JP6367057B2 - Power supply device, air conditioner including the same, and control method for power supply device - Google Patents

Description

  The present invention relates to a power supply device, an air conditioner including the power supply device, and a method for controlling the power supply device.

  For example, harmonics generated from harmonic generators such as air conditioners reduce the efficiency of use and cause deterioration of power distribution / reception facilities, peripheral factories and their parts. (Currently, Ministry of Economy, Trade and Industry) announced "Technical Guidelines for Harmonic Suppression Measures for Consumers Receiving Power at High Voltage or Extra High Voltage" (hereinafter referred to as "Guidelines for Harmonic Suppression Measures"). In 1995, the Japan Electric Association issued the “Harmonic Suppression Countermeasure Technical Guidelines” as a private technical guideline that supplements and supplements the “Harmonic Suppression Countermeasure Guidelines”. Efforts are made to suppress harmonics generated from harmonic generators based on the suppression countermeasure technical guidelines.

  Patent Document 1 below describes an outdoor unit and a split-type air conditioner that is arranged separately in an indoor unit, and includes a power supply device that rectifies an AC voltage and a DC-DC converter that steps down the output of the power supply device. A technique for supplying drive power from a DC-DC converter to an indoor unit in a unit is disclosed.

Japanese Patent Laid-Open No. 4-6340

  By the way, it is necessary to calculate the amount of harmonic outflow when determining whether or not the harmonic generation device possessed by the consumer conforms to the harmonic countermeasure technical guidelines. In the process, (1) high voltage power reception is required. , (2) Building, (3) Judgment is made on the condition that all the phase advance capacitors have series reactors, and if all the conditions from (1) to (3) are satisfied, the study is terminated. The calculation of the equivalent capacity and the calculation of the harmonic outflow current in this step can be omitted. Moreover, on April 1, 2014, the harmonic suppression countermeasure technical guidelines were revised, and there was no equipment exceeding (4) conversion factor Ki = 1.8 in the above conditions (1) to (3). Thus, when all of (1) to (4) are satisfied, the calculation of equivalent capacity and harmonic outflow current can be omitted.

When considering an air conditioner for a store, if a three-phase bridge circuit (with DC side reactor and 6-pulse converter) is used as the power supply for the outdoor unit, the harmonic conversion factor is 1.8. When a single-phase bridge circuit (full-wave rectification method, no reactor) is used for the power supply, the harmonic conversion factor is 2.9. As a conversion factor of harmonics of the entire air conditioner, it is necessary to consider a set of indoor units and outdoor units. The harmonic conversion factor of the air conditioner for a store in this example is 1.8 to 2.9. It becomes the value between. If it does so, in the case of the conventional air conditioning apparatus, there existed a problem that the conditions of said (4) could not be satisfied.
Moreover, in the method of the above-mentioned Patent Document 1, electric power that is stepped down by a DC-DC converter provided in an outdoor unit is supplied to an indoor unit, and it is large to drive an indoor fan that requires a large output such as a store. There was a problem that it was necessary to pass an electric current.

  The present invention has been made to solve the above problem, and can satisfy one of the conditions for omitting the examination of the harmonic outflow current in the harmonic countermeasure technical guidelines, and the current flowing to the load of the indoor unit It is an object of the present invention to provide a power supply device capable of reducing the size of the power supply device, an air conditioner including the power supply device, and a control method for the power supply device.

In order to solve the above problems, the present invention employs the following means.
In the present invention, a diode is connected in a three-phase bridge to convert an AC voltage into a DC voltage, a rectifier that rectifies an AC power supply, a smoother that smoothes an output of the rectifier, and the smoother and a load. A first inverter connected to an electric motor of a certain outdoor unit, converting the DC voltage smoothed by the smoothing means into an AC voltage, supplying the AC voltage to the electric motor of the outdoor unit, and driving the electric motor of the outdoor unit And an indoor unit circuit connected to the outdoor unit circuit , wherein the indoor unit circuit is an indoor unit of the air conditioner. a charging unit for storing the power of the electric motor, the voltage across the smoothing means is inputted, said smoothed by the smoothing means, and converts the DC voltage charged in the charging unit into an AC voltage, the pre-Symbol chamber Machine electric motor To provide a power supply apparatus of an air conditioner comprising a second inverter means for driving, the.

  According to the present invention, the AC power source is rectified by the rectifying means in which the diode is three-phase bridge-connected in order to convert the AC voltage into the DC voltage, and the output of the rectifying means is smoothed and converted by the rectifying means. The DC voltage is converted into AC voltage in the first inverter means, and the electric motor of the outdoor unit is driven. The voltage at both ends of the smoothing means is input, and the DC voltage smoothed by the smoothing means is converted into an AC voltage by the second inverter means, and the electric motor of the indoor unit is driven.

  Thus, by using the output of the rectifying means (three-phase bridge) used as the power supply for the outdoor unit as it is as the power supply for the indoor unit, the AC voltage is converted to the DC voltage via the single-phase bridge as the power supply for the conventional indoor unit. Compared with the case where it is converted to, the number of parts can be reduced because a single-phase bridge is not required. Further, since the output of the three-phase bridge is used as it is as a power source for the indoor unit, a high voltage can be supplied to the indoor unit. Thereby, when a large output is required for the indoor unit, the current flowing through the indoor unit can be reduced as compared to supplying a voltage lower than the output of the three-phase bridge to the indoor unit.

Conventionally, since the power supply of the indoor unit has obtained AC power via a single-phase bridge connection, the conversion factor as an air conditioner including an outdoor unit and an indoor unit is a conversion factor of a single-phase bridge (for example, 2 .9) and a three-phase bridge conversion factor (for example, 1.8) are set to a plurality of values (that is, in this example, the conversion factor is between 1.8 and 2.9), and harmonics The study of spillage could not be omitted. According to the present invention, only the conversion factor of the three-phase bridge (rectifier circuit) commonly connected to the second inverter means and the first inverter means need be considered, and the conversion factor of the three-phase bridge is 1.8. Can satisfy one of the conditions for omitting the study of the harmonic outflow current.
In addition, satisfying one of the conditions for omitting the harmonic examination can simplify the harmonic countermeasure examination procedure and reduce the harmonic countermeasure cost.

  This invention provides the air conditioning apparatus provided with the power supply device of the said air conditioning apparatus.

In the present invention, a diode is connected in a three-phase bridge to convert an AC voltage into a DC voltage, a rectifier that rectifies an AC power supply, a smoother that smoothes an output of the rectifier, and the smoother and a load. A first inverter connected to an electric motor of a certain outdoor unit, converting the DC voltage smoothed by the smoothing means into an AC voltage, supplying the AC voltage to the electric motor of the outdoor unit, and driving the electric motor of the outdoor unit connected preparative and circuit outdoor machine with a circuit for the outdoor unit, a control method of a power supply apparatus of an air conditioning apparatus and a circuit for the indoor unit having a charging unit, the charging unit, the air a charging step of storing electric power for the electric motor of the indoor unit of conditioner, the voltage across the smoothing means is inputted, said smoothed by the smoothing means, and an AC voltage a DC voltage charged in the charging step Conversion, provides an inverter step of driving the motor before Symbol chamber machine, a control method of the power supply apparatus of an air conditioner having a.

  The present invention can satisfy one of the conditions for omitting the study of harmonic outflow current in the harmonic countermeasure technical guidelines, and can reduce the number of parts and reduce the current flowing to the load of the indoor unit. Play.

1 is a perspective view of a ceiling-embedded air conditioner according to an embodiment of the present invention. It is the schematic which shows the structure of the power supply circuit of the ceiling embedded type air conditioning apparatus which concerns on one Embodiment of this invention. It is the schematic which shows the structure of the power supply circuit of the conventional air conditioning apparatus for shops.

  Hereinafter, an embodiment of a power supply apparatus according to the present invention, an air conditioner including the power supply apparatus, and a control method for the power supply apparatus will be described with reference to the drawings.

In the present embodiment, a store-embedded ceiling air conditioner will be described as an example of an air conditioner to which the power supply device is applied, but the form of the air conditioner is not particularly limited.
FIG. 1 is a perspective view of a ceiling-embedded air conditioner (hereinafter referred to as “air conditioner”) to which the power supply device according to the present embodiment is applied.
As shown in FIG. 1, the air conditioner 1 includes an indoor unit 2 installed on the ceiling of the room and an outdoor unit 3 installed outside the room. The indoor unit 2 and the outdoor unit are arranged. 3 is connected to two refrigerant pipes 4 composed of a liquid pipe and a gas pipe via electric wiring 5.

  As shown in FIG. 1, the outdoor unit 3 includes a compressor 6 that compresses refrigerant, an outdoor heat exchanger 7 that exchanges heat between the refrigerant and outside air, an outdoor fan 8 that distributes outside air to the outdoor heat exchanger 7, and control. A box 9 and the like are provided. As shown in FIG. 1, the indoor unit 2 includes a unit main body 10 installed in the ceiling and a ceiling panel 11 attached to the lower part of the unit main body 10. In the unit main body 10, a turbo fan 12 is rotatably installed at the center via a fan motor (not shown), and an indoor heat exchanger 13 is installed so as to surround the turbo fan 12. A bell mouth 14 that guides indoor air to the turbo fan 12 is disposed below the turbo fan 12.

  A ceiling panel 11 is provided so as to cover the lower surface of the unit main body 10 described above. A square-shaped opening (air suction port) 15 for sucking room air is provided in the center of the ceiling panel 11, and a suction grill 16 is installed in the opening 15. The suction grill 16 is lifted and lowered with respect to the ceiling panel 11 so as to be lowered to the floor surface of the room together with a dust box 30 and the like constituting an air filter cleaning mechanism 22 described later via a wire 17 and a lifting motor (not shown). It is supposed to be free.

  The ceiling panel 11 is provided with four air outlets 18 corresponding to the four sides of the panel so as to surround the air inlet 15, and the indoor heat exchanger 13 is provided via the air outlet 18. The air cooled or heated in the room is blown into the room. In the four air outlets 18, flaps 19 for adjusting the direction of the blown air are provided so as to be independently rotatable.

  FIG. 2 is a diagram illustrating a schematic configuration of the power supply device 20 applied to the air-conditioning apparatus 1 according to the present embodiment. As shown in FIG. 2, the power supply device 20 according to the present embodiment is connected to an AC power supply 21 and includes an outdoor unit circuit 22, an indoor unit circuit 23, and a control unit 30. The machine circuit 22 and the indoor unit circuit 23 are connected by a jumper wiring. Further, the outdoor unit circuit 22 and the indoor unit circuit 23 and the control unit 30 are connected so as to be able to exchange information, and various control signals from the control unit 30 are sent to the outdoor unit circuit 22 and the indoor unit circuit 23. Output.

  The outdoor unit circuit 22 includes a rectifying unit (rectifying unit) 24 that converts AC power supplied from the AC power source 21 into DC power, a DC reactor L, a capacitor (smoothing unit) Ca, and a first inverter unit (first 1 inverter means) 25a, 25b, and the first inverter sections 25a, 25b drive the motors 26a, 26b of the outdoor unit 3 serving as loads, respectively. The motor 26a is, for example, the compressor 6 provided in the outdoor unit 3 of the air conditioner 1, and the motor 26b is, for example, the outdoor fan 8 provided in the outdoor unit 3 of the air conditioner 1.

The DC reactor L and the capacitor Ca are connected in series, and both terminals of this series circuit are connected to the output terminals of the rectifying unit 24, respectively.
The rectifying unit 24 is a rectifying circuit having a conversion coefficient Ki described in Table 201-2-1 of Harmonic Suppression Countermeasure Technical Guidelines (Nippon Electric Association) of “1.8” or less. In order to convert it into a DC voltage, a diode (not shown) is connected in a three-phase bridge to form a rectifier circuit, and the AC power supply 21 is rectified.
The capacitor Ca forms a smoothing circuit and smoothes the output of the rectifying unit 24.

  The first inverter unit 25a is connected between the capacitor Ca and the motor 26a of the outdoor unit 3, converts the DC voltage smoothed by the capacitor Ca into an AC voltage, and supplies the AC voltage to the motor 26a of the outdoor unit 3. The motor 26a of the machine 3 is driven. The first inverter unit 25b is connected between the capacitor Ca and the motor 26b of the outdoor unit 3, converts the DC voltage smoothed by the capacitor Ca into an AC voltage, and supplies the AC voltage to the motor 26b of the outdoor unit. 3 motor 26b is driven.

  Specifically, each of the first inverter units 25a and 25b includes, for example, a three-phase bridge circuit configured by including six switching elements. The first inverter units 25a and 25b include three phases including a DC voltage, a U phase, a V phase, and a W phase. A phase driving voltage is generated, and the generated three-phase driving voltage is supplied to the motors 26a and 26b. The speed and torque of the motors 26a and 26b are controlled by controlling on / off of the switching elements included in the first inverter units 25a and 25b by a control unit 30 (details will be described later).

The indoor unit circuit 23 includes a capacitor Cc and a second inverter unit (second inverter means) 25c. The second inverter unit 25c drives the motor 26c of the indoor unit 2. The motor 26c is a fan motor provided in the indoor unit 2 of the air conditioner 1, for example.
The capacitor Cc stores electric power for the motor 26c in the indoor unit circuit 23, and avoids a voltage drop in the inner and outer connecting lines due to a pulsed current flowing in the second inverter unit 25c.

The second inverter 25c receives the voltage across the capacitor Ca, converts the DC voltage smoothed and charged by the capacitor Ca and the capacitor Cc into an AC voltage, and drives the motor 26c of the indoor unit 2 of the air conditioner 1. . Here, the voltage input to the indoor unit side is input as it is without being adjusted from the indoor unit side (for example, if the voltage between terminals of the capacitor Ca is 300 [V], 300 [V] is input). .
The second inverter unit 25c includes, for example, a three-phase bridge circuit configured by including six switching elements, and generates a three-phase drive voltage including a U phase, a V phase, and a W phase from a DC voltage, The generated three-phase drive voltage is supplied to the motor 26c. The speed and torque of the motor 26c are controlled by controlling the ON / OFF of the switching element provided in the second inverter unit 25c by the control unit 30.

  Further, when a predetermined output is required for driving the motor 26c of the indoor unit 2, for example, when a voltage that is stepped down and reduced is supplied to the indoor unit 2, the indoor unit 2 is used to obtain the predetermined output. However, if the voltage output from the rectifying unit 24 is directly input to the indoor unit 2 without being adjusted as in the present embodiment, the motor 26c of the indoor unit 2 is required. The current flowing through can be reduced.

  The control unit 30 is, for example, an MPU (Micro Processing Unit), and includes a computer-readable recording medium on which a program for executing processing is recorded. The CPU stores the program recorded on the recording medium. Each processing is realized by reading the program to a main storage device such as a RAM and executing it. Examples of the computer-readable recording medium include a magnetic disk, a magneto-optical disk, and a semiconductor memory.

  For example, the control unit 30 generates a PWM signal for each phase so that the rotation speed of the compressor 6 matches the rotation speed command ω provided from a higher-level control device (not shown), and supplies the PWM signal to the first inverter 25a. The speed and torque of the motor 26a are controlled. Similarly, the control part 30 produces | generates a PWM signal for every phase, gives it to the 1st inverter 25b, and controls the speed and torque of the motor 26b. In addition, the control unit 30 generates a PWM signal for each phase and applies it to the second inverter 25c to control the speed and torque of the motor 26c.

  Here, the effect | action of the power supply device 20 applied to the air conditioning apparatus 1 which concerns on this embodiment is demonstrated. The AC power supplied from the AC power supply 21 is rectified by the rectifier 24 and converted into DC power. The converted DC voltage is smoothed by the capacitor Ca and output to the first inverter units 25a and 25b. At the same time, the DC voltage smoothed by the capacitor Ca is charged with the capacitor Cc with the same voltage value and input to the second inverter 25c. The first inverters 25a and 25b drive the motors 26a and 26b to be connected to the motors 26a and 26b, respectively, based on the control command of the control unit 30, thereby driving the motors 26a and 26b. Further, the second inverter 25c drives the motor 26c connected based on the control command of the control unit 30, whereby the motor 26c is driven.

  Thus, in this embodiment, since the voltage supply of the indoor unit 2 is performed from the rectifying unit 24 connected to the outdoor unit 3, the power source of the indoor unit 2 is conventionally supplied from the AC power source 21 to the single-phase bridge. Compared to the case obtained through a circuit, it is possible to reduce the parts for a single-phase bridge circuit. The harmonics of the air-conditioning apparatus 1 in the present embodiment need only be considered for the rectification unit 24, that is, only the harmonic conversion factor of the three-phase bridge circuit is considered (since no single-phase bridge circuit is used). Become.

Here, the harmonic conversion coefficient for each circuit type shown in the harmonic suppression countermeasure technical guidelines will be examined. The harmonic conversion coefficient described below is a value based on the conversion coefficient table (Table 201-2-1) shown in the harmonic suppression countermeasure technical guidelines.
The harmonic conversion coefficient indicates that the smaller the value, the smaller the harmonic.
As a harmonic suppression measure, a circuit configuration example of the air-conditioning apparatus 1 of the present embodiment is as shown in FIG. A schematic configuration of a power supply circuit of a conventional air conditioner is shown in FIG. FIG. 3 is a circuit example of a store air conditioner described in the harmonic suppression countermeasure technical guidelines. In FIG. 3, the same reference numerals are given to the same parts as those of the above-described embodiment.

As shown in FIG. 3, conventionally, the outdoor unit 3 has the same configuration as that of the above-described embodiment, and the rectifier 24 used as a power source is a circuit in which a diode is connected in a three-phase bridge, Therefore, the harmonic conversion coefficient K is K33 = 1.8. The indoor unit 2 is connected to an AC power source 21 and converts an AC voltage into a DC by a single-phase bridge circuit 50. When the single-phase bridge circuit 50 has no reactor, capacitor smoothing, and full-wave rectification, the harmonic conversion coefficient is K43 = 2.9.
The harmonic conversion coefficient of the air conditioner that combines the outdoor unit 3 and the indoor unit 2 as described above is a range including all values, that is, the harmonic conversion coefficient K of the conventional air conditioner is 1.8-2. The range is 9. Then, the condition that there is no device exceeding (4) conversion coefficient Ki = 1.8 of the harmonic suppression countermeasure technical guideline is not satisfied.

In FIG. 2 shown in the present embodiment, the power of the indoor unit 2 is obtained from the outdoor unit side, and the output (DC voltage) of the rectifying unit 24 is supplied to the indoor unit 2. As described above, the rectifying unit 24 used in the outdoor unit 3 of the present embodiment is a circuit in which a diode is connected in a three-phase bridge, and is a 6-pulse converter that uses a reactor on the DC side. Is K33 = 1.8. Moreover, since the power supply used for the indoor unit 2 of this embodiment uses the rectification part 24 calculated | required with the outdoor unit 3, there is nothing separately prepared for indoor units. Therefore, according to the air conditioning apparatus 1 according to the present embodiment, the harmonic conversion coefficient K is “1.8”.
That is, as described in the present embodiment, the power supply of the indoor unit 2 is obtained from the output side of the rectifying unit 24 of the outdoor unit 3 by using the rectifying unit 24 connected to the three-phase bridge having a harmonic conversion coefficient of 1.8 or less. By using the air conditioner 1, the condition of (4) no equipment exceeding the conversion coefficient Ki = 1.8, which is one condition of the harmonic suppression countermeasure technical guidelines, is satisfied.

  Thereby, by using the power supply device 20 shown in the present embodiment, harmonics can be suppressed and the number of parts on the indoor unit side can be reduced as compared with the configuration of the power supply circuit of a conventional store air conditioner. This leads to simplification of the study of harmonic suppression measures. Furthermore, the cost of harmonic suppression measures can be reduced.

  As described above, according to the air conditioner 1 and the control method thereof according to the present embodiment, the AC power supply 21 is rectified by the rectifying unit 24 in which the diode is connected to the three-phase bridge, and the AC voltage is converted into the DC voltage. The output of the rectifying unit 24 is smoothed, and the DC voltage converted by the rectifying unit 24 is supplied to the first inverter units 25a and 25b and converted into an AC voltage, and the motors 26a and 26b of the outdoor unit 3 are driven. Is done. The voltage between both ends of the capacitor Ca is input to the indoor unit 2 side, and the DC voltage smoothed by the capacitor Ca is charged by the capacitor Cc, converted into an AC voltage by the second inverter unit 25c, and the motor 26c of the indoor unit 2 Is driven.

  Thus, by using the output of the rectifying unit 24 used as the power source of the outdoor unit 3 as it is as the power source of the indoor unit 2, the AC voltage is converted into a DC voltage by a single-phase bridge as the power source of the conventional indoor unit 2. The number of parts can be reduced as compared with the case where it has been. Further, since the output of the three-phase bridge is used as it is as the power source for the indoor unit 2, a high voltage can be used, and the current to be flowed can be reduced as compared with the case where a low voltage is supplied as the power source for the indoor unit 2. .

Conventionally, since the power supply of the indoor unit 2 has been obtained with an AC power supply via a single-phase bridge connection, the conversion factor of the air conditioner 1 including the outdoor unit 3 and the indoor unit 2 is the conversion factor of the single-phase bridge. (E.g., 2.9) and three-phase bridge conversion coefficient (e.g., 1.8) are set to a plurality of values (i.e., the conversion coefficient is 1.8 to 2.9 in the example) The study of wave runoff could not be omitted. According to the present embodiment, only the conversion factor K of the three-phase bridge connected in common to the second inverter unit 25c and the first inverter units 25a and 25b may be considered, and the conversion factor K of the three-phase bridge is 1.8. In this case, one of the conditions for omitting the examination of the harmonic outflow current can be satisfied.
Moreover, the harmonic countermeasure examination procedure can be simplified by satisfying one of the conditions for omitting the harmonic examination. In addition, harmonic countermeasure costs can be reduced.

  In addition, this invention is not limited to embodiment mentioned above, In the range which does not deviate from the summary, it can change suitably.

Ca, Cc Capacitor L DC reactor 1 Air conditioner 2 Indoor unit 3 Outdoor unit 21 AC power supply 24 Rectifier unit 25a, 25b First inverter unit 25c Second inverter unit 26a, 26b Outdoor unit motor 26c Indoor unit motor

Claims (3)

A diode is connected in a three-phase bridge to convert an AC voltage into a DC voltage, a rectifier that rectifies an AC power supply, a smoother that smoothes the output of the rectifier, and a smoothing unit and an outdoor unit that is a load An outdoor unit having a first inverter unit that is connected between the motor and converts the DC voltage smoothed by the smoothing unit into an AC voltage and supplies the AC voltage to the motor of the outdoor unit and drives the motor of the outdoor unit; An air conditioner power supply device comprising: an air conditioner circuit; and an indoor unit circuit connected to the outdoor unit circuit ,
The indoor unit circuit is supplied with charging means for storing electric power for an electric motor of the indoor unit of the air conditioner, and the voltage across the smoothing unit is input, smoothed by the smoothing unit, and charged to the charging unit. DC voltage is converted into AC voltage, the power supply of the air conditioning apparatus comprising a second inverter means, a for driving the electric motor before Symbol chamber machine.   The air conditioning apparatus provided with the power supply device of the air conditioning apparatus of Claim 1. A diode is connected in a three-phase bridge to convert an AC voltage into a DC voltage, a rectifier that rectifies an AC power supply, a smoother that smoothes the output of the rectifier, and a smoothing unit and an outdoor unit that is a load An outdoor unit having a first inverter unit that is connected between the motor and converts the DC voltage smoothed by the smoothing unit into an AC voltage and supplies the AC voltage to the motor of the outdoor unit and drives the motor of the outdoor unit; A control method for a power supply device of an air conditioner , comprising: an indoor circuit; and an indoor unit circuit connected to the outdoor unit circuit and having a charging means ,
A charging step for storing electric power for an electric motor of the indoor unit of the air conditioner in the charging unit;
The voltage across the smoothing means is inputted, said smoothed by the smoothing means, and inverter process the converted into an AC voltage to charge DC voltage in the charging process, to drive the electric motor before Symbol chamber machine,
A control method for a power supply device of an air conditioning apparatus having

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