A building control system and building control method based on cascade link

Abstract

The embodiment of the present application provides a building control system and a building control method based on cascade links, the system includes: a server and several DDC controllers, each DDC controller is provided with two network ports externally, the two network ports of each DDC controller are connected to different DDC controllers, and are used to realize chain cascade between DDC controllers, the DDC controller at the head end of the chain cascade is connected to the server; the DDC controller is used to receive the message sent by the server in the downstream direction of the chain cascade, forward the message that does not belong to the local processing of the DDC controller to other DDC controllers in the system in the chain cascade, receive the message that belongs to the local processing of the DDC controller and process it locally. Each DDC controller in the embodiment of the present application is connected to the server through chain cascade, and can realize long-distance communication in building control without switching equipment in large building projects, effectively reducing equipment cost, installation space, construction and maintenance cost.

Description

Technical Field

[0001] The present application relates to the field of industrial control technology, and in particular to a building control system and a building control method based on cascade links. Background Art

[0002] In current building systems, DDC controllers mainly exist in the following two forms:

[0003] The first type of DDC controller has no network port and only uses serial port, 485 and other protocols for communication. This method has certain limitations in data transmission speed and stability, especially in the face of large-scale data transmission and complex communication environment, its performance is difficult to meet the requirements.

[0004] The second type of DDC controller has a single network port. In this case, if the server wants to communicate with the DDC controller, an additional switch device must be added. With the rapid development of infrastructure at this stage, the indoor area that needs to be covered by building projects is increasing. When communication over 100 meters is required, traditional technology also requires the addition of relay equipment. As a result, in the current construction process, many problems such as complex wiring and increased costs will arise. For example, in some large commercial buildings or high-rise residential projects, due to the vast building area and long communication distance, traditional communication methods require a lot of wiring work, which not only increases the difficulty and time cost of construction, but also may cause difficulties in later maintenance due to complex lines. Summary of the invention

[0005] In view of this, the embodiments of the present application provide a building control system and a building control method based on cascade links. In the technical solution of the embodiments of the present application, each DDC controller is provided with two network ports to the outside, so that each DDC controller can be connected to the server through a chain cascade. Each DDC controller forwards the messages that are not processed locally to other DDC controllers in the downstream direction of the chain cascade, and processes the messages that are processed locally by the DDC controller. In large-scale building projects, long-distance communication of building control can be achieved without switching equipment, which greatly saves equipment costs and installation space, and significantly reduces the complexity of construction wiring, avoids line crossing and confusion, and effectively reduces construction and maintenance costs.

[0006] In the first aspect, an embodiment of the present application provides a building control system based on cascade links, including: a server and several DDC controllers, each DDC controller is provided with two network ports externally, and the two network ports of each DDC controller are connected to different DDC controllers for realizing a chain cascade between DDC controllers, wherein the DDC controller at the head end of the chain cascade is connected to the server; a DDC controller for receiving messages sent by the server in the downstream direction of the chain cascade, forwarding messages that are not processed locally by the DDC controller to other DDC controllers in the system in the chain cascade, receiving messages that are processed locally by the DDC controller and processing them locally; an IO input and output module connected to the DDC controller, for collecting field data from field equipment under the control of the DDC controller, or reporting collected field status data to the DDC controller, or executing actions to control field equipment.

[0007] As mentioned above, by setting two network ports for each DDC controller, each DDC controller can be connected to the server through chain cascading. Each DDC controller forwards the messages that are not processed by the local controller to other DDC controllers in the downstream direction of the chain cascade, and processes the messages that are processed by the DDC controller locally. In large-scale building projects, long-distance communication of building control can be achieved without switching equipment, which greatly saves equipment cost and installation space, and significantly reduces the complexity of construction wiring, avoids line crossing and confusion, and effectively reduces construction and maintenance costs.

[0008] In a possible implementation of the first aspect, the DDC controller is also used to receive messages carrying field data sent by other DDC controllers from the upstream direction of the chain cascade, and send them to the server through the upstream direction of the chain cascade, or, send the field data collected from the field device by the IO input and output module connected to the local machine to the server in the upstream direction of the chain cascade.

[0009] From the above, the DDC controller forwards the messages carrying field data sent by other DDC controllers from the upstream direction of the chain cascade, or sends the field data collected by the local machine from the field equipment to the server, thereby realizing data transmission in the upstream direction of the chain cascade, and further realizing medium and long distance communication of building control at low cost in large building projects without switching equipment.

[0010] In a possible implementation manner of the first aspect, the two network ports of each DDC controller are configured in a VLAN, and the VLAN of each DDC controller is different.

[0011] Therefore, the signaling disturbance in the building control system is reduced through the above VLAN configuration.

[0012] In a possible implementation manner of the first aspect, each DDC controller includes a DDC-M switching module and a DDC-P control module; the DDC-M switching module of each DDC controller is used to realize the interaction between the DDC controller and the server through the chain cascade, forward messages that are not processed by the DDC controller in the chain cascade, and transfer local messages to the local DDC-P control module; the DDC-P control module of each DDC controller is used to collect field data from the field device and / or send control commands to the field device according to the command of the message after receiving the message forwarded by the DDC-M switching module of the local device.

[0013] From the above, each DDC controller includes a DDC-M switching module and a DDC-P control module and is implemented on dedicated hardware, isolating the impact between message interaction and real-time control. The DDC-M switching module is used to forward downlink data in the chain cascade, and in large building projects, medium and long-distance communication of building control can be achieved at low cost without switching equipment.

[0014] In a possible implementation manner of the first aspect, the IP addresses of the two network ports of each DDC controller are the same.

[0015] From the above, the IP addresses of the two network ports of each DDC controller are the same, so that each controller has one IP address as a whole, which is the easiest to address the DDC controller.

[0016] In a possible implementation of the first aspect, the DDC-M switching module of each DDC controller is configured with the two network ports of the DDC controller and a third network port connected to the DDC-P control module of the DDC controller, and the IP address of the third network port is different from the IP addresses of the two network ports of the DDC controller; the DDC-P control module of each DDC controller is used to connect to the IO input and output module.

[0017] As described above, the IP address of the third network port of each DDC controller is different from the IP addresses of the other two network ports of the DDC controller, thereby further reducing signaling disturbances in the building control system.

[0018] In a possible implementation of the first aspect, the DDC-M switching module of each DDC controller is further used to receive messages carrying field data sent by other DDC controllers from the upstream direction of the chain cascade, and send them to the server through the upstream direction of the chain cascade, or, to send the field data collected from the field device by the IO input and output module connected to the local machine to the server in the upstream direction of the chain cascade.

[0019] From the above, the DDC-M switching module is used to realize the forwarding of uplink data in the chain cascade, and in large building projects, medium and long-distance communication of building control can be achieved at low cost without switching equipment.

[0020] In a possible implementation manner of the first aspect, the DDC-M of each DDC controller is further configured to update the MAC forwarding table entries in the chain cascade through MAC address learning and aging during message forwarding.

[0021] As described above, each DDC controller updates the MAC forwarding table entries in the chain cascade through MAC address learning and aging, so that when the DDC controller is increased or decreased or the IP address is modified, the MAC forwarding table entries can be automatically updated without manual configuration.

[0022] In a possible implementation manner of the first aspect, the DDC-M of each DDC controller is further used to statically configure a MAC forwarding table entry in the chain cascade.

[0023] As described above, the DDC-M switching module of each DDC controller statically configures a number of MAC forwarding table entries, thereby eliminating the need for learning and aging of these MAC forwarding table entries, thereby maintaining real-time communication.

[0024] In a possible implementation manner of the first aspect, each DDC controller interacts with the IOM module connected to it via an AUTBUS bus; the server and each DDC controller, and each DDC controller interacts with each other via ModbusTCP messages.

[0025] From the above, each DDC controller interacts with the IOM module connected to it through the AUTBUS bus and interacts through Modbus TCP messages in the chain cascade of the DDC controller, thereby integrating Modbus TCP with the AUTBUS bus and utilizing the high-speed, real-time and multi-node characteristics of the AUTBUS bus to achieve real-time control of the control devices that have increased multiples.

[0026] In a possible implementation of the first aspect, each DDC controller implements conversion between the logical address of the field device of the DDC controller in the Modbus TCP message and the device ID of the connected IO input / output module and the IO port of the IO input / output module through a local address mapping table.

[0027] As described above, each DDC controller realizes the conversion between the logical address and the device ID of the connected IO input and output module and the IO port of the IO input and output module through the local address mapping table, which can flexibly expand the field devices controlled by each DDC controller.

[0028] In a second aspect, an embodiment of the present application provides a building control method, which is controlled by the system described in any of the methods of the first aspect, including: the DDC controller of the system receives messages sent by the server of the system in the downstream direction of the chain cascade, forwards messages that are not processed locally by the DDC controller to other DDC controllers in the system in the chain cascade, receives messages that are processed locally by the DDC controller and processes them locally; an IO input and output module connected to the DDC controller collects field data from field equipment under the control of the DDC controller, or reports the collected field data to the DDC controller, or executes actions to control field equipment.

[0029] As shown above, each DDC controller is connected to the server through chain cascading, and obtains the downlink message sent by the server through chain cascading. In large-scale building projects, long-distance communication of building control can be achieved without switching equipment, which greatly saves equipment cost and installation space, and significantly reduces the complexity of construction wiring, avoids line crossing and confusion, and effectively reduces construction and maintenance costs.

[0030] In a possible implementation of the second aspect, it also includes: the DDC controller receives messages carrying field data sent by other DDC controllers from the upstream direction of the chain cascade, and sends them to the server through the upstream direction of the chain cascade, or, the field data collected from the field device by the IO input and output module connected to the local machine is sent to the server in the upstream direction of the chain cascade.

[0031] From the above, the DDC controller forwards the messages carrying field data sent by other DDC controllers from the upstream direction of the chain cascade, or sends the field data collected by the local machine from the field equipment to the server, thereby realizing data transmission in the upstream direction of the chain cascade, and further realizing medium and long distance communication of building control at low cost in large building projects without switching equipment.

[0032] In a possible implementation manner of the second aspect, two network ports of each DDC controller used to implement the chain cascade are configured in one VLAN, and the VLAN of each DDC controller is different.

[0033] Therefore, the signaling disturbance in the building control system is reduced through the above VLAN configuration.

[0034] In a possible implementation manner of the second aspect, each DDC controller includes a DDC-M switching module and a DDC-P control module; the DDC-M switching module of each DDC controller realizes interaction between the DDC controller and the server through the chain cascade, forwards messages that are not processed by the DDC controller in the chain cascade, and transfers local messages to the local DDC-P control module; after receiving the message forwarded by the local DDC-M switching module, the DDC-P control module of each DDC controller collects field data from the field device and / or sends a control command to the field device according to the command of the message.

[0035] From the above, each DDC controller includes a DDC-M switching module and a DDC-P control module, which are located on different chips respectively, so that data exchange and control are isolated in hardware; and the DDC-M switching module realizes the forwarding of downlink data in the chain cascade, and in large building projects, medium and long-distance communication of building control can be achieved at low cost without switching equipment.

[0036] In a possible implementation manner of the second aspect, the IP addresses of the two network ports of each DDC controller are the same.

[0037] From the above, the IP addresses of the two network ports of each DDC controller are the same, so that each controller has one IP address as a whole, which is the easiest to address the DDC controller.

[0038] In a possible implementation of the second aspect, the DDC-M switching module of each DDC controller is configured with the two network ports of the DDC controller and a third network port connected to the DDC-P control module of the DDC controller, and the IP address of the third network port is different from the IP addresses of the two network ports of the DDC controller that implement the chain cascade; the DDC-P control module of each DDC controller is connected to the IO input and output module.

[0039] As described above, the IP address of the third network port of each DDC controller is different from the IP addresses of the other two network ports of the DDC controller, thereby further reducing signaling disturbances in the building control system.

[0040] In a possible implementation of the second aspect, the DDC-M switching module of each DDC controller receives messages carrying field data sent by other DDC controllers from the upstream direction of the chain cascade, and sends them to the server through the upstream direction of the chain cascade, or, the field data collected from the field device by the IO input and output module connected to the local device is sent to the server in the upstream direction of the chain cascade.

[0041] From the above, the DDC-M switching module is used to realize the forwarding of uplink data in the chain cascade, and in large building projects, medium and long-distance communication of building control can be achieved at low cost without switching equipment.

[0042] In a possible implementation manner of the second aspect, the method further includes: during a message forwarding process, the DDC-M of each DDC controller updates a MAC forwarding table entry in the chain cascade through MAC address learning and aging.

[0043] As described above, each DDC controller updates the MAC forwarding table entries in the chain cascade through MAC address learning and aging, so that when the DDC controller is increased or decreased or the IP address is modified, the MAC forwarding table entries can be automatically updated without manual configuration.

[0044] In a possible implementation manner of the second aspect, the further comprising: a DDC-M of each DDC controller statically configures a MAC forwarding table entry in the chain cascade.

[0045] As described above, the DDC-M switching module of each DDC controller statically configures a number of MAC forwarding table entries, thereby eliminating the need for learning and aging of these MAC forwarding table entries, thereby maintaining real-time communication.

[0046] In a possible implementation manner of the second aspect, each DDC controller interacts with the IOM module connected to it via an AUTBUS bus; the server and each DDC controller, and each DDC controller interacts with each other via ModbusTCP messages.

[0047] From the above, each DDC controller interacts with the IOM module connected to it through the AUTBUS bus and interacts through Modbus TCP messages in the chain cascade of the DDC controller, thereby integrating Modbus TCP with the AUTBUS bus and utilizing the high-speed, real-time and multi-node characteristics of the AUTBUS bus to achieve real-time control of the control devices that have increased multiples.

[0048] In a possible implementation of the second aspect, it also includes: each DDC controller implements the conversion between the logical address of the field device of the DDC controller in the Modbus TCP message and the device ID of the connected IO input and output module and the IO port of the IO input and output module through a local address mapping table.

[0049] As described above, each DDC controller realizes the conversion between the logical address and the device ID of the connected IO input and output module and the IO port of the IO input and output module through the local address mapping table, which can flexibly expand the field devices controlled by each DDC controller. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 This is a structural diagram of a first embodiment of a building control system based on cascade links of the present application;

[0051] Figure 2 This is a structural diagram of a second embodiment of a building control system based on cascade links of the present application;

[0052] Figure 3 This is a schematic diagram showing the data frame format of the VLAN of the present application;

[0053] Figure 4 A schematic diagram of a network topology of a cascaded DDC controller in a second embodiment of a building control system based on a cascade link of the present application;

[0054] Figure 5 A schematic diagram of the connection between each DDC controller and the IOM module in Embodiment 2 of a building control system based on cascade link of the present application;

[0055] Figure 6 A schematic diagram of SCADA for building air conditioning intelligent control scenarios in Example 2 of a building control system based on cascade links of the present application;

[0056] Figure 7 A schematic diagram of a flow chart of a first embodiment of a building control method of the present application;

[0057] Figure 8 This is a flow chart of a second embodiment of a building control method of the present application;

[0058] Fig. 9 A schematic diagram of a flow chart of a server sending a message to a first DDC controller in Embodiment 2 of a building control method of the present application;

[0059] Fig.10 This is a flow chart of a second DDC controller sending a message to a server in Embodiment 2 of a building control method of the present application. DETAILED DESCRIPTION

[0060] In the following description, reference is made to “some embodiments”, which describe a subset of all possible embodiments, but it will be understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0061] In the following description, the terms "first\second\third, etc." or module A, module B, module C, etc. are only used to distinguish similar objects, or to distinguish different embodiments, and do not represent a specific ordering of the objects. It can be understood that the specific order or sequence can be interchanged where permitted, so that the embodiments of the present application described here can be implemented in an order other than that illustrated or described here.

[0062] In the following description, the numbers representing the steps, such as S110, S120, etc., do not necessarily mean that the steps must be executed in this manner. If permitted, the order of the previous and next steps can be interchanged, or they can be executed simultaneously.

[0063] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein are only for the purpose of describing the embodiments of this application and are not intended to limit this application.

[0064] The following is an introduction to the terms involved in this application.

[0065] The DDC controller (Direct Digital Controller) measures the characteristic parameters and process parameters of field equipment and controls the field equipment. Field equipment includes sensors and actuators.

[0066] IO input / output module (IOM) is an electronic device used to process input and output. It is used in industrial automation systems to receive input signals from sensors or other devices through IO ports and convert the output signals of the control system into a form that can drive actuators or other devices.

[0067] AUTBUS bus is a broadband field bus that uses two-wire non-bridge media and OFDM technology at the physical layer. When the transmission distance of AUTBUS bus is 500 meters, the transmission rate is 100Mps; when the transmission distance is 2500 meters, the transmission rate is 6.25Mbps. It supports up to 254 nodes. The twisted pair has no polarity and the wiring is simple. It supports mixed carrying of real-time and non-real-time business data to ensure the certainty and real-time nature of various data transmissions.

[0068] In addition, the AUTBUS bus has excellent communication security performance. Through strict encryption and authentication mechanisms, strict security protection is carried out in every link of data transmission. This not only ensures the security and integrity of data during transmission, but also effectively prevents the risk of data being maliciously tampered with or stolen. In today's digital age, data security in building systems is extremely important, and the security mechanism of the AUTBUS bus provides reliable protection for the safe and stable operation of buildings.

[0069] In addition, the AUTBUS bus has significant advantages in supporting the number of IOM slaves. It can meet the connection requirements of a large number of input and output modules in large building systems, greatly improving the scalability and flexibility of the system. Whether it is a large number of sensors and actuators in commercial buildings or a complex equipment control system in an industrial plant, the AUTBUS bus can easily cope with it and achieve efficient data communication and equipment management.

[0070] The nodes of the AUTBUS bus include control nodes (CN) and terminal nodes (TN). CN: Control nodes in the AUTBUS network, which complete network control and communicate with all TN nodes. TN: Terminal nodes in the AUTBUS network, TN nodes can communicate with CN or TN nodes.

[0071] The Modbus TCP protocol uses the master-slave mode. The Modbus TCP master collects data from multiple Modbus TCP slave devices in real time, and then issues instructions to the Modbus TCP slave devices according to the preset control algorithms and strategies. The Modbus TCP slave is a device used for data acquisition and control signal output. It is usually a slave device of the Modbus TCP master and works with the Modbus TCP master to monitor and control field devices.

[0072] The ModbusTCP protocol is widely used in the field of industrial control with its simple and efficient frame format. Its typical structure includes address field, function code, data field and check code. For example, the address field is used to identify different slaves, the function code indicates the specific operation type, the data field carries the actual data content, and the check code ensures the accuracy of data transmission.

[0073] The embodiment of the present application provides a building control system and a building control method based on cascade links, the system comprising: a server and a plurality of DDC controllers, each DDC controller being provided with two network ports for external use, the two network ports of each DDC controller being connected to different DDC controllers for realizing a chain cascade between DDC controllers, the DDC controller at the head end of the chain cascade being connected to the server; a DDC controller being used to receive messages sent by the server in the downstream direction of the chain cascade, forward messages that are not processed locally by the DDC controller to other DDC controllers in the system in the chain cascade, receive messages that are processed locally by the DDC controller and process them locally; an IO input / output module connected to the DDC controller, being used to collect field data from field equipment under the control of the DDC controller, or report the collected field data to the DDC controller, or execute actions to control field equipment.

[0074] In the technical solution of the embodiment of the present application, each DDC controller is provided with two network ports to the outside, so that each DDC controller can be connected to the server through a chain cascade. Each DDC controller forwards the messages that are not processed locally to other DDC controllers in the downstream direction of the chain cascade, and processes the messages that are processed locally by the DDC controller. In large-scale building projects, long-distance communication of building control can be achieved without switching equipment, which greatly saves equipment cost and installation space, and significantly reduces the complexity of construction wiring, avoids line crossing and confusion, and effectively reduces construction and maintenance costs.

[0075] The following describes various embodiments of the present application in conjunction with the accompanying drawings. Figure 1 A first embodiment of a building control system based on cascade links of the present application is introduced.

[0076] Figure 1 The structure of a first embodiment of a building control system based on cascade links is shown, including: a server and a plurality of DDC controllers, wherein the DDC controllers are identified from 1 to N.

[0077] The server is used to run the application program of the building control system, execute the control logic of the building control system, and issue control instructions to each DDC controller.

[0078] Each DDC controller is used to control the field equipment of the relevant floors or related functions of the building according to the control commands issued by the server. Each DDC controller controls several field devices through IO input and output modules. Figure 1 Controlling a field device via a control port is shown only as an example.

[0079] Each DDC controller is provided with a first network port and a second network port, which are used to connect each DDC controller to a server in a chain cascade manner, thereby simplifying the wiring of each DDC controller of the building control system and reducing the implementation cost.

[0080] in, Figure 1 The chain cascade method is: DDC controller 1 is connected to the server through the first network port, connected to the first network port of DDC controller 2 through the second network port, and DDC controller 2 is connected to the first network port of DDC controller 3 through the second network port; and so on, each DDC controller is connected to the server through a chain cascade method.

[0081] Among them, in the downstream direction of the chain cascade (the direction from the server to the DDC controller), each DDC controller receives the message sent by the server of the system from the downstream direction of the chain cascade, forwards the message that does not belong to the local processing of the DDC controller to other DDC controllers in the system in the chain cascade, receives the message that belongs to the local processing of the DDC controller and processes it locally, so that each DDC controller receives the message from the server through the chain cascade, and realizes medium and long distance communication of building control in large building projects without switching equipment, which greatly saves implementation and maintenance costs.

[0082] Among them, in the uplink direction of the chain cascade (the direction from the DDC controller to the server), each DDC controller receives the message carrying the field data sent by other DDC controllers from the uplink direction of the chain cascade, and sends it to the server through the uplink direction of the chain cascade, or sends the field data collected from the field device by the IO input and output module connected to the local machine to the server in the uplink direction of the chain cascade. From the above, the DDC controller forwards the message carrying the field data sent by other DDC controllers from the uplink direction of the chain cascade or sends the field data collected by the local machine from the field device to the server, so as to realize the data transmission in the uplink direction of the chain cascade, and further realizes the medium and long distance communication of building control at low cost without switching equipment in large building projects.

[0083] Wherein, no matter in the downstream or upstream direction of the chain cascade, the data exchanged between each DDC controller and the server is transmitted based on TCP stream, each TCP stream includes several sequence TCP packets, and the TCP ACK pair is used to confirm whether each sequence TCP packet is successfully received based on the TCP window.

[0084] The IO input and output module connected to the DDC controller collects field data from the field, reports the collected field data to the DDC controller, or enables the field equipment to perform control actions under the control of the DDC controller.

[0085] Among them, when the downlink message sent by the server includes a collection instruction for collecting field data and the DDC controller has no field data cache, the IO input and output module collects field data from the field equipment under the control of the DDC controller; when the downlink message sent by the server includes a collection instruction for collecting field data and the DDC controller has a field data cache (the cached data is acquired through periodic collection by the IO input and output module), the IO input and output module reports the cached field data to the DDC controller under the control of the DDC controller; when the downlink message sent by the server includes real-time control of field equipment to perform control actions, the IO input and output module enables the field equipment to perform control actions under the control of the DDC controller.

[0086] In some embodiments, each DDC controller acts as an agent of the IO input / output module to which it is connected, sets a cache address for each IO port of the IO input / output module to which it is connected, and periodically collects field data from the IO ports used to collect field data, and stores it in the caches corresponding to these IO ports.

[0087] In some embodiments, each DDC controller is connected to several IO input and output modules through a control port, each IO input and output module is connected to several field devices, each IO input and output module is in cascade form, and the control port can be a network port or other interface form. In other embodiments, each DDC controller is connected to several IO input and output modules in a star shape through several control ports, each IO input and output module is connected to several field devices, each IO input and output module is in parallel form, and the several control ports can be network ports or other interface forms.

[0088] In some embodiments, each DDC controller interacts with the IO input / output module connected to it via the AUTBUS bus to improve the bandwidth and real-time performance of the communication between each DDC controller and the IO input / output module. In other embodiments, each DDC controller is connected to the IO input / output module connected to it via a serial port or 485 port protocol.

[0089] In some embodiments, the first network port and the second network port of each DDC controller are configured in a VLAN, and the VLAN of each DDC controller is different, so that the signaling storm of the building control system is reduced through the above VLAN configuration.

[0090] In some embodiments, the IP address of the first network port and the second network port of each DDC controller is the same, which address can also be called the VLAN address or the address of the DDC controller. Each DDC controller is an address to the server and other controllers for easy addressing. In other embodiments, the IP address of the first network port and the second network port of each DDC controller is different.

[0091] In some embodiments, the server and each DDC controller, and each DDC controller interact with each other through Modbus TCP messages, and use the logical address in the Modbus TCP message to address each field device in the building control system. The logical address can use the local address mapping table of the DDC controller to convert the device ID of the IO input and output module connected to the field device and the IO port connected in the IO input and output module. The device ID of each IO input and output module is also used for the node identification on the AUTBUS bus where the IO input and output module is located. The local address mapping table of each DDC controller includes the mapping relationship between the device ID of the IO input and output module connected to the DDC controller and the IO port connected in the IO input and output module and the logical address in the Modbus TCP message.

[0092] In some embodiments, the server is a Modbus TCP master station, and each DDC controller is a Modbus TCP slave station. The server generates a local address mapping table for each DDC controller and sends it to each DDC controller.

[0093] In some embodiments, each DDC controller includes a DDC-M switching module and a DDC-P control module, and the DDC-M switching module and the DDC-P control module respectively run on different chips; the DDC-M switching module of each DDC controller is used to realize the interaction between the DDC controller and the server through chain cascading, and forward the messages that are not processed by the DDC controller in the chain cascading; the DDC-P control module of each DDC controller is used to obtain commands from the server through the DDC-M switching module of the DDC controller to collect field data from the field device and / or send control commands to the field device. By dividing the DDC controller into a DDC-M switching module for data exchange and a DDC-P control module for controlling the field device, the two parts are respectively run on independent chips, thereby increasing the isolation between them.

[0094] In some embodiments, the DDC-M switching module of each DDC controller is also used to receive messages carrying field data sent by other DDC controllers from the upstream direction of the chain cascade, and send them to the server through the upstream direction of the chain cascade, or send the field data collected from the field equipment by the IO input and output module connected to the local machine to the server in the upstream direction of the chain cascade, so that each DDC controller can send messages carrying field data to the server in the upstream direction through the chain cascade, and in large building projects, medium and long distance communication of building control can be achieved at low cost without switching equipment.

[0095] In some embodiments, the DDC-M switching module of each DDC controller sets the first network port and the second network port of the DDC controller and the third network port connected to the DDC-P control module of the DDC controller, and the IP address of the third network port is different from the IP address of the first network port and the IP address of the second network port of the DDC controller, so that the message in the chain cascade will not be forwarded on the third network port; the DDC-P control module of each DDC controller is used to connect to the field device. The DDC-M switching module of each DDC controller realizes the chain cascade with the server through the first network port and the second network port, and the DDC-M switching module of each DDC controller uses the third network port to connect to the field device through the DDC-P control module.

[0096] In some embodiments, the DDC-M switching module of each DDC controller is also used to update the MAC forwarding table entries in the chain cascade through MAC address learning and aging during the forwarding process, thereby dynamically adaptively tracking the changes in the IP addresses or MAC addresses of each DDC controller that may occur during maintenance based on the MAC forwarding table entries of each DDC controller.

[0097] In some embodiments, the DDC-M switching module of each DDC controller is also used to statically configure the MAC forwarding table items in the chained cascade, and these statically configured MAC forwarding table items remain unchanged during MAC address learning and aging to achieve fast forwarding of messages. Of course, the IP and MAC addresses related to the specific DDC controllers involved in these statically configured MAC forwarding table items in the building control system also remain unchanged.

[0098] In summary, in a first embodiment of a building control system based on cascade connection, each DDC controller is provided with two network ports to the outside, so that each DDC controller can be connected to a server through a chain cascade, and data interaction between the DDC controller and the server is realized through the chain cascade. In large-scale building projects, medium and long-distance communication of building control can be realized without switching equipment, which greatly saves equipment cost and installation space, and significantly reduces the complexity of construction wiring, avoids line crossing and confusion, and effectively reduces construction and maintenance costs.

[0099] Combine the following Figures 2 to 6 A second embodiment of a building control system based on cascade links is introduced.

[0100] A second embodiment of a building control system based on cascade links inherits all the structures of the first embodiment of a building control system based on cascade links and has all the advantages of the first embodiment of a building control system based on cascade links.

[0101] Each DDC controller is also connected to all IO input and output modules of the DDC controller through AUTBUS, so that the wiring between each DDC controller and the IO input and output module is simple and broadband-based real-time communication is realized. Combined with the broadband connection between the server and each DDC controller through the network port, the wiring of the entire control system is simple and supports wide connection, which improves the real-time control of field equipment.

[0102] The server interacts with each DDC controller and each DDC controller interacts with each other through Modbus TCP messages. The logical address in the Modbus TCP message is used to address each field device in the building control system. The logical address can use the address mapping table of each DDC controller to convert the device ID of the IO input and output module connected to the field device and the IO port connected in the IO input and output module. The address mapping table of each DDC controller flexibly defines the IO port connected in the IO input and output module, which is convenient for expanding field devices. The server is the master station of Modbus TCP, and each DDC controller is a slave station of ModbusTCP, and is also the master station of the AUTBUS bus.

[0103] Figure 2 The structure of a second embodiment of a building control system based on cascade links is shown. Each DDC controller is divided into a DDC-M switching module and a DDC-P control module, which respectively run on different chips of the DDC controller and are isolated in hardware.

[0104] The DDC-M switch module of each DDC controller sets the first network port of the DDC controller ( Figure 2 Eth interface 1) and the second network port ( Figure 2 The third network port ( Figure 2 The first network port and the second network port of the DDC-M switching module of each DDC controller realize the broadband chain cascade based on the network port between each DDC controller and the server, and the DDC-P control module of each DDC controller is provided with a fourth network port ( Figure 2 The interface in the figure is Eth interface 4).

[0105] The DDC-M switching module of each DDC controller is cascaded with the DDM of other DDC controllers and the server through Modbus TCP. The Modbus TCP message includes a logical address for addressing the IO port connected to the IO input and output module corresponding to the field device.

[0106] In the direction from the server to the DDC controller, the DDC-M switching module of each DDC controller determines whether it is a message processed by the DDC controller through the target IP address of the ModbusTCP message. If it is, the message is forwarded to the DDC-P control module of the DDC controller to control or configure the corresponding field device according to the logical address therein. If not, the message is forwarded to the next DDC controller in this direction.

[0107] In the direction from the DDC controller to the server, the DDC-M switching module of each DDC controller determines whether it is a message processed by the DDC controller through the target IP address of the ModbusTCP message. If it is, the message is forwarded to the DDC-P control module of the DDC controller to control the corresponding field device according to the logical address therein. If not, the message is forwarded to the next DDC controller or server in this direction.

[0108] The first network port and the second network port of the DDC-M switch module of each DDC controller are configured in a VLAN, and the VLAN of each DDC controller is different, thereby reducing the signaling storm of the building controller. The first network port and the second network port of the DDC-M switch module of each DDC controller have the same IP address, which can also be called the IP address of the DDC controller. Each DDC controller has an address for the server and other DDC controllers, which makes addressing more convenient. The third network port of the DDC-M switch module of each DDC controller is not in the VLAN of the DDC controller and is different from the IP address of the DDC controller.

[0109] Figure 3 The data frame format of VLAN is shown, and the fields of the VLAN data frame are explained as follows.

[0110]

[0111] After each DDC controller completes the VLAN configuration, a data transmission link is established between the DDC controllers through a chain cascade connection mode.

[0112] When the DDC-M switch module of the server and each DDC controller updates the MAC forwarding table entries through the MAC address learning and aging method, in the initial state, the VLAN of each DDC controller does not know the MAC address of the connected DDC controller and server, so the MAC forwarding table is empty. Before receiving the data frame sent by the server, there is no entry in the MAC forwarding table.

[0113] In the MAC address learning stage, when the server sends data to the physically connected DDC controller, it will first send an ARP request to obtain the MAC address of the DDC controller DDC-M switch module. The destination MAC address in this ARP request frame is the broadcast address, and the source MAC address is its own MAC address. After the first network port of the DDC controller DDC-M switch module receives the frame, it will add the mapping relationship between the source MAC address and the receiving port to the MAC forwarding table of the DDC controller DDC-M switch module, that is, obtain the MAC forwarding table entry through MAC address learning.

[0114] By default, the aging time of the MAC address table entry is 300 seconds. If a data frame sent by the server is received again within the aging time, the aging time of the server's MAC address and port number mapping stored in the VLAN of the DDC controller DDC-M switching module will be refreshed. After that, if the DDC controller DDC-M switching module receives a data frame with a target MAC address of the server's MAC, it will be forwarded through the first network port.

[0115] When the first network port of the DDC-M switch module of the DDC controller receives this data frame, it will check the ARP data frame. It will process the frame and send an ARP response. The destination MAC address of this reply data frame is the MAC address of the server, and the source MAC address is the MAC address of the first network port of the DDC-M switch module of the DDC controller. When the VLAN receives the reply data frame, it will add the mapping relationship between the source MAC address of the frame and the interface to the MAC forwarding table. If this mapping relationship already exists in the MAC forwarding table, it will be refreshed. After that, the VLAN queries the MAC forwarding table, finds the corresponding forwarding port according to the destination MAC address of the message, and sends the message.

[0116] When the destination MAC address of a data frame received by one of the first network port or the second network port of the DDC-M switching module of the DDC controller is not in the MAC forwarding table of the DDC-M switching module of the DDC controller, or the destination MAC address is a broadcast address, the DDC-M switching module of the DDC controller will flood the frame through the other network port of the first network port or the second network port.

[0117] The DDC-M switching module of each DDC controller also statically configures the MAC forwarding table entries in the chained cascade. These statically configured MAC forwarding table entries remain unchanged during MAC address learning and aging to achieve fast message forwarding. Of course, the IP and MAC addresses related to the specific DDC controllers involved in these statically configured MAC forwarding table entries in the building control system also remain unchanged.

[0118] In the DDC controller chain cascade architecture, each DDC controller is equipped with two network ports. This design not only simplifies the wiring complexity, but also improves the scalability and flexibility of the system. Figure 4 The network topology of the DDC controller cascade in the second embodiment of the building control system based on cascade link is shown. The connection wiring between the DDC controllers is flexible and convenient for expansion after the addition of new DDC controllers.

[0119] Figure 5 The figure shows a connection diagram between each DDC controller and IO input / output module in a second embodiment of a building control system based on cascade connection.

[0120] Each DDC controller's DDC-P control module is equipped with an ATB interface to connect to each IO input and output module through the AUTBUS bus, that is, the IO input and output module is also connected through the ATB interface ( Figure 5 Each IO input and output module is connected to the AUTBUS bus through several IO ports ( Figure 5 Each DDC controller is connected to each IO input and output module through the AUTBUS bus, so as to realize broadband and real-time communication between each DDC controller and the corresponding IO input and output module. In combination with each DDC controller being cascaded to the server through the network port, the communication from the server to the IO input and output module is broadband communication, which improves the real-time control of the field equipment.

[0121] The DDC-M switching module of each DDC controller determines whether the received Modbus TCP message is a message received by itself according to the target IP address of the received Modbus TCP message. If so, the logical address in the message is mapped to the device ID of the corresponding field device connected to the IO input and output module and the port ID of the IO port connected in the IO input and output module through the local address mapping table, and the Modbus TCP message is converted into an AUTBUS message, and the AUTBUS message is sent to the IO input and output module with the device ID as the target node ID of AUTBUS. The AUTBUS message includes control instructions and the IO port connected to the field device, so as to control the controlled device through the IO input and output module, including collecting data from the field device and making the field device perform actions; if not, the Modbus TCP message is forwarded to other DDC controllers or servers.

[0122] The local address mapping table of the DDC-M switching module of each DDC controller includes the mapping relationship between the logical address of the field device controlled by the DDC controller in the Modbus TCP message and the device ID of the IO input / output module connected to the field device and the port ID connected to the IO port in the IO input / output module. The logical address of each field device in the Modbus TCP message is different from the logical address of other field devices, and the device ID of each IO input / output module is different from the device ID of other IO input / output modules. According to the address mapping table of each DDC controller, the IO input / output module and IO port connected to each field device can be uniquely addressed.

[0123] Figure 6 The SCADA diagram of the second embodiment of a building control system based on cascade link for building air conditioning intelligent control scenario is shown. The indoor fan outlet, water valve, radiator, and cooling pump in the figure are all field devices that are controlled by the DDC controller of the building control system. Sensors for measuring CO2 concentration, indoor humidity, and indoor temperature are also field devices. Data is collected from these sensors through the DDC controller of the building control system. The SCADA software runs in the server.

[0124] In summary, a second embodiment of a building control system based on cascade links is based on the first embodiment of a building control system based on cascade links. Each DDC controller is connected to all IO input and output modules of the DDC controller via AUTBUS, so that the wiring between each DDC controller and the IO input and output module is simple, and broadband real-time communication is realized. Combined with the broadband connection between the server and each DDC controller through the network port, the wiring of the entire control system is simple, and both support wide connection, which improves the real-time control of field equipment. And through independent hardware isolation of the switching function and control function of the DDC controller, the real-time control and communication are further improved.

[0125] The following describes various method embodiments of the present application in conjunction with the accompanying drawings. Figure 7 A first embodiment of a building control method is introduced.

[0126] A building control method embodiment 1 uses a control system described in embodiment 1 of a building control system based on cascade links for control, and has all the advantages of embodiment 1 of a building control system based on cascade links.

[0127] Figure 7 The flowchart of a first embodiment of a building control method is shown, including steps S710 to S740.

[0128] S710: The server sends a downlink message for collecting field data to the first DDC controller through the chain cascade network.

[0129] The server executes the control logic of the building control system to generate a data collection instruction, which can be to collect field data from a corresponding field device or to obtain stored field data from a corresponding cache in the first DDC controller of the field device.

[0130] S720: The first DDC controller receives a downlink message from the chain cascade in the downlink direction, and obtains the collected field data.

[0131] When receiving downlink messages, the first DDC controller forwards the downlink messages that are not processed by the DDC controller itself to other DDC controllers in the system in a chain cascade, and receives messages that are processed by the controller itself.

[0132] Wherein, when the first DDC controller periodically obtains the field data of the field device through the IO input and output port and stores it in the corresponding cache, the first DDC controller obtains the field data from the corresponding cache according to the acquisition instruction. When there is no field data to be collected in the cache of the first DDC controller, the first DDC controller collects the field data of the field device through the IO input and output port.

[0133] S730: The first DDC controller feeds back an uplink message including field data to the server in the uplink direction of the chain cascade.

[0134] The first DDC controller receives messages carrying field data sent by other DDC controllers in the uplink direction of the chain cascade, and sends them to the server through the uplink direction of the chain cascade, and sends the field data collected by the local controller to the server through the corresponding uplink message.

[0135] S740: When the server triggers a control instruction based on the building control logic according to the collected data, a downlink message including the control instruction is sent to the second DDC controller.

[0136] The second DDC controller and the first DDC controller may be the same DDC controller or different DDC controllers.

[0137] S750: The second DDC controller enables the corresponding field device to perform a corresponding action according to the control instruction.

[0138] When receiving the downlink message including the control instruction, the second DDC controller forwards the downlink message that is not processed by the second DDC controller locally to other DDC controllers in the system in a chain cascade, and receives the message that is processed locally.

[0139] Wherein, the second DDC controller enables the corresponding field device to execute the corresponding action through the corresponding IO input and output port.

[0140] Combine the following Figure 8 A second embodiment of a building control method is introduced.

[0141] A building control method embodiment 2 uses a control system described in embodiment 2 of a building control system based on cascade links for control, and has all the advantages of embodiment 2 of a building control system based on cascade links.

[0142] Figure 8 The flowchart of the second embodiment of a building control method is shown, including steps S810 to S860.

[0143] S810: The server sends a downlink Modbus TCP message for collecting data to the first DDC controller.

[0144] The downlink Modbus TCP message includes a logical address of a field device used to collect data.

[0145] S820: The first DDC controller receives a downlink Modbus TCP message for collecting data, and receives collected data from the first field device according to a corresponding IO port in the IO input / output module corresponding to a logical address in the message.

[0146] Fig. 9 The detailed process of the server sending a message to the first DDC controller in this step is shown, which includes:

[0147] 1) The server sends the downlink ModbusTCP message to DDC controller 1 (not necessarily the first DDC controller) through the network port;

[0148] 2) DDC controller 1 determines whether DDC controller 1 is the first DDC controller according to the target IP address of the message, and if so, executes steps 3) and 4); if not, executes step 5);

[0149] 3) The DDC controller 1 parses the message, converts the logical address therein into the device ID of the IO input / output module connected to the first field device and the IO port number connected in the IO input / output module according to the local address mapping table, and sends a downlink AUTBUS message of collected data to the IO input / output module with the device ID as the target node ID;

[0150] 4) The IO input / output module receives the downlink AUTBUS message, sends a data collection command to the IO port connected to the first field device, and collects real-time data and device status through the first field device;

[0151] 5) DDC controller 1 forwards the Modbus TCP downlink message to DDC controller 2, and DDC controller 2 repeats the process of DDC controller 1 until the message reaches the first DDC controller.

[0152] S830: The first DDC controller feeds back the collected data to the server via an uplink Modbus TCP message.

[0153] Fig.10 The detailed process of the first DDC controller sending a message to the server in this step is shown, which includes:

[0154] 1) The IO input / output module connected to the first field device obtains the collection result and sends it to the first DDC controller via an uplink AUTBUS message. The first DDC controller is the DDC controller determined from DDC controllers 1 to N in step S820, and the message includes the collection result and the IO port number of the IO input / output module connected to the first field device.

[0155] 2) The first DDC controller parses the uplink AUTBUS message, generates an uplink Modbus TCP message, and sends it to the next DDC controller in the server direction. The message includes the logical address and collection results of the first field device, and the target IP address is the server;

[0156] 3) When the next DDC controller receives the uplink Modbus TCP message, it continues to forward it to the next DDC controller in the direction of the server according to the target IP address which is not itself, until it reaches the server.

[0157] S840: When the server triggers a control instruction based on the building control logic according to the collected data, a downlink Modbus TCP message including the control instruction is sent to the second DDC controller.

[0158] The process of the server sending the downlink Modbus TCP message to the second DDC controller is the same as the process of the server sending the downlink Modbus TCP message containing the acquisition instruction to the first DDC controller, which will not be repeated here.

[0159] S850: The second DDC controller receives the downlink Modbus TCP message including the control instruction, and enables the second field device to perform a corresponding action through the corresponding IO port in the IO input / output module corresponding to the logical address in the message.

[0160] Note that the above are only preferred embodiments of the present application and the technical principles used. Those skilled in the art will understand that the present application is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present application. Therefore, although the present application is described in more detail through the above embodiments, the present application is not limited to the above embodiments, and may also include more other equivalent embodiments without departing from the concept of the present application, all of which belong to the scope of protection of the present application.

Claims

1. A building control system based on cascade links, characterized in that: include: A server and several DDC controllers, each DDC controller is provided with two network ports, the two network ports of each DDC controller are connected to different DDC controllers, and are used to realize a chain cascade between the DDC controllers, wherein the DDC controller at the head end of the chain cascade is connected to the server; The DDC controller is used to receive the message sent by the server in the downstream direction of the chain cascade, forward the message that is not processed by the DDC controller locally to other DDC controllers in the system in the chain cascade, receive the message that is processed by the DDC controller locally and process it locally; The IO input and output module connected to the DDC controller is used to collect field data from the field equipment under the control of the DDC controller, or report the collected field status data to the DDC controller, or execute the action of controlling the field equipment.

2. The system according to claim 1, characterized in that: The DDC controller is also used to receive messages carrying field data sent by other DDC controllers from the upstream direction of the chain cascade, and send them to the server through the upstream direction of the chain cascade, or send the field data collected from the field equipment by the IO input and output module connected to the local machine to the server in the upstream direction of the chain cascade.

3. The system according to claim 1, characterized in that: The two network ports of each DDC controller are configured in one VLAN, and the VLAN of each DDC controller is different.

4. The system according to claim 1, characterized in that: Each DDC controller includes a DDC-M switching module and a DDC-P control module; The DDC-M switching module of each DDC controller is used to realize the interaction between the DDC controller and the server through the chain cascade, forward the messages that are not processed by the DDC controller in the chain cascade, and transfer the local messages to the local DDC-P control module; The DDC-P control module of each DDC controller is used to collect field data from the field device and / or send control commands to the field device according to the command of the message after receiving the message forwarded by the DDC-M switching module of the local device.

5. The system according to claim 4, characterized in that: The DDC-M switching module of each DDC controller is configured with the two network ports of the DDC controller and a third network port connected to the DDC-P control module of the DDC controller, and the IP address of the third network port is different from the IP addresses of the two network ports of the DDC controller; The DDC-P control module of each DDC controller is used to connect the IO input and output modules.

6. The system according to claim 4, characterized in that: The DDC-M switching module of each DDC controller is also used to receive messages carrying field data sent by other DDC controllers in the upstream direction of the chain cascade, and send them to the server through the upstream direction of the chain cascade, or send the field data collected from the field equipment by the IO input and output module connected to the local machine to the server in the upstream direction of the chain cascade.

7. The system according to claim 3, characterized in that: The DDC-M of each DDC controller is also used to update the MAC forwarding table entries in the chain cascade through MAC address learning and aging during the message forwarding process.

8. The system according to claim 3, characterized in that: The DDC-M of each DDC controller is also used to statically configure the MAC forwarding table entries in the chain cascade.

9. The system according to claim 1, characterized in that: Each DDC controller interacts with the IOM module it is connected to via the AUTBUS bus; The server and the DDC controllers, and the DDC controllers interact with each other via Modbus TCP messages.

10. A building control method, characterized in that: Using the system described in any one of claims 1 to 9 for control, comprising: The DDC controller of the system receives messages sent by the server of the system in the downstream direction of the chain cascade, forwards messages that are not processed by the DDC controller locally to other DDC controllers in the system in the chain cascade, and receives messages that are processed by the DDC controller locally and processes them locally; The IO input / output module connected to the DDC controller collects field data from field devices, or reports the collected field data to the DDC controller, or executes actions to control field devices under the control of the DDC controller.

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