涡旋式压缩机并联运行的应用方法简析

Brief Analysis of the Application Method for Parallel Operation of Scroll Compressors

单台涡旋式压缩机制冷量小,但其单位制冷量制造成本比活塞式压缩机和螺杆式压缩机低。多台涡旋式压缩机并联运行时,并联的压缩机可逐台启动,因而可降低并联涡旋式压缩机组的启动电流;当机组运行在部分负荷时,与单台大冷量压缩机组相比:并联涡旋式压缩机组可根据系统需求负荷来控制并联涡旋式压缩机的运行数量,其与系统负荷匹配性好,可使并联涡旋式压缩机组以比较经济的方式运行;单台大冷量压缩机在部分负荷运行时需要卸载,卸载运行时其电机运行效率会降低,最终使机组运行能效变差;并联涡旋式压缩机组在部分负荷运行时,压缩机的电机不需要卸载,电机运行效率高,因而更节能;当并联涡旋式压缩机组其中一台压缩机发生故障或损毁时,并联机组中的其它压缩机还可持续工作;而单台大冷量压缩机故障或损毁时,机组将停止制冷。并联涡旋式压缩机组虽然有上述优点,但其要达到稳定运行的目的,还需解决好油平衡及容量控制等相关事宜。

The cooling capacity of a single scroll compressor is small,but its manufacturing cost of per unit cooling capacity is lower than that of a piston compressor and a screw compressor.When multiple scroll compressors are running in parallel,the parallel compressors can be started one by one,so the starting current of the parallel scroll compressor unit can be reduced.When the unit is running at partial load,compared with a single cold large-capacity compressor unit,the parallel scroll compressor unit can control the operation number of parallel scroll compressors according to the system demand load,which has a good match with the system load and can be make the parallel scroll compressor unit operate in a more economical way.A single large-capacity compressor needs to be unloaded during partial load operation.During unloaded operation,the operating efficiency of its motor will be reduced,which will eventually lead to poorer operating energy efficiency of the unit.When the parallel scroll compressor unit operates at partial load,the compressor motor does not need to be unloaded,so the motor has high operating efficiency,and it is more energy-saving.When one of the compressors in the parallel scroll compressor unit fails or be damaged,the other compressors in the parallel unit can continue to work,but when a single large-capacity compressor fails or be damaged,the unit will stop cooling.Although the parallel scroll compressor unit has the above advantages,in order to achieve the purpose of stable operation,it is necessary to solve the relevant issues such as oil balance and capacity control.