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为提高中低品位地热发电系统性能，减少发电过程单位功耗?损，针对373-423K范围地热水热源，提出一种基于地热热源的分流喷射?ORC 系统以及由喷射器工作条件确定两级换热器蒸发温度的方法，并建立喷射及发电模型。在热力学及能量定律的基础上，编制计算程序分析不同升压比下，两级换热器中蒸发温度对系统性能及喷射器可逆性程度的影响；对不同热源温度下3种系统工况点参数及性能进行分析比较。结果表明：分流喷射/喷射?ORC 系统均具有一最佳升压比a，且其最佳蒸发温度高于ORC系统；随一级蒸发温度升高，系统净输出功降低，而随二级蒸发温度增加，系统热效率增长；在不同热源温度下，分流喷射?ORC系统均具有最高性能，且随热源温度增加，其性能优越性逐渐增强，在Tg=373、423K时，分流喷射?ORC系统可达到净输出功P=280.88、954.82kW，分别高出喷射?ORC及ORC系统12.54、76.31及55.68、141.52kW。通过分流喷射能够提高地热ORC发电性能，热源温度越高，选择分流喷射系统意义愈明显。“,”In order to improve the performance of low grade geothermal power generation system, and reduce the exergy loss of per unit work, the geothermal bypass injection-ORC system and the method to determine the evaporator temperature range by the injector working conditions were proposed for 373-423K geothermal water heat sources, and the injection and power generation model were established. The influence of two grade heat exchanger evaporator temperature on the performance and injector reversible degree under different boost ratios was analyzed based on the thermodynamic rules and energy principle by wrote the calculation program. The comparison of operating parameter and performance with heat source temperature on three kinds systems were finished. The results show that both two systems with or without bypass have an optimum boost ratio, and which optimal evaporator temperatures are higher than ORC system. The output work decreases with the high grade evaporator temperature, and the thermal efficiency increases with low grade evaporator temperature. The bypass injection-ORC system has the best performance under any heat source temperature, and with the increase of heat source temperature, the superiority is enhanced gradually. The new system can reach 280.88kW, 954.82kW when the heat source temperature is 373 and 423K. It increased by 12.54kW, 76.31kW and 55.68kW, 141.52kW relative to injection-ORC and ORC system respectively. The performance can improve by bypass injection and the higher the heat source temperature is, the significance of choosing the new system is more obvious.