公开(公告)号：US20180320944A1

公开(公告)日：2018-11-08

申请号：US15763988

申请日：2016-10-14

Applicant: DANFOSS A/S

Inventor： Jan PRINS ,  Frede SCHMIDT ,  Kenneth Bank MADSEN ,  Kristian FREDSLUND

IPC: F25B49/02 ,  F25B9/08 ,  F25B6/02 ,  F25B5/02

CPC classification number: F25B49/022 ,  F25B5/02 ,  F25B6/02 ,  F25B9/08 ,  F25B2341/0012 ,  F25B2400/075 ,  F25B2400/16 ,  F25B2400/23 ,  F25B2500/28

Abstract: A method for controlling a vapour compression system (1) is disclosed. The vapour compression system (1) comprises an ejector (6) and a liquid separating device (10) arranged in a suction line. At least one evaporator (9) is allowed to be operated in a flooded state. A flow rate of refrigerant from the liquid separating device (10) to the secondary inlet (15) of the ejector (6) is detected, and it is determined whether or not the flow rate is sufficient to remove liquid refrigerant produced by the evaporator(s) (9) being allowed to be operated in a flooded state from the liquid separating device (10). In the case that it is determined that the flow rate of refrigerant from the liquid separating device (10) to the secondary inlet (15) of the ejector (6) is insufficient to remove liquid refrigerant produced by the evaporator(s) (9), the flow rate of refrigerant from the liquid separating device (10) to the secondary inlet (15) of the ejector (6) is increased, and/or a flow rate of liquid refrigerant from the evaporator(s) (9) to the liquid separating device (10) is decreased.

公开(公告)号：US20240191921A1

公开(公告)日：2024-06-13

申请号：US18550799

申请日：2022-02-18

Applicant: Danfoss A/S

Inventor： Peter REICHWALD ,  Jan PRINS ,  Salvatore PISCOPIELLO

IPC: F25B41/39

CPC classification number: F25B41/39 ,  F25B2400/0409 ,  F25B2400/23 ,  F25B2500/19 ,  F25B2600/02 ,  F25B2600/2501

Abstract: A vapour compression system (1) including a compressor unit (2) having at least one main compressor (3) and at least one receiver compressor (4), a heat rejecting heat exchanger (5), a receiver (7), an expansion device (8) and an evaporator (9) being arranged in a refrigerant path. The vapour compression system (1) further includes a bypass valve (12) fluidly interconnecting the gaseous outlet (10) of the receiver (7) and the main compressor(s) (3). A pressure difference across the bypass valve (12) is measured or derived, and a mass flow rate of refrigerant through the bypass valve (12) is derived, based at least on the pressure difference across the bypass valve (12), and using a fluid model. A minimum mass flow rate of refrigerant required to operate the receiver compressor (4) is derived, based on a minimum displacement volume of the receiver compressor (4) and using a fluid model taking prevailing operating conditions into account. In the case that the derived mass flow rate of refrigerant through the bypass valve (12) exceeds the derived minimum mass flow rate of refrigerant required to operate the receiver compressor (4), the receiver compressor (4) is started and the bypass valve (12) is closed.

公开(公告)号：US20240142150A1

公开(公告)日：2024-05-02

申请号：US18550814

申请日：2022-02-18

Applicant: Danfoss A/S

Inventor： Jan PRINS ,  Peter REICHWALD ,  Salvatore PISCOPIELLO

IPC: F25B49/02 ,  F25B41/20

CPC classification number: F25B49/02 ,  F25B41/20 ,  F25B2400/0409 ,  F25B2600/2501

Abstract: The vapour compression system (1) includes a compressor unit (2) having at least one main compressor (3) and at least one receiver compressor (4), a heat rejecting heat exchanger (5), a receiver (7), an expansion device (8) and an evaporator (9) being arranged in a refrigerant path. The vapour compression system (1) further includes a bypass valve (12) fluidly interconnecting the gaseous outlet (10) of the receiver (7) and the main compressor(s) (3). A first pressure setpoint for a pressure prevailing in the receiver (7) and a second pressure setpoint for the pressure prevailing in the receiver (7) are defined, the second pressure setpoint being higher than the first pressure setpoint. An opening degree of the bypass valve (12) is controlled in order to regulate the pressure prevailing in the receiver (7) in accordance with the first pressure setpoint, and in order to reach the first pressure setpoint, in the case that a load demand of the vapour compression system (1) exceeds a maximum capacity of the receiver compressor(s) (4). The opening degree of the bypass valve (12) is controlled in order to regulate the pressure prevailing in the receiver (7) in accordance with the second pressure setpoint, and in order to reach the second pressure setpoint, in the case that the receiver compressor(s) (4) is/are operating and the load demand of the vapour compression system (1) is below the maximum capacity of the receiver compressor(s) (4).