CN112178753A - Intelligent heat supply controller and control method for heat exchange station with master-slave structure - Google Patents

Abstract

The invention relates to an intelligent heat supply controller of a heat exchange station with a master-slave structure and a control method. At present, a universal PLC (programmable logic controller) is used as a controller of a heat supply control system, and the universal controller consists of a plurality of modules, so that the controller is large in size, high in cost and complex in structure. The invention comprises the following components: the main control module is connected with the monitoring center through a communication interface, the main control module is connected with a primary network, the secondary network units are respectively and correspondingly connected with the primary control module and the secondary control module, the main control module is communicated with a local PC through RS232 and USB interfaces, the local LAN or a control network is communicated through Ethernet and an RS485 bus, the Internet is accessed through GPRS and the Ethernet, the main control module collects water supply temperature, water supply pressure, water supply flow, water return temperature and water return pressure primary network analog quantity, controls the openness of a primary network water supply valve and stores related data information. The invention is used for the intelligent heat supply controller of the heat exchange station with a master-slave structure.

Description

Intelligent heat supply controller and control method for heat exchange station with master-slave structure

The technical field is as follows:

the invention relates to the technical field of industrial control, in particular to an intelligent heat supply controller of a heat exchange station with a master-slave structure and a control method.

Background art:

the existing heat supply control system uses a general PLC (programmable logic controller) as a controller, and has no special controller, but the general PLC is composed of a plurality of modules, such as a power module, a CPU module, an AI module, an AO module, a DI module, a DO module, a communication module and the like, so that the controller has the defects of large volume, high cost and complex structure, and the control system with low cost, high cost performance and simple structure can not be designed according to the actual requirement of the heat supply control system. In addition, the PLC can only implement a relatively simple control algorithm, and cannot implement a high-precision complex control algorithm for the control quantity of the heat supply control system.

The invention content is as follows:

the invention aims to provide an intelligent heat supply controller of a heat exchange station with a master-slave structure and a control method thereof.

The above purpose is realized by the following technical scheme:

the utility model provides a heat exchange station intelligence heat supply controller of master slaver structure which constitutes includes: the system comprises a main control module and a group of slave control modules, wherein the main control module is connected with the group of slave control modules through a CAN bus, the main control module is connected with a monitoring center through a communication interface, the main control module is connected with a primary network, the group of slave control modules are correspondingly connected with a secondary network unit respectively, the main control module is communicated with a local PC through RS232 and USB interfaces, communicated with a local area network or a control network through an Ethernet and an RS485 bus and accessed into INTERNET through GPRS and the Ethernet, the main control module acquires water supply temperature, water supply pressure, water supply flow, water return temperature and water return pressure primary network analog quantity, controls primary network water supply valve opening and stores related data information, and the slave control modules acquire water supply temperature, water supply pressure, water supply flow, water return temperature, water return pressure secondary network analog quantity and pump running state, The digital quantity of the secondary network of the pump fault state controls the starting and stopping of the circulating pump and the water replenishing pump, and is communicated with the main control module through a CAN bus.

The master control module of the intelligent heat supply controller of the heat exchange station with the master-slave structure comprises an MCU1, the MCU1 is respectively connected with 5V/3.3V LDO, 2 four-channel digital isolation devices, an optical coupling isolation and level conversion circuit 1, a key, an LCD display module, EERPOM, an RTC circuit, an optical coupling isolation and level conversion circuit 2, 4 double-channel digital isolators and a PHY interface chip, the PHY interface chip is connected with an isolation transformer, 3 double-channel digital isolators are respectively connected with a GPRS module, a 232 interface circuit, a 485 interface circuit and a CAN interface circuit, the optical coupling isolation and level conversion circuit 2 is respectively connected with the relay output circuit and the triode output circuit, 2 four-channel digital isolation devices are respectively connected with the multi-channel D/A converter and the multi-channel A/D conversion module, the 5V/3.3V LDO is connected with the 24V/5V isolation power supply module.

The intelligent heat supply controller of the heat exchange station with the master-slave structure is characterized in that the slave control module comprises an MCU2, the MCU2 is respectively connected with the 5V/3.3V LDO, 2 four-channel digital isolation devices, the optical coupling isolation and level conversion circuit 1, the optical coupling isolation and level conversion circuit 2 and the double-channel digital isolator, the double-channel digital isolator is connected with the CAN interface chip, the optical coupling isolation and level conversion circuit 2 is connected with the relay output circuit, 2 four-channel digital isolation devices are respectively connected with the multi-channel D/A converter and the multi-channel A/D conversion module, and the 5V/3.3V LDO is connected with the 24V/5V isolation power module.

The heat exchange station intelligent heat supply controller with the master-slave structure and the multichannel D/A converter have the functions

The multi-channel A/D conversion module is realized by AD5676R chips and XTR111 chips, and the function of the multi-channel A/D conversion module is realized by ADS8688 chips.

An intelligent heat supply controller of a heat exchange station with a master-slave structure and a control method thereof are disclosed, the method comprises the following steps:

after the equipment is powered on, initializing the MCU and peripheral devices, reading system configuration parameters stored in the EEPROM, enabling a WATCHDOG timer WATCHDOG and a system time base, and entering a system main cycle program; in the main cycle, firstly, the MCU carries out key processing and an LCD module display interface, then inquires an interruption zone bit, carries out corresponding processing according to the type of the interruption zone bit, and processes acquisition of primary network analog quantity and digital quantity, acquisition of secondary network analog quantity and digital quantity and corresponding data transmission according to different time references, the MCU judges the limit values and the states of the acquired primary and secondary analog quantity AI and digital quantity DI, if the limit values or the states are abnormal, an alarm and fault diagnosis program is started, otherwise, PID operation is carried out on the acquired analog quantity and a control object, and corresponding control quantity AO/DO is output to a corresponding actuator; and finally, the system updates the state, saves the new state parameters to the EEPROM and clears the WATCHDOG timer WATCHDOG.

Has the advantages that:

1. the invention relates to a heat exchange station intelligent heat supply controller with a master-slave structure and a control method thereof.

The controller adopts a master-slave structure design aiming at the control of the heat exchange station, so that the equipment has low cost and high cost performance.

The heat supply controller provided by the invention is designed by adopting a master-slave structure control mode aiming at the characteristics of the heat exchange station, so that the cost of a control system is reduced, and the control precision of the system is improved.

The controller adopts the advanced multi-channel D/A converter and the multi-channel A/D converter, so that the sampling and conversion precision of the analog quantity is high, and the control effect of the heat supply controller is improved.

The controller adopts a PID control algorithm of fuzzy control, so that the system has high control precision and quick response, and overcomes the defects that the PLC in the prior art can only realize a simpler control algorithm and cannot realize a high-precision complex control algorithm aiming at the control quantity of a heat supply control system.

Description of the drawings:

FIG. 1 is a schematic of the topology of the present invention.

Fig. 2 is a schematic block diagram of a main control module in the present invention.

FIG. 3 is a schematic block diagram of a slave control module in the present invention.

Fig. 4 is a flow chart of the operation of the present invention.

The specific implementation mode is as follows:

example 1:

the utility model provides a heat exchange station intelligence heat supply controller of master slaver structure which constitutes includes: the system comprises a main control module and a group of slave control modules, wherein the main control module is connected with the group of slave control modules through a CAN bus, the main control module is connected with a monitoring center through a communication interface, the main control module is connected with a primary network, the group of slave control modules are correspondingly connected with a secondary network unit respectively, the main control module is communicated with a local PC through RS232 and USB interfaces, communicated with a local area network or a control network through an Ethernet and an RS485 bus and accessed into INTERNET through GPRS and the Ethernet, the main control module acquires water supply temperature, water supply pressure, water supply flow, water return temperature and water return pressure primary network analog quantity, controls primary network water supply valve opening and stores related data information, and the slave control modules acquire water supply temperature, water supply pressure, water supply flow, water return temperature, water return pressure secondary network analog quantity and pump running state, The digital quantity of the secondary network of the pump fault state controls the starting and stopping of the circulating pump and the water replenishing pump, and is communicated with the main control module through a CAN bus.

Example 2:

according to the heat exchange station intelligent heat supply controller with the master-slave structure described in embodiment 1, the master control module includes an MCU1, the MCU1 is respectively connected with a 5V/3.3V LDO, 2 four-channel digital isolators, an optocoupler isolation and level conversion circuit 1, a key, an LCD display module, an EERPOM, an RTC circuit, an optocoupler isolation and level conversion circuit 2, 4 dual-channel digital isolators, and a PHY interface chip, the PHY interface chip is connected with an isolation transformer, 3 dual-channel digital isolators are respectively connected with a GPRS module, a 232 interface circuit, a 485 interface circuit, and a CAN interface circuit, the optocoupler isolation and level conversion circuit 2 is respectively connected with a relay output circuit and a triode output circuit, 2 four-channel digital isolators are respectively connected with a multi-channel D/a converter and a multi-channel a/D conversion module, the 5V/3.3V LDO is connected with the 24V/5V isolation power supply module.

Example 3:

according to the heat exchange station intelligent heat supply controller with the master-slave structure in embodiment 2, the slave control module includes an MCU2, the MCU2 is connected with the 5V/3.3V LDO, 2 four-channel digital isolators, the optical coupling isolation and level conversion circuit 1, the optical coupling isolation and level conversion circuit 2, and the two-channel digital isolator, respectively, the two-channel digital isolator is connected with the CAN interface chip, the optical coupling isolation and level conversion circuit 2 is connected with the relay output circuit, 2 four-channel digital isolators are connected with the multi-channel D/a converter and the multi-channel a/D conversion module, respectively, and the 5V/3.3V LDO is connected with the 24V/5V isolation power module.

Example 4:

the heat exchange station intelligent heat supply controller with the master-slave structure according to embodiment 2, wherein the multi-channel D/A

The converter function is realized by AD5676R and XTR111 chips, the multichannel A/D conversion module function adopts ADS8688 chip to realize

Example 5:

a control method for an intelligent heat supply controller of a heat exchange station with a master-slave structure, which is described in embodiments 1 to 4, is characterized in that after equipment is powered on, an MCU and peripheral devices are initialized, system configuration parameters stored in an EEPROM are read, and then a WATCHDOG timer WATCHDOG and a system time base are enabled to enter a system master cycle program. In the main cycle, firstly, the MCU carries out key processing (keys are detected in an interruption mode) and an LCD module display interface, then, an interruption zone bit is inquired, corresponding processing is carried out according to the type (485 receiving interruption, 232 receiving interruption, Ethernet receiving interruption, GPRS receiving interruption and CAN receiving interruption) of the interruption zone bit, and acquisition of primary network analog quantity and digital quantity, acquisition of secondary network analog quantity and digital quantity and corresponding data transmission (485, 232, Ethernet, GPRS and CAN) are processed according to different time references, the MCU judges the limit values and the states of the acquired primary and secondary analog quantities AI and digital quantities DI, if the limit values or the states are abnormal, an alarm and fault diagnosis program is started, otherwise, PID operation is carried out on the acquired analog quantity and a control object, and corresponding control quantity AO/DO is output to a corresponding actuator. And finally, the system updates the state, saves the new state parameters to the EEPROM and clears the WATCHDOG timer WATCHDOG.

The intelligent heat supply controller of the heat exchange station with the master-slave structure has the technical scheme that the intelligent heat supply controller of the heat exchange station with the master-slave structure consists of a master control module and a slave control module, wherein the master control module is communicated with the slave control module through a CAN bus, as shown in attached figure 1;

the main control module completes the following functions: collecting primary network analog quantity, such as water supply temperature, water supply pressure, water supply flow, return water temperature, return water pressure and other physical quantity, and controlling the opening of a primary water supply valve; communicating with a slave control module through a CAN interface; communicating with a local PC through an RS232 and USB interface; the local area network or the control network is communicated with the Ethernet and the RS485 bus; the Internet is accessed through GPRS and Ethernet; saving related data information and the like;

the slave control module finishes acquisition of secondary network analog quantity, such as physical quantity and digital quantity of water supply temperature, water supply pressure, water supply flow, return water temperature, return water pressure and the like, such as pump running state, pump fault state and the like, and controls starting and stopping of a corresponding circulating pump and a water replenishing pump; the CAN bus is communicated with the main control module;

as shown in fig. 2, the main control module is composed of an MCU1, a 24V/5V isolation power module 2, a 5V/3.3V LDO3, a multi-channel a/D conversion module 4, a four-channel digital isolation device 5, an optical coupling isolation and level conversion circuit 6, a multi-channel D/a converter 7, an optical coupling isolation and level conversion circuit 8, a relay output circuit 9, a triode output circuit 10, a dual-channel digital isolator 11, a 485 interface circuit 12, a 232 interface circuit 13, a GPRS module 14, a PHY interface chip 15, an isolation transformer 16, a key 17, an LCD display module 18, an eer com 19, an RTC circuit 20 and a CAN interface circuit 21;

the main control module MCU1 is used as a core device of a heat supply controller, an STM32F107VCT6 ARM7 chip of ST company is selected, the chip is based on an ARM Cotex-M3 inner core, 72MHZ main frequency, 256K byte Flash and 64K byte SRAM are achieved, and the functions of acquisition, processing, output quantity control, communication, system control algorithm realization and the like of analog quantity and digital quantity are mainly realized; the 24V/5V Jinsheng Yang isolation power supply module 2 selects a URB2405-6W model, realizes that 24VDC is converted into 5VDC to supply power for the MCU peripheral module, and simultaneously realizes the isolation of an input power supply and a main control module power supply; the 5V/3.3V LDO3 adopts an AMS1117 power chip to convert 5VDC into 3.3VDC to supply power for the MCU 1; the multi-channel A/D conversion module 4 selects an ADS8688 eight-channel A/D converter of TI company, the input range can be set, the daisy chain form can be expanded, the acquisition of 8 paths of analog quantity is realized, the resolution is 16bit, the sampling rate can reach 1Msps, and the input of 0-5V voltage signals or 4-20 mA current signals can be selected; the four-channel digital isolation device 5 adopts ISO7341 to realize the isolation of the SPI bus; the optical coupling isolation and level conversion circuit 6 realizes the input of digital signals, level conversion and isolation of input signals from the MCU1 core control module; the multi-channel D/A converter 7 selects AD5676R, 16 bits and 8 channels of ADI company and a single-polarity voltage output DA conversion chip to convert multi-channel digital quantity into voltage analog quantity, can realize V/I conversion by externally connecting XTR111, and realizes output of 4-20 mA current analog quantity, thereby realizing that analog signals are 0-5V voltage signals and 0-20 mA current signals and can be selectively output; the optocoupler and level conversion circuit 8 is used for realizing the functions of isolating and converting the output digital quantity by using TLP 181; the relay output circuit 9 is driven by the ULN2003 to realize relay output; the triode output circuit 10 is used for realizing NPN (PNP) output by selecting a triode with proper driving capability; the dual-channel digital isolation device 11 selects ISO7221 to realize digital isolation of UART interfaces between the MCU1 and the peripheral interface module; the 485 interface circuit 12 selects MAX491 to realize the level conversion between UART and RS 485; 232 interface circuit 13, selecting MAX3232 to realize level conversion between UART and RS 232; the GPRS module 14 adopts a SIM800C module of SIMCOM company to realize the GPRS communication function; the PHY interface chip 15 and the isolation transformer 16 realize the Ethernet interface communication function, wherein the PHY interface chip is DP83848I interface chip of TI company; the keys 17 and the LCD display module 18 realize the functions of a man-machine interface, such as parameter setting, state parameter inquiry and the like; EERPOM19 is used to store relevant configuration parameters, and AT24C256 of ATMEL company is selected; the RTC circuit 20 selects PCF8563 to provide a real-time clock for the system; the CAN interface circuit 21 selects an SN65HV1050 chip and a related protection circuit to realize the CAN bus communication function with the slave control module;

as shown in fig. 3, the slave control module is composed of an MCU21, a 24V/5V isolation power supply module 2, a 5V/3.3V LDO3, a multi-channel a/D conversion module 4, a four-channel digital isolation device 5, an optical coupling isolation and level conversion circuit 6, a multi-channel D/a converter 7, an optical coupling isolation and level conversion circuit 8, a relay output circuit 9, a dual-channel digital isolator 10, and a CAN interface chip 11.

Selecting STM8S208 of ST company from the control module MCU21 to realize the functions of acquisition of secondary network input quantity and communication with the main control module; a 24V/5V isolation power supply module 2, wherein a Jinsheng Yang isolation power supply module URB2405-3W is selected; AMS1117 is selected as 5V/3.3V LDO 3; the multi-channel A/D conversion module 4 selects an ADS8688 eight-channel A/D converter of TI company to acquire 8-channel 0-5V voltage signals or 4-20 mA current signals; the four-channel digital isolation device 5 adopts ISO7341 to realize the isolation of the SPI bus; the optocoupler isolation and level conversion circuit 6 is used for realizing the isolation and level conversion function of the output digital quantity by using a TLP181 as an optocoupler; the multi-channel D/A converter 7 selects AD5676R, 16 bits and 8 channels of ADI company and a single-polarity voltage output DA conversion chip to convert multi-channel digital quantity into voltage analog quantity, can realize V/I conversion by externally connecting XTR111, and realizes output of 4-20 mA current analog quantity, thereby realizing that analog signals are 0-5V voltage signals and 4-20 mA current signals and can be selectively output; the optocoupler isolation and level conversion circuit 8 is used for realizing the isolation and level conversion function of the output digital quantity, wherein the optocoupler is TLP 181; the relay output circuit 9 is driven by the ULN2003 to realize relay output; the dual-channel digital isolator 10 selects ISO7221 to realize digital isolation of UART interfaces between the MCU2 and peripheral interface modules; the CAN interface chip 11 adopts an SN65HV1050 chip and a related protection circuit to realize the CAN bus communication function with the main control module.

Claims (5)

1. The utility model provides a heat exchange station intelligence heat supply controller of master slaver structure which constitutes includes: the system comprises a main control module and a group of slave control modules, and is characterized in that: the main control module is connected with a group of slave control modules through a CAN bus, the main control module is connected with a monitoring center through a communication interface, the main control module is connected with a primary network, the group of slave control modules are respectively correspondingly connected with a secondary network unit, the main control module is communicated with a local PC through RS232 and USB interfaces, is communicated with a local area network or a control network through an Ethernet and an RS485 bus, and is accessed into INTERNET through GPRS and the Ethernet, the main control module collects primary network analog quantities of water supply temperature, water supply pressure, water supply flow, water supply temperature, return water temperature and return water pressure, controls the opening degree of a primary network water supply valve, stores relevant data information, and the slave control module collects secondary network analog quantities of water supply temperature, water supply pressure, water supply flow, return water temperature and return water pressure, secondary network analog quantities of pump operation state and secondary network digital quantities of pump failure state, and the control system controls the starting and stopping of the circulating pump and the water replenishing pump and is communicated with the main control module through a CAN bus.

2. The intelligent heat supply controller of a heat exchange station with a master-slave structure as claimed in claim 1, wherein: the main control module comprises an MCU1, the MCU1 is respectively connected with a 5V/3.3V LDO, 2 four-channel digital isolation devices, an optical coupling isolation and level conversion circuit 1, a key, an LCD display module, an EERPOM, an RTC circuit, an optical coupling isolation and level conversion circuit 2, 4 double-channel digital isolators and a PHY interface chip, the PHY interface chip is connected with an isolation transformer, 3 double-channel digital isolators are respectively connected with a GPRS module, a 232 interface circuit, a 485 interface circuit and a CAN interface circuit, the optical coupling isolation and level conversion circuit 2 is respectively connected with the relay output circuit and the triode output circuit, 2 four-channel digital isolation devices are respectively connected with the multi-channel D/A converter and the multi-channel A/D conversion module, the 5V/3.3V LDO is connected with the 24V/5V isolation power supply module.

3. A heat exchange station intelligent heat supply controller of master-slave structure according to claim 2, characterized by: the slave control module comprises an MCU2, the MCU2 is respectively connected with the 5V/3.3V LDO, 2 four-channel digital isolators, the optical coupling isolation and level conversion circuit 1, the optical coupling isolation and level conversion circuit 2 and the double-channel digital isolator, the double-channel digital isolator is connected with the CAN interface chip, the optical coupling isolation and level conversion circuit 2 is connected with the relay output circuit, 2 four-channel digital isolators are respectively connected with the multi-channel D/A converter and the multi-channel A/D conversion module, and the 5V/3.3V LDO is connected with the 24V/5V isolation power module.

4. A heat exchange station intelligent heat supply controller of master-slave structure according to claim 2 or 3, characterized by: the function of the multi-channel D/A converter is realized by AD5676R and XTR111 chips, and the function of the multi-channel A/D conversion module is realized by ADS8688 chips.

5. A control method of a heat exchange station intelligent heat supply controller with a master-slave structure as claimed in claims 1-4, characterized in that: the method comprises the following steps:

after the equipment is powered on, initializing the MCU and peripheral devices, reading system configuration parameters stored in the EEPROM, enabling a WATCHDOG timer WATCHDOG and a system time base, and entering a system main cycle program; in the main cycle, firstly, the MCU carries out key processing and an LCD module display interface, then inquires an interruption zone bit, carries out corresponding processing according to the type of the interruption zone bit, and processes acquisition of primary network analog quantity and digital quantity, acquisition of secondary network analog quantity and digital quantity and corresponding data transmission according to different time references, the MCU judges the limit values and the states of the acquired primary and secondary analog quantity AI and digital quantity DI, if the limit values or the states are abnormal, an alarm and fault diagnosis program is started, otherwise, PID operation is carried out on the acquired analog quantity and a control object, and corresponding control quantity AO/DO is output to a corresponding actuator; and finally, the system updates the state, saves the new state parameters to the EEPROM and clears the WATCHDOG timer WATCHDOG.

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