Research on Testing Technology of Oil Free Compressor Air Valve of Rail Transit Air Source Device Based on PV Diagram

PV diagram can reflect the real-time thermodynamic state of reciprocating compressor and show its ability to do work, which is an effective means to study the in-service performance of reciprocating compressor. The real-time PV diagram of reciprocating compressor is obtained by testing the dynamic pressure signal and the keyphasor signal in the cylinder of oil-free compressor for rail transit air source device and converting them. Through orthogonal experimental research on the compressor valve, the compressor PV diagram under different valve states is obtained. The results show that the parameters of the compressor, such as the thickness of the suction valve slice, the thickness of the exhaust valve, the flow area of the suction valve and the flow area of the exhaust valve, have a certain impact on the performance of the air valve and the functional force of the compressor.