Air conditioner

Abstract

In the air conditioner of the present invention, two or more outdoor units and one or more indoor units are connected in parallel to the same refrigerant pipe, and the air conditioner includes a control unit, which determines the operation priority of the two or more outdoor units based on the operation capacity of the two or more outdoor units. The control unit changes the operation priority of the two or more outdoor units in the order of the operation capacity of the outdoor units from large to small and in the order of the operation capacity of the outdoor units from small to large at regular intervals.

Description

Technical Field

[0001] Embodiments relate to air conditioners. Background Art

[0002] In an air conditioner of a type in which a plurality of outdoor units are connected in parallel to the same refrigerant system, a technique for performing rotation control on an outdoor unit basis in order to make the accumulated operation time of each outdoor unit uniform is widely known.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Laid-Open No. 6-249529

[0006] Patent Document 2: Japanese Patent Application Publication No. 2003-166740 Summary of the invention

[0007] Technical problem to be solved by the invention

[0008] However, in the above technology, when one of the multiple outdoor units fails, the normal outdoor unit among the multiple outdoor units continues to operate immediately after the failure, so that the operation can continue. However, during this continuous operation, insufficient capacity occurs, which damages the air conditioning performance. Moreover, when all the outdoor units of the air conditioner stop and the air conditioner starts to operate again, if the operation priority of the outdoor unit with the failure is at the top, not only will the capacity be insufficient, but sometimes the operation cannot be started. In addition, if the operation priority of the outdoor unit that stops abnormally or detects an abnormality is at the top, the faulty outdoor unit will stop frequently during operation, or the capacity will be insufficient, which will damage the air conditioning performance. In this case, it will cause discomfort to the user.

[0009] The present embodiment provides an air conditioner capable of maintaining air conditioning performance even when a failure of an outdoor unit occurs in a plurality of outdoor units.

[0010] Technical means for solving technical problems

[0011] According to one embodiment, in an air conditioner, two or more outdoor units and one or more indoor units are connected in parallel to the same refrigerant pipe, and the air conditioner includes a control unit that determines the operation priority of the two or more outdoor units. The control unit changes the operation priority of the two or more outdoor units in the order of the operation capacity of the outdoor units from large to small and in the order of the operation capacity of the outdoor units from small to large at regular intervals based on the operation capacity of the two or more outdoor units. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 11 is a schematic diagram showing an example of the overall structure of an air conditioner.

[0013] Figure 2 is a flowchart showing an example of control.

[0014] Figure 3 is a flowchart showing an example of control. DETAILED DESCRIPTION

[0015] Below, the embodiments are described with reference to the accompanying drawings. In addition, the disclosure is only an example, and the present invention is not limited by the contents described in the following embodiments. Deformations that are easy for a person skilled in the art to think of are certainly included in the scope of the present disclosure. In order to make the description clearer, in the accompanying drawings, there are also cases where the size, shape, etc. of each part are changed relative to the actual embodiment and are represented in a schematic manner. Sometimes in multiple drawings, the same reference numerals are marked on the corresponding elements, and detailed descriptions are omitted.

[0016] (Implementation Method 1)

[0017] Hereinafter, the air conditioner in Embodiment 1 will be described with reference to the drawings.

[0018] Figure 1 1 is a schematic diagram showing an example of the overall structure of the air conditioner 1. Figure 1 In the description, as an example, the case where the air conditioner 1 includes four outdoor units and five indoor units is described, but the number of outdoor units and the number of indoor units are not limited to the above numbers.

[0019] like Figure 1 As shown, the air conditioner 1 includes an outdoor unit 2, an outdoor unit 3, an outdoor unit 4, and an outdoor unit 5, as four outdoor units arranged in parallel. In addition, the air conditioner 1 includes an indoor unit 6, an indoor unit 7, an indoor unit 8, an indoor unit 9, and an indoor unit A, as five indoor units arranged in parallel. The outdoor unit 2, the outdoor unit 3, the outdoor unit 4, the outdoor unit 5, the indoor unit 6, the indoor unit 7, the indoor unit 8, the indoor unit 9, and the indoor unit A are connected via an electrical wiring 100 and a refrigerant pipe 200.

[0020] The outdoor unit 2, the outdoor unit 3, the outdoor unit 4 and the outdoor unit 5 are main elements, and although not shown in the figure, they respectively include a compressor with a sensor for detecting the oil amount, a check valve, an oil separator, a four-way valve, a heat exchanger, an expansion valve, a liquid tank, an outdoor unit fan, a storage tank, an opening and closing valve, and a sensor for detecting the refrigerant flow rate flowing to the refrigerant piping 200.

[0021] The outdoor unit 2, the outdoor unit 3, the outdoor unit 4 and the outdoor unit 5 respectively include a control device 21, a control device 31, a control device 41 and a control device 51. Each of the control devices 21, 31, 41 and 51 includes a CPU, a memory, a storage device (non-volatile memory), an input / output circuit, a timer and the like, and performs a predetermined operation process. In addition, the control device 21, the control device 31, the control device 41 and the control device 51 are configured to be able to communicate via the electrical wiring 100 and to be able to send and receive information to each other. The detection values ​​detected by the sensors of the compressors of the outdoor units 2 to 5 and the sensors for detecting the refrigerant flow rate are output to the control devices 21, 31, 41 and 51.

[0022] Furthermore, the control device 21 of the outdoor unit 2 performs overall control of the air conditioner 1, such as calculation of the cumulative operation time, calculation of the operation capacity of each of the outdoor units 2 to 5, and change of the operation priority described later, based on the communication information received from the control devices 31, 41, and 51 of the other outdoor units 3, 4, and 5, respectively. In addition, in the present embodiment, the control device 21 is the control device that performs the overall function, but the control device 31, the control device 41, or the control device 51 may also perform the overall function. In addition, the control device that performs the overall function at a predetermined timing may be interchangeable among the control device 21, the control device 31, the control device 41, and the control device 51. In addition, a plurality of the control devices among the control device 21, the control device 31, the control device 41, and the control device 51 may also perform the above-mentioned overall function.

[0023] The indoor unit 6, the indoor unit 7, the indoor unit 8, the indoor unit 9, and the indoor unit A are respectively installed in buildings and structures, and adjust the air temperature of the installed spaces.

[0024] The indoor unit 6, the indoor unit 7, the indoor unit 8, the indoor unit 9 and the indoor unit A include a control device 61, a control device 71, a control device 81, a control device 91 and a control device A1, respectively. The control device 61, the control device 71, the control device 81, the control device 91 and the control device A1 communicate with the control device of the outdoor unit, in particular, the control device 21 which plays an overall role, via the electrical wiring 100.

[0025] In the air conditioner 1 constructed as described above, in order to condition the air in the room where the indoor units 6 to 9 and A are installed, the control device 21 selects an operating outdoor unit from among the outdoor units 2, 3, 4 and 5 based on the operation priority and activates it. Figure 21 is a flowchart showing an example of control performed by the control device 21 of the air conditioner 1. In the present embodiment, the CPU executes a program stored in a memory in the control device 21 to implement the following processing, but a circuit may be provided in the control device 21 to implement the following processing by the circuit.

[0026] like Figure 2 As shown, the control device 21 starts the operation of the air conditioner 1 at a predetermined timing (ST101). For example, the operation of the air conditioner 1 is started based on the timing reaching a predetermined time or an instruction to start the operation.

[0027] Next, the control device 21 sets the operation priority of each outdoor unit (from outdoor unit 2 to outdoor unit 5) in the order of operation capacity from large to small (ST102). For example, when the operation capacity of outdoor units 2 to 5 is outdoor unit 2> outdoor unit 3> outdoor unit 4> outdoor unit 5, the operation priority of outdoor unit 2 is priority P1, the operation priority of outdoor unit 3 is priority P2, the operation priority of outdoor unit 4 is priority P3, and the operation priority of outdoor unit 5 is priority P4. In the present embodiment, the priority order is P1>P2>P3>P4, where priority P1 has the highest priority and priority P4 has the lowest priority.

[0028] Next, the control device 21 determines whether there is an outdoor unit that has failed and stopped from the outdoor unit 2 to the outdoor unit 5 (ST103). The outdoor unit that has failed and stopped cannot operate and is a stopped outdoor unit. When it is determined that there is an outdoor unit that has failed and stopped (ST103 is "Yes"), the control device 21 determines whether all the outdoor units 5 from all the outdoor units 2 have failed and stopped (ST104). When it is determined that all the outdoor units 2 to the outdoor units 5 have failed and stopped (ST104 is "Yes"), the control device 21 stops the operation (ST117) and ends the operation.

[0029] In addition, when it is determined that not all of the outdoor units 2 to 5 have failed and stopped (ST104 is "No"), the control device 21 determines whether there is an outdoor unit that has failed and stopped (ST105). When it is determined that there is an outdoor unit that has failed and stopped (ST105 is "Yes"), the control device 21 fixes the operation priority of the outdoor unit that has failed and stopped to a lower level based on the lowest level (ST106). For example, when it is determined that the outdoor unit 3 has failed and stopped, in the case that the outdoor unit 4 has failed and stopped, the outdoor unit 4 is fixed to the priority level P4, and therefore, the priority level of the outdoor unit 3 is fixed to P3 based on the lowest level P4 (in other words, one priority higher than the lowest level).

[0030] When it is determined that there is no outdoor unit that has failed and stopped (ST105 is "No"), the control device 21 fixes the operation priority of the outdoor unit that has failed and stopped to the lowest level (ST107). For example, when it is determined that the outdoor unit 3 has failed and stopped, if there is no outdoor unit that has failed and stopped, the priority of the outdoor unit 3 is fixed to the lowest priority level P4.

[0031] After the processing of step ST106 or the processing of step ST107, the control device 21 determines whether there is an outdoor unit with an abnormality detected (ST108). The abnormality of the outdoor unit is, for example, a situation where insufficient oil is detected in the compressor or insufficient refrigerant flows to the refrigerant piping 200, that is, a state where the operation can be performed but the required performance may not be achieved. These can be detected based on information received by the control device 21 from another control device 31 to 51 via the electrical wiring 100. When it is determined that there is an outdoor unit with an abnormality detected (ST108 is "yes"), the control device 21 changes the operating priority of the outdoor unit with the abnormality detected to a lower level based on the lowest level (ST109). For example, when the outdoor unit 3 has failed and stopped and the outdoor unit 3 is fixed to the priority P4, when an abnormality is detected in the outdoor unit 5 this time, the operating priority of the outdoor unit 5 is changed to the priority P3.

[0032] When the processing of step ST109 is completed, or when it is determined in step ST108 that no abnormal outdoor unit is detected (ST108 is "No"), the control device 21 moves the operating priority of the lower outdoor unit up by one position when the outdoor unit with a lower operating priority is the upper one (ST112).

[0033] For example, when the operation priorities are set such that outdoor unit 2 is at priority P1, outdoor unit 3 is at priority P2, outdoor unit 4 is at priority P3, and outdoor unit 5 is at priority P4, when outdoor unit 3 fails and stops, the operation priority of outdoor unit 3 is fixed at priority P4, and the operation priorities of outdoor unit 4 and outdoor unit 5, which have lower operation priorities than outdoor unit 3, are moved up one level to priority P2 and P3, respectively. In addition, the operation priority of outdoor unit 2, which has a higher operation priority than outdoor unit 3, is maintained at priority P1 and is not changed from priority P1.

[0034] On the other hand, when it is determined that there is no outdoor unit that has failed and stopped (ST103 is "No"), the control device 21 determines whether there is an outdoor unit that has detected an abnormality (ST110). As described above, the outdoor unit that has detected an abnormality is an outdoor unit that has stopped due to reasons other than normal stop such as thermal disconnection when receiving an operation stop signal, such as when insufficient oil is detected in the compressor and insufficient refrigerant flows to the refrigerant piping 200. When it is determined that there is an outdoor unit that has detected an abnormality (ST110 is "Yes"), the control device 21 changes the operation priority of the outdoor unit that has detected an abnormality to a lower priority based on the lowest priority (ST111). For example, when it is determined that an outdoor unit 3 is abnormally detected this time, if there is no outdoor unit that has failed and stopped, the priority of the outdoor unit 3 is fixed to the lowest priority P4, and if there is one outdoor unit that has failed and stopped, it is changed to the priority P3 based on the lowest priority.

[0035] Thus, when the processing of step ST112 is completed or it is determined that no abnormal outdoor unit is detected in the processing of step ST110 (ST110 is "No"), the control device 21 determines whether the cumulative operation time has passed the T time (ST113). Here, the T time is a predetermined time, and if an example is given, the T time is set to 30 hours. When it is determined that the cumulative operation time has passed the T time (ST113 is "Yes"), the control device 21 reverses the operation priority (the order from large to small and the order from small to large of the operation capacity) except for the outdoor unit that has failed and stopped or detected an abnormality (ST114). For example, in the case where there is no outdoor unit that has failed and stopped and no outdoor unit that has abnormality and stopped, when the outdoor unit 2 has priority P1, the outdoor unit 3 has priority P2, the outdoor unit 4 has priority P3, and the outdoor unit 5 has priority P4, the operation priority of the outdoor unit 2 is changed to priority P4, the operation priority of the outdoor unit 3 is changed to priority P3, the operation priority of the outdoor unit 4 is changed to priority P2, and the operation priority of the outdoor unit 5 is changed to priority P1. In addition, in the case where the outdoor unit 5 fails and stops, the outdoor unit 5 is fixed to priority P4 and is excluded from the change of the operation priority. When the outdoor unit 2 has priority P1, the outdoor unit 3 has priority P2, and the outdoor unit 4 has priority P3, the outdoor unit 2 is changed to priority P3, the outdoor unit 3 is changed to priority P2, and the outdoor unit 4 is changed to priority P1. In addition, when the control device 21 determines that the accumulated operation time has not passed the T time (ST113 is "No"), the process returns to the process of step ST103.

[0036] After the processing of step ST114 is completed, the control device 21 resets the accumulated operation time (ST115). Then, the control device 21 determines whether the operation stop signal is received (ST116). Based on the timing of reaching the specified time and the instruction to stop the operation, the operation stop signal is sent to the control device 21. In the case where it is determined that the operation stop signal is received (ST116 is "Yes"), the control device 21 stops the operation of the air conditioner 1 (ST117) and ends the operation. On the other hand, in the case where it is determined by the control device 21 that the operation stop signal is not received (ST116 is "No"), the processing returns to the processing of step ST103.

[0037] As described above, except for the outdoor unit that has failed and stopped, or except for the outdoor unit that has failed and stopped and the outdoor unit that has detected an abnormality, the control device 21 reverses the operation priority corresponding to the capacity of the outdoor unit every time the accumulated operation time passes T time (i.e., a period of time), thereby making the operation time of the outdoor units 2 to 5 uniform. In addition, since the control device 21 fixes the operation priority of the outdoor unit that has failed and stopped at the lowest level, the air conditioner 1 can perform normal operation corresponding to the user's request through other outdoor units, thereby performing air conditioning without causing inconvenience to the user. In addition, the control device 21 makes the outdoor unit that has detected an abnormality at the lowest level or one level higher than the lowest level, thereby reducing the operation frequency of the outdoor unit that has detected an abnormality. As a result, the air conditioner 1 can suppress the occurrence of the situation where the outdoor unit that has detected an abnormality stops, thereby performing air conditioning without causing inconvenience to the user.

[0038] (Implementation Method 2)

[0039] The present embodiment is different from the above-mentioned embodiment 1 in that the present embodiment is configured to change the setting of the operation priority of the outdoor unit included in the air conditioner 1. Therefore, the process of changing the setting of the operation priority will be described in detail. In addition, the same reference numerals are given to the same structures as those in the above-mentioned embodiment 1, and detailed description thereof will be omitted.

[0040] Figure 3 1 is a flowchart showing an example of control performed by the control device 21 of the air conditioner 1 .

[0041] like Figure 3 As shown, the control device 21 starts the operation of the air conditioner 1 at a predetermined timing (ST201). For example, starting the operation of the air conditioner 1 based on the timing reaching a predetermined time or an instruction to start the operation is the same as the processing of the above-mentioned step ST101.

[0042] Next, the control device 21 sets the operation priority of each outdoor unit (from outdoor unit 2 to outdoor unit 5) (ST202). For example, the control device 21 sets the priority of outdoor unit 2 to P1, the priority of outdoor unit 3 to P2, the priority of outdoor unit 4 to P3, and the priority of outdoor unit 5 to P4.

[0043] Next, the control device 21 executes the processing from step ST203 to step ST213. The processing from step ST203 to step ST213 is the same as the processing from step ST103 to step ST113 described above (see: Figure 2 ). Therefore, the description of the processing of step ST203 or step ST213 is omitted.

[0044] In step ST213, when it is determined that the accumulated operation time has passed T time (ST213 is "Yes"), the control device 21 changes the operation priority of the outdoor unit with the highest operation priority to the lowest among the outdoor units in which no fault or abnormality is detected (ST214). When the processing of step ST214 is completed, the control device 21 moves up one step the operation priority of the outdoor units except the one with the highest operation priority among the outdoor units in which no fault or abnormality is detected (ST115).

[0045] For example, when outdoor unit 3 fails and stops, and the operation priority is set to outdoor unit 2 with priority P1, outdoor unit 3 with priority P4, outdoor unit 4 with priority P2, and outdoor unit 5 with priority P3, the operation priority of outdoor unit 2, which is the highest in the operation priority, is changed to priority P3, which is the lowest in the outdoor units that have not failed and stopped. In addition, outdoor unit 4 is changed from priority P2 to priority P1, and outdoor unit 5 is changed from priority P3 to priority P2, and the priorities are moved up by one level. As a result, the priorities of outdoor units 2, 4, and 5 are changed except for priority P4 of outdoor unit 3.

[0046] Next, the control device 21 resets the accumulated operating time (ST216), determines whether an operation stop signal is received (ST217), and if an operation stop signal is received (ST217 is "yes"), stops the operation of the air conditioner 1 (ST218), and ends the processing. If it is determined that no operation low signal is received, returns to the processing of step ST203, which is the same as the above-mentioned embodiment 1.

[0047] As described above, except for the outdoor unit that has failed and stopped, or except for the outdoor unit that has failed and stopped and the outdoor unit in which an abnormality is detected, the control device 21 changes the operation priority, so that in the air conditioner 1, other outdoor units can operate normally and perform air conditioning without causing inconvenience to the user.

[0048] Several embodiments of the present invention have been described above, but these embodiments are presented only as examples and are not intended to limit the scope of the invention. These new embodiments can be implemented in various other ways, and various omissions, substitutions, and changes can be made without departing from the gist of the invention. These embodiments and their variations are all included in the scope and gist of the invention, and are also included in the invention described in the patent claims and their equivalents.

[0049] Description of symbols

[0050] 1…air conditioner, 2-5…outdoor unit, 6-9, A…indoor unit, 21-51…control device, 61-91, A1…control device, 100…electrical wiring, 200…refrigerant piping, P1-P4…priority.

Claims

1. An air conditioner, wherein two or more outdoor units and one or more indoor units are connected in parallel to the same refrigerant pipe, the air conditioner being characterized in that: The controller includes a control unit that determines the operation priority of the two or more outdoor units based on the operation capabilities of the two or more outdoor units. The control unit changes the operation priorities of the two or more outdoor units in the order of the operation capacity of the outdoor units from large to small or in the order of the operation capacity of the outdoor units from small to large at regular intervals. When one of the two or more outdoor units stops due to a failure, the control unit fixes the operation priority of the outdoor unit to the lowest level. When an abnormality is detected in an outdoor unit other than the outdoor unit whose operation priority is fixed to the lowest level, the control unit sets the operation priority of the outdoor unit in which the abnormality is detected to a level higher than the lowest level by one priority level, The failure is a state in which the system cannot operate. The exception is a state where the system can run but may not be able to perform the required performance.

2. The air conditioner according to claim 1, characterized in that The outdoor unit includes a compressor, When the oil shortage of the compressor is detected, the control unit detects an abnormality of the outdoor unit including the compressor.

3. The air conditioner according to claim 2, characterized in that When it is detected that the refrigerant flowing through the refrigerant pipe is insufficient and when the outdoor unit in which the refrigerant of the compressor is less than a predetermined value is detected, the control unit detects abnormality of the detected outdoor unit.

4. The air conditioner according to claim 1, wherein: The control unit determines the operation priority levels except for the outdoor unit having the lowest operation priority level that has the failure and has stopped and the outdoor unit having the operation priority level that is one priority level higher than the lowest operation priority level that has detected the abnormality and has stopped.

5. An air conditioner, wherein two or more outdoor units and one or more indoor units are connected in parallel to the same refrigerant pipe, the air conditioner being characterized in that: The controller includes a control unit that determines the operation priority of the two or more outdoor units based on the operation capabilities of the two or more outdoor units. The control unit changes the operation priorities of the two or more outdoor units in the order of the operation capacity of the outdoor units from large to small or in the order of the operation capacity of the outdoor units from small to large at regular intervals. The control unit sets the operation priority of the outdoor unit that has detected an abnormality and stopped the outdoor unit to the lowest level, In a case where an outdoor unit other than the outdoor unit that has detected the abnormality and stopped stops due to a fault, the control unit fixes the operation priority of the outdoor unit that has stopped due to the fault at the lowest level, and moves the operation priority of the outdoor unit that has detected the abnormality and stopped up by one level from the lowest level, The failure is a state in which the system cannot operate. The exception is a state where the system can run but may not be able to perform the required performance.

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