| The LABVIEW technology is adopted in this text, and strictly according to the standard of safety checking of mine fan system, Improve and expand the plain system unceasingly on the basic of experiment and theory-analysis, it is perfected with the function-check system of mine fan based on VI. In the research of system performance, it is very difficulty to research the system directly on the whole, because the entire system is very complicate, therefore in the process of research, The system is divided to two parts with the hardware and the software, then,from the angle of in-line system, making use of basic knowledge of control theory research and evaluate the performance of entire-system. Finally through the experiment, static-pressure testing and drawing of function-curve about fan are finished. The system is able to realize comprehensive testing of fan-performance, simplifying the job of testing, improving the safety of testing, therefore, This system has some utility value.In the process of the hardware research, it is confronted with the problem of hardware chosen first, by our reality surveying in Xi'an coal institute and being tied our reality, it is selected to the hardware part (the sensor and data-collector of testing the various parameter of testing system experiment platform is built; secondly at the basic of experiment, Static state-curve of pressure sensor is drew with the way of minimum two multiplication. and calculate its parameters on static state. Finally, Its dynamic character is researched making use of the standard signal generator and get the dynamic state-equation of pressure sensor, calculating its dynamic response parameter.With the programming language of LABVIEW, and adopting the design conception of modular,layering and the method of component oriented design, the software of fan performance inspecting-testing system was developed. The online monitoring of single performance parameter, the processing of acquired data and the management of data,, the protracting of the fan performance curve, the creating of Word-report and other functions, Besides, This paper experimented with unit-step response to static pressure testing program, obtained the response data of static pressure testing program, established the mathematic model of the system. Using the limits-theorem of the Laplace transformation, the parameters of the hypothesis model were imputed and getting the math-model of the system; the hypothesis model was tested by testing plan of the self-relation function, getting that: no matter whatαis 0.01 or 0.05,both of the result are less than theχ2m ,α,soε( k) is viewed as white-noise. This result of testing indicating, the order-estimating and the parameter-estimating of the system model are rational.According to above results, multiplying the sensor dynamic model and static pressure program model, it is the mathematic model of entire system, it is the product of proportional link and oscillating link ,and make use of control-theory to analyze its stability, response time, working band and anti-interference.The experimental verification of the VI base fan test system was accomplished in the laboratory,Running condition of the fan is changed by changing the angle of baffle plate, and record the data of fan experiment. The performance curve of fan was also obtained. By comparing the testing result of VI and the testing result of common instrument, it is got that every kind of performance index of this system can satisfy the request of fan test. |
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