CN115031348A - Control system and method of central air conditioner - Google Patents

Abstract

The invention provides a control system and a method of a central air conditioner, belonging to the field of central air conditioner control, wherein the control system comprises: the system comprises a main network, a standby network, a main exchanger, a standby exchanger, a low-temperature group control subsystem, a medium-temperature group control subsystem, a cooling water group control subsystem and a standby control subsystem; each control subsystem is connected to a main network through a main switch and is connected to a standby network through a standby switch; when the main network and the main switch are not in fault, the three main control subsystems carry out signal transmission through the main network and the standby control subsystem; when the main network or the main switch breaks down, the three main control subsystems carry out signal transmission with the standby control subsystem through the standby network; when the low-temperature group control subsystem or the medium-temperature group control subsystem or the cooling water group control subsystem is abnormal, the standby control subsystem controls corresponding bottom equipment, the cost of the central air-conditioning control system is reduced, and the real-time performance of control is improved.

Description

Control system and method of central air conditioner

Technical Field

The invention relates to the field of central air conditioner control, in particular to a control system and a control method of a central air conditioner.

Background

The single point failure is a component in the single-layer control system of the central air conditioner, which fails to operate the whole system when one point fails, in other words, the single point failure is a failure of the whole system.

The current single-point failure solution is to use an additional decision layer to solve dual-master or dual-backup operation, and when a failure system is switched to an available backup system, if a hot backup purpose is to be achieved, the switching needs to be completed before the backup system executes a next cycle task. However, due to the logic calculation requirement, the data related to the execution of the current task is usually in the memory of the computer, and the synchronization of the real-time data needs to be completed before the next cycle of the task, which can be regarded as the judgment basis of the hot standby system.

The dual-computer single-active structure belongs to cold standby, and has the problems of time delay because the switching can be completed only when the dual-computer single-active structure fails and needs to be started, and the dual-computer single-active structure can be started only when the dual-computer single-active structure is restarted due to a failure and needs manual intervention. However, the dual-active structure simultaneously acquires input, simultaneously executes logic, and simultaneously calculates output, but because the input acquires two parts, the problem of counting out one source cannot be guaranteed, the output of the dual-active structure also generates inconsistent results with errors, so that the output result needs to be subjected to additional decision making, as shown in fig. 1, although hot standby is available, a new single-point failure problem is introduced, and the cost of system deployment is increased.

In view of the above, a new control system is needed to reduce the system cost and improve the real-time performance of the control.

Disclosure of Invention

The invention aims to provide a control system and a control method of a central air conditioner, which can reduce the cost of the control system of the central air conditioner and improve the real-time performance of the control.

In order to achieve the purpose, the invention provides the following scheme:

a control system of a central air conditioner for controlling a low temperature device, a medium temperature device and a cooling water device of the central air conditioner, the control system of the central air conditioner comprising: the system comprises a main network, a standby network, a main exchanger, a standby exchanger, a low-temperature group control subsystem, a medium-temperature group control subsystem, a cooling water group control subsystem and a standby control subsystem;

the low-temperature group control subsystem, the medium-temperature group control subsystem, the cooling water group control subsystem and the standby control subsystem are all connected into the main network through the main switch;

the low-temperature group control subsystem, the medium-temperature group control subsystem, the cooling water group control subsystem and the standby control subsystem are all connected to the standby network through the standby switch;

when the main network and the main exchanger do not break down, the low-temperature group control subsystem, the medium-temperature group control subsystem and the cooling water group control subsystem carry out signal transmission with the standby control subsystem through the main network and the main exchanger;

when the main network or the main exchanger breaks down, the low-temperature group control subsystem, the medium-temperature group control subsystem and the cooling water group control subsystem carry out signal transmission with the standby control subsystem through the standby network and the standby exchanger;

the low-temperature group control subsystem is connected with the low-temperature equipment and is used for controlling the low-temperature equipment;

the medium-temperature group control subsystem is connected with the medium-temperature equipment and is used for controlling the medium-temperature equipment;

the cooling water group control subsystem is connected with the cooling water equipment and is used for controlling the cooling water equipment;

the standby control subsystem is used for controlling the low-temperature equipment or the medium-temperature equipment or the cooling water equipment when the low-temperature group control subsystem or the medium-temperature group control subsystem or the cooling water group control subsystem is abnormal.

Optionally, the cryo-group control subsystem comprises:

the low-temperature data interaction unit is connected with the standby control subsystem and is used for carrying out signal transmission with the standby control subsystem through the main network and the main switch when the main network and the main switch are not in fault, and carrying out signal transmission with the standby control subsystem through the standby network and the standby switch when the main network or the main switch is in fault so as to carry out heartbeat state judgment and role state judgment; the heartbeat state is online at the opposite end or offline at the opposite end; the role state is activated or standby;

the low-temperature data acquisition unit is used for acquiring the operation data of the low-temperature equipment;

and the low-temperature main control unit is connected with the low-temperature data interaction unit, the low-temperature data acquisition unit and the low-temperature equipment and is used for generating a low-temperature main control signal according to the operation data of the low-temperature equipment when the heartbeat state is an opposite end offline state and the role state is activated so as to control the operation of the low-temperature equipment.

Optionally, the backup control subsystem comprises:

the low-temperature group backup control unit is connected with the low-temperature equipment and used for transmitting signals with the low-temperature group control subsystem through the main network and the main switch when the main network and the main switch are not in fault, transmitting signals with the low-temperature group control subsystem through the standby network and the standby switch when the main network or the main switch is in fault so as to judge the heartbeat state, judge the role state, synchronize real-time data and synchronize historical records, collecting the operation data of the low-temperature equipment when the heartbeat state is offline at the opposite end and the role state is activated, and generating a low-temperature backup control signal according to the operation data of the low-temperature equipment so as to control the operation of the low-temperature equipment;

the medium-temperature group standby control unit is connected with the medium-temperature equipment and is used for transmitting signals with the medium-temperature group control subsystem through the main network and the main switch when the main network and the main switch are not in fault, transmitting signals with the medium-temperature group control subsystem through the standby network and the standby switch when the main network or the main switch is in fault so as to judge the heartbeat state, judge the role state, synchronize real-time data and synchronize historical records, collecting the operation data of the medium-temperature equipment when the heartbeat state is off-line at the opposite end and the role state is activated, and generating a medium-temperature standby control signal according to the operation data of the medium-temperature equipment so as to control the operation of the medium-temperature equipment;

the cooling water crowd is equipped with the control unit, with the cooling water equipment is connected, is used for the main network reaches when the main switch does not break down, through the main network reaches the main switch with cooling water crowd control subsystem carries out signal transmission when main network or main switch break down, through the standby network with the standby switch with cooling water crowd control subsystem carries out signal transmission to carry out heartbeat state judgement, role state judgement, real-time data synchronization and historical record synchronization, and when the heartbeat state is the off-line of opposite end and the role state is the activation, gather the operational data of cooling water equipment, according to the operational data production cooling water of cooling water equipment is equipped with control signal, in order to control the operation of cooling water equipment.

Optionally, the cryo-group control subsystem has two ethernet ports: a first network port and a second network port;

the low-temperature group control subsystem is connected with the main switch through a first network port, and the low-temperature group control subsystem is connected with the standby switch through a second network port.

In order to achieve the purpose, the invention also provides the following scheme:

a control method of a central air conditioner is applied to the control system of the central air conditioner, and comprises the following steps:

the low-temperature group control subsystem, the medium-temperature group control subsystem, the cooling water group control subsystem and the standby control subsystem are connected into a main network through a main switch;

the low-temperature group control subsystem, the medium-temperature group control subsystem, the cooling water group control subsystem and the standby control subsystem are connected into a standby network through a standby switch;

judging whether the main network and the main switch operate normally or not;

if the main network and the main exchanger operate normally, the low-temperature group control subsystem, the medium-temperature group control subsystem and the cooling water group control subsystem perform signal transmission with the standby control subsystem through the main network and the main exchanger;

if the main network or the main exchanger fails, the low-temperature group control subsystem, the medium-temperature group control subsystem and the cooling water group control subsystem perform signal transmission with the standby control subsystem through the standby network and the standby exchanger;

judging whether the low-temperature group control subsystem normally operates, if so, controlling low-temperature equipment through the low-temperature group control subsystem, and otherwise, controlling the low-temperature equipment through the standby control subsystem;

judging whether the medium-temperature group control subsystem normally operates, if so, controlling medium-temperature equipment through the medium-temperature group control subsystem, and otherwise, controlling the medium-temperature equipment through the standby control subsystem;

and judging whether the cooling water cluster control subsystem normally operates, if so, controlling cooling water equipment through the cooling water cluster control subsystem, and otherwise, controlling the cooling water equipment through the standby control subsystem.

Optionally, the determining whether the low-temperature group control subsystem operates normally, if so, controlling the low-temperature equipment through the low-temperature group control subsystem, otherwise, controlling the low-temperature equipment through the standby control subsystem specifically includes:

the method comprises the steps that self-checking is carried out through a low-temperature group control subsystem, if the state of the low-temperature group control subsystem is abnormal, the standby control subsystem is used for collecting the operation data of low-temperature equipment and generating a low-temperature standby control signal according to the operation data of the low-temperature equipment so as to control the operation of the low-temperature equipment;

if the state of the low-temperature group control subsystem is normal, judging the heartbeat state through the signal transmission of the low-temperature group control subsystem and the standby control subsystem; the heartbeat state is online at the opposite end or offline at the opposite end;

when the heartbeat state is off-line at the opposite end, the role state of the low-temperature group control subsystem is activated;

when the heartbeat state is on-line at the opposite end, determining the role state of the low-temperature group control subsystem according to the starting time of the low-temperature group control subsystem and the starting time of the standby control subsystem; the role state is activated or standby;

when the role state is activated, acquiring the operation data of the low-temperature equipment through a low-temperature group control subsystem, and generating a low-temperature main control signal according to the operation data of the low-temperature equipment so as to control the operation of the low-temperature equipment;

and when the role state is standby, acquiring the operation data of the low-temperature equipment through the standby control subsystem, and generating a low-temperature standby control signal according to the operation data of the low-temperature equipment so as to control the operation of the low-temperature equipment.

Optionally, the determining a heartbeat state through signal transmission between the low-temperature group control subsystem and the standby control subsystem specifically includes:

sending a heartbeat request to the standby control subsystem through the low-temperature group control subsystem;

if the heartbeat response of the standby control subsystem is not received by the continuous set times, the heartbeat state of the low-temperature group control subsystem is off-line at the opposite end;

and if the heartbeat response of the standby control subsystem is received, the heartbeat state of the low-temperature group control subsystem is that the opposite terminal is on-line.

Optionally, the determining the role state of the low-temperature group control subsystem according to the start time of the low-temperature group control subsystem and the start time of the standby control subsystem specifically includes:

if the starting time of the low-temperature group control subsystem is earlier than that of the standby control subsystem, the role state of the low-temperature group control subsystem is activated;

if the starting time of the low-temperature group control subsystem is later than that of the standby control subsystem, the role state of the low-temperature group control subsystem is standby;

and if the starting time of the low-temperature group control subsystem is equal to that of the standby control subsystem, restarting the low-temperature group control subsystem, wherein the role state of the low-temperature group control subsystem is standby.

Optionally, determining whether the low-temperature group control subsystem operates normally, if so, controlling the low-temperature equipment through the low-temperature group control subsystem, otherwise, controlling the low-temperature equipment through the standby control subsystem further includes:

when the standby control subsystem controls the operation of the low-temperature equipment, the standby control subsystem sends the operation data of the low-temperature equipment to the low-temperature group control subsystem;

when the low-temperature group control subsystem controls the operation of the low-temperature equipment, the operation data of the low-temperature equipment is sent to the standby control subsystem through the low-temperature group control subsystem.

According to the specific embodiment provided by the invention, the invention discloses the following technical effects: the low-temperature group control subsystem, the medium-temperature group control subsystem, the cooling water group control subsystem and the standby control subsystem are all connected into the main network through the main switch, the low-temperature group control subsystem, the medium-temperature group control subsystem, the cooling water group control subsystem and the standby control subsystem are all connected into the standby network through the standby switch, the main network and the standby network are completely independent, an additional decision layer is not needed to be introduced, a new single-point fault cannot be introduced, three sets of control mechanisms are only needed to be designed in the standby control subsystem, the hardware cost is reduced, and the real-time performance of control of related equipment of the central air conditioner is improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without inventive exercise.

FIG. 1 is a schematic diagram of a conventional dual-active structure;

FIG. 2 is a schematic structural diagram of a control system of a central air conditioner according to the present invention;

FIG. 3 is a flowchart illustrating a method for controlling a central air conditioner according to the present invention;

fig. 4 is a schematic diagram of a heartbeat status detection process.

Description of the symbols:

the system comprises a low-temperature group control subsystem-1, a medium-temperature group control subsystem-2, a cooling water group control subsystem-3, a standby control subsystem-4, a main exchanger-5, a standby exchanger-6 and communication lines-7.1, 7.2, 7.3, 7.4, 8.1, 8.2, 8.3 and 8.4.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Generally, a large and medium-sized central air conditioning control and management system can be generally divided into four-layer structures of a device layer, a control layer, a management layer and a network layer. And for the control layer, the management layer and the like, the single-point fault problem can occur, and in order to solve the single-point fault problem of each layer, the application provides the control system and the control method of the central air conditioner, an independent dual-network dual-system redundancy design method and an N +1 hot standby mechanism are adopted, an additional decision layer is not required to be deployed, the redundancy design is directly carried out on the layer, the hardware cost is reduced, and the real-time performance of the control of relevant equipment of the central air conditioner is improved.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.

As shown in fig. 2, the control system of the central air conditioner of the present invention comprises: the system comprises a main network, a standby network, a main exchanger 5, a standby exchanger 6, a low-temperature group control subsystem 1, a medium-temperature group control subsystem 2, a cooling water group control subsystem 3 and a standby control subsystem 4.

The low-temperature group control subsystem 1, the medium-temperature group control subsystem 2, the cooling water group control subsystem 3 and the standby control subsystem 4 are all connected to the main network through the main switch 5. In fig. 2, the low-temperature group control subsystem 1, the medium-temperature group control subsystem 2, the cooling water group control subsystem 3, and the standby control subsystem 4 are connected to the main switch 5 through communication lines 7.1, 7.2, 7.3, and 7.4, respectively, to form a main network. The low-temperature group control subsystem 1, the medium-temperature group control subsystem 2, the cooling water group control subsystem 3 and the standby control subsystem 4 are respectively connected with the standby switch 6 through communication lines 8.1, 8.2, 8.3 and 8.4 to form a standby network.

The low-temperature group control subsystem 1, the medium-temperature group control subsystem 2, the cooling water group control subsystem 3 and the standby control subsystem 4 are all connected to the standby network through the standby switch 6.

Specifically, the low-temperature group control subsystem 1 has two ethernet ports: a first network port and a second network port. The low-temperature group control subsystem 1 is connected with the main switch 5 through a first internet access, and the low-temperature group control subsystem 1 is connected with the standby switch 6 through a second internet access.

The medium-temperature group control subsystem 2 has two ethernet ports: a third port and a fourth port. The medium-temperature group control subsystem 2 is connected with the main switch 5 through a third network port, and the medium-temperature group control subsystem 2 is connected with the standby switch 6 through a fourth network port.

The cooling water group control subsystem 3 has two ethernet ports: a fifth network port and a sixth network port. The cooling water crowd control subsystem 3 through the fifth net gape with the main exchange 5 is connected, the cooling water crowd control subsystem 3 through the sixth net gape with the standby exchange 6 is connected.

The standby control subsystem 4 has two ethernet ports: a seventh port and an eighth port. The standby control subsystem 4 is connected with the main switch 5 through a seventh internet access, and the standby control subsystem 4 is connected with the standby switch 6 through an eighth internet access.

When the main network and the main exchanger 5 do not have faults, the low-temperature group control subsystem 1, the medium-temperature group control subsystem 2 and the cooling water group control subsystem 3 carry out signal transmission with the standby control subsystem 4 through the main network and the main exchanger 5.

When the main network or the main exchanger 5 fails, the low-temperature group control subsystem 1, the medium-temperature group control subsystem 2 and the cooling water group control subsystem 3 perform signal transmission with the standby control subsystem 4 through the standby network and the standby exchanger 6. After the main network or the main exchanger is repaired, the main network or the main exchanger can be manually switched to carry out signal transmission, namely, the low-temperature group control subsystem, the medium-temperature group control subsystem and the cooling water group control subsystem are manually arranged to carry out signal transmission through the main network, the main exchanger and the standby control subsystem.

The low-temperature group control subsystem 1 is connected with the low-temperature equipment, and the low-temperature group control subsystem 1 is used for controlling the low-temperature equipment.

The medium-temperature group control subsystem 2 is connected with the medium-temperature equipment, and the medium-temperature group control subsystem 2 is used for controlling the medium-temperature equipment.

The cooling water group control subsystem 3 is connected with the cooling water equipment, and the cooling water group control subsystem 3 is used for controlling the cooling water equipment.

The standby control subsystem 4 is used for controlling the low-temperature equipment or the medium-temperature equipment or the cooling water equipment when the low-temperature group control subsystem 1 or the medium-temperature group control subsystem 2 or the cooling water group control subsystem 3 is abnormal.

In this embodiment, the network ports of the main exchange 5 and the standby exchange 6 are at least 7 ports. The primary network and the backup network are physically completely isolated so that there is no interaction between the primary network and the backup network. The industrial personal computer where each control subsystem is located is at least required by double network ports, and the network ports are physically isolated, so that no interaction is generated. Thus forming two completely isolated, secure two-channel links. The mutually isolated double-channel links ensure that the links are smooth after a single-point fault occurs. Under the condition of single-point failure, whether the opposite end is normal can be known without introducing an additional decision layer, so that the condition of double main or double standby cannot occur.

The dual channel link functions as: a) the low-temperature group control subsystem, the medium-temperature group control subsystem and the cooling water group control subsystem are communicated with the equipment layer downwards and the management layer upwards; b) and the low-temperature group control subsystem, the medium-temperature group control subsystem and the cooling water group control subsystem are in communication interaction with the standby control subsystem.

Specifically, the control logic and the internal structure of the low-temperature group control subsystem 1, the medium-temperature group control subsystem 2, and the cooling water group control subsystem 3 are the same, and this embodiment only takes the low-temperature group control subsystem 1 as an example for detailed description, and the specific control logic and the internal structure of the medium-temperature group control subsystem 2 and the cooling water group control subsystem 3 are not described herein again.

The low-temperature group control subsystem 1 is provided with low-temperature group control software and an industrial personal computer. The low-temperature group control software is deployed in the industrial personal computer, and the operation of the low-temperature equipment is controlled through the industrial personal computer.

The cryo-group control subsystem 1 comprises: the system comprises a low-temperature data interaction unit, a low-temperature data acquisition unit and a low-temperature main control unit.

Wherein, low temperature data interaction unit with backup control subsystem 4 is connected, low temperature data interaction unit is used for the main network reaches when 5 do not break down of main exchange, through the main network reaches main exchange 5 with backup control subsystem 4 carries out signal transmission when main network or 5 break down of main exchange, through the backup network with backup exchange 6 with backup control subsystem 4 carries out signal transmission to carry out heartbeat state judgement and role state judgement.

The low-temperature data acquisition unit is used for acquiring the operation data of the low-temperature equipment.

The low-temperature main control unit is connected with the data interaction unit, the low-temperature data acquisition unit and the low-temperature equipment, and is used for generating a low-temperature main control signal according to the operation data of the low-temperature equipment when the heartbeat state is an opposite-end offline state and the role state is activated so as to control the operation of the low-temperature equipment.

Furthermore, the standby control subsystem 4 is provided with three sets of control software and an industrial personal computer. The standby control subsystem 4 includes: a low-temperature group backup control unit, a medium-temperature group backup control unit and a cooling water group backup control unit.

The low-temperature group backup control unit, the medium-temperature group backup control unit and the cooling water group backup control unit are all independent control software. The low temperature crowd is equipped with the control unit with low temperature equipment connects, and low temperature crowd is equipped with the control unit and is used for main network reaches when main switch 5 does not break down, through main network reaches main switch 5 with low temperature crowd control subsystem 1 carries out signal transmission when main network or main switch 5 break down, through standby network with standby switch 6 with low temperature crowd control subsystem 1 carries out signal transmission to carry out heartbeat state judgement, role state judgement, real-time data synchronization and historical record synchronization, and when the heartbeat state is off-line and the role state is for the activation for the opposite terminal, gather the operational data of low temperature equipment, according to the operational data production low temperature of low temperature equipment is equipped with control signal, in order to control the operation of low temperature equipment.

Medium temperature crowd is equipped with the control unit with medium temperature equipment connects, and medium temperature crowd is equipped with the control unit and is used for the main network reaches when main exchange 5 does not break down, through the main network reaches main exchange 5 with medium temperature crowd control subsystem 2 carries out signal transmission when main network or main exchange 5 break down, through standby network with standby exchange 6 with medium temperature crowd control subsystem 2 carries out signal transmission to carry out heartbeat state judgement, role state judgement, real-time data synchronization and historical record are synchronous, and when the heartbeat state is opposite terminal off-line and the role state is for the activation, gather the operational data of medium temperature equipment, according to medium temperature equipment's operational data produces medium temperature and is equipped with control signal, with control the operation of medium temperature equipment.

The cooling water crowd is equipped with the control unit with the cooling water equipment is connected, and the cooling water crowd is equipped with the control unit and is used for the main network reaches when the main exchange 5 does not break down, through the main network reaches main exchange 5 with cooling water crowd control subsystem 3 carries out signal transmission when main network or main exchange 5 break down, through the standby network with standby exchange 6 with cooling water crowd control subsystem 3 carries out signal transmission to carry out heartbeat state judgement, role state judgement, real-time data synchronization and historical record are synchronous, and when the heartbeat state is opposite terminal off-line and the role state is for the activation, gather the operational data of cooling water equipment, according to the operational data production cooling water of cooling water equipment is equipped with control signal, in order to control the operation of cooling water equipment.

Specifically, the low-temperature group backup control unit, the medium-temperature group backup control unit and the cooling water group backup control unit are three sets of control software, and are all deployed in an industrial personal computer of the standby control subsystem 4. The control logics and internal structures of the low-temperature group control unit, the medium-temperature group control unit and the cooling water group control unit are the same as those of the low-temperature group control subsystem, the medium-temperature group control subsystem and the cooling water group control subsystem, and are not described again here.

In order to better understand the scheme of the invention, the following description is further combined with specific examples.

In this embodiment, the control systems are respectively: a low-temperature group control subsystem 1, a medium-temperature group control subsystem 2, a cooling water group control subsystem 3 and a standby control subsystem 4. The industrial personal computer where each control subsystem is located needs at least 2 Ethernet ports, one Ethernet port of the device where each control subsystem is located is connected with the main switch 5 through a main network, and the other Ethernet port is connected with the standby switch 6 through a standby network.

Each control main system consists of 1 set of control software, an industrial personal computer where 1 piece of software is located, a combination main network and a standby network. And the 1 standby control subsystem 4 consists of 3 sets of control software, industrial personal computer software where 1 set of software is located, and a main network and a standby network. The 4 sets of software have the function of a hot standby mechanism and are responsible for completing hot standby switching operation of the software.

A first network port of the low-temperature group control subsystem 1 is connected into a main network through a main switch 5, and a second network port is connected into a standby network through a standby switch 6. And a third network port of the medium-temperature group control subsystem 2 is connected into the main network through a main switch 5, and a fourth network port is connected into the standby network through a standby switch 6. And a fifth network port of the cooling water group control subsystem 3 is connected into the main network through a main exchanger 5, and a sixth network port is connected into the standby network through a standby exchanger 6. The seventh network port of the standby control subsystem 4 is connected to the main network through the main switch 5, and the eighth network port is connected to the standby network through the standby switch 6.

And the devices of the three control subsystems are connected with the main network. And connecting the device where the main control subsystem is located with the standby network. All addresses belong to different Ethernet ports, and isolation among networks is ensured.

Further, the master switch is connected up to the master switch of the control-management network and the standby switch is connected up to the standby switch of the control-management network, ensuring isolation and interworking with the management network. The main exchanger and the standby exchanger are connected with the equipment layer network downwards respectively. The network of the equipment layer is usually organized according to different preparation processes, and the network organization forms are various and are not the key point of the invention, so that the description is not excessive. The requirement for the device layer network, when the device layer network is connected to the main switch and the standby switch, needs to ensure that the ethernet networking is necessary and at least 2 ethernet links are provided for connection.

The invention has 3 sets of main control subsystems (low temperature group control subsystem, medium temperature group control subsystem, cooling water group control subsystem) and 1 set of standby control subsystem, wherein each 1 set of main control subsystem is composed of 1 set of control software, an industrial personal computer where 1 set of software is located, and a main network and a standby network are combined. And the standby control subsystem consists of 3 sets of control software, an industrial personal computer where 1 set of software is located, and a main network and a standby network. It can be seen that the number of hardware facilities (industrial personal computer and network) constituting the system is equal, and the number of software in the standby control subsystem is 3, i.e. the hardware facilities are N +1, and the software is N + N. When the independent dual-network dual-system structure is adopted, the hardware is N +1, and compared with a conventional method of redundancy of software and hardware, the hardware cost can be effectively controlled. And N is the number of main control subsystems.

The master-slave backup mechanism of N +1 is universal in structure and has very high universality. And the main network and the standby network, the main control subsystem and the standby control subsystem, and the corresponding devices thereof are physically isolated, so that the security is extremely high. Each part is composed of independent systems, and each part is of a conventional deployment structure, so that the deployment difficulty is low, and the maintenance cost is low.

As shown in fig. 3, the method for controlling a central air conditioner according to the present invention comprises:

s1: and the low-temperature group control subsystem, the medium-temperature group control subsystem, the cooling water group control subsystem and the standby control subsystem are connected into the main network through the main switch.

S2: and the low-temperature group control subsystem, the medium-temperature group control subsystem, the cooling water group control subsystem and the standby control subsystem are connected into a standby network through a standby switch.

S3: and judging whether the main network and the main switch operate normally or not.

S4: and if the main network and the main exchanger normally operate, the low-temperature group control subsystem, the medium-temperature group control subsystem and the cooling water group control subsystem perform signal transmission through the main network, the main exchanger and the standby control subsystem.

S5: and if the main network or the main exchanger fails, the low-temperature group control subsystem, the medium-temperature group control subsystem and the cooling water group control subsystem perform signal transmission with the standby control subsystem through the standby network and the standby exchanger.

S6: and judging whether the low-temperature group control subsystem normally operates, if so, controlling low-temperature equipment through the low-temperature group control subsystem, and otherwise, controlling the low-temperature equipment through the standby control subsystem.

S7: and judging whether the medium-temperature group control subsystem normally operates, if so, controlling medium-temperature equipment through the medium-temperature group control subsystem, and otherwise, controlling the medium-temperature equipment through the standby control subsystem.

S8: and judging whether the cooling water group control subsystem normally operates, if so, controlling cooling water equipment through the cooling water group control subsystem, and otherwise, controlling the cooling water equipment through the standby control subsystem.

Further, the specific execution logics of the steps S6-S8 are the same, and the difference is only that the low-temperature group control subsystem, the medium-temperature group control subsystem, and the cooling water group control subsystem respectively control the low-temperature equipment, the medium-temperature equipment, and the cooling water equipment, and the specific execution process of the standby control subsystem is also similar, so the present invention specifically introduces the control logics of the low-temperature group control subsystem only as an example, and the specific execution processes of the steps S7 and S8 are not described herein again.

Step S6 specifically includes:

s61: and self-checking is carried out through the low-temperature group control subsystem, if the state of the low-temperature group control subsystem is abnormal, the operation data of the low-temperature equipment is collected through the standby control subsystem, and a low-temperature standby control signal is generated according to the operation data of the low-temperature equipment so as to control the operation of the low-temperature equipment. And transmitting the operation data of the low-temperature equipment to the low-temperature group control subsystem through the standby control subsystem.

S62: and if the state of the low-temperature group control subsystem is normal, judging the heartbeat state through the signal transmission of the low-temperature group control subsystem and the standby control subsystem. The heartbeat state is online at the opposite end or offline at the opposite end.

Specifically, a heartbeat request is sent to the standby control subsystem through the low-temperature group master control software. And if the heartbeat response of the standby control subsystem is not received for the continuously set times, the heartbeat state of the low-temperature group control software is off-line at the opposite end. And if the heartbeat response of the standby control subsystem is received, the heartbeat state of the low-temperature group control software is that the opposite terminal is on line.

S63: and when the heartbeat state is off-line at the opposite end, the role state of the low-temperature group control subsystem is activated.

S64: when the heartbeat state is on-line at the opposite end, determining the role state of the low-temperature group control subsystem according to the starting time of the low-temperature group control subsystem and the starting time of the standby control subsystem; the role state is active or standby.

Specifically, if the start time of the low-temperature group master control software is earlier than the start time of the standby control subsystem, the role state of the low-temperature group master control software is activated. And if the starting time of the low-temperature group main control software is later than that of the standby control subsystem, the role state of the low-temperature group main control software is standby. And if the starting time of the low-temperature group main control software is equal to that of the standby control subsystem, restarting the low-temperature group control software, wherein the role state of the low-temperature group control software is standby.

S65: and when the role state is activated, acquiring the operation data of the low-temperature equipment through a low-temperature group control subsystem, and generating a low-temperature main control signal according to the operation data of the low-temperature equipment so as to control the operation of the low-temperature equipment. And transmitting the operation data of the low-temperature equipment to the standby control subsystem through the low-temperature group control subsystem.

S66: and when the role state is standby, acquiring the operation data of the low-temperature equipment through the standby control subsystem, and generating a low-temperature standby control signal according to the operation data of the low-temperature equipment so as to control the operation of the low-temperature equipment. And transmitting the operation data of the low-temperature equipment to the low-temperature group control subsystem through the standby control subsystem.

In order to better understand the scheme of the present invention, the following specifically describes the process of the present invention for solving the single point failure problem, that is, the specific execution process of the master-slave hot standby mechanism:

software state: abnormal and normal.

Heartbeat state: the opposite terminal is offline and the opposite terminal is online.

Role state: standby and activation.

Decision waiting period of role state: only present at software startup; and after the software operation is finished, normally executing the control logic.

Real-time data: that is, during the execution of the three steps involved in the control logic, the data buffered in the memory and changing with time belongs to the instantaneous value.

And (4) history recording: the real-time data is stored in a database according to a certain format, and the stored records do not change along with the change of time and belong to historical values.

Step 1, network configuration

In the main network, one of the ports of the low temperature group control subsystem 1 has an address of 192.168.4.1, and the port number is 4001. One of the network ports of the medium temperature group control subsystem 2 has the address of 192.168.4.2 and the port number of 4001. One of the network ports of the cooling water cluster control subsystem 3 has the address of 192.168.4.3 and the port number of 4001. The address of one of the network ports of the standby control subsystem 4 is 192.168.4.4, the port number is 4002, the address of one of the network ports of the standby control subsystem 4 is 192.168.4.4, the port number is 4003, the address of one of the network ports of the standby control subsystem 4 is 192.168.4.4, and the port number is 4004. The network port with the port number of 4002 establishes a link with the low-temperature group control subsystem 1, the network port with the port number of 4003 establishes a link with the medium-temperature group control subsystem 2, and the network port with the port number of 4004 establishes a link with the cooling water group control subsystem 3. This is three links on one of the two channels.

In the standby network, one of the ports of the low temperature group control subsystem 1 has the address of 192.168.5.4 and the port number of 5001. One of the network ports of the medium temperature group control subsystem 2 has the address of 192.168.5.3 and the port number of 5001. One of the cooling water cluster control subsystem 3 network ports has an address of 192.168.5.2 and a port number of 5001. The address of one of the spare control subsystem 4 network ports is 192.168.5.1, and the port number is 5002; the address of one of the network ports of the standby control subsystem 4 is 192.168.5.1, and the port number is 5003; one of the standby control subsystem 4 ports has an address of 192.168.5.1 and a port number of 5004. Wherein, the network port with the port number of 5002 establishes a link with the low-temperature group control subsystem 1; and a link is established between the net port with the port number of 5003 and the medium-temperature group control subsystem 2, and a link is established between the net port with the port number of 5004 and the cooling water group control subsystem 3. This is the other three links of one of the two channels.

The above two channels are double channels. The actual IP address and port number can be configured as needed. The above is only one example of the present embodiment. The requirement is that the primary and backup networks must be two separate, non-connectable segments. Each channel of the double channels uses the port multiplexing of the link, so that the three main control subsystems are connected with the standby control subsystem 4, and the two sides of the link are in one-to-one correspondence, thereby solving the problems of correspondence and identification of the system.

Step 2, starting a control subsystem and control software

After the preparation of the execution environment (network, power-on, industrial personal computer and the like) is finished, the low-temperature group control subsystem 1, the medium-temperature group control subsystem 2 and the cooling water group control subsystem 3 are respectively started, and the corresponding three sets of software are started.

Starting the standby control subsystem 4, wherein the standby control subsystem 4 is started actually by starting three sets of software in an industrial personal computer: low-temperature group backup control software (low-temperature group backup control unit), medium-temperature group backup control software (medium-temperature group backup control unit), and cooling water group backup control software (cooling water group backup control unit).

Step 3, when the system is started, the corresponding software executes the software self-check

And when the abnormality is detected, setting the software state as the abnormality, and not executing subsequent operation. The standby control subsystem 4 is used for acquiring the operation data of the low-temperature equipment and generating a low-temperature standby control signal according to the operation data of the low-temperature equipment so as to control the operation of the low-temperature equipment.

And when the abnormality is not detected, setting the software state as normal, and normally executing software state judgment, heartbeat state judgment, role state judgment, real-time data synchronization, historical record synchronization and control logic.

The following description takes the execution processes of the low-temperature group control subsystem 1 and the standby control subsystem 4 as examples:

angle of standing at the cryo-group control subsystem 1:

after the low-temperature group control subsystem 1 is started, the state of the software of the low-temperature group control subsystem is always detected, and when the abnormality is detected, the software state is set to be abnormal, the role state is set to be standby, and the subsequent steps are not executed. And when the abnormality is not detected, judging the heartbeat state.

Determination of heartbeat status

As shown in fig. 4, the low temperature group control subsystem 1 receives a heartbeat request from the low temperature group control unit in the standby control subsystem 4, and replies a heartbeat response. The low-temperature group control subsystem 1 sends a heartbeat request to the low-temperature group standby control unit and waits for the low-temperature group standby control unit to reply a heartbeat response. And if the heartbeat response of the low-temperature group control unit is not received for 3 times continuously, setting the heartbeat state of the low-temperature group control subsystem 1 as an opposite end offline state. And as long as 1 heartbeat response of the low-temperature group control unit is received, setting the heartbeat state of the low-temperature group control subsystem 1 to be on-line at the opposite end. Specifically, the low-temperature group control subsystem 1 and the low-temperature group control unit in the standby control subsystem perform interaction of heartbeat requests and heartbeat responses through the corresponding data interaction units.

Determination of character status

When the software is started, the role state is set to be standby, and then the decision waiting period is continuously set to be the role state for 5 seconds, and the judgment of the heartbeat state is continuously executed: and when the heartbeat state is offline at the opposite end (offline of the low-temperature group backup control unit), setting the role state of the low-temperature group control subsystem 1 as activated. When the heartbeat state is that the opposite terminal is on-line (the low-temperature group standby control unit is on-line): if the low-temperature group backup control unit is in the decision waiting period, comparing the software starting time of the low-temperature group control subsystem 1 with that of the low-temperature group backup control unit: and if the software starting time of the low-temperature group control subsystem 1 is earlier, setting the role state of the low-temperature group control subsystem 1 to be activated. And if the software starting time of the low-temperature group control subsystem 1 is late, setting the role state of the low-temperature group control subsystem 1 as standby. And if the software starting time of the low-temperature group control subsystem 1 is equal to the software starting time of the low-temperature group backup control unit, restarting the software of the low-temperature group control subsystem 1. And if the low-temperature group control unit is not in the decision waiting period, setting the role state of the low-temperature group control subsystem 1 as standby.

Quitting the decision waiting period of the role state and entering the software operation

When the role state of the low-temperature group control subsystem 1 is activated:

when the heartbeat state of the low-temperature group control subsystem 1 is offline at the opposite end (the low-temperature group standby control unit is offline), the role state of the low-temperature group control subsystem 1 is kept activated.

When the heartbeat state of the low-temperature group control subsystem 1 is on-line at the opposite end (the low-temperature group standby control unit is on-line), the role state of the low-temperature group control subsystem 1 is kept to be activated.

The role state of the low temperature group control subsystem 1 can be set to standby manually.

In the embodiment, the active state is only converted into the standby state when the software self-test finds a fault, and the active state can only be manually switched at the rest time. The software itself is always self-checking.

When the role state of the low-temperature group control subsystem 1 is standby:

and when the heartbeat state of the low-temperature group control subsystem 1 is off-line at the opposite end (the low-temperature group standby control unit is off-line), setting the role state of the low-temperature group control subsystem 1 as activated.

When the heartbeat state of the low-temperature group control subsystem 1 is on-line at the opposite end (the low-temperature group standby control unit is on-line), the role state of the low-temperature group control subsystem 1 is kept to be standby.

Real-time data synchronization

And when the role state of the low-temperature group control subsystem 1 is activated, executing control logic, wherein the control logic comprises three steps of parameter acquisition, logic operation and parameter output. Parameter acquisition: and communicating with a controlled object of the entity, and collecting data from the equipment layer to form input parameters of the software. And (3) logical operation: based on the prepared input parameters, logical operations related to process control are performed, and operation results are obtained as output parameters. And (3) parameter output: and outputting the final parameters to the controlled object, namely feeding back the control signals to the entity equipment. And real-time data related to the control logic is packaged and sent to the low-temperature cluster standby control unit.

And when the role state of the low-temperature group control subsystem 1 is standby, receiving the real-time data sent by the low-temperature group control unit, and using the received real-time data to cover the real-time data of the software. And performing logic operation by using the covered real-time data, but not performing parameter acquisition and parameter output.

History synchronization

When the role state of the low-temperature group control subsystem 1 is activated, real-time data of software is used and formatted into a history record, and the history record is stored and a cache record to be synchronized is generated by utilizing database transactions.

And accessing a to-be-synchronized cache record of the low-temperature group backup control unit, reading a history record of the low-temperature group backup control unit corresponding to the cache, storing the history record into a database of the low-temperature group control subsystem 1, and clearing the to-be-synchronized cache record after the history record is successful.

When the role state of the low temperature group control subsystem 1 is standby, the storage of the history is not performed.

In addition, the angle of the control unit for the low-temperature group equipment is the same as the above steps, but the angle is different, and the description is omitted.

According to the invention, through an independent dual-network dual-system redundancy design method and an N +1 hot standby mechanism, when a redundancy structure is used, the hardware cost is reduced, an additional decision layer is avoided, and the problems of dual-master or dual-standby operation and 'consistent output' of dual-master dual-active structures are solved.

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. For the system disclosed by the embodiment, the description is relatively simple because the system corresponds to the method disclosed by the embodiment, and the relevant points can be referred to the method part for description.

The principles and embodiments of the present invention have been described herein using specific examples, which are provided only to help understand the method and the core concept of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.

Claims (9)

1. A control system of a central air conditioner is used for controlling low-temperature equipment, medium-temperature equipment and cooling water equipment of the central air conditioner, and is characterized by comprising the following components: the system comprises a main network, a standby network, a main exchanger, a standby exchanger, a low-temperature group control subsystem, a medium-temperature group control subsystem, a cooling water group control subsystem and a standby control subsystem;

the low-temperature group control subsystem, the medium-temperature group control subsystem, the cooling water group control subsystem and the standby control subsystem are all connected into the main network through the main switch;

the low-temperature group control subsystem, the medium-temperature group control subsystem, the cooling water group control subsystem and the standby control subsystem are all connected to the standby network through the standby switch;

when the main network and the main exchanger do not have faults, the low-temperature group control subsystem, the medium-temperature group control subsystem and the cooling water group control subsystem carry out signal transmission with the standby control subsystem through the main network and the main exchanger;

when the main network or the main exchanger fails, the low-temperature group control subsystem, the medium-temperature group control subsystem and the cooling water group control subsystem perform signal transmission with the standby control subsystem through the standby network and the standby exchanger;

the low-temperature group control subsystem is connected with the low-temperature equipment and is used for controlling the low-temperature equipment;

the medium-temperature group control subsystem is connected with the medium-temperature equipment and is used for controlling the medium-temperature equipment;

the cooling water group control subsystem is connected with the cooling water equipment and is used for controlling the cooling water equipment;

the standby control subsystem is used for controlling the low-temperature equipment or the medium-temperature equipment or the cooling water equipment when the low-temperature group control subsystem or the medium-temperature group control subsystem or the cooling water group control subsystem is abnormal.

2. The control system of central air conditioner according to claim 1, wherein said cryo-cluster control subsystem comprises:

the low-temperature data interaction unit is connected with the standby control subsystem and is used for carrying out signal transmission with the standby control subsystem through the main network and the main switch when the main network and the main switch are not in fault, and carrying out signal transmission with the standby control subsystem through the standby network and the standby switch when the main network or the main switch is in fault so as to carry out heartbeat state judgment and role state judgment; the heartbeat state is online at the opposite end or offline at the opposite end; the role state is activated or standby;

the low-temperature data acquisition unit is used for acquiring the operation data of the low-temperature equipment;

and the low-temperature main control unit is connected with the low-temperature data interaction unit, the low-temperature data acquisition unit and the low-temperature equipment and is used for generating a low-temperature main control signal according to the operation data of the low-temperature equipment when the heartbeat state is an opposite end offline state and the role state is activated so as to control the operation of the low-temperature equipment.

3. The control system of a central air conditioner according to claim 1, wherein the standby control subsystem includes:

the low-temperature group backup control unit is connected with the low-temperature equipment and used for transmitting signals with the low-temperature group control subsystem through the main network and the main switch when the main network and the main switch are not in fault, transmitting signals with the low-temperature group control subsystem through the standby network and the standby switch when the main network or the main switch is in fault so as to judge the heartbeat state, judge the role state, synchronize real-time data and synchronize historical records, collecting the operation data of the low-temperature equipment when the heartbeat state is offline at the opposite end and the role state is activated, and generating a low-temperature backup control signal according to the operation data of the low-temperature equipment so as to control the operation of the low-temperature equipment;

the medium-temperature group control unit is connected with the medium-temperature equipment and is used for transmitting signals with the medium-temperature group control subsystem through the main network and the main switch when the main network and the main switch are not in fault, transmitting signals with the medium-temperature group control subsystem through the standby network and the standby switch when the main network or the main switch is in fault so as to judge the heartbeat state, judge the role state, synchronize real-time data and synchronize historical records, collecting the operation data of the medium-temperature equipment when the heartbeat state is offline at the opposite end and the role state is activated, and generating a medium-temperature standby control signal according to the operation data of the medium-temperature equipment so as to control the operation of the medium-temperature equipment;

the cooling water crowd is equipped with the control unit, with the cooling water equipment is connected, is used for the main network reaches when the main switch does not break down, through the main network reaches the main switch with cooling water crowd control subsystem carries out signal transmission when main network or main switch break down, through the standby network with the standby switch with cooling water crowd control subsystem carries out signal transmission to carry out heartbeat state judgement, role state judgement, real-time data synchronization and historical record synchronization, and when the heartbeat state is the off-line of opposite end and the role state is the activation, gather the operational data of cooling water equipment, according to the operational data production cooling water of cooling water equipment is equipped with control signal, in order to control the operation of cooling water equipment.

4. The control system of central air conditioner as claimed in claim 1, wherein said cryo-group control subsystem has two ethernet ports: a first network port and a second network port;

the low-temperature group control subsystem is connected with the main switch through a first network port, and the low-temperature group control subsystem is connected with the standby switch through a second network port.

5. A control method of a central air conditioner, applied to the control system of the central air conditioner as claimed in any one of claims 1 to 4, wherein the control method of the central air conditioner comprises:

the low-temperature group control subsystem, the medium-temperature group control subsystem, the cooling water group control subsystem and the standby control subsystem are connected into a main network through a main switch;

the low-temperature group control subsystem, the medium-temperature group control subsystem, the cooling water group control subsystem and the standby control subsystem are connected into a standby network through a standby switch;

judging whether the main network and the main switch operate normally or not;

if the main network and the main exchanger operate normally, the low-temperature group control subsystem, the medium-temperature group control subsystem and the cooling water group control subsystem perform signal transmission with the standby control subsystem through the main network and the main exchanger;

if the main network or the main exchanger fails, the low-temperature group control subsystem, the medium-temperature group control subsystem and the cooling water group control subsystem perform signal transmission with the standby control subsystem through the standby network and the standby exchanger;

judging whether the low-temperature group control subsystem normally operates, if so, controlling low-temperature equipment through the low-temperature group control subsystem, and otherwise, controlling the low-temperature equipment through the standby control subsystem;

judging whether the medium-temperature group control subsystem normally operates, if so, controlling medium-temperature equipment through the medium-temperature group control subsystem, and otherwise, controlling the medium-temperature equipment through the standby control subsystem;

and judging whether the cooling water group control subsystem normally operates, if so, controlling cooling water equipment through the cooling water group control subsystem, and otherwise, controlling the cooling water equipment through the standby control subsystem.

6. The method as claimed in claim 5, wherein the determining whether the low temperature group control subsystem operates normally, if so, controlling the low temperature equipment through the low temperature group control subsystem, otherwise, controlling the low temperature equipment through the standby control subsystem, specifically includes:

the method comprises the steps that self-checking is carried out through a low-temperature group control subsystem, if the state of the low-temperature group control subsystem is abnormal, the standby control subsystem is used for collecting the operation data of low-temperature equipment and generating a low-temperature standby control signal according to the operation data of the low-temperature equipment so as to control the operation of the low-temperature equipment;

if the state of the low-temperature group control subsystem is normal, judging the heartbeat state through the signal transmission of the low-temperature group control subsystem and the standby control subsystem; the heartbeat state is that the opposite terminal is on-line or the opposite terminal is off-line;

when the heartbeat state is off-line at the opposite end, the role state of the low-temperature group control subsystem is activated;

when the heartbeat state is on-line at the opposite end, determining the role state of the low-temperature group control subsystem according to the starting time of the low-temperature group control subsystem and the starting time of the standby control subsystem; the role state is activated or standby;

when the role state is activated, acquiring the operation data of the low-temperature equipment through a low-temperature group control subsystem, and generating a low-temperature main control signal according to the operation data of the low-temperature equipment so as to control the operation of the low-temperature equipment;

and when the role state is standby, acquiring the operation data of the low-temperature equipment through the standby control subsystem, and generating a low-temperature standby control signal according to the operation data of the low-temperature equipment so as to control the operation of the low-temperature equipment.

7. The method as claimed in claim 6, wherein the determining the heartbeat status through the signal transmission between the cryo-cluster control subsystem and the standby control subsystem comprises:

sending a heartbeat request to the standby control subsystem through the low-temperature group control subsystem;

if the heartbeat response of the standby control subsystem is not received by the continuous set times, the heartbeat state of the low-temperature group control subsystem is off-line at the opposite end;

and if the heartbeat response of the standby control subsystem is received, the heartbeat state of the low-temperature group control subsystem is that the opposite terminal is on line.

8. The method according to claim 6, wherein the determining the role status of the low temperature group control subsystem according to the start time of the low temperature group control subsystem and the start time of the standby control subsystem comprises:

if the starting time of the low-temperature group control subsystem is earlier than that of the standby control subsystem, the role state of the low-temperature group control subsystem is activated;

if the starting time of the low-temperature group control subsystem is later than that of the standby control subsystem, the role state of the low-temperature group control subsystem is standby;

and if the starting time of the low-temperature group control subsystem is equal to that of the standby control subsystem, restarting the low-temperature group control subsystem, wherein the role state of the low-temperature group control subsystem is standby.

9. The method as claimed in claim 6, wherein the determining whether the cryo-cluster control subsystem is operating normally, if so, controlling the cryo-device through the cryo-cluster control subsystem, otherwise, controlling the cryo-device through the standby control subsystem further comprises:

when the standby control subsystem controls the operation of the low-temperature equipment, the standby control subsystem sends the operation data of the low-temperature equipment to the low-temperature group control subsystem;

when the low-temperature group control subsystem controls the operation of the low-temperature equipment, the operation data of the low-temperature equipment is sent to the standby control subsystem through the low-temperature group control subsystem.

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