System uses Automatic Frequency Control regulation or pump motor speed.doc

外文原文 Wincc in Heating Supply Stations Monitoring SystemSystem uses Automatic Frequency Control regulation or pump motor speed. Plus or minus pump.It isprimarily by the Frequency Control System.PID regulator,pressure sensors,liquid level sensor power control circuits and other conponents.Host users control system or control board light over-the-counter transactions,buttons,switchto understand and control systen operation,Based on the PID control mode,the operator interface settings in water pressure,PLC to pressure settings and measured valucs for the deviation PID operation and regulation of distribution through inverter pump speed,so that water pressure was maintained at the set value.1 、Systen hanlware configurationThe system uses Siernens S7-200 PLC and its configuration software constitute a constant WinCC V6.0 Water pressure control system , water pressure monitoring process.Industroal Ethernct controller for PLC and the operator station computer communication betwween the Remote I/O network for the PLC and the operator station compuler communication betwween the Remote I/O network for the PLC controller and inverter,the soft starter of communication betwween equipment.PLC controller mainly used to monitor and control water and electricity systems.For1#-4#pressurized pump converter using the ABB Acs510-01-031A4 inverter,HMI operatostation selection DELL conputers,conputer,Industrial Ethernet server card Siemens conmmunications company CP1612.2.Software design of SystenThe control system software company Siemens PCS7V5.2 package,STEP7V5.2 PLC controller mainly used to monitor and control water and electricity systems.For 1#4# pressurized pump converter using the ABB ACS510-031A4 inveter,HMI operatorstation selection DELL puter,Industrial Ethernet server card Siemens communications company Cp1612.3.Software design of SystemThe control system software company Siemens PCS7V5.2 package.STEPV5.2 PLC controller.HMImonitoring system used WinCCV6.0 version.HMI server and operating station are using the Windows2000 operating system to have an open programming environment.Heating Sation Wincc configuration control software maior constant pressure water system and coal Gallery in two parts.Implemention of the system of automatic detection and automatic control.Detection constant pressure water and coal Gallcry equipment operation parameters.the real-time data acquisition.uploads.real-time data acquisition.uploads,real-time display and recording.Ciontrol unit operation.fault alarm and automatic parking operation .Theconstant pressureof water supply pressure system configuration parameters.real-time monitoring regulatory pressure pumps water pressure and so valued.CoalHanding Gallery in to control the volume.of coal to speed,to monitor the quality of coal (coal crushing degree of quality and impurity).PLC-Based Fuzzy Constant water Supply System Design Constant1.pressure water system componentsFrom the water supply system programmable controller, inverter,pressure transmitter and the constact group on the pump unit and other components Programmable controller selection of AB ControlLogix system.It includes Logix5550 controller analog input modules,digital input and output modules and communication modutes.Which analog input modute used to test the water pressure on the export signal,digital input module and valves Kai stopped.Inverselection of AB 1336 Plus Inverter.Inverter and Devi2 cenet controller thtough the network for communication.2.Constant Pressure Water PrincipleThe outlet channel of pressure sensor installation will export water pressure signals are converted to electrical signals, send PLC fuzzy inference operation, the output control signals to the converter, regulating the operation of pump motor speed, until the actual elimination of hydraulic pressure and set the deviation, constant voltage supply. Programmable controller can control pumps Kai stopped. When the system started working, inverter control from start on 1st pump frequency operation. If users increased consumption of the converter output frequency up to 50 Hz, the pressure will still be less than the set value, then after some time delay, on the 1st of the pump switching frequency operation; Inverter start again on the 2nd pump operation. If pressure is less than the set value, they will be on the 2nd to pump switching frequency operation; Inverter start again on the 3rd pump operation until the output pressure settings to achieve so far. However, if users to reduce water consumption, in accordance with the “Kai-stop” principle will be followed with pumps. This cycle repeatedly to achieve constant pressure water system.3.Fuzzy2PI control algorithm As the water supply system in many areas (such as the pipe network and pumps) nonlinear, time-varying, and the variables still exist between the cross-coupling, so it is difficult to establish a precise mathematical system model. For such a complicated process that merely using the conventional PID control is difficult to achieve the desired control. Fuzzy control is not dependent on the mathematical model and the right parameters sensitive to the merits, Fuzzy used to control the water supply system, we can improve the control system dynamic performance. But Fuzzy Control System steady-state performance is poor, this design of a dual-mode Fuzzy2PI control, As shown in figure 2, and its design thinking is; when the pressure is greater error when using fuzzy control, to obtain good transient; When the pressure on the stead-state error into smaller, switched to process from PI control, to obtain good steady precision. PI control algorithms and fuzzy control algorithms are PLC, switching time by a computer program based on prior to the error autormatically.The system uses two-input single-output fuzzy controller. topressure the desired value and the measurement of e error and the error as a fuzzy controller input linguistic variables, transducer frequency variation u language as output variables. To e error, the error rate ec and control volume u fuzzy subset of ( NB,NS,ZE,PS,PB) and they quantified the domain of seven grades, (-3,-2,-1,0,1,2,3). Fuzzy subset of the membership function used triangle. Initial experience of fuzzy control rules, as shown in table 1. Under these rules calculation of the total fuzzy relation R:Where x, U fuzzy relationship matrix on behalf of the Cartesian and the and operator. According minimax inference rules synthesis of output variables language domain of fuzzy sets U:U Finally, the weighted average method used for solutions vague and fuzzy volume U converted into precise amount u. The process is carried out offline, eventually Fuzzy Control Table, as shown in table 2. This form of the PLC memory storage, real-time control, fuzzy control would streamline the process for finding inquiries on the questionnaire process.Parametric Selection of Frequency-water systemA reasonable selection pressure control parameters constant pressure to achieve energy-supply system. The realization of is this objective the key is pressure control parameter selection, usually pipe network pressure control point two choice: a pipe network is the most negative pressure on constant pressure control and the other is the constant pressure pump outletpressure control. How will the two choices, we have to analyze simple Network pressure on the most disadvantaged constant, the water pipe network by QMAX reduced to Q1, pumps reduce speed, and water characteristic curve of A (unchanged) at the intersection point C, pump characteristic curve downward, network pressure on the most disadvantaged H0. And the pump outlet pressure constant pressure control, Ha unchanged, reduce water consumption by QMAX QI and Ha to pay to point B, water characteristic curve upward A through B, the network most disadvantaged Hb pressure into points. Hb-H0 lift the poor namely, energy waste, so I chose the most disadvantaged network points for the smallest head pressure control parameters. Formation pressure on the closed-loop control system, making the pump speed and PID regulator set pressure match, achieve maximum energy-saving effect, but the constant pressure to achieve the purpose of water supply.The converter and put into operation after the commissioning of the system to ensure optimum operation of the state mea