This article analyzes the large-scale application of Emerson CT converters in the metallurgical industry. According to different process requirements, different control methods are adopted to meet the on-site requirements, reflecting that Emerson CT has a wide range of application fields and strong applicability.
1 Introduction
China is a world-class steel country. China’s steel output of more than 300 million tons in the world for many years has made a huge contribution to the national economy in the era of reform and opening up. Since entering the "10th Five-Year Plan" national economic development plan, China has ushered in the period of high-quality and high-speed development of the heavy chemical industry. The metallurgical industry is used as an automation technology and electric power driving intensive industry. The application of frequency conversion drive technology has important industrial progress significance.
28,000 tons pellet production line case
2.1 Application Background
Anshan Baode Iron & Steel Co., Ltd. is a large iron and steel conglomerate with profile-oriented products. Baode Steel owns five branches of ironmaking, steelmaking, sintering, steel rolling, and oxygen production. It annually produces 1.2 million tons of iron and steel and 600,000 tons of steel. In order to adapt to market demand, it has expanded its own scale and built a new 800,000-ton/year pellet production line project. The main equipment of the newly-built pellet project adopts Emerson CT frequency converter as the core main drive system, which is combined with Siemens automation S7-400 PLC to form a complete control and drive system.
2.2 program determination
The project adopts two control methods: DCS system and on-site control. The control method is simple in the entire system, but it requires high vector control performance of the inverter. When configuring the frequency converter for the main motor of the rotary kiln, communicate with the user to obtain the motor parameters, the rated power = 250 KW, the rated current = 526 A, and the instantaneous maximum overload capacity is 180%. Taking into account the importance of the main equipment operation and must meet the user's technical specifications, the final selection of EV3500-4T3150P frequency converter as the main drive rotary kiln motor.
2.3 Process Equipment Introduction
The rotary kiln has a simple structure, convenient and reliable production process control, fewer wearing parts, high operation rate, and the main equipment for calcining pellets. It is also widely used in metallurgy, chemical engineering, construction and other industries. Baode's 800,000-ton/year pellet production line converter configuration is shown in Table 1.
Table 1 Bao Delta's 800,000-ton/year pellet production line converter configuration
name
model
Quantity
unit
Drive equipment
Inverter
EV3000-4T0900G
2
station
Roots blower
Inverter
EV3000-4T0300G
2
station
Roots blower
Inverter
EV3000-4T0022G
6
station
Stripping belt called motor
Inverter
EV3000-4T0550G
1
station
Grate motor
Inverter
EV3000-4T2000G
1
station
Ring cold host
Inverter
EV3500-4T3150P
3
station
Ring cooler
Inverter
EV3500-4T3150P
1
station
Rotary kiln main engine
Inverter
EV3000-4T0550G
2
station
Rotary kiln combustion fan
3 Vanadium Engineering Steelmaking District Case Study
3.1 Application Background
The steelmaking regional project of Chengde Steel's Vanadium Extraction Project is a new steelmaking blast furnace newly built by Chengde Steel Works with an annual production capacity of 4 million tons. Expanded the market share of main products in the market and increased the strength of their own brands. Emerson CT EV3000, EV3500 inverter in a large number of applications in the steel vanadium project steelmaking area, for the reliable operation of the relevant equipment escort.
3.2 EV3500 Application
Chenggang Vanadium Project Steelmaking Area Electric Complete Project: No. 1-4 oxygen gun high pressure water pump adopts Ai Shengsheng EV3500-4T4000P frequency converter, which is an important equipment for steel-making water supply. The on-site operation control method is SM-PROFIBUS-DP bus mode. In the past, oxygen gun high-pressure water supply was realized by high-voltage motors. Therefore, this design uses Ai Shengsheng EV3500 inverter and low-voltage inverter motor supporting the use. The main purpose: use EV3500 frequency converter and frequency conversion motor to replace the high voltage motor (because high pressure motor driven oxygen gun high pressure water pump control water pressure and head accuracy is not high).
(1) On-site configuration. The frequency converter EV3500-4T4000P drives 4 sets of 355kW frequency conversion motors. The auxiliary drive is a Siemens S7-400 PLC and is configured with 1 ET200 remote I/O substation. The system is configured with 3 devices and 1 device. The SM-PROFIBUS-DP bus is used to control the system. No matter whether it is on the side of the machine or automatically, it is controlled by the host computer. The operation is simple and convenient.
(2) Inverter bus communication control mode design. Using SM-PROFIBUS-DP communication control to achieve unattended operation, simple and convenient control line maintenance, low failure rate and failure point, meet the start and stop control of EV3500 inverter through DP cable, feedback of inverter running status, remote fault Reset and other requirements, and make full use of the powerful advantages of EV3500 communication. For the requirements of the control mode, the inverter cabinet is designed as follows: Each EV3500-4T4000P inverter is controlled by one main module and three SPMA1402 110/132kW slave modules. Optional 1 PROFIBUS bus interface module. This system uses the siemens S7 series PLC and Emerson CT EV3500 inverter communication, and provide the corresponding CTSP0672.GSD file configuration in the host computer application and sm_profibus_dp_user_guide.pdf file, as a command parsing table, and Communication connection between the PROFIBUS bus interface modules is controlled by sending the “control word†of the host computer and reading the “status word†of the inverter.
The extensive application of Emerson CT frequency converters in the steelmaking area of ​​the steelmaking project of Chengde Steel reflects the completeness of Emerson CT frequency converters from small power units to high power modular drives. It is used in all aspects of the metallurgical industry, Emerson CT. The other applications of the inverter EV2000 are shown in Table 2.
Table 2 EV2000 in the converter body, molten iron infusion station, bulk loader part of the frequency converter configuration table
name
model
Quantity
unit
Drive equipment
Inverter
EV2000-4T0110G
2
station
Converter front door fire door motor
Inverter
EV2000-4T0550G
3
station
Converter slag tanker
Inverter
EV2000-4T1100G
3
station
Iron tank walking motor
Inverter
EV2000-4T1320G
6
station
Mixed iron motor
Inverter
EV1000-4T0037G
70
station
Feeding motor
4 TD3300 Tension Inverter Retractable Volume Control System
4.1 Application Background
The wholly-owned foreign-funded project Tianjin Huayu Metal Materials Co., Ltd. plans to invest in 8 continuous galvanizing lines to produce and sell galvanized steel strips and other related products, becoming the largest galvanized narrow strip steel production base in the world. The hot-rolled sheet width of the Tianjin Huayu pickling line is 850mm and its thickness is 2.75-5mm. The system has high requirements on the tension. The TD3300 special tension inverter is used in conjunction with the EV3000 vector inverter to obtain a constant and stable tension during the crimping process. This is the first time that Emerson CT frequency converters have been used in coil tension open loop systems for large hot rolled coils. The on-site operation control method is the SM-PROFIBUS-DP bus method, which uses the rotary encoder as the feedback of the frequency converter to accurately calculate the coil diameter. Adopting the bus control scheme not only improves the accuracy of the control system, but also enhances the system stability.
4.2 Project Design
(1) Analysis of the tension system
· Although common frequency converters using speed difference to establish the tension system (speed build-up) can meet the control, the tension value is inaccurate. In the actual process, the tension roller and the curling shaft that drive the running of the plate are all active rollers, and require speed matching. High, when the speed deviation occurs, the plate will be wrinkled or eccentric, the plate curl will appear inconsistent, and the precision will be unstable.
· Tension meter is used to detect the system tension, the system control accuracy is high, and the whole process of the process requires close-loop tension control. The cost is high and the process is cumbersome, so it is not used.
· Tensile tension system is set up to establish the tension system at the same time when the coil is started. There is enough tension to make the sheet tight. The sheet is rolled at constant tension during the whole process. The tension roller is controlled by the SM-PROFIBUS-DP bus. The line speed output of AO1 is used as the line speed input of the coiler TD3300. Tension constant speed matching accuracy is highly recognized by the customer, enabling unattended operation and simple and convenient control line maintenance.
(2) pickling line system configuration. Ai Shengsheng TD3300-4T1320G tension control inverter and EV3000-4T0550G vector control inverter match the composition of the tension open-loop system, TD3300 used as a system drive motor winding machine and winder, EV3000 as the main part of the system. The crimper and uncoiler are variable frequency motors and are equipped with a rotary encoder. The auxiliary drive is implemented by a Siemens S7-400 PLC and configured with an ET200 remote I/O drop. The SM-PROFIBUS-DP bus communicates with the Emerson CT Bus Adapter TDS-PA01 to control the inverter. The operation is easy to control and precise. The pickling line system configuration is shown in Table 3.
Table 3 Pickling line frequency converter and corresponding motor configuration
name
model
Quantity
unit
Drive equipment
Inverter
EV3000-4T0550G
2
station
2-roll tension roller
Inverter
EV3000-4T0550G
2
station
5-roll straightening machine
Inverter
TD3300-4T1320G
2
station
Curl motor
Inverter
TD3300-4T1320G
4
station
Unwinding motor
Inverter
EV3000-4T0450G
6
station
Pull roller motor
Inverter
EV3000-4T0900P
4
station
Looper horizontal motor
Inverter
EV3000-4T0450P
4
station
Slot pinch roller motor
Inverter
EV3000-4T0900G
8
station
Looper transmission motor
(3) pickling line process. Pickling line process description: uncoiler - five roller straightening - head loop - pull roller - pickling tank - washing tank - drying - tail loop - 2 roll tension roller - -Winder. Pickling line process shown in Figure 1, Figure 2.
Figure 1 Uncoiler and head looper process
Figure 2 pickling and crimping process
5 Concluding remarks
Other large-scale applications of Emerson CT high-power frequency converters in the metallurgical industry include frequency conversion drive of Henan Wuyang Steel Belt Conveyor and high-power slurry pump. The system uses 27 sets of Emerson CT EV2000 frequency converter; Haicheng Houying Group Datun The steel mill SPM engineering machine is applied to the combustion furnace of the lime kiln. Anshan Haicheng Magnesium Mine employs a total of 25 EV2000 frequency converters for different loads such as magnesium ore rotary kiln, induced draft fan, and combustion air blower.
The application of Emerson CT frequency converter in Anshan Iron and Steel Group Co., Ltd. fully satisfies the requirements of the production technology and mechanical equipment, and shows the superior performance and high reliability of the frequency converter, which has been praised and praised by users. The extensive application of scaled examples reflects the maturity of Emerson CT frequency converters from low-power units to high-power modular drive technologies, demonstrating the brand integration advantages of large-scale drive technology vendors for large-scale industrial solutions.
References (slightly)
About the Author
Wang Junfang male engineer now works in the technical department of Anshan Xinhe Electric Co., Ltd. engaged in the design, commissioning and on-site service of inverters and low-voltage electrical appliances in the metallurgical industry.