JP2012127616A - Air conditioning system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioning system capable of properly controlling equipment protection while improving energy saving performance.SOLUTION: In the air conditioning system, a centralized control apparatus 51 issues a thinning control command to a plurality of air conditioners 1, to selectively stop the plurality of air conditioners 1. The plurality of air conditioners 1 respectively perform equipment protection control. The thinning control command is invalidated when the thinning control command is issued during execution of the equipment protection control or when equipment protection control command is issued during execution of thinning control.

Description

  The present invention relates to an air conditioning system.

  Conventionally, an air conditioning system including a plurality of air conditioners (outdoor units) that air-condition a single air-conditioned space (for example, a large space such as a concert hall), and a centralized control device that controls each of the air conditioners. Is known (for example, Patent Document 1). Such an air conditioning system includes an electric heat pump (hereinafter also referred to as EHP) type air conditioner using an electric motor as a drive source, and a gas heat pump (hereinafter also referred to as GHP) type air conditioner using a gas engine, and The air conditioning balance between the EHP and GHP air conditioners is controlled by a centralized control device (integrated air conditioning controller) according to their characteristics (for example, cost), so that the entire air conditioning system is optimally controlled. To do.

JP 2007-187342 A

  By the way, irrespective of the system (EHP type, GHP type), a single air-conditioned space is also air-conditioned by a plurality of air conditioners (outdoor units) controlled by a central control device. For example, for the purpose of improving energy saving and reducing the operation time of each outdoor unit of each air conditioner, a control (hereinafter referred to as “thinning control”) that stops a part of the operating air conditioners (outdoor units) with a central control device. It is also proposed to do this.

  However, for example, in an outdoor unit of an arbitrary air conditioner, air conditioning is being performed during a four-way valve switching control (hereinafter also referred to as “equipment protection control”) that switches the refrigerant flow path of the refrigeration cycle between cooling and heating. When the machine thinning control is performed, when the corresponding air conditioner is stopped, the device protection control is interrupted without being completed. In this case, when the operation of the corresponding air conditioner is resumed, it is unavoidable to restart from one of the interrupted device protection controls.

  The objective of this invention is providing the air conditioning system which can implement apparatus protection control suitably, aiming at the improvement of energy saving property.

  In order to solve the above-described problems, the invention described in claim 1 includes a plurality of outdoor units that perform air conditioning of an air-conditioned space, and a central control device that controls each of the outdoor units. In the air conditioning system for selectively stopping the plurality of outdoor units by issuing a thinning control instruction to the plurality of outdoor units, the equipment protection is provided when the equipment protection control instruction is provided in the plurality of outdoor units. The device protection control means for performing control, and when the thinning control instruction is issued during the execution of the device protection control, or when the device protection control instruction is issued during the execution of the thinning control, the thinning control instruction is invalidated The gist of the invention is that it includes invalid means.

  According to this configuration, the plurality of outdoor units are selectively stopped by issuing a thinning control instruction to the plurality of outdoor units from the centralized control device. Thereby, for example, by reducing the number of the outdoor units to be operated, the energy saving property can be improved. On the other hand, when the thinning control instruction is issued while the device protection control means is executing the equipment protection control, the invalidation means invalidates the thinning control instruction. Therefore, the device protection control of the corresponding outdoor unit that should originally have been stopped can be suitably performed. Further, when the device protection control instruction is issued during the thinning control, the invalidation means invalidates the thinning control instruction. Therefore, the execution of the thinning control can be stopped, and the device protection control can be suitably executed (started).

  According to a second aspect of the present invention, in the air conditioning system according to the first aspect, the device protection control includes a defrost control for performing defrosting of the outdoor unit and a refrigerant of the refrigeration cycle between the cooling and heating operations. The gist is that it is at least one of the switching control of the four-way valve for switching the flow path.

  According to this configuration, for example, when the decimation control instruction is given during the execution of the defrosting control, the decimation control instruction is invalidated by the invalidating means, which should originally have been stopped. Occurrence of problems due to insufficient defrosting of the outdoor unit can be suppressed. Further, when the device protection control instruction related to the defrost control is given during the execution of the thinning control, the thinning control instruction is invalidated by the invalidating unit. Therefore, the execution of the thinning control can be stopped and the defrosting control can be suitably performed (started). Alternatively, when the decimation control instruction is issued during the switching control of the four-way valve, the decimation control instruction is invalidated by the invalidating means, and the corresponding outdoor unit that was originally supposed to be stopped Occurrence of problems due to insufficient switching of the four-way valve can be suppressed. In addition, when the device protection control instruction related to the switching control of the four-way valve is issued during the thinning control, the invalidation means invalidates the thinning control instruction. Therefore, the execution of the thinning control can be stopped, and the switching control of the four-way valve can be suitably performed (started).

  In the present invention, it is possible to provide an air conditioning system capable of suitably implementing device protection control while improving energy saving.

The schematic block diagram which shows one Embodiment of this invention. The schematic block diagram which shows the air conditioner of the embodiment. The flowchart which shows the control aspect of the embodiment. Explanatory drawing which shows the conditions of execution / non-execution of thinning-out control.

  An embodiment of the present invention will be described with reference to FIG. As shown in FIG. 1, the air conditioning system includes a plurality (5 in this embodiment) of GHP air conditioners 1 that air-condition a single air-conditioned space S. In each air conditioner 1, the outdoor unit 10 is installed on the outside (outdoor) of the air-conditioned space S, and a plurality of indoor units 30 are installed on the inside (indoor) of the air-conditioned space S. The plurality of outdoor units 10 (control devices) are electrically connected to each other so that various types of information can be shared among them. The plurality of outdoor units 10 normally air-condition the air-conditioned space S in cooperation with all operations (normal control).

  A plurality of outdoor units 10 (control devices) are connected to a management device (for example, a computer) 50 of a management center that collectively manages a plurality of customers via a central control device 51 mainly composed of, for example, a microcomputer. Electrically connected. Based on various preset conditions, the management device 50 selectively transmits a thinning control instruction to the plurality of outdoor units 10 via the centralized control device 51 in order to promote energy saving. This thinning control instruction includes information for specifying the outdoor unit 10 to be operated and the outdoor unit 10 to be stopped, that is, information for changing the number of the outdoor units 10 to be operated, among all the outdoor units 10. Each outdoor unit 10 that has received the thinning control instruction normally performs (continues or starts) its operation according to this, or stops its operation.

  Basically, by reducing the number of outdoor units 10 to be operated, energy saving can be achieved as the entire air conditioning system. Therefore, the number of outdoor units 10 to be operated is set to be greatly reduced as the degree of target energy saving (hereinafter also referred to as “energy saving rate”) at the time of performing the thinning control is larger. Specifically, when the plurality of outdoor units 10 are distinguished from the outdoor units 10A, 10B, 10C, 10D, and 10E from the upper side to the lower side in the figure, normal control for operating all the outdoor units 10A to 10E is performed. On the other hand, four units of the outdoor units 10A, 10B, 10D, and 10E are operated in the thinning control with the energy saving rate increased by one rank, and three of the outdoor units 10A, 10C, and 10E are operated in the thinning control with the energy saving rate increased by one rank. In the thinning-out control with the energy saving rate increased by one rank, two outdoor units 10B and 10D are operated.

  As shown in FIG. 2, each outdoor unit 10 is provided with a gas engine 11 that generates rotational power by burning fuel gas (for example, propane gas, natural gas, etc.) supplied from a gas company. A compressor 12 that is driven to rotate by the gas engine 11 and compresses the refrigerant with the rotation is installed. The compressor 12 compresses the refrigerant (gas refrigerant) sucked from the suction pipe 12a and sends the refrigerant to the four-way valve 14 connected to the discharge pipe 12b via the refrigerant pipe 13a.

  The four-way valve 14 is connected to the outdoor unit heat exchanger 15 through the refrigerant pipe 13b, and is connected to each indoor unit 30 (indoor unit heat exchanger 31) of the air conditioner 1 through the refrigerant pipe 13d. Yes. The four-way valve 14 is connected to an accumulator 18 through a refrigerant pipe 13f, and the accumulator 18 is connected to the suction pipe 12a of the compressor 12 through a refrigerant pipe 13g.

  The outdoor unit heat exchanger 15 functions as a refrigerant condenser during cooling operation and functions as a refrigerant evaporator during heating operation. The outdoor unit heat exchanger 15 is connected to the indoor unit 30 (indoor unit electronic expansion valve 32) via a refrigerant pipe 13h. )It is connected to the. A check valve 21 that allows the refrigerant to flow toward the indoor unit 30 is disposed in the refrigerant pipe 13h, and an electronic expansion valve 22 is disposed in parallel with the check valve 21.

  The indoor unit heat exchanger 31 installed in each indoor unit 30 is connected to the refrigerant pipe 13d and to the indoor unit electronic expansion valve 32. The indoor unit electronic expansion valve 32 is connected to the refrigerant pipe 13h. The indoor unit heat exchanger 31 functions as a refrigerant evaporator during cooling operation and functions as a refrigerant condenser during heating operation.

Next, the flow of the refrigerant in the air conditioner 1 will be described. In addition, the flow of the refrigerant | coolant at the time of each operation | movement of cooling and heating is represented by the solid line arrow and the broken line arrow.
First, during the cooling operation, the refrigerant that has exited the discharge pipe 12b of the compressor 12 passes through the four-way valve 14, and is then guided to the outdoor unit heat exchanger 15 that functions as a condenser. In the outdoor unit heat exchanger 15, the refrigerant is deprived of heat by outdoor air (outside air), and condensed and liquefied. Thereafter, the refrigerant is depressurized in the indoor unit electronic expansion valve 32 of each indoor unit 30, and in the indoor unit heat exchanger 31 functioning as an evaporator, the heat of the room air is taken and vaporized. Thereafter, the refrigerant returns to the suction pipe 12 a of the compressor 12 through the four-way valve 14 and the accumulator 18. Through the above process, the room is cooled.

  On the other hand, during the heating operation, the refrigerant that has exited the discharge pipe 12 b of the compressor 12 passes through the four-way valve 14 and is then guided to the indoor unit 30. The refrigerant releases heat into the indoor air in the indoor unit heat exchanger 31 functioning as a condenser, and condenses and liquefies. Thereafter, the refrigerant decompressed by the indoor unit electronic expansion valve 32 is guided to the outdoor unit heat exchanger 15. The refrigerant absorbs and vaporizes the heat of the outdoor air in the outdoor unit heat exchanger 15 that functions as an evaporator. Thereafter, the refrigerant from the outdoor unit heat exchanger 15 through the four-way valve 14 returns to the suction pipe 12 a of the compressor 12 through the accumulator 18. Through the above process, the room is heated.

Next, the electrical configuration of the present embodiment will be described.
As shown in FIG. 1, the outdoor unit 10 is provided with a control device 41 that drives and controls the gas engine 11, the four-way valve 14, and the like. This control device 41 is mainly composed of a microcomputer, and is electrically connected to a temperature sensor 42 provided in the refrigerant pipe 13h on the downstream side of the outdoor unit heat exchanger 15 during the cooling operation. This temperature sensor 42 detects the piping temperature (surface temperature) T of the refrigerant discharged from the outdoor unit heat exchanger 15 during the defrosting operation.

  The control device 41 outputs a switching control instruction as an equipment protection control instruction and switches the refrigerant flow path of the refrigeration cycle to switch the refrigerant flow path of the refrigeration cycle when the cooling / heating operation is switched, for example, at the time of a season change. Switching control (equipment protection control means). It should be noted that the switching control of the four-way valve 14 cannot actually be completed only by electrical switching, and a certain level of refrigerant pressure (refrigerant flow rate / flow velocity), that is, the rotational speed of the gas engine 11 is essential. Yes.

  In addition, when the pipe temperature T becomes lower than a predetermined temperature during the heating operation, the control device 41 defrosts as a device protection control instruction to remove frost attached to the outdoor unit 10 (the outdoor unit heat exchanger 15 or the like). A control instruction is issued to perform defrosting control as device protection control (device protection control means). Specifically, the four-way valve 14 is once switched so as to correspond to the cooling operation, and the defrosting operation is performed in which the outdoor unit heat exchanger 15 functions as a condenser. Even in this case, a certain level of refrigerant pressure (refrigerant flow rate / flow velocity), that is, the rotational speed of the gas engine 11 is essential for switching the four-way valve 14 between cooling and heating operations. Not too long.

  On the other hand, each indoor unit 30 is provided with a control device 46 that drives and controls the indoor unit electronic expansion valve 32 and the like. The control device 46 is mainly composed of a microcomputer, and is electrically connected to the control device 41 of the outdoor unit 10. The control device 41 controls the control devices 46 of the plurality of indoor units 30 connected to the outdoor unit 10 mounted thereon, and controls the arrangement, the number, and the like of the indoor units 30 to be operated.

  The outdoor unit 10 is electrically connected to the centralized control device 51 in the control device 41, and the above-described thinning control instruction is transmitted through the centralized control device 51. The control device 41 that has received the thinning control instruction basically performs driving (continuing) of the gas engine 11 when the information of the thinning control instruction indicates the execution (continuation, start) of the operation of the outdoor unit 10 on which the thinning control instruction is mounted. On the other hand, when the stop of the operation of the outdoor unit 10 is indicated, the driving of the gas engine 11 is stopped.

  Next, a description will be given of a selection control mode in which thinning control is performed / not performed (continuation of normal control) by the control device 41 of any outdoor unit 10. As shown in FIG. 3, for example, when the process shifts to this routine by a scheduled interruption every predetermined time, it is determined in S (step) 1 whether there is a thinning-out control instruction. When it is determined that there is a thinning control instruction, the process proceeds to S2 and it is determined whether or not the “A condition” is not established. As shown in FIG. 4, this “A condition” is composed of a logical sum during defrosting control of at least one outdoor unit 10 and switching control of the four-way valve 14. “A condition” is not established when neither frost control nor switching control of the four-way valve 14 is being performed, and “A condition” is established when at least one outdoor unit 10 is performing any control.

  If it is determined in S2 that the “A condition” is not established, the process proceeds to S3, where thinning control is performed in accordance with the thinning control instruction. On the other hand, if it is determined in S2 that the “A condition” is satisfied, the process proceeds to S4 and the thinning control is not performed (the thinning control instruction is invalidated: invalid means).

Next, the operation of this embodiment will be described.
First, it is assumed that the above-described normal control is performed by the control devices 41 of all the outdoor units 10. At this time, when the thinning control instruction is received via the centralized control device 51, if the “A condition” is not established, the control device 41 is mounted to realize the energy saving rate according to the thinning control instruction. The driving of the gas engine 11 of the outdoor unit 10 is performed (continuation, restart), or the driving of the gas engine 11 of the outdoor unit 10 is stopped. As a result, the number of gas engines 11 being driven is reduced, and energy saving during air conditioning is realized as the entire system.

  On the other hand, if the defrosting control is being performed by at least one outdoor unit 10 (between the start determination of the defrost control is satisfied and the end determination is satisfied) and the “A condition” is satisfied, all the corresponding cases are satisfied. The thinning-out control instruction is invalidated until the defrosting control is completed in the outdoor unit 10. Thereby, the defrosting control (including the switching control of the four-way valve 14 from the heating operation to the cooling operation) of the corresponding outdoor unit 10 that should originally have been stopped can be completed, and the defrosting is insufficient. The occurrence of defects is suppressed. Then, with the completion of the defrosting control, the switching of the four-way valve 14 is not required for the next activation (starting) of the outdoor unit 10 once stopped, so that the outdoor unit 10 is normally activated.

  In addition, if switching control of the four-way valve 14 is being performed by at least one outdoor unit 10 and the “A condition” is satisfied, similarly, thinning is performed until switching control of the four-way valve 14 is completed in all corresponding outdoor units 10. The control instruction is invalidated. Thereby, the switching control of the four-way valve 14 of the corresponding outdoor unit 10 that should originally have been stopped can be completed, and the occurrence of problems due to insufficient switching of the four-way valve 14 is suppressed. Then, with the completion of the switching control of the four-way valve 14, the switching control of the four-way valve 14 is unnecessary at the next activation (starting) of the outdoor unit 10 once stopped, so that the outdoor unit 10 starts normally. Is called.

  In addition, when the defrost control or the switching control of the four-way valve 14 is started during the thinning control according to the thinning control instruction, or when those start conditions are satisfied, the execution of the thinning control is temporarily stopped, Control is started.

As described above in detail, according to the present embodiment, the following effects can be obtained.
(1) In this embodiment, the plurality of outdoor units 10 are selectively stopped by instructing the thinning control to the plurality of outdoor units 10 (air conditioner 1) by the centralized control device 51. Thereby, energy saving property can be improved by reducing the number of outdoor units 10 to operate, for example. On the other hand, when there is a thinning control instruction during the execution of device protection control (defrost control or switching control of the four-way valve 14), the thinning control instruction is invalidated. Therefore, the device protection control of the corresponding outdoor unit 10 that should originally have been stopped can be suitably performed. In addition, when there is a device protection control instruction (defrost control instruction, switching control instruction) during the thinning control, the thinning control instruction is invalidated. Therefore, the execution of the thinning control can be stopped, and the device protection control (defrost control or switching control of the four-way valve 14) can be suitably performed (started).

  (2) In this embodiment, for example, when a decimation control instruction is issued during the defrosting control, the decimation control instruction is invalidated so that the corresponding outdoor unit 10 that should have been stopped originally is stopped. Occurrence of problems due to insufficient defrosting can be suppressed. Further, when there is a defrosting control instruction during execution of the thinning control, the thinning control instruction is invalidated. Therefore, the implementation of the defrosting control can be stopped and the defrosting control can be suitably performed (started).

  Alternatively, when a decimation control instruction is issued during the switching control of the four-way valve 14, the corresponding outdoor unit 10 (air conditioner 1) that should have been originally stopped by invalidating the decimation control instruction. ) Can be prevented from occurring due to insufficient switching of the four-way valve 14. Further, when there is a switching control instruction during the execution of the thinning control, the thinning control instruction is invalidated. Accordingly, it is possible to preferably perform (start) the switching control of the four-way valve 14 by stopping the thinning control.

In addition, you may change the said embodiment as follows.
In the above embodiment, only when the air conditioner 1 scheduled to be stopped is in the process of device protection control (defrost control or switching control of the four-way valve 14) when there is a thinning control instruction, The thinning control instruction may be invalidated.

  -In the said embodiment, when the thinning-out control instruction | indication is given, when the air conditioner 1 scheduled to be stopped is performing apparatus protection control (defrost control or switching control of the four-way valve 14), the said air The thinning control instruction may be invalidated only by the harmony machine 1.

In the embodiment, when the thinning control instruction is invalidated, it is more preferable to transmit (reply) that effect from the control device 41 to the centralized control device 51.
In the above-described embodiment, in the thinning-out control, for example, the south side outdoor unit 10 may be operated slightly in winter and the north side outdoor unit 10 may be operated more. Further, in the outdoor unit 10 (air conditioner 1) in operation, for example, in the winter season, among the plurality of indoor units 30 connected thereto, the south side indoor unit 30 is operated in a small amount, and the north side indoor unit 30 is increased. You may make it drive.

  In the embodiment described above, the centralized control device 51 may mainly perform selection control of execution / non-execution (continuation of normal control) of the thinning-out control. Further, the functions of the management device 50 related to the thinning control instruction may be integrated into the central control device 51.

  In the embodiment, the invalidation of the thinning control instruction when switching from the normal control to the thinning control has been described. On the other hand, even if the thinning control is being performed, the thinning control instruction may be similarly invalidated when switching from the thinning control of one rank to the thinning control of another rank.

  In the embodiment, the air conditioning system may be composed of a plurality of EHP air conditioners, or a combination of an EHP air conditioner and a GHP air conditioner.

In the above embodiment, the plurality of indoor units 30 are separated from the outdoor units 10 other than the connected outdoor units 10, but may be connected to the plurality of outdoor units 10.
-In the said embodiment, if the number of the outdoor units 10 (air conditioner 1) which air-conditions the to-be-conditioned space S is plural, it is arbitrary. Further, the number of indoor units 30 connected to each outdoor unit 10 is arbitrary.

  -The air conditioning system which controls the air conditioning of several air-conditioned space with several outdoor unit may be sufficient.

  DESCRIPTION OF SYMBOLS S ... Air-conditioned space, 1 ... Air conditioner, 10, 10A-10E ... Outdoor unit, 14 ... Four-way valve, 51 ... Central control apparatus, 41 ... Control apparatus (apparatus protection control means, invalid means).

Claims (2)

A plurality of outdoor units that air-condition the air-conditioned space, and a centralized control device that controls each of the outdoor units, and the centralized control device instructs the plurality of outdoor units to perform thinning-out control. In the air conditioning system that selectively stops the machine,
A device protection control means arranged in the plurality of outdoor units and performing device protection control when there is a device protection control instruction;
An invalidation unit that invalidates the thinning-out control instruction when the thinning-out control instruction is issued during the implementation of the equipment protection control or when the equipment protection control instruction is issued during the execution of the thinning-out control; Air conditioning system characterized by The air conditioning system according to claim 1,
The device protection control is at least one of defrost control for performing defrosting of the outdoor unit and switching control of a four-way valve for switching a refrigerant flow path of a refrigeration cycle between cooling and heating operations. Harmony system.

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