JP2016180551A - Operation control device of air conditioner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that restart of a defrosting operation after recovery from power failure becomes wasteful when frost attached to a fin of an outdoor heat exchanger 14 is removed to a degree having no problem on an ordinary operation, though the defrosting operation is restarted in restart of the operation after the recovery from power failure, in a case where the operation before power failure is the defrosting operation.SOLUTION: An outdoor control portion 9 is provided with power failure recovery defrost necessity determination means 27 for determining whether defrosting is necessary or not in recovery from power failure, and power failure recovery control means 26 restarts an operation while switching to a heating operation without restarting the defrosting operation when the power failure recovery defrost necessity determination means 27 determines unnecessity of defrosting, even when power-failure memorizing means 25 memorizes the defrosting operation.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an air conditioner and relates to an operation control device that determines whether or not to perform a defrosting operation after recovery from a power failure.

  Conventionally, in the case of this kind of thing, when a power failure or the like occurs after starting operation, the operation state is stored in a nonvolatile storage device such as an EEPROM provided in the microcomputer and stored in this memory. Based on this, the operation is automatically resumed when the power is restored (Patent Document 1).

JP 2001-241740 A

However, in this conventional system, if the operation before the power outage was a defrosting operation, the operation is resumed when the operation is resumed, but the defrosting operation before the power outage is attached to the fins of the heat exchanger of the outdoor unit. When frosted frost is removed to such an extent that it does not interfere with normal operation, there has been a problem that resumption of defrosting operation after power failure recovery is useless.

In order to solve the above problems, the present invention forms a refrigeration circuit by connecting a compressor, a four-way valve for switching between a cooling cycle and a heating cycle, an indoor heat exchanger, an expansion valve, and an outdoor heat exchanger through refrigerant piping, By switching the four-way valve of the refrigeration circuit, an outdoor control unit that controls normal operation including cooling operation, heating operation, and defrosting operation is provided, and the outdoor control unit includes at least a heating operation immediately before a power failure at the time of a power failure. Power failure storage means for storing the type of operation including defrosting operation during heating operation, and power failure recovery control means for resuming operation with the type of normal operation stored in the power failure storage means at the time of power failure recovery In the air conditioner, the outdoor control unit is provided with a defrost necessity determination means at the time of power failure recovery that determines whether or not a defrosting operation is necessary after the power failure is restored, and the power failure recovery control means is excluded from the power failure storage means. Frost driving Even if you were 憶, when the power failure recovery during defrosting necessity determination means determines that unnecessary defrosting, and resumes the operation is switched to the heating operation without restarting the defrosting operation.

Further, the defrosting operation includes at least two types of a first defrosting operation performed by setting the refrigeration circuit to the cooling cycle and a second defrosting operation performed by setting the refrigeration circuit to the heating cycle, The power failure storage means discriminates and stores the type of the defrosting operation, and determines whether or not the defrosting operation is necessary according to the type of the defrosting operation stored in the power failure storage means. To change the standard.

In addition, the storage means at the time of power failure stores the defrosting operation continuation time of the time during which the defrosting operation before the power failure continued when the power failure occurred before the power failure. Even if the storage means at the time of power failure stores the defrosting operation, the determination means does not need to be defrosted when the defrosting operation duration is longer than the predetermined time. And the operation is restarted by switching to the heating operation without restarting the defrosting operation.

Further, the outdoor control unit includes an outdoor heat exchanger temperature sensor that detects a temperature of the refrigerant in the refrigeration circuit provided in a refrigerant pipe on an expansion valve side of the outdoor heat exchanger, and an intake side of the compressor. A suction temperature sensor for detecting the temperature of the refrigerant in the refrigeration circuit provided in the refrigerant pipe, and the defrosting necessity determination means at the time of power failure recovery is stored in the memory means at the time of power failure Even in this case, the defrosting operation before the power failure is the first defrosting operation in which the refrigeration circuit is used as the cooling cycle, and the heat exchanger temperature detected by the outdoor heat exchanger temperature sensor is a predetermined heat exchanger. When the refrigerant temperature is higher than the refrigerant temperature, or the defrosting operation before the power failure is a second defrosting operation in which the refrigeration circuit is used as the heating cycle, the suction temperature detected by the suction temperature sensor is higher than a predetermined suction temperature. If it is high, it is necessary to determine whether defrosting is required at the time of power failure recovery. In was determined to be unnecessary defrosting, to resume operation by switching to the heating operation without restarting the defrosting operation.

According to the present invention, when the defrost necessity determination means at the time of power failure recovery determines that the defrost operation is not required at the time of power failure recovery, the power failure control means switches to the heating operation without restarting the defrost operation. By restarting the operation, it is possible to prevent an unnecessary defrosting operation after the power failure is restored, and an efficient heating operation can be performed.

Further, whether or not the defrosting operation is necessary depends on the type of the defrosting operation including the first defrosting operation performed using the refrigeration circuit as a cooling cycle and the second defrosting operation performed using the refrigeration circuit as a heating cycle. By changing and setting the criterion for determining the defrosting operation, it is possible to prevent unnecessary defrosting operation after power failure recovery even if the defrosting necessity is different due to the type of defrosting operation. Heating operation can be performed.

Further, the defrosting operation continuation time that was performed before the power failure is determined for a predetermined time by determining whether or not the defrosting operation is necessary based on the defrosting operation continuation time by the defrosting necessity determining unit at the time of power failure recovery. If it is longer, the outdoor heat exchanger is sufficiently warmed by the defrosting operation before the power failure, so it is determined that the defrosting operation after the power failure is unnecessary, and the defrosting control means at the time of power failure recovery is the defrosting operation By switching to the heating operation without restarting the operation and restarting the operation, it is possible to prevent an unnecessary defrosting operation after the power failure recovery and to perform an efficient heating operation.

In addition, when the defrosting operation before the power failure is based on the cooling cycle, the heat detected by the heat exchanger temperature sensor after the power failure is recovered is determined by the defrosting necessity determination unit at the time of power failure recovery. When the defrosting operation after the power failure is determined based on the refrigerant temperature, and the defrosting operation before the power failure is based on the heating cycle, the necessary temperature after the power failure is detected at the suction temperature detected by the suction temperature sensor after the power failure is restored. By judging whether or not, the temperature of the refrigerant discharged from the outdoor heat exchanger after recovery from the power failure can be determined by the heat exchanger temperature sensor if the defrosting operation is in the cooling cycle before the power failure, and the defrosting in the heating cycle before the power failure. If the operation is detected by the suction temperature sensor, and the temperature of the refrigerant coming out of the outdoor heat exchanger after the power failure recovery is higher than a predetermined temperature, the refrigerant in the outdoor heat exchanger continues to be warm after the power failure recovery. Because there is no need for defrosting after a power failure The defrost control means at the time of power failure recovery can prevent unnecessary defrost operation after power failure recovery by switching to heating operation and restarting operation without restarting the defrost operation. Efficient heating operation can be performed.

Schematic explanatory diagram of one embodiment of the present invention Flow chart of the main part

Next, the structure of the air conditioner of embodiment of this invention is demonstrated based on drawing.
1 is an indoor unit of an air conditioner. A remote controller 2 installed on the indoor unit 1 side includes an air conditioner operation / stop switch, an indoor cooling / heating temperature setting switch, and an air conditioner operation stop. A switch 3 such as a timer setting switch capable of setting a time reservation, and a display unit 4 for displaying temperature and time on a liquid crystal panel or the like are provided.

Reference numeral 5 denotes an indoor control unit, which is sent from a room temperature sensor 6 located on the suction side of a ventilation path (not shown) provided in the indoor unit 1 when a heating temperature or an operation signal set by the remote controller 2 is input. Read the incoming room temperature and command the operating conditions. There are two operation commands issued by the indoor controller 5, one of which controls the indoor fan motor 7, and the other sends an operating condition signal to the outdoor controller 9 of the outdoor unit 8.
And the outdoor control part 9 controls normal operation including air_conditionaing | cooling operation, heating operation, and defrost operation based on the sent operating condition.

A fin tube type indoor heat exchanger 10 is provided on the downstream side of the room temperature sensor 6, and the air blown by the indoor fan 11 is rotated by the operation of the indoor fan motor 7, and the temperature is adjusted by the indoor heat exchanger 10. Is used to adjust the room temperature.

The outdoor unit 8 includes a compressor 12, a four-way valve 13 that switches between a cooling cycle and a heating cycle, an outdoor heat exchanger 14, and an expansion valve 15, and includes the indoor heat exchanger 10 of the indoor unit 1. A freezing circuit 16 is formed by communicating with piping, and a refrigerant such as R410 is circulated in the freezing circuit 16 to adjust the room temperature. The refrigerant that has flowed into the outdoor heat exchanger 14 that functions as a condenser is condensed by the outdoor air supplied by the outdoor blower fan 17.
In addition, a bypass pipe 18 that bypasses the refrigerant pipe that communicates the four-way valve 13 of the refrigeration circuit 16 and the indoor heat exchanger 10 and the refrigerant pipe that communicates the expansion valve 15 and the outdoor heat exchanger 14 of the refrigeration circuit 16 includes A two-way valve 19 for opening and closing the bypass pipe 18 is provided.

Reference numeral 20 denotes an outdoor heat exchanger temperature sensor that detects the temperature of the refrigerant in the refrigeration circuit 16 provided in the refrigerant pipe on the expansion valve 15 side of the outdoor heat exchanger 14, and is used as a material for judging the frost adhesion state. Reference numeral 21 denotes an outside air temperature sensor for detecting the outside air temperature, which is attached to the upstream side of the outdoor air blowing fan 17 through a ventilation path (not shown) in the outdoor unit 8 and detects the outside air temperature. Reference numeral 22 denotes a suction temperature sensor provided in the refrigerant pipe on the suction side of the compressor 12 and detects the temperature of the refrigerant in the refrigeration circuit 16.

The outdoor control unit 9 determines the operating frequency of the compressor 12 while obtaining information from the signal from the indoor control unit 5 and the value of the outside air temperature sensor 21, and controls the inverter. This inverter control is a direct current output from the converter. The compressor 12 is driven by converting the current into three-phase AC power.

Reference numeral 23 denotes frost formation detecting means for detecting frost formation on the outdoor heat exchanger 14 not only based on the heat-exchange refrigerant temperature and the outside air temperature but also on the refrigerant temperature in the refrigeration circuit 16 such as the suction temperature. Reference numeral 24 denotes a defrosting determination unit, in which the frosting detected by the frosting detection unit 23 and the state of the refrigeration circuit 16, the duration of the heating operation, the duration from the end of the previous frosting operation, or the outside air temperature are constant. The start of the defrosting operation or the determination of the release of the defrosting operation is performed according to the duration time after the temperature falls below the temperature.

25 is a storage means at the time of a power failure, and indicates the type of the normal operation before the power failure at the time of a power failure, and the defrosting operation continuation time when the defrosting operation is continued when the type of the normal operation is a defrosting operation. Remember. 26 is a control means at the time of power failure recovery, and restarts the operation with the normal operation type stored in the power failure storage means 25 at the time of power failure recovery. 27 is a defrost necessity determination means at the time of power failure recovery, and determines whether or not the defrost operation after the power failure recovery is necessary. When the power failure defrost necessity determination means 27 determines that the defrost operation is not required at the time of power failure recovery, the power failure recovery control means 26 switches to the heating operation and restarts the operation without restarting the defrost operation.

  And the defrost necessity determination means 27 at the time of power failure recovery is detected by the reference based on the defrosting operation continuation time before power failure stored in the power failure storage unit 25 or by the outdoor heat exchanger temperature sensor 20 after power failure recovery. The necessity of the defrosting operation is determined based on the reference based on the heat exchange refrigerant temperature or the suction temperature detected by the suction temperature sensor 22.

In the heating operation, as shown by the solid line arrow in FIG. 1, the two-way valve 19 is closed, and the compressor 12, the four-way valve 13, the indoor heat exchanger 10, the expansion valve 15, the outdoor heat exchanger 14, and the four-way valve 13. As the refrigerant circulates in the direction of, the outdoor heat exchanger 14 becomes low temperature, pumps heat from the outside air by the outdoor blower fan 17, the indoor heat exchanger 10 becomes high temperature, and warm air is blown indoors by the indoor blower fan 11. The room is heated by blowing it out. When the outside air temperature is low, frost is generated, and when this frost grows and covers the outdoor heat exchanger 14, heat exchange cannot be performed, so that a defrosting operation is required periodically.

The defrosting operation during the heating operation includes at least two types of defrosting operations, that is, a heating cycle defrosting operation and a cooling cycle defrosting operation, and the defrosting operation is appropriately performed according to the operation state.

First, in the heating cycle defrosting operation, by opening the two-way valve 19, a part of the high-temperature refrigerant is circulated from the compressor 12 to the outdoor heat exchanger 14 to be heated and attached to the outdoor heat exchanger 14. In the heating cycle defrosting operation, as shown by the solid line in FIG. 1, the compressor 12, the four-way valve 13, the indoor heat exchanger 10, the expansion valve 15, the outdoor heat exchanger 14, and the four-way valve 13 are used. And the two-way valve 19 in the open state, the refrigerant circulates in the direction of the compressor 12, the four-way valve 13, the two-way valve 19, the outdoor heat exchanger 14, and the four-way valve 13, so that The heat exchanger 10 becomes a high temperature, the indoor heat exchanger 10 becomes a high temperature, the indoor air blower fan 11 blows warm air into the room to heat the room, and a part of the high-temperature refrigerant is the outdoor heat exchanger 14. The frost that is circulated in the air and adheres to the surface of the outdoor heat exchanger 14 due to this heat. It is to the dregs heating cycle defrosting operation.

In the cooling cycle defrosting operation, the four-way valve 13 is switched, the two-way valve 19 is closed, and the high-temperature refrigerant is heated as it is flowing from the compressor 12 to the outdoor heat exchanger 14 to be heated. As shown by the broken line in FIG. 1, the compressor 12, the four-way valve 13, the outdoor heat exchanger 14, the expansion valve 15, and the indoor heat exchange are melted in the refrigerant. As the refrigerant circulates in the direction of the vessel 10 and the four-way valve 13, the indoor heat exchanger 10 becomes low temperature, but the drive of the indoor blower fan 11 is stopped so that the cool air does not flow into the room. Thus, the room temperature is not lowered, and the outdoor heat exchanger 14 is heated, and a cooling cycle defrosting operation is performed in which frost adhering to the surface of the outdoor heat exchanger 14 is melted by this heat.

In the cooling operation, as shown by the broken line in FIG. 1, the four-way valve 13 is switched, the two-way valve 19 is closed, and the compressor 12, the four-way valve 13, the outdoor heat exchanger 14, the expansion valve 15, the indoor heat As the refrigerant circulates in the direction of the exchanger 10 and the four-way valve 13, the indoor heat exchanger 10 becomes a low temperature, and the indoor air blowing fan 11 blows cold air into the room to cool the room.

As described above, in the cooling cycle defrosting operation, since the refrigerant heated at the compressor 12 flows directly to the outdoor heat exchanger 14, the frost adhering to the outdoor heat exchanger 14 is quickly melted, and the heat exchange refrigerant temperature Although the temperature of the refrigerant detected by the sensor 20 is also increased, the heating cycle defrosting operation bypasses a part of the refrigerant heated to high temperature by the compressor 12 and flows to the outdoor heat exchanger 14, so that it adheres to the outdoor heat exchanger 14. The frost melts slowly and the temperature of the refrigerant detected by the suction temperature sensor 22 does not increase, but the room can be heated at the same time.

As described above, since the time required for the defrosting operation and the place where the temperature of the refrigerant is detected are different depending on the type of the defrosting operation, the defrosting necessity determining means 27 at the time of power failure recovery is the defrosting operation after the power failure recovery. When determining whether or not it is necessary, it is necessary to change the determination of whether or not to defrost depending on the type of the defrosting operation before the power failure.

Next, the control when returning from a power failure will be described based on the flowchart of FIG.
When the power is restored from the power failure, it is confirmed whether the air conditioner stored in the power storage unit 25 at the time of the power failure is in the normal operation (S1). If it is not in operation (NO in S1), the operation is not resumed as it is, and the operation standby state is continued (S2). If it is in operation (S1 is YES), it is next checked whether the type of normal operation before the power failure was cooling operation (S3). When the cooling operation is performed before the power failure (YES in S3), the control means 26 at the time of power failure recovery restarts the cooling operation that is the type of the normal operation stored in the power failure storage means 25 at the time of power failure recovery (S4). . Further, when the operation before the power failure is other than the cooling operation (S3 is NO), it is next confirmed whether the operation before the power failure was a defrosting operation (S5). If the defrosting operation was not performed before the power failure (NO in S5), the control means 26 at the time of power failure recovery restarts the heating operation that is the type of the normal operation stored in the power failure storage means 25 at the time of power failure recovery (S6). .

If the operation before the power failure was a defrosting operation (S5 is YES), check if the defrosting operation before the power failure is a cooling cycle defrosting operation (S7), and if the operation before the power failure was a cooling cycle defrosting operation (S7 is YES), the defrost necessity determination means 27 at the time of power failure recovery indicates that the heat exchanger temperature detected by the outdoor heat exchanger temperature sensor 20 at the time of power failure recovery is less than a predetermined heat exchanger temperature (here, 8 ° C.). When either one of the conditions or the condition that the defrosting operation continuation time stored in the power failure storage means 25 is less than the first predetermined time (here, 5 minutes) is not satisfied (S8) NO), the defrost necessity determination means 27 at the time of power failure recovery is that the heat exchanger temperature detected by the heat exchanger temperature sensor 20 after the power failure recovery is 8 ° C. or higher, so the refrigerant in the outdoor heat exchanger 14 during the power failure is Warm state continues or at power failure storage means 25 Since the remembered defrosting operation duration is 5 minutes or longer, the defrosting operation time before the power failure is long and the outdoor heat exchanger 14 is sufficiently warmed. Therefore, it is determined that the defrosting operation is not necessary after the power failure is restored. Then, the power failure recovery control means 26 does not resume the defrosting operation but switches to the heating operation and resumes the operation (S6).

When both conditions are satisfied (S8 is YES), the power failure recovery control means 26 resumes the cooling cycle defrosting operation which is the type of the normal operation stored in the power failure storage means 25 at the time of power failure recovery (S9). .

When the defrosting operation before the power failure is not the cooling cycle defrosting operation (S7 is NO), the defrosting operation before the power failure is the heating cycle defrosting operation by the heating cycle, and therefore, different conditions from the cooling cycle defrosting operation. To determine whether or not defrosting is necessary. The defrost necessity determination means 27 at the time of power failure recovery is a condition that the suction temperature detected by the suction temperature sensor 22 at the time of power failure recovery is less than a predetermined suction temperature (here, 5 ° C.), or a power failure storage means 25. When the stored defrosting operation continuation time is less than the second predetermined time (here, 8 minutes), if any one of the conditions is not satisfied (S10 is NO), the defrosting necessity determining means at the time of power failure recovery 27, since the suction temperature detected by the suction temperature sensor 22 after the power failure recovery is 5 ° C. or higher, the refrigerant in the outdoor heat exchanger 14 after the power failure recovery remains warm or is stored in the power failure storage means 25. Since the defrosting operation continuation time is 8 minutes or longer, the defrosting operation time before the power failure is long, and the outdoor heat exchanger 14 is sufficiently warmed. Control means 26 at power failure recovery is defrosting By switching to the heating operation without restarting the rolling resume the operation (S6).

When both conditions are satisfied (S6 is YES), the power failure recovery control means 26 resumes the heating cycle defrosting operation, which is the type of the normal operation stored in the power failure storage means 25 at the time of power failure recovery (S11). .

Thus, when the defrost necessity determination means 27 at the time of power failure recovery determines that the defrost operation is not required at the time of power failure recovery, the power failure control means 26 switches to the heating operation without restarting the defrost operation. By resuming, it is possible to prevent unnecessary defrosting operation after power failure recovery and efficient heating operation can be performed.

Further, the defrosting necessity determination means 27 at the time of power failure recovery changes the defrosting operation duration time, the heat exchanger temperature or the suction temperature reference depending on the type of the defrosting operation, and thereby performs the defrosting operation. Even when the necessity of defrosting is different due to the difference in the types, it is possible to prevent unnecessary defrosting operation after power failure recovery and to perform efficient heating operation.

  In addition, this invention is not limited to embodiment, It does not prevent changing in the range which does not change a summary, For example, the 1st predetermined time of the defrost operation continuation time before a power failure is 5 minutes, The second predetermined time is 8 minutes, the predetermined heat-exchange refrigerant temperature at the time of power failure recovery is 8 ° C, and the predetermined suction temperature at the time of power failure recovery is 5 ° C, depending on the type of refrigerant and the specifications of the air conditioner. The time and temperature may be changed as appropriate.

DESCRIPTION OF SYMBOLS 1 Indoor unit 5 Indoor control part 8 Outdoor unit 9 Outdoor control part 10 Outdoor heat exchanger 12 Compressor 13 Four-way valve 14 Outdoor heat exchanger 15 Expansion valve 16 Refrigerating circuit 20 Outdoor heat exchanger temperature sensor 21 Outside temperature sensor 22 Intake temperature Sensor 23 Frost detection means 24 Defrost determination means 25 Memory means 26 at power failure recovery control means 27 Power failure recovery control means 27 Power failure recovery defrost necessity determination means

Claims (4)

A compressor, a four-way valve that switches between a cooling cycle and a heating cycle, an indoor heat exchanger, an expansion valve, and an outdoor heat exchanger are connected by refrigerant piping to form a refrigeration circuit, and by switching the four-way valve of the refrigeration circuit, An outdoor control unit that controls normal operation including cooling operation, heating operation, and defrosting operation is provided, and the outdoor control unit normally includes at least a heating operation immediately before a power failure during a power failure and a defrosting operation during the heating operation. In the air conditioner comprising: a power failure storage means for storing the operation type; and a power failure recovery control means for resuming the operation with the normal operation type stored in the power failure storage means when the power failure is recovered. The power failure defrosting necessity determining means for determining whether or not the defrosting operation is necessary after the power failure recovery is provided in the unit, and the power failure recovery control means is the case where the power failure storage means stores the defrosting operation. Even so, Serial When power failure recovery defrosting necessity determination means determines that unnecessary defrosting operation control device for air conditioner, characterized in that to resume the operation by switching to the heating operation without restarting the defrosting operation. The defrosting operation includes at least two types of a first defrosting operation performed using the refrigeration circuit as the cooling cycle and a second defrosting operation performed using the refrigeration circuit as the heating cycle. The storage means is a criterion for determining whether or not the defrosting operation is necessary according to the type of the defrosting operation stored by the storage means during the power failure, while the storage means during the power failure distinguishes and stores the type of the defrosting operation. The operation control device for an air conditioner according to claim 1, wherein: When the power failure storage means is the defrosting operation before the power failure, the defrosting operation continuation time of the time during which the defrosting operation before the power failure is continued is stored, and the defrosting necessity determination means at the time of power failure recovery is Even if the power storage unit stores the defrosting operation, if the defrosting operation continuation time is longer than a predetermined time, the defrosting necessity determining unit at the time of power failure recovery is not required to be defrosted. The operation control device for an air conditioner according to claim 1 or 2, wherein the operation control is performed by switching to the heating operation without restarting the defrosting operation and restarting the operation. An outdoor heat exchanger temperature sensor for detecting the temperature of the refrigerant in the refrigeration circuit provided in the refrigerant pipe on the expansion valve side of the outdoor heat exchanger, and the refrigerant pipe on the suction side of the compressor A suction temperature sensor for detecting the temperature of the refrigerant in the refrigeration circuit provided in the power supply circuit, and the defrost necessity determination means at the time of power failure recovery is a case where the storage means at the time of power failure stores the defrosting operation. Even if there is, the defrosting operation before the power failure is the first defrosting operation in which the refrigeration circuit is used as the cooling cycle, and the heat exchanger temperature detected by the outdoor heat exchanger temperature sensor is a predetermined heat exchanger temperature. Or when the defrosting operation before the power failure is the second defrosting operation in which the refrigeration circuit is used as the heating cycle, and the suction temperature detected by the suction temperature sensor is higher than a predetermined suction temperature. Is the defrosting necessity judgment at the time of power failure recovery In defrosting unnecessary and determined, the operation control device for air conditioner according to any one of claims 1 to 3, characterized in that to resume the operation by switching to the heating operation without restarting the defrosting operation.

Images