| Author | Bato-on, Mercedes Seco |
| Call Number | AIT Thesis no.ET-92-12 |
| Subject(s) | Thesis (M.Eng.) - Asian Institute of Technology
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| Note | A thesis submitted in partial fulfillment of the requirement for the degree of Master of Engineering |
| Publisher | Asian Institute of Technology |
| Abstract | Communicable diseases common among children throughout the developing world could be controlled through immw1ization using vaccines. Refrigeration of vaccines dW'.i (lg transportation and storage in remote rural areas is a major probl em because most of these areas h ave no grid electricity or fuel and power suppJie::; are w1re1iable. To alleviate this logistical difficulty, the use of solar photovoltaic (PV) refri gera tor under the encouragement of tlrn ExpruJded Progrrun on Jmm'W1ization (EPI) of the World H ealth Orgru1ization (WH O) is growing rapidly. However, around 50% only of t he more than 1,000 PV medical refiigerators are fow1d to fw1 ction w ccessfully. The major cause of syst em failures is due to improper sizing of the system componen ts. Existing PV system simulation models apply only t o PV systems with maximum power trackers and gen eralized loads, i. e. load is expressed in tenns of a constant or uniformly vruy ing energy demand throughout the day. This study is focused on the development of a simulation model t o predict the perfomrnnce of a small-scale stand- alone photovoltaic vaccine refrigeration system in clruJ1ped voltage mode w1der the condition of no door opening. To achieve th.is objective, experimental tests on the PV refrigeration system components were carried out to determine its perfonrnmce parru1rnters. From the result::; derived from these experiments, a system simulation model was developed. In order to validate the accuracy of the model, the whole refrigeration system was run w1der two conditions, n a.mely; days witJ1 sw1, and days with no sun. The results of the expe1imental tests were then compared to the results obtained from th e simul ation model. Results of the experiments showed that the standard deviation of the predict ed array current from the experiment al values is less th an 0.2 Amperes during low module temperatures and low to moderate insolation. At higher insolation and module temperatures, tl1e predicted values are higher and the deviatjon could reach u p t o almost 1 Ampere. The deviation of the predicted battery dischargin g cunent from the experimental values is around 0.2 Amperes, while during chru·ging deviation js arow1d 0.5 Amperes. Th e predicted hattery voltage is 2% more than the actual batte1y voltage durlng charging, but during discharge, differen ce was lesser than this percentage (about l % only). The average of the predicted vaccine load t emperatw·e is less thru1 tl1e averagl:! of the experimental values by abut 0. 15 °c. The average of the predicted wall t emperattue i::; 0.6 °c lesser thruJ experimental average. l)ue to these results (precliction of the temperatures is lower), the preclictecl energy consumption is arow1d 13% more I.him the actual energy conswnption. The results of the validation showed tha t the simulation model is fairly accurate to predict and asses the short term perfonnruJce of PV refrigeration system given th e same operating conditions. This simulation model could therefore serve as a t ool to validate other existing simplified models on PV systems. |
| Year | 1992 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Energy and Climate Change (Former title: Department of Energy, Environment, and Climate Change (DEECC)) |
| Academic Program/FoS | Energy Technology (ET) |
| Chairperson(s) | Supachart Chungpaibulpatana; |
| Examination Committee(s) | Exell, Robert H. B. ;Surapong Chirarattananon; |
| Scholarship Donor(s) | Canadian International Deyelopment Agency (CIDA); |