A centralized control system for heat exchange stations based on MQTT protocol

Abstract

The utility model discloses a centralized control system for a heat exchange station based on the MQTT protocol, including a power unit and a communication bus; the power unit includes a motor drive unit and a control unit, the motor drive unit collects motor information and transmits it to the power drive system; the communication bus is connected to the control unit; there are multiple control units, each control unit collects information from sensors in its corresponding control area and performs data processing, and shares the data to the communication bus through the MQTT protocol. The utility model eliminates the data acquisition cabinet in the centralized control system of the heat exchange station, reduces the equipment procurement cost, integrates the data acquisition and data sending functions into the power unit, realizes energy conservation and emission reduction, cost reduction and efficiency improvement, unattended operation, and MQTT protocol data reporting.

Description

Technical Field

[0001] The utility model relates to the technical field of heating systems, and more specifically to a heat exchange station centralized control system based on the MQTT protocol. Background Art

[0002] The heat exchange station is an important part of the urban centralized heating system. The heat exchange station is the last power center that transmits the heat from the urban centralized heating center to the user. A large number of motors, pumps, sensors, etc. are arranged in each heat exchange station. Each heat exchange station requires a stable, advanced and practical control and data set system to support the efficient operation of the heat exchange station and realize unmanned operation, and ultimately achieve energy conservation, emission reduction, cost reduction and efficiency improvement.

[0003] At present, the components of heat exchange station control systems on the market are basically the same, and they all consist of two parts, namely the power unit and the data acquisition and reporting system;

[0004] The power unit is divided into two parts: the motor drive unit and the control unit. The function of the motor drive unit is to convert electrical energy into rotational mechanical energy, that is, the rotating water pumps. These water pumps realize the secondary network water circulation and secondary network water replenishment. The water pumps are driven by variable frequency speed control devices. These variable frequency devices have intelligent characteristics and are equipped with DI, DO, AI, AO and communication interfaces; the control unit is mainly an intelligent controller that integrates CUP, DI, DO, AI, AO units and communication interfaces. It can be a single-chip microcomputer or a logic controller. The control unit is powerful, but it only plays the role of PID regulation in the original system.

[0005] The data collection and reporting system also integrates the intelligent controllers of CUP, DI, DO, AI, and AO units, which mainly collect data from the power drive system and sensor data, perform edge computing, and report the calculation results to the centralized control center in the form of DTU.

[0006] This conventional system composition has the following defects: 1. A separate data acquisition system needs to be set up, which is manifested on site as setting up a data acquisition cabinet, increasing procurement cost, installation cost, installation space, and installation period; 2. The motor drive unit and control unit in the on-site power unit themselves integrate the logic controller and have rich computing power, which can completely solve the problems of edge computing and data aggregation and reporting. Adding extra data collection cabinets is equivalent to wasting computing power; 3. The system composition is not flexible, and different sizes of thermal stations need to match different data collection cabinets; 4. This type of collection cabinet mostly reports data point-to-point or point-to-multipoint, and cannot realize the functions of Internet of Things topic subscription and topic publishing.

[0007] Therefore, how to provide a hot swap station centralized control system based on the MQTT protocol that does not require a data acquisition cabinet, eliminate the data acquisition cabinet, distribute its functions to the motor drive unit and control unit of each power unit, and realize multi-point data sharing is a problem that technical personnel in this field urgently need to solve. Utility Model Content

[0008] In view of this, the utility model provides a hot swap station centralized control system based on the MQTT protocol, aiming to solve the above technical problems.

[0009] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0010] A heat exchange station centralized control system based on the MQTT protocol, comprising a power unit and a communication bus;

[0011] The power unit includes a motor drive unit and a control unit, and the motor drive unit collects motor information and transmits it to the power drive system;

[0012] The communication bus is communicatively connected to the control unit; there are multiple control units, each of which collects information from sensors in its corresponding control area and performs data processing, and shares the data to the communication bus through the MQTT protocol.

[0013] The beneficial effect of the above technical solution is that the data collection and data transmission functions of the heat exchange station are integrated into the power unit, the motor drive unit automatically collects motor information and transmits it to the power drive system through the bus, the control unit realizes constant pressure or constant pressure difference water supply, and at the same time, the information transmitted by the power unit and the sensor information are processed as island data, and the processed data are packaged and shared on the communication bus.

[0014] Preferably, the control unit is a PLC or a single chip microcomputer.

[0015] Preferably, the control unit performs PID regulation, collects pressure signals, performs internal calculations, outputs voltage or current signals, controls the motor drive unit, and finally realizes constant pressure or constant pressure difference water supply.

[0016] Preferably, the control unit collects information from the sensors in the corresponding control area, including temperature, pressure, flow rate, and liquid level.

[0017] Preferably, the motor drive unit is a frequency converter or a soft starter.

[0018] Preferably, the motor information includes motor speed, motor current, motor voltage and motor temperature.

[0019] Preferably, the power units are provided in plurality, the plurality of the power units are connected in communication in parallel, and the plurality of the power units connected in communication in parallel are connected in series to the communication bus.

[0020] It can be seen from the above technical solution that compared with the prior art, the utility model discloses a heat exchange station centralized control system based on the MQTT protocol, which significantly reduces the equipment procurement cost by 35%; significantly reduces the construction period; the data collection of the centralized control center is significantly enriched; and the reasonable transmission protocol and network bus structure provide more possibilities for later function expansion. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0022] Figure 1 A schematic diagram of the structure of the centralized control system provided by the utility model;

[0023] Figure 2 This is a schematic diagram of the power unit principle provided by the utility model.

[0024] in,

[0025] 1- Power unit; 2- Motor drive unit; 3- Control unit; 4- Sensor; 5- Communication bus. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0027] The embodiment of the utility model discloses a heat exchange station centralized control system based on the MQTT protocol. Compared with the traditional heat exchange station centralized control system, the data acquisition cabinet is cancelled, and the data acquisition and data sending functions are integrated into the power unit, ultimately achieving energy saving and emission reduction, cost reduction and efficiency improvement, unattended operation, and the effect of MQTT protocol data reporting, including a power unit 1 and a communication bus 5;

[0028] The power unit 1 includes a motor drive unit 2 and a control unit 3. The motor drive unit 2 collects motor information and transmits it to the power drive system;

[0029] The communication bus 5 is communicatively connected with the control unit 3; there are multiple control units 3, each control unit 3 collects information from the sensor 4 in the control area corresponding to it and processes the data, and shares the data to the communication bus 5 through the MQTT protocol.

[0030] The MQTT protocol (Message Queuing Telemetry Transport) is an instant messaging protocol developed by IBM that can connect almost all networked objects to the outside world. It is a communication protocol used as a sensor and actuator, providing real-time and reliable messaging services for connected remote devices with very little code and limited bandwidth.

[0031] In order to further optimize the above technical solution, the control unit 3 is a PLC or a single-chip microcomputer, which mainly realizes the original basic function, namely PID regulation (collecting pressure signals, performing internal calculations, outputting voltage or current signals, controlling the motor drive unit, and finally realizing constant pressure or constant pressure difference water supply). The control unit uses a large amount of redundant computing power to collect the temperature, pressure, flow, liquid level and other sensor 4 information in the corresponding control area, and at the same time processes the information transmitted from the power unit bus and the sensor information as island data, and the processed data is packaged and shared on the communication bus.

[0032] In order to further optimize the above technical solution, the motor drive unit 2 is a frequency converter or soft starter, which can automatically collect up to hundreds of information such as motor speed, motor current, motor voltage, motor temperature, etc., and transmit them to the control unit of the power drive system through the bus.

[0033] In order to further optimize the above technical solution, a plurality of power units 1 are provided, the plurality of power units 1 are communicated in parallel, and the plurality of power units 1 communicated in parallel are connected in series to the communication bus 5 .

[0034] A heat exchange station has N power units, all of which share data on the bus. The control unit in one power unit will be automatically assigned as the site server, which reports and aggregates data through the MQTT protocol. Each power unit only collects data from the corresponding control interval and completes edge computing. The public interval data is fixedly collected in the first power unit (the first power unit is required for the heat exchange station, and the first power unit is configured with more public area I / O than other power systems at the same site).

[0035] The utility model cancels the setting of the data acquisition cabinet in the centralized control system of the heat exchange station, reducing the equipment procurement cost. After the data acquisition cabinet is cancelled, its functions are to be distributed to the motor drive unit and control unit of each power unit. This technology is not a simple addition and subtraction relationship. The key points are to solve the problems of computing power allocation, data reorganization, and network optimization. At the same time, it is necessary to improve the original solution's single data reporting and summarization method and the problem of being unable to realize multi-point data sharing.

[0036] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0037] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A centralized control system for heat exchange stations based on the MQTT protocol, characterized in that: It comprises a power unit (1) and a communication bus (5); The power unit (1) comprises a motor drive unit (2) and a control unit (3), wherein the motor drive unit (2) collects motor information and transmits it to a power drive system; The communication bus (5) is communicatively connected to the control unit (3); there are a plurality of control units (3), each of which collects information from a sensor (4) in a control area corresponding to it and performs data processing, and shares the data to the communication bus (5) via an MQTT protocol.

2. According to the MQTT protocol-based heat exchange station centralized control system of claim 1, it is characterized in that: The control unit (3) is a PLC or a single chip microcomputer.

3. According to claim 2, a heat exchange station centralized control system based on the MQTT protocol is characterized in that: The control unit (3) performs PID regulation.

4. According to the MQTT protocol-based heat exchange station centralized control system of claim 3, it is characterized in that: The control unit (3) collects information from the sensor (4) in the corresponding control area, including temperature, pressure, flow rate, and liquid level.

5. According to the MQTT protocol-based heat exchange station centralized control system of claim 1, it is characterized in that: The motor drive unit (2) is a frequency converter or a soft starter.

6. The heat exchange station centralized control system based on the MQTT protocol according to claim 5, characterized in that: The motor information includes motor revolutions, motor current, motor voltage and motor temperature.

7. The heat exchange station centralized control system based on the MQTT protocol according to claim 1, characterized in that: The power units (1) are provided in plurality, the plurality of the power units (1) are connected in communication in parallel, and the plurality of the power units (1) connected in communication in parallel are connected in series to the communication bus (5).

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