portions D1 and D2. The diode mounted on the diode arrangement portions D1 and D2 is preferably a fast recovery diode having a short reverse recovery time. For example, the diode has a shorter reverse recovery time than the diodes constituting the diode bridges DB1 and DB2. Is preferable. Further, the jumper arrangement portion JP1 is not mounted with a short-circuit component, and the conductor land patterns are electrically opened. As a result, a circuit corresponding to the IEC standard application circuit shown in FIG. 2 can be configured. The gray arrow in FIG. 6 indicates the current path when the switching element Q1 is in the off state, and the broken line arrow indicates the recovery current generated when the switching element Q1 switches. As shown in FIG. 6, the diodes arranged in the diode arrangement portions D1 and D2 can suppress the recovery current from flowing to the AC power supply 100 side. Further, even when the switching element Q1 is in the off state, the number of diodes through which the current passes is two, and the circuit efficiency can be improved.

As described above, by adopting the circuit configuration of the present embodiment, the circuit board of the IEC standard non-applicable circuit and the circuit board of the IEC standard applicable circuit can be shared. Therefore, it is possible to select whether to use the IEC standard non-applicable circuit or the IEC standard applicable circuit depending on whether or not the components are mounted on the same circuit board. Further, by sharing the circuit board, the development cost and evaluation time of the circuit board can be reduced.

According to each embodiment of the present invention described above, it is possible to provide a circuit board capable of selecting configurations corresponding to different specifications, a circuit using this circuit board, and an air conditioner including this circuit.

The circuit board in the above-described embodiment is not particularly limited to the embodiment, but may be a general printed circuit board. Further, the form of mounting the component is not particularly limited, and any form such as surface mounting or through-hole mounting can be applied. Therefore, the components to be mounted are not particularly limited, and chip components, lead components, and the like can be arbitrarily selected and used.

Although the present invention has been described above with embodiments, the present invention is not limited to the above-described embodiments, and as long as the present invention exerts its actions and effects within the range of embodiments that can be inferred by those skilled in the art. , Is included in the scope of the present invention.

JP1 ... Jumper placement part,
D1, D2 ... Diode (diode arrangement part),
C1 ... Smoothing capacitor,
DB1, DB2 ... Diode bridge,
L1 ... reactance element,
Q1 ... Switching element,
100 ... AC power supply

Claims (5)

A circuit board on which at least a diode bridge and a smoothing capacitor are mounted.
A first diode arrangement and a second diode arrangement having a pair of conductor land patterns on which diodes can be mounted,
A switching unit having a pair of conductor land patterns on which short-circuit components can be mounted, and switching between short-circuiting and opening between the pair of conductor land patterns depending on whether or not the short-circuit components are mounted.
The first conductor land pattern of the switching portion, the smoothing capacitor, the conductor land pattern on the cathode side of the first diode arrangement portion, and the conductor land pattern on the cathode side of the second diode arrangement portion are connected. Wiring pattern to be done and
A circuit board including a second conductor land pattern of the switching portion and a wiring pattern to which the diode bridge is connected. By not mounting a diode in the first diode arrangement portion and the second diode arrangement portion of the circuit board according to claim 1, the first diode arrangement portion and the second diode arrangement portion can be separated from each other. Open the conductor land pattern,
The switching portion of the circuit board is short-circuited.
circuit. A diode is mounted on the first diode arrangement portion and the second diode arrangement portion of the circuit board according to claim 1.
The switching portion of the circuit board is opened.
circuit. The circuit according to claim 3, wherein the diode mounted on the first diode arrangement portion and the second diode arrangement portion has a shorter reverse recovery time than the diode constituting the diode bridge. .. An air conditioner comprising the circuit according to any one of claims 2 to 4.