가변 용량 압축기를 이용한 과급기의 성능 향상

A waste gate turbocharger cannot reach its normal power right after a vehicle starts because of its low exhaust gas pressure and intake charging ratio. On the other hand, a variable geometry turbocharger can reach higher power than waste gate turbocharger at starting time by maximizing the air induction at low speed. However. the variable geometry turbocharger by itself is not adequate to meet the engine performance due to the compressor surge. In this paper, we developed a variable geometry compressor (VGC) to enhance the engine performance by avoiding the compressor surge. We applied the moving inlet vain of the variable geometry turbine to the diffuser vain of the compressor. The developed VGC/VGT system has wider stabk region by adjusting the diffuser vain of the VGC and we can control the compressor surge by the developed VGC. Finally we build a test rig and verify the effectiveness of the developed VGC/VGT system.