JP2006292324A - Air conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prohibit operation of an inverter in the event of failure of any one phase of a three-phase AC power soruce with a simple structure to protect the inverter. <P>SOLUTION: This air conditioner comprises an outdoor control power source part 2A, an indoor control power source part 2B, an outdoor communication means 11A, an indoor communication means 11B, a communication power supply part 5 and an inverter control part 4. Power supply to the communication power supply part 5 is performed from predetermined two phases of the three-phase AC power source 1, and power supply to the outdoor control power supply part 2A and the indoor control power supply part 2B is performed two phase including the remaining one phase, and when communication between the outdoor communication means 11A and the indoor communication means 11B is not established, operation of the inverter control part 4 is prohibited, whereby operation of the inverter can be prohibited in the event of failure of any one phase of the three-phase AC power source 1. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an air conditioner connected to a three-phase AC power source, and more particularly to improvement of measures for phase loss protection of a power source.

  Conventionally, as the phase loss protection of the equipment connected to the three-phase AC power supply, there is what detects the phase loss by detecting the DC voltage obtained by rectifying and smoothing the three-phase AC and comparing it with a predetermined level, It is also used for an air conditioner connected to a three-phase AC power source (see Patent Document 1).

  FIG. 3 shows a simplified configuration of the prior art described in Patent Document 1. The three-phase AC power source 1 and the three-phase rectification unit 7 which is a DC conversion means are connected via a three-phase normally open contact 12. A smoothing capacitor 8 and a DC voltage are connected to the DC output terminal of the three-phase rectification unit 7. Is connected to an inverter 10 that performs frequency conversion. A predetermined two-phase (for example, a three-phase AC power source 1) (for example, an inverter control unit 4 that controls the inverter 10 and a contact control unit (not shown) that controls the three-phase normally-open contact 12). Power is supplied by the control power supply unit 2 that receives power supply from the S phase and the T phase. Further, one phase (R phase) other than the predetermined two phases and the remaining one phase (for example, T phase) are normally opened between the three-phase AC power source 1 and the AC input terminal of the three-phase rectifier 7. The contact 13 and the current limiting unit 14 are connected.

  When the inverter 10 operates, the two-phase normally open contact 13 is first closed, and the smoothing capacitor 8 is charged while the inrush current is suppressed by the current limiting unit 14. After a predetermined time elapses, it is determined whether the DC voltage detected by the voltage detector 9 is equal to or higher than a predetermined level, the three-phase normally open contact 12 is closed, and then the inverter 10 is operated. If the detected DC voltage is less than a predetermined level, the control prohibiting unit 15 that prohibits the operation of the inverter prohibits the operation of the inverter control unit 4.

Here, when one of the two predetermined phases to which the control power supply unit 2 is connected is lost, power cannot be supplied to the device control unit 6, so that the entire device does not operate. Further, when the remaining one phase is lost, the smoothing capacitor 8 is not charged even if the two-phase normally open contact 13 operates, so that the three-phase normally open contact 12 and the inverter 10 do not operate as described above. The device is protected when one of the three-phase AC power supplies 1 is open.
JP-A-2-269480

  However, in the above-described conventional configuration, the two-phase normally open contact 13 operates when any one phase of the three-phase AC power source 1 is open, so that it can be determined that the phase is open when the voltage detection unit 9 is abnormal, for example. Therefore, there is a problem that the inverter 10 may be operated.

  Further, there has been a problem that the phase loss detection cannot be performed after the smoothing capacitor 8 is completely charged, that is, when the phase of the three-phase AC power source is lost during the inverter operation.

  The present invention solves the above-mentioned conventional problem, and is a case where a phase failure occurs without operating the inverter even when any phase of the three-phase AC power source is lost. It is another object of the present invention to provide an air conditioner that can reliably stop an inverter.

  In order to solve the above-described conventional problems, the air conditioner of the present invention performs power supply to the device control units of the indoor unit and the outdoor unit from predetermined two phases of a three-phase AC power source, and the indoor unit and the outdoor unit The power supply to the communication means provided in is performed from one of the predetermined two phases and the remaining one phase. As a result, when one of the two phases supplying power to the device control unit is lost, power is not supplied to the device control unit of the indoor unit and the outdoor unit, so the outdoor unit and the outdoor unit do not operate. Does not work. In addition, when the remaining one phase is lost, the power supply to the communication means is lost, so that the indoor unit and the outdoor unit cannot communicate, and it is determined that the communication is abnormal and the operation of the inverter is prohibited or stopped. That is, if any one phase of the three-phase AC power supply is lost, the operation of the inverter can be prohibited or stopped.

  The air conditioner of the present invention has a simple configuration, and when any one of the three-phase AC power supplies is lost, the operation of the inverter is stopped or prohibited regardless of whether the inverter is operating or stopped. Can be protected.

  According to a first aspect of the present invention, power is supplied to the indoor unit control unit and the outdoor unit control unit for controlling the indoor unit and the outdoor unit by a predetermined two-phase three-phase AC power supply, and the indoor unit and the outdoor unit are provided respectively. The power supply to the indoor communication means and the outdoor communication means is supplied from two phases including the remaining one phase, and control of the inverter is prohibited or stopped when communication is not established between the indoor unit and the outdoor unit Thus, when any one phase of the three-phase AC power supply is lost, the inverter can be prevented from operating.

  In addition to the first invention, the second invention has a configuration in which the DC voltage of the smoothing capacitor connected to the DC output terminal of the three-phase rectifier circuit is detected by the voltage detection means, thereby achieving the effect of the first invention. In addition, the operation of the inverter can be stopped when the power supply voltage drops due to phase loss during operation.

  In addition to the second invention, the third invention provides a three-phase normally open contact between the three-phase AC power supply and the three-phase rectifier circuit, and supplies power to the indoor communication means and the outdoor communication means. By connecting to the AC input terminal of the three-phase rectifier circuit via the two-phase normally open contact and the current limiter, it is possible to detect a charging failure to the smoothing capacitor when the current limiter breaks. By not operating the three-phase normally open contact, it is possible to prevent inrush current from being generated through the three-phase normally open contact, and to distinguish between a power supply phase loss and a defective charging circuit such as a current limiter. It becomes possible.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 shows a block diagram of a control device for an air-conditioning apparatus according to Embodiment 1 of the present invention.

  In FIG. 1, the same components as those in FIG. Reference numeral 1 denotes a three-phase AC power source, which is connected to a DC input terminal of the three-phase rectification unit 7. A smoothing capacitor 8 is connected to the DC output terminal of the three-phase rectifier 7 to supply a DC voltage to the inverter 10.

The indoor device control unit 6B, which is an indoor control means for controlling the indoor unit, is supplied to a control circuit (not shown) that determines and controls the drive of a fan motor (not shown) and the input of various sensors (not shown). An indoor control power supply unit 2B that supplies power is provided, and the indoor control power supply unit 2B receives power supply from the S phase and the T phase of the three-phase AC power supply 1.

  Similarly, the outdoor device control unit 6A, which is an outdoor control unit that controls the outdoor unit, supplies power to the inverter control unit 4 that drives and controls the inverter 10, a fan motor (not shown), various valve mechanisms (not shown), and the like. It has an outdoor control power supply unit 2A that supplies power and receives power supply from the S phase and T phase of the three-phase AC power supply 1. The inverter control unit 4 drives and controls the inverter 10 and operates the compressor 3 connected to the inverter 10 at a desired rotation speed.

  On the other hand, the outdoor device control unit 6A and the indoor device control unit 6B have an outdoor communication unit 11A and an indoor communication unit 11B, respectively, and transmit various temperatures, operation information of the inverter 10, and the like by communication. The communication power supply unit 5 that supplies power to the outdoor communication unit 11A and the indoor communication unit 11B receives power supply from the R phase and the T phase of the three-phase AC power source 1.

  The operation and action of the control device for the air conditioner configured as described above will be described below.

  When the S-phase or T-phase of the three-phase AC power supply 1 is lost, power is not supplied to the outdoor control power supply unit 2A, so that the inverter control unit 4 does not operate and the inverter 10 does not operate. When the R phase is lost, the communication power supply unit 5 is not supplied with power, so the outdoor communication unit 11A and the indoor communication unit 11B do not operate, and communication between the indoor unit and the outdoor unit is not established, and the operation from the room is performed. Since there is no instruction information, the inverter control unit 4 prohibits the operation of the inverter 10 and does not operate it.

  Thereby, when any phase of the three-phase AC power supply 1 is lost, the operation of the inverter 10 can be prohibited.

  In addition, when the outdoor communication unit 11A and the indoor communication unit 11B cannot communicate with each other, the operation of the inverter control unit 4 is stopped so that any one of the three-phase AC power sources 1 can be used in a situation where the inverter 10 is already operating. Even in the case where these phases are lost, the operation of the inverter 10 can be stopped.

(Embodiment 2)
FIG. 2 shows a block diagram of a control device for an air-conditioning apparatus according to Embodiment 2 of the present invention. In FIG. 2, the same components as those in FIG.

  The three-phase AC power source 1 and the three-phase rectification unit 7 are connected via a three-phase normally open contact 12, and other than the S phase and T phase to which the outdoor control power source unit 2A and the indoor control power source unit 2B are connected. A two-phase normally open contact 13 and a current limiting unit 14 are connected in parallel to the three-phase normally open contact 12 in the phase, that is, the R phase and the remaining one phase (here, the T phase). A voltage detection unit 9 that detects a DC voltage is connected to the DC output terminal of the three-phase rectification unit 7, and the output is input to an inverter control prohibiting unit 15 provided in the outdoor device control unit 6A.

  The operation and action of the control device for the air conditioner configured as described above will be described below.

When the operation instruction from the room is transmitted from the indoor communication unit 11B to the outdoor communication unit 11A and the inverter 10 needs to be operated, the outdoor device control unit 6A closes the two-phase normally open contact 13 and the current limiting unit 14, the smoothing capacitor 8 is charged via the three-phase rectification unit 7 from the R-phase and S-phase of the three-phase AC power source. After a predetermined time elapses, the voltage detection unit 9 detects the voltage across the smoothing capacitor, and if a value equal to or higher than the predetermined voltage is detected, the inverter control prohibiting unit 15 cancels the operation prohibition of the inverter control unit 4. The three-phase normally open contact 12 is closed. The inverter control unit 4 drives and controls the inverter 10 to operate the compressor 3 connected to the inverter 10 at a desired rotation speed. When the S-phase or T-phase of the three-phase AC power supply 1 is lost, power is not supplied to the outdoor control power supply unit 2A, so that the inverter control unit 4 does not operate and the inverter 10 does not operate.

  When the R phase is lost, the communication power supply unit 5 is not supplied with power, so the outdoor communication unit 11A and the indoor communication unit 11B do not operate, and communication between the indoor unit and the outdoor unit is not established, so that the operation from the room is performed. Since there is no instruction information, the inverter control unit 4 prohibits the operation of the inverter 10 and does not operate it.

  Here, when the current limiting unit 14 is broken or when the two-phase normally open contact 13 is not closed, even when the outdoor device control unit 6A operates the two-phase normally open contact 13, the smoothing capacitor 8 is supplied. Is not charged, the voltage detection unit 9 cannot detect a predetermined voltage or higher, and the inverter control prohibiting unit 15 prohibits the operation of the inverter control unit 4 and does not operate the three-phase normally open contact 12. Thereby, it is possible to prevent an inrush current from flowing into the smoothing capacitor 8 through the three-phase normally open contact 12.

  However, since the communication between the outdoor communication means 11A and the indoor communication means 11B needs to be established in order to operate the two-phase normally open contact 13, the communication power supply for supplying power to the outdoor communication means 11A and the indoor communication means 11B The supply unit 5 and the outdoor control power supply unit 2 </ b> A can determine that the power is normally supplied from the three-phase AC power supply 1. That is, since it is clear that the three-phase AC power supply 1 is not open phase, when the voltage detection unit 9 cannot detect a value equal to or higher than a predetermined voltage, the two-phase normally open contact 13 or the current limiting unit 14 is abnormal. It becomes clear, and it becomes possible to distinguish clearly from abnormality of the three-phase alternating current power supply 1. FIG.

  As described above, the control device for an air conditioner according to the present invention is configured such that the predetermined two phases of the three-phase AC power source are independent of the control power source of the device and the communication power source between the devices. Since it is possible to easily protect the device from the phase failure of the AC power supply, communication between devices can be performed, and it can be applied to applications such as an inverter device using a three-phase AC power supply.

Configuration block diagram of a control device for an air-conditioning apparatus according to Embodiment 1 of the present invention. Configuration block diagram of a control device for an air-conditioning apparatus according to Embodiment 2 of the present invention. Configuration block diagram of a conventional control device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Three-phase alternating current power supply 2 Control power supply part 2A Outdoor control power supply part 2B Indoor control power supply part 3 Compressor 4 Inverter control part 5 Communication power supply part 6 Equipment control part 6A Outdoor equipment control part 6B Indoor equipment control part 7 Three-phase rectification part 8 Smoothing capacitor 9 Voltage detection part 10 Inverter 11A Outdoor communication means 11B Indoor communication means 12 Three-phase normally open contact 13 Two-phase normally open contact 14 Current limiting part 15 Inverter control prohibition part

Claims (3)

Indoor control means for controlling the indoor unit, outdoor control means for controlling the outdoor unit, indoor communication means provided in the indoor unit, and communication power supply means for supplying power to the outdoor communication means provided in the outdoor unit. The communication power supply means is connected to a three-phase alternating current power supply via a power supply wiring, and the indoor control means and the outdoor control means are provided from predetermined two phases of the three-phase alternating current power supply. The communication power supply means receives power supply from one of the two predetermined phases and the remaining one phase other than the predetermined two phases, and between the indoor communication means and the outdoor communication means An air conditioner characterized in that the operation is prohibited or stopped when the communication is not established. A three-phase rectifying unit for smoothing a three-phase AC power source; an inverter for changing a DC voltage obtained by the three-phase rectifying unit to an arbitrary frequency; and a voltage detecting means for detecting the DC voltage. The air conditioner according to claim 1, wherein when the voltage is less than a predetermined voltage, the inverter unit is prohibited from operating. Three-phase normally open for opening and closing a three-phase AC power source to any one of the predetermined two phases and the remaining one phase other than the predetermined two phases via a current limiting unit for preventing inrush current Connect a two-phase normally open contact in parallel with the contact and close the two-phase normally open contact at the start of operation. If the DC voltage detected by the voltage detection means is less than the specified voltage, the inverter is prohibited from operating. The air conditioner according to claim 2, wherein the two-phase normally open contact is not closed.

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