MOTOR HOUSING TEMPERATURE CONTROL SYSTEM

摘要

A method and apparatus for controlling temperature of a compressor motor (170) having a motor cooling circuit in a refrigeration system (1014) is provided. The motor cooling circuit includes a second expansion valve (1043) providing fluid communication between the condenser and the compressor motor. The compressor motor (170) is in fluid communication with the refrigeration circuit (1014) between downstream of the first expansion valve (1040) and a compressor inlet. Refrigerant is provided as a cooling fluid to the motor cooling circuit. A primary PID loop (402) and a secondary PID loop (414) are used to control the temperature and the flow of refrigerant to the motor (170).