Scheme Design of Control System for Fracturing Truck
- Commodity name： Scheme Design of Control System for Fracturing Truck
- Product Description
1Overall design thought
The fracturing truck control system is based on CANBus communication is the core control system. The system adopts vehicle-level PLUS +1 controller, with analog acquisition port and analog output port. The analog acquisition accuracy is 12 bits of hardware, which can directly acquire voltage signal, resistance signal, current signal and frequency signal. The analog output port is also 12 bits of hardware, which can output current value, duty ratio value and voltage value. Its driving capability can reach 3A and has closed-loop feedback, the control accuracy is very high, the current control accuracy is 0.1mA, and the voltage control accuracy is 0.01. These excellent characteristics can be directly adapted to various sensors on site and can be adapted to various brands of hydraulic systems. The working temperature range of -40~70 ℃ is much higher than the working temperature range of the existing control system. The control system designed based on PLUS +1 is simpler, more reasonable and has higher indexes, with high flexibility and reliability, it is the future development direction of fracturing truck controller system.
MORE 1The control system has a wealth of control instructions, through the real-time data acquisition and control of the system, can complete data verification, data management, alarm monitoring and data transmission and other functions.
2Introduction to System
Fracturing operations refer to the use of multiple fracturing trucks,The mixed fluid mixed by the sand mixer is injected into the bottom of the well from the wellhead to form or expand cracks to improve oil and gas recovery. Each fracturing pump truck under construction transmits control and display signals to the instrument truck through a multi-core connecting cable, and starts and controls the throttle, gear shift, pressure and displacement display, overpressure reset, etc. of multiple fracturing pump trucks through a centralized control panel located in the instrument truck. The density, displacement, various additives and pressure signals of the sand mixer and the manifold are transmitted to the instrument car for data collection and monitoring through the connecting cable. In order to meet the construction process requirements, especially in the large sand ratio operation, multi-vehicle cooperative operation, data sharing, reasonable and effective automatic control system is especially important. The actuators of the sand mixer and fracturing truck can be controlled in the instrument car to ensure that the construction process requirements are met.
Control flow of fracturing unit is shown in Fig. 1shown.
Use Danfoss Danfoss PLUS 1The controller can efficiently share the data of each vehicle, and is compatible with the vehicle's engine bus and gearbox bus, which greatly improves the real-time and reliability of the control.
3 CANbus technology
CAN 是Controller Area Network (hereinafter referred to as CAN), isISOStandardizedserial communication protocol. In the automotive industry, for comfort, convenience, low pollution, low cost requirements, a variety of electronicControl Systemwas developed. Because the types of data used for communication between these systems and the requirements for reliability are not the same, there are many cases of multiple buses, and the number of wiring harnesses has also increased. In order to adapt to "reduce the number of wiring harnesses", "through multiple LAN, the need for high-speed communication of large amounts of data ", 1986 German electrician.BoschCompany develops CAN for carscommunication protocol. Since then, CAN has been standardized through ISO11898 and ISO11519, and has become the standard protocol for automotive networks in Europe. Is widely used in the marketFieldbusOne.in North America andWestern Europe,CANBus protocols have becomeautomotive computer control systemand embedded industrial control LAN standard bus, and has.CANDesigned for large trucks and heavy machinery vehicles for the underlying protocolJ1939Agreement. In recent years, its high reliability and good error detection ability has been paid attention to, and it is widely used in automobilecomputer control systemand industrial environment with harsh ambient temperature, strong electromagnetic radiation and large vibration.
CAN high performance and reliability has been recognized, and is widely used in industrial automation, ships, medical equipment, industrial equipment, special vehicle control and so on.CANBusIt is one of the hotspots in the field of automation technology development today, and is known ascomputer local area network. It appearsdistributed control systemRealize eachNodereal-time, reliable data communication provides strong technical support.
The communication mode of the control system of the fracturing truck adopts CAN.The bus method meets strict vehicle-level, real-time, environmental adaptability and other severe level requirements. At the same time, it is compatible with the engine communication bus to obtain engine information and control engine speed without secondary conversion.
4, DanfossMORE 1Controller
Danfoss PLUSThe +1 controller is a vehicle-level controller that uses a CAN bus-based communication network. This flexible development system allows manufacturers to realize truly professional and intelligent electrical control systems. Thereby improving their product performance, extending the service life of equipment, and reducing the development cost of new products. 30 years of experience in the development of electrical components of walking equipment. Sauer-Danfoss company is committed to meeting the stringent standards of industrial applications. The module integrates analog input and analog output ports, each port is equipped with overcurrent and overvoltage protection, the output port drives current 3A, and the overload is automatically turned off, which can eliminate the rear-stage relay, amplifier board and other drive accessories, making the whole system more concise and reliable.
system advantage ：
TMS320F2810 DSP (32Bit Digital Signal Processor) 150MhzWorking frequency, the industry is currently a leader.
Operating voltage: 9 to 36VDC, Used in vehicles, without a separate voltage stabilizing system, can be directly connected to the battery.
Working temperature:-40°C to 70°C to meet stringent automotive grade requirements.
Protection class: IP67, dustproof, waterproof, anti-salt spray.
Program Scan Cycle Less than 1msAt present, the industry is the leader.
A/DAccuracy 12bit, you can directly collect analog.
D/AAccuracy 123A can directly drive the solenoid valve.
5Hardware design of fracturing control system
The topology structure of the whole fracturing system is shown in the figure.2, In the system, the instrument car is the control core, throughCANThe bus is connected to the sand mixing truck and fracturing truck, and the data to be shared by each truck is put intoCANon the bus; each car has its ownPLCThe system input port collects field sensor parameters and is connected to the field control panel to complete manual operation of the bicycle.PLCBoth analog and switch output ports can directly drive on-site on-off valves, proportional valves, proportional pumps, etc.; on-sitePLCHomogeneousCANbus,J1939The protocol can directly communicate with the on-site engine: read engine parameters, control engine speed, etc.
6Design of fracturing truck software
The fracturing operation software system is mainly used to monitor the relevant pressure, casing pressure, displacement, stage fluid volume, total fluid volume, density, water power, construction time and other parameters in the process of acidification, fracturing and cementing, display and print curves in real time, record, store and replay the parameters of the construction process at any time. The instrument car can control multiple fracturing truck groups, realize multi-vehicle start-stop, shift, throttle control, fault alarm. The start-up, gear shifting, throttle and overpressure protection of each fracturing train shall be controlled in all directions.
The control system is mainly composed of local control system and remote control system, The local control system is mainly used to control the local equipment. The remote control system can not only control the local equipment, but also control the equipment in the whole train group, The control system uses CANThe bus interface is convenient for data acquisition and real-time monitoring during the operation of the vehicle group. In order to ensure the effectiveness and stability of the control system, the local control system and the remote control system are designed to consider the use of 2-way CAN bus to achieve two-way redundancy. In the future, the control system can provide Chinese and English operation interfaces, metric and imperial switching functions, and operators can operate the control system according to their usage habits.
The real-time construction data and curves collected by each vehicle can be transmitted to the instrument vehicle, where the data monitoring and remote control of the working vehicle can be completed.