从研究涡旋压缩机工作腔和背压腔的泄漏、热和能量转换入手，建立了一个自调背压腔压力平衡系统的热力学模型．此模型不仅能预测轴向平衡系统涡旋压缩机的工作过程，而且能为背压孔的优化设计提供计算依据． Starting from the research on the leakage, heat and energy conversion in the working chamber and the back pressure chamber of the scroll compressor, a thermodynamic model of the pressure balance system of the back pressure chamber was established. The model can not only predict the working process of the scroll compressor with axial balance system, but also provide the basis for the optimization design of the back pressure hole.