Abstract: One-stage power factor correction (PFC) with output electrical isolation. Two types of PFC converters are proposed here: 1) Multi stage capacitive-switching network low voltage PFC converter and 2) two-switch soft switching PFC converters. This resulted in a near unity power factor AC-DC converter with low voltage output. The second converter uses the power switch in combination with a grounded auxiliary switch to produce soft-switching converter to operate in high switching frequencies. Due to its simplified power stage and control circuit, this converter presents a variety of benefits including better efficiency (87%), lower cost, higher reliability, increased operating frequencies into the hundreds of kilo-hertz range and low operating voltages of less than 5 volts. With PSPICE simulation and experimental results, a measured power factor of 0.99 was obtained by the single switch converter.

Abstract: A compound condensing device to be used in an air conditioner having at least two condensing stages, one behind another, along the blowing direction of a common air blower to reduce the temperature and pressure of the refrigerant in the coiled pipe extending from the exiting end of the compressor and input end of the expanding device. In both condensing stages, coiled pipe sections are arranged in an up-and-down array, and evaporative cooling liquid droplets are distributed over the coiled pipe to extract heat from the refrigerant in the coiled pipe. Furthermore, fins and water-retaining material wrapping around the coiled pipe are used to increase the efficiency of evaporation. With the arrangement of two or more condensing stages, the exiting air from the compound condensing device has a temperature of about 28.5.degree. C.

Abstract: A multistage condensing structure using a liquid dispensing means to transfer droplets of evaporative cooling liquid onto an air-cooled condenser, taking advantage of the conventional air-cooled condensing method and the evaporation method using a liquid coolant. To further increase the efficiency of the air conditioner, two or more condensing units can be arranged in tandem along the blowing direction of a common air blower. With two or more condensing units arranged in tandem, the contacting area between the evaporation surfaces and the air flow can be enlarged to increase the evaporation efficiency without significantly increasing the size of the air conditioner. The multistage condensing structure, with its continuous heat-exchange along the flow of the refrigerant in the coiled pipe, causes an increase in the subcooling condition in the refrigerant. This condensing structure can, therefore, achieve a much higher E.E.R. than the known method of air cooling.

Abstract: A method and system to distribute evaporative cooling liquid onto a heat-exchanger in an air conditioner which uses a rotating air blower to generate a forced air flow toward the heat-exchanger. The liquid distributing system consists of a liquid dispenser fixedly mounted on the rotating axis of the air blower, a liquid supplier to provide the cooling liquid to the liquid dispenser. As the blades of the air blower are turned to provide a forced airflow, the liquid dispenser rotates along with the rotating axis of the air blower. The centrifugal force resulting from the rotating motion of the liquid dispenser causes the liquid received by the dispenser to scatter toward the heat exchanger.