Design Of Three Phase Variable Frequency Miniature Compressor And Portable Refrigerator

It is discussed in this paper that the possibility of vapor compression refrigeration technology applied in the area of portable refrigeration, and a refrigeration scheme is presented which is based on a three phase variable frequency and adjustable speed miniature compressor.According to the thermodynamics theory of vapor compression refrigeration cycle, HFC-R134a is chosen as refrigerant fluid and the thermodynamics calculation of refrigeration system is accomplished, which is based on the table of R134a thermodynamics characteristics and estimate of portable refrigerator's calorific burthen. The limitation of Mini-volume and mini-power application condition is adequately considered, and design of whole refrigeration system is accomplished farther, including choose and structure design of compressor, choose and calculation of heat exchanger, calculation of capillary, etc. Structure design of the rotary compressor is the most primary part of the design of whole refrigeration system. In order to reduce compressor's volume, a three-phase induction motor is utilized as the actuator of the compressor. SPWM variable frequency and adjustable speed technology, which develops very fast in recent years, is also used to solve the problem of electrical matching, furthermore, it can improve the condition of motor and reduce the consume of energy. The control system of variable frequency electrical power consists of a single chip computer and a special chip, which fulfill the control function, simplify the current structure and reduce the production cost.By exploitation to the potential of reduction of compressor's volume and weight, an original scheme of portable refrigeration with miniaturecompressor driven by variable frequency and adjustable speed actuator is described in this paper, and it has excellent practicality and market prospect.