Controlling Refrigeration Compression Systems

摘要

A refrigerant compression system and method for controlling a refrigerant compression system are described. In some aspects, the refrigerant compression system includes a compressor system having a plurality of compression stages, a plurality of quench valves, a first suction temperature control circuit associated with a first quench valve, a second suction temperature control circuit associated a second quench valve, and a discharge temperature control circuit associated with a plurality of the quench valves. Quench valve settings are determined based on evaluation of one or more outputs from the suction temperature control circuits and the discharge temperature control circuit.

主权项

1. A refrigerant compression system comprising:
a compressor system having a plurality of compression stages; a first quench valve operable to provide an adjustable flow of quench fluid into a first compression stage; a second quench valve operable to provide an adjustable flow of quench fluid into a second compression stage; a first suction temperature control circuit associated with the first quench valve, the first suction temperature control circuit operable to: identify a first temperature setpoint and an inlet temperature of the first compression stage; and determine a first quench flow demand of a quench fluid flow that is injected through the first quench valve into the first compression stage based on the first temperature setpoint and the inlet temperature of the first compression stage; a second suction temperature control circuit associated with the second quench valve, the second suction temperature control circuit operable to: identify a second temperature setpoint and an inlet temperature of the second compression stage; and determine a second quench flow demand of a quench fluid flow that is injected through the second quench valve into the second compression stage based on the second temperature setpoint and the inlet temperature of the second compression stage; a discharge temperature control circuit operable to: receive information regarding a discharge temperature at an outlet of the plurality of compression stages and a discharge temperature setpoint; and determine a third quench flow demand of the quench fluid flow that is injected through the first quench valve into the first compression stage and a fourth quench flow demand of the quench fluid flow that is injected through the second quench valve into the second compression stage such that the discharge temperature at the outlet of the plurality of compression stages is maintained at or below the discharge temperature setpoint; and a first quench valve controller associated with the first quench valve, the first quench valve controller operable to: receive the first quench flow demand determined by the first suction temperature control circuit; receive the third quench flow demand determined by the discharge temperature control circuit; and determine a valve position demand of the first quench valve based on the first quench flow demand and the third quench flow demand; and a second quench valve controller associated with the second quench valve, the second quench valve controller operable to: receive the second quench flow demand determined by the second suction temperature control circuit; receive the fourth quench flow demand determined by the discharge temperature control circuit; and determine a valve position demand of the second quench valve based on the second quench flow demand and the fourth quench flow demand.