US 11,906,219 B2
Flash tank-based control of refrigerant injection into a compressor
Eric Winandy, Esneux (BE); Remi Dickes, Aachen (DE); Paolo Chiaramonte, Belluno (IT); and Luca Mazzorana, Belluno (IT)
Assigned to Copeland Europe GmbH, Berlin (DE)
Filed by Emerson Climate Technologies GmbH, Berlin (DE)
Filed on Apr. 22, 2021, as Appl. No. 17/238,126.
Claims priority of application No. 20171276 (EP), filed on Apr. 24, 2020.
Prior Publication US 2021/0348813 A1, Nov. 11, 2021
Int. Cl. F25B 43/00 (2006.01); F25B 13/00 (2006.01)
CPC F25B 43/006 (2013.01) [F25B 13/00 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A method of controlling injection into a compressor in a refrigeration cycle, wherein the method is performed in a refrigeration cycle, which comprises at least a flash tank configured for receiving a refrigerant and separating liquid refrigerant and vapour refrigerant, and a compressor configured for compressing the refrigerant, wherein the compressor comprises a means for compressing, a suction port and an injection port, which is connected to the means for compressing for at least a time instance of the refrigeration cycle, wherein the flash tank is connected to the injection port of the compressor via an injection valve,
the method comprising:
determining, via a sensor, a pressure in the flash tank;
controlling, via a controller, the injection valve based on the determined pressure in the flash tank; and
controlling, via the controller, the compressor based on the determined pressure in the flash tank, wherein controlling the compressor comprises if the determined flash tank pressure is lower than a threshold, determining, by the controller, an operating speed for the compressor and setting the operating speed to the determined operating speed,
wherein the threshold is referred to as a first threshold and wherein controlling the compressor comprises:
if the controller determines that the flash tank pressure is equal to or greater than the first threshold and lower than a second threshold, unloading the compressor; and
if the controller determines that the flash tank pressure is greater than the second threshold, stopping operation of the compressor via the controller.