Control System Design Of Solar Air Conditioning

Energy is the foundation of human survival. We are facing serious threat of theconventional fuels such as oil and coal. At the same time, building energy consumptionaccounted for over25%of the total energy consumption in our country, and in buildingenergy consumption, air conditioning energy consumption accounts for more than50%.There is an upward trend in the demand of building air conditioning and bring greatpressure for energy, power and environment. All over the world are stepping up thestudy of new energy and efficient air conditioning technology. Solar energy technologyand absorption refrigeration technology has been used alone for nearly half of century,but as the material, technology, design, especially the application of technologies suchas automatic control technology of continuous improvement and integration, by usingdifferent grade temperature of hot water from solar, driven absorption machineoperation to provide cooling, which improve the running efficiency of the wholesystem and return on investment, also reduce the emissions of greenhouse gases.This thesis used the parabolic focusing solar collectors, hot water designtemperature can reach180℃, and belongs to high grade heat source, can be used indouble effect absorption chillers, chiller co-efficiency of performance reached morethan1.3. In order to improve the utilization efficiency of solar energy air conditioningsystem, must solve the solar energy collector control system of tracking precision,collection efficiency, radiation intensity change, as well as the use of its hightemperature hot water and safety protection.This thesis described and analyzed the working principle detail of solar collectorand lithium bromide absorption chiller. Proposed the double heat source absorptionchiller, which design and control scheme with solar water heating as priority heatsource, gas burner as auxiliary heat source for absorption chiller, in the evening orsolar energy is insufficient, double heat absorption chiller ensure system can run stablyfor a24-hour continuous. According to the tracking operation characteristics analysisof parabolic focusing solar collector, used the control method that obit trackingmovement combined with photoelectric detection tracking, the issue of solar focusedinaccurate cause the solar energy efficiency decline has been solved, the panels canquickly find the sun focus position accurately and real-time correction, ensure that thetracking precision. Through the design and implementation of the solar energy air conditioning system, this thesis expound the control system hardware and softwarecomposition and characteristics, the control system operation interface, the importantparameters of tracking control and safety protection controlThis control system has been applied to Broad group of solar refrigerationproducts successfully, system meets the design requirements, and the products havebeen sold to domestic and overseas markets.