Study On The Fuzzy Control System Of Thermoelectric Air-conditioning Based On LabVIEW

The thermoelectric air-conditioning is also called semiconductor air-conditioning, working under Peltier effect to implement functions of refrigeration and heating. It has overcome defects on traditional air-condition, such as noise, environment pollution etc. Besides this, it has been widely used in industry, medical treatment, electron and the technology of refrigeration with its great excellence as follow: lesser noise, small in size, quick refrigeration, stable operation etc.This paper, takes the temperature control system of thermoelectric air-conditioning as subject investigated, according to the characteristics of the temperature control system such as nonlinear, large hysteresis and difficult to build a precise mathematical model, adopts fuzzy control and virtual instrument technology to develop thermoelectric air-conditioning fuzzy temperature control system basing on LabVIEW is researched and designedThe main contents are as follows:First, the basic principles of thermoelectric refrigeration are expounded; the thermodynamic properties and limiting work conditions of the thermoelectric refrigeration are analyzed and calculated.Second, according to the temperature control requirements of thermoelectric air-conditioning applicable, the fuzzy control rules applied to the system are established, completing the design of the fuzzy controller and the test of input and output performance in LabVIEW environment.Third, achieving the software design of the temperature monitoring subsystem of thermoelectric air-conditioned in LabVIEW environment on the basis of technology of signal sampling and regulation ,combined with signal regulation equipmentFourth, completing the design of regulator circuit of the PWM DC on power supply subsystem of thermoelectric air-conditioning and program design of the hardware circuit control in LabVIEW; the analyse of hardware has been taken on the PWM DC chopper circuits using PSpice, it verifies that PWM fuzzy control signal is linear proportional relationships to the output voltage.Fifth, the system's overall program designs has been completed in LabVIEW and the experiment platform of thermoelectric air-conditioning temperature fuzzy control system based on LabVIEW has been constructedPractical running indicates that this control system can work steadily, reliably and has the ability of anti-interference, verifying the good of the feasibility and adaptability of fuzzy control technology applied to the system.