Method for integrating energy management system and PLC (programmable logic controller) system to accurately control feeding quantity

Abstract

The invention belongs to the technical field of coking dedusting ash blending, and particularly relates to a method for integrating an energy management system and a PLC system to achieve accurate control over the feeding amount. Comprising the following steps: (1) establishing a communication loop: establishing a communication loop of a PLC system, an energy management system and an on-site weighing secondary meter, transmitting data of the on-site weighing secondary meter to the energy management system and the PLC system through the communication loop, and displaying the data in the PLC system and on a monitoring picture of an energy management network in real time; (2) data integration: the energy management system and the PLC system record, store, count and analyze data; and (3) the feeding amount is automatically adjusted, wherein a PLC system is matched with a PID controller to accurately control the rotating speed of the coal feeder. According to the invention, the data in the weighing secondary table is successfully introduced into the production system and the management system, the operation management mode of the production network and the management network is satisfied, and a solid foundation is laid for accurate recovery of the dedusting ash.

Description

Technical Field

[0001] The present invention belongs to the technical field of coking dust recycling, and in particular to a method for integrating an energy management system with a PLC system to achieve precise control of a feed rate. Background Art

[0002] Affected by the market environment of the coking industry and increasingly fierce competition within the industry, coking enterprises are often in a state of coal-coke inversion. Realizing accurate return of dust, reducing the cost of coal entering the furnace, and increasing the metallurgical coke rate and raising the price of coke have become two important measures for enterprises to reduce costs and increase efficiency.

[0003] The environmental dust ash return spiral scale and coal-loading dust ash return spiral scale of coking enterprises are important equipment for dust ash weighing and measurement. However, the dust ash data is only displayed in the secondary instrument between the cabinets. It is impossible to realize the automatic collection and tracking of weighing data, in-depth analysis of operation data and precise control of proportioning experiments, and it is even more impossible to automatically generate daily and monthly reports, making fine control difficult. Summary of the invention

[0004] The purpose of the present invention is to provide a method for integrating an energy management system and a PLC system to achieve accurate control of feed rate, so as to solve the problems existing in the prior art.

[0005] The technical solution adopted by the present invention to solve its technical problem is:

[0006] The method of integrating the energy management system with the PLC system to achieve accurate control of the feeding amount includes the following steps:

[0007] (1) Build a communication loop: Build a communication loop between the PLC system, energy management system and on-site weighing secondary meter. The data of the on-site weighing secondary meter is transmitted to the energy management system and PLC system through the communication loop, and is displayed in real time on the monitoring screen of the PLC system and the energy management network.

[0008] (2) Data integration: Energy management system and PLC system record, store, count and analyze data;

[0009] (3) Automatically adjust the feed rate: The PLC system cooperates with the PID controller to accurately control the speed of the coal feeder.

[0010] Furthermore, the method for establishing the communication circuit in step (1) is as follows:

[0011] 2.1. The weighing secondary meter on site includes the environmental dust removal ash return spiral weighing secondary meter and the coal loading dust removal ash return spiral weighing secondary meter, model SA-201H. The 4-20mA signal output terminal (17, 18) on the back of the weighing secondary meter is connected to the AI ​​communication card of the Siemens controller of the PLC system through the signal cable;

[0012] 2.2. Find the 485 communication terminal (13, 14) of the weighing secondary meter, connect them to the B port and A port of the RTUCOM terminal through the communication cable, connect the pigtail on the RTU to the optical cable in the optical fiber box through the optical fiber transceiver, and transmit the signal to the energy management center room through this optical cable;

[0013] 2.3. In the energy management center room, the laid optical cable is connected to the optical transceiver through the pigtail in the optical fiber box, and then the network cable on the optical fiber transceiver transmits the signal to the core switch of the energy management network;

[0014] 2.4. Set the baud rate of the weighing secondary meter to 5=9600, the instrument number to 01 and 02, and the RTU transmission cumulative amount to 2. Do not set it to pulse.

[0015] Furthermore, the method for data integration in step (2) is:

[0016] The energy management system and PLC system calculate the stage cumulative value based on the instantaneous value and cumulative value in the weighing secondary table, and generate daily reports, monthly reports, instantaneous flow trend charts, and stage cumulative trend charts based on the instantaneous value and stage cumulative value;

[0017] The production data of the weighing secondary table is saved through the storage function of the energy management system and the PLC system, and the data is queried through the query function of the energy management system and the PLC system.

[0018] Furthermore, the calculation method of the stage cumulative value is:

[0019] The energy management system and PLC system retrieve the cumulative value W(t) of the weighing secondary table through the communication loop, in units of t, and create three temporary variables Data_1, Data_2, and Q_total. The real-time cumulative value W(t) currently read is assigned to Data_1, and the cumulative value W(t) recorded and saved at the beginning of the stage is assigned to Data_2. The value of Data_1-Data_2 is assigned to Q_total, and the assigned Q_total is the cumulative value of the stage.

[0020] Furthermore, the specific method for automatically adjusting the feeding amount in step (3) is:

[0021] 3.1. The PID controller calculates the deviation e(t) according to the target feed rate Q_set and the instantaneous value Q(t) of the weighing secondary table, e(t) = Q_set-Q(t), and adjusts the speed setting value N_set of the coal feeder through the combination of the three links of proportion (P), integration (I) and differentiation (D);

[0022] Proportional link: P_out = Kp*e(t), where Kp is the proportional gain and P_out is the proportional output value;

[0023] Integral link: I_out = Ki*∫e(t)dt, where Ki is the integral gain and I_out is the integral output value;

[0024] Differential link: D_out = Kd*(e(t)-e(t-Δt)) / Δt, where Kd is the differential gain and D_out is the differential output value;

[0025] Total control output: N_set = N_base + P_out + I_out - D_out, where N_base is the basic speed setting value;

[0026] 3.2. The PLC system adjusts the speed of the coal feeder according to the speed setting value N_set output by the PID controller;

[0027] 3.3. Steps 3.1-3.2 are continuously performed in the cyclic scanning of the PLC system to ensure that the feeding amount is always maintained within the set range.

[0028] The present invention has the following beneficial effects:

[0029] 1. The present invention successfully introduces the data in the weighing secondary table into the production system and management system, realizes the simultaneous monitoring and display of the PLC system, energy management system and on-site weighing secondary table, and realizes the precise control of the feeding amount of the coal feeder, which meets the operation and management mode of production network + management network, and lays a solid foundation for the precise return of dust.

[0030] 2. Realize the function of automatically adjusting the feeding amount, so that the instantaneous feeding flow rate and the stage cumulative amount of coal are kept within the range required by the user, and realize fine control of the system.

[0031] 3. Operation data can be displayed in real time through various terminals such as production computers, mobile phones, tablets, laptops, office desktop computers, etc., making it easy to understand the production status. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the communication circuit structure of the present invention. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments and drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0034] like Figure 1 As shown, the method of integrating the energy management system and the PLC system to achieve accurate control of the feeding amount includes the following steps:

[0035] (1) Build a communication loop: Build a communication loop between the PLC system, energy management system and on-site weighing secondary meter. The data from the on-site weighing secondary meter is transmitted to the energy management system and PLC system through the communication loop, and is displayed in real time on the monitoring screen of the PLC system and the energy management network.

[0036] The communication circuit is constructed as follows:

[0037] 2.1. The weighing secondary meter on site includes the environmental dust removal ash return spiral weighing secondary meter and the coal loading dust removal ash return spiral weighing secondary meter, model SA-201H. The 4-20mA signal output terminal (17, 18) on the back of the weighing secondary meter is connected to the AI ​​communication card of the Siemens controller of the PLC system through the signal cable;

[0038] 2.2. Find the 485 communication terminal (13, 14) of the weighing secondary meter, connect them to the B port and A port of the RTUCOM terminal through the communication cable, connect the pigtail on the RTU to the optical cable in the optical fiber box through the optical fiber transceiver, and transmit the signal to the energy management center room through this optical cable;

[0039] 2.3. In the energy management center room, the laid optical cable is connected to the optical transceiver through the pigtail in the optical fiber box, and then the network cable on the optical fiber transceiver transmits the signal to the core switch of the energy management network;

[0040] 2.4. Set the baud rate of the weighing secondary meter to 5=9600, the instrument number to 01 and 02, and the RTU transmission cumulative amount to 2. Do not set it to pulse.

[0041] (2) Data integration: The energy management system and PLC system record, store, count and analyze data.

[0042] The energy management system and PLC system are the existing production management systems of the coking enterprise. The PLC system is the production control network (intranet) of the coking enterprise, and the energy management system is the energy management network (extranet) of the coking enterprise. The PLC system is located in the on-site cabinet room, and the energy management system is located in the energy management center computer room. The energy management system is equipped with a monitoring system for monitoring the production process. Both the energy management system and the PLC system have displays for real-time display of data, monitoring images, etc.

[0043] Both the energy management system and the PLC system can generate daily and monthly reports, and generate various trend charts based on production data. The energy management system and the PLC system are equipped with databases, data storage devices and other related equipment to provide query functions. The energy management system can connect to multiple terminals, such as production computers, mobile phones, tablets, laptops, office desktop computers, etc., and you can query and view relevant data by logging into the energy management system page on the terminal.

[0044] The energy management system and PLC system calculate the stage cumulative value based on the instantaneous value and cumulative value in the weighing secondary table, and generate daily reports, monthly reports, instantaneous flow trend charts, and stage cumulative trend charts based on the instantaneous value and stage cumulative value.

[0045] The production data of the weighing secondary table is saved through the storage function of the energy management system and the PLC system, and the data is queried through the query function of the energy management system and the PLC system.

[0046] The calculation method of the stage cumulative value is:

[0047] The energy management system and PLC system retrieve the cumulative value W(t) of the weighing secondary table through the communication loop, in units of t, and create three temporary variables Data_1, Data_2, and Q_total. The real-time cumulative value W(t) currently read is assigned to Data_1, and the cumulative value W(t) recorded and saved at the beginning of the stage is assigned to Data_2. The value of Data_1-Data_2 is assigned to Q_total, and the assigned Q_total is the cumulative value of the stage.

[0048] Taking 1 hour as a stage as an example, the energy management system and PLC system calculate every hour, and the cumulative value at the beginning of 1 hour minus the cumulative value at the end of 1 hour is the stage cumulative value of 1 hour. Similarly, taking 24 hours as a stage, the daily stage cumulative value is obtained, and taking one month as a stage, the monthly stage cumulative value is obtained. The calculated stage cumulative value is recorded in the corresponding daily report and monthly report for easy viewing.

[0049] (3) Automatically adjust the feed rate: The PLC system cooperates with the PID controller to accurately control the speed of the coal feeder.

[0050] The specific method of automatically adjusting the feeding amount is:

[0051] 3.1. The PID controller calculates the deviation e(t) according to the target feed rate Q_set and the instantaneous value Q(t) of the weighing secondary table, e(t) = Q_set-Q(t), and adjusts the speed setting value N_set of the coal feeder through the combination of the three links of proportion (P), integration (I) and differentiation (D);

[0052] Proportional link: P_out = Kp*e(t), where Kp is the proportional gain and P_out is the proportional output value;

[0053] Integral link: I_out = Ki*∫e(t)dt, where Ki is the integral gain and I_out is the integral output value;

[0054] Differential link: D_out = Kd*(e(t)-e(t-Δt)) / Δt, where Kd is the differential gain and D_out is the differential output value;

[0055] Total control output: N_set = N_base + P_out + I_out - D_out, where N_base is the basic speed setting value.

[0056] The target feeding amount Q_set is a set value and can be set according to actual conditions.

[0057] 3.2. The PLC system adjusts the speed of the coal feeder according to the speed setting value N_set output by the PID controller;

[0058] 3.3. Steps 3.1-3.2 are continuously performed in the cyclic scanning of the PLC system to ensure that the feeding amount is always maintained within the set range.

[0059] The above embodiments are only for describing the preferred implementation of the present invention, and are not intended to limit the concept and scope of the present invention. Without departing from the design concept of the present invention, various modifications and improvements made by ordinary persons in the art to the technical solution of the present invention should fall within the protection scope of the present invention.

[0060] The techniques, shapes, and structural parts not described in detail in the present invention are all well-known techniques.

Claims

1. A method for integrating an energy management system with a PLC system to achieve accurate control of feed quantity, characterized in that: The following steps are involved: (1) Build a communication loop: Build a communication loop between the PLC system, energy management system and on-site weighing secondary meter. The data of the on-site weighing secondary meter is transmitted to the energy management system and PLC system through the communication loop, and is displayed in real time on the monitoring screen of the PLC system and the energy management network. (2) Data integration: Energy management system and PLC system record, store, count and analyze data; (3) Automatically adjust the feed rate: The PLC system cooperates with the PID controller to accurately control the speed of the coal feeder.

2. The method for integrating energy management system and PLC system to realize accurate control of feeding amount according to claim 1, characterized in that: The method for building the communication circuit in step (1) is: a. The weighing secondary meter on site includes the environmental dust removal ash return spiral weighing secondary meter and the coal loading dust removal ash return spiral weighing secondary meter, model SA-201H. The 4-20mA signal output terminal (17, 18) on the back of the weighing secondary meter is connected to the AI ​​communication card of the Siemens controller of the PLC system through a signal cable; b. Find the 485 communication terminal (13, 14) of the weighing secondary meter, connect them to the B port and A port of the RTUCOM terminal through the communication cable, connect the pigtail on the RTU to the optical cable in the optical fiber box through the optical fiber transceiver, and transmit the signal to the energy management center room through this optical cable; c. In the energy management center computer room, the laid optical cable is connected to the optical transceiver through the pigtail in the optical fiber box, and then the network cable on the optical fiber transceiver transmits the signal to the core switch of the energy management network; d. Set the baud rate of the weighing secondary meter to 5=9600, the instrument number to 01 and 02, and the RTU transmission cumulative amount to 2. Do not set it to pulse.

3. The method for integrating energy management system and PLC system to realize accurate control of feeding amount according to claim 1, characterized in that: The method for data integration in step (2) is: The energy management system and PLC system calculate the stage cumulative value based on the instantaneous value and cumulative value in the weighing secondary table, and generate daily reports, monthly reports, instantaneous flow trend charts, and stage cumulative trend charts based on the instantaneous value and stage cumulative value; The production data of the weighing secondary table is saved through the storage function of the energy management system and the PLC system, and the data is queried through the query function of the energy management system and the PLC system.

4. The method for integrating energy management system and PLC system to realize accurate control of feeding amount according to claim 3 is characterized in that: The calculation method of the cumulative value of the stage is: The energy management system and PLC system retrieve the cumulative value W(t) of the weighing secondary table through the communication loop, in units of t, and create three temporary variables Data_1, Data_2, and Q_total. The real-time cumulative value W(t) currently read is assigned to Data_1, and the cumulative value W(t) recorded and saved at the beginning of the stage is assigned to Data_2. The value of Data_1-Data_2 is assigned to Q_total, and the assigned Q_total is the cumulative value of the stage.

5. The method for integrating energy management system and PLC system to realize accurate control of feeding amount according to claim 1, characterized in that: The specific method of automatically adjusting the feeding amount in step (3) is: I. The PID controller calculates the deviation e(t) according to the target feed rate Q_set and the instantaneous value Q(t) of the weighing secondary table, e(t) = Q_set-Q(t), and adjusts the speed setting value N_set of the coal feeder through the combination of the three links of proportion (P), integration (I), and differentiation (D); Proportional link: P_out = Kp*e(t), where Kp is the proportional gain and P_out is the proportional output value; Integral link: I_out = Ki*∫e(t)dt, where Ki is the integral gain and I_out is the integral output value; Differential link: D_out = Kd*(e(t)-e(t-Δt)) / Δt, where Kd is the differential gain and D_out is the differential output value; Total control output: N_set = N_base + P_out + I_out - D_out, where N_base is the basic speed setting value; II. The PLC system adjusts the speed of the coal feeder according to the speed setting value N_set output by the PID controller; III. Steps I-II are continuously performed in the cyclic scanning of the PLC system to ensure that the feeding amount is always maintained within the set range.

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