Development of Scroll Compressor for 16HP VRF System

Usage of multiple compressors is applied for general VRF system at more than 12HP capacity because it is difficult to keep capacity and performance by usage of one compressor for such large capacity system. But usage of multiple compressors has problem controlling cost and keeping oil level in each compressor. In this paper, new scroll compressor which can reduce oil circulation in refrigerant circuit, keep oil level in the compressor, keep high capacity and performance and operate in a wide running range and can be applied until 16HP capacity by usage of one compressor was developed. It is important to keep oil level in a compressor because VRF system has large refrigerant circuit. Analysis of oil and refrigerant flow in the compressor was applied and structure of preventing oil agitation was introduced to reduce oil circulation in refrigerant circuit and keep oil level. The compressor for VRF system is demanded to operate in a wide running range from low speed to high speed and from low load to high load. This compressor can supply oil even if rotational speed is low because this compressor supplies oil by differential pressure and can supply enough oil at low differential pressure by new structure of oil lubrication, therefore running range become wider. And analysis of lubrication between shaft and bearing was applied and this compressor can keep reliability against high load at large capacity by optimal structure