The Study And Application Of The Liquid Resistance Soft Start Speed Intelligent Control System

With the development of science and technology, the automatic level of the production process improves constantly, how to start the motor is becoming a focus of professionals.The resistance of the liquid resistance soft start system has good elasticity.It has many advantages,such as easy to operate,reliable pump performance,easy service,low cost sensor element,ect. It has a widely used in chemical engineering,metallurge,construction,light industry fields.By means of the liquid resistance soft start system,the dissertation designed the global structure.Aiming at character and function of the liquid resistance soft start system,it utilized the FX2N-64MR-001 PLC of MITSUBISHI as the controlling core of the liquid resistance soft start system in this dissertation.Then I devise the hardware part,it include the main circuits,control circuit,Human-computer Interface.To separated the design of each module,and finally integrated together, not only greatly reduced the hardware design cycle,but also more convenient for the debugging and maintenance.The entire software part is divided into parts,according to the different function. Sub-block model made the entire software design more clearly,the program's error rate lower,and also provided a lot of convenience to in the debugging process.In the control process of the liquid resistance soft start system, the fundamental algorithm uses the pid control combining vague control algorithms. Use their advantages for the segmented control.So then we can get the perfect feature.Finally,took Proteus as the simulation software of the V/F circuit,by changing the values of the voltage Ui,we can got the chart of voltage-frequency conversion.For the overall system simulation using Matlab software, we got the different waveforms from a direct-start system and a soft start-system,the result proved that the liquid soft-start system can meet requirements and objectives that are expect.