Ship Reefer Inverter Technology

Along with the rapid increase in the amount of perishable goods imported and exported in the world, refrigerated container transportation has been drastically developed. At present, the number of the refrigerated container has been 750 000TEU and 65 00 TEU new refrigerated container are putting into use every year. Refrigerated container transportation has played a significant role in international trade. There has 90% of the mechanical mode in the refrigerated container, energy consumption, however, has also become an unneglectable problem. This thesis is aimed to expound how to improve the work efficiency and economic benefits of refrigerating installation in refrigerated container. Aiming at energy-saving in the refrigerating system of refrigerated container: This thesis puts forward the idea of using frequency converter to achieve stepless change in compressor and air blower to make a good- matching between refrigerating capacity and refrigeration duty. In this way the goal of energy-saving can be accomplished. In the course of calculating refrigeration duty of refrigerated container, thermal analysis is made toward the course of heat transmission in the container's thermal baffle. The conclusion is that the calculation of container's refrigeration duty can apply the same way as heat response factors, which has been maturely used in air-conditioning system. Through this way the calculation of refrigeration duty can be more precise. The paper summarizes the research achievements in energy-saving technology about refrigerating machinery and air-conditioning plant. It raises the measure of energy-saving, in regard of the special transportation condition of refrigerated container. Stepless change of compressor for capacity control: Adopt the way of heat response factors to calculate variable frequency energy-saving of compressor in the container's refrigerating system ; lnleakage-heat calculating caused by the temperature difference through the refrigerated container's thermal baffle based on typical line in a specific transportation on a typical sailing date and time of a practical ship; then calculate refrigeration duty at typical time after consulting some empirical formulas recommended by relevant literatures; compare the calculated refrigeration duty with the refrigeration duty of refrigerating system under designed operating mode to get difference and fluctuating rate to illustrate the necessity of stepless change in compressor. With the calculation of variable frequency energy-saving , the 33% energy-saving rate expound and prove the feasibility of the application of the variable speed compressor in refrigerated container. Variable frequency air blower for the system air volume regulation of air-conditioning system: In the calculation of air blower's variable speed energy-saving in refrigerated container, get refrigeration duty inside the refrigerated container at typical time by the way of heat response factors. From these, the sensible heat and air volume in need at typical time can be determined; the difference between the air volume practically needed and the specified amount manifests the necessity of the application of variable speed air blower. Through the calculation of variable frequency energy- saving of air blower in a certain route, a rate of 58.8% in the energy-saving by evaporator air blower and a rate of 70% in the energy-saving by condenser air blower can be gotten. Thus, the feasibility of variable frequency in air blower is proved.