METHOD FOR OPERATING A REFRIGERATION SYSTEM WITH A HEAT PUMP FUNCTION AND A REGENERATION FUNCTION FOR HEAT SOURCES, REFRIGERATION SYSTEM, AND MOTOR VEHICLE COMPRISING SUCH A REFRIGERATION SYSTEM

Abstract

A method is described for operating a refrigeration system having a heat pump function for motor vehicle, including the following steps: setting a heat pump operation, in which the refrigerant is routed from the refrigerant compressor into the secondary line; setting an expansion valve assigned to the third heat exchanger such that a total mass flow of refrigerant flows through the third heat exchanger; detecting the temperature of the coolant in the third heat exchanger. The total mass flow of refrigerant is routed through the third heat exchanger when the temperature of the coolant is greater than an upper limiting temperature.

Description

Claims

1-19. (canceled)

20. A method for operating a refrigeration system having a heat pump function for a motor vehicle, wherein the refrigeration system comprises: a refrigerant compressor, which is connectable or connected to a primary line and a secondary line;a directly or indirectly acting external heat exchanger, which is arranged in the primary line;an evaporator, which is arranged in the primary line;at least one further heat exchanger representing a heat source, in particular a heating register, which is arranged in the secondary line;a primary line valve arranged between the refrigerant compressor and the external heat exchanger;a secondary line valve arranged between the refrigerant compressor and the further heat exchanger, in particular a heating register, representing a heat source;a third heat exchanger, in particular a chiller, which operates as a water heat pump and acts directly or indirectly;wherein the method comprises the following steps: setting a heat pump operation, in which the refrigerant is routed from the refrigerant compressor into the secondary line;setting an expansion valve assigned to the third heat ex-changer, in particular a chiller, such that a total mass flow of refrigerant flows through the third heat exchanger and is evaporated in the third heat ex-changer by waste heat from coolant circulating in the third heat exchanger;detecting the temperature of the coolant in or at the third heat exchanger;wherein the total mass flow of refrigerant is routed through the third heat exchanger when the temperature of the coolant is greater than an up-per limiting temperature (Tgo).

21. The method as claimed in claim 20, wherein an expansion valve as-signed to the external heat exchanger is set in such a way that a partial mass flow flows through the external heat exchanger operating as an air heat pump, wherein at the same time the expansion valve assigned to the third heat exchanger is set in such a way that a partial mass flow of refrigerant continues to flow through the third heat exchanger.

22. The method as claimed in claim 21, wherein an expansion valve as-signed to the external heat exchanger is at least partially opened as a function of a difference between the temperature of the coolant in the third heat exchanger, in particular the chiller, and a lower limiting temperature, in particular if the difference is 2 K or less.

23. The method as claimed in claim 21, wherein the flow of a partial mass flow of refrigerant through the external heat exchanger is maintained until the coolant temperature has reached the upper limiting temperature or is greater than said temperature.

24. The method as claimed in claim 21, wherein the upper limiting temperature and the lower limiting temperature are selected as a function of a detected ambient temperature.

25. The method as claimed in claim 21, wherein the upper limiting temperature and the lower limiting temperature are selected as a function of a detected relative humidity of the environment.

26. The method as claimed in claim 21, wherein the upper limiting temperature and the lower limiting temperature are selected as a function of a temperature difference possible in operation of the refrigeration system between the ambient temperature and the refrigerant temperature in the external heat ex-changer.

27. The method as claimed in claim 26, wherein the expansion valve assigned to the external heat exchanger is set in such a way that the refrigerant temperature at the entrance to the external heat exchanger is less than or equal to the ambient temperature, in particular is 1 to 5 K less than the ambient temperature.

28. The method as claimed in claim 21, wherein the expansion valve, which is assigned to the external heat exchanger, is closed as a function of the difference between the temperature of the coolant in the third heat exchanger, especially the chiller, and the lower limiting temperature, in particular if the difference is greater than 5 K.

29. The method as claimed in claim 20, wherein at least one electrical heating element is activated, as a function a difference between the temperature of the coolant in the third heat exchanger, in particular the chiller, and a lower limiting temperature, in particular if the difference is 2 K or less, in order to supply heat to the refrigerant upstream or downstream of the third heat exchanger.

30. The method as claimed in claim 29, wherein the electric heating element is deactivated as a function of the difference between the temperature of the coolant in the third heat exchanger, in particular the chiller, and the lower limiting temperature, in particular if the difference is greater than 5 K.

31. The method as claimed in claim 20, wherein, as a function of a difference between the temperature of the coolant in the third heat exchanger, in particular the chiller, and a lower limiting temperature, in particular if the difference is 2 K or less, at least a partial mass flow of refrigerant downstream of the further heat exchanger, in particular the heating register, can be routed to the low-pressure side while bypassing the third heat exchanger and/or the external heat exchanger.

32. The method as claimed in claim 31, wherein bypassing of the third heat exchanger and/or the external heat exchanger for the rerouted mass flow of refrigerant is ended as a function of the difference between the temperature of the coolant in the third heat exchanger, in particular the chiller, and the lower limiting temperature, in particular if the difference is greater than 5 K.

33. A refrigeration system having a heat pump function for a motor vehicle, wherein the refrigeration system comprises: a refrigerant compressor, which is connectable or connected to a primary line and a secondary line;a directly or indirectly acting external heat exchanger, which is arranged in the primary line;an evaporator, which is arranged in the primary line;at least one further heat exchanger representing a heat source, in particular a heating register, which is arranged in the secondary line;a primary line valve arranged between the refrigerant compressor and the external heat exchanger;a secondary line valve arranged between the refrigerant compressor and the further heat exchanger, in particular a heating register, representing a heat source;a third heat exchanger, in particular a chiller, which operates as a water heat pump and acts directly or indirectly;wherein the refrigeration system includes at least one temperature sensor which is configured to detect the coolant temperature in the third heat exchanger, in particular the chiller, and the refrigeration system is configured to set the expansion valve assigned to the third heat ex-changer and an expansion valve assigned to the external heat ex-changer as a function of the detected coolant temperature.

34. The refrigeration system as claimed in claim 33, further comprising at least one bypass section which branches off downstream of the further heat exchanger, in particular a heating register, which discharges on the low-pressure side upstream of the refrigerant compressor, and which forms a bypass of the third heat exchanger and the external heat exchanger.

35. The refrigeration system as claimed in claim 34 wherein a bypass expansion valve is arranged in the bypass section.

36. The refrigeration system as claimed in claim 34, wherein the bypass section discharges upstream of a refrigerant collector on the low-pressure side.

37. The refrigeration system as claimed in claim 33, further comprising at least one electrical heating element which is assigned to the refrigerant circuit and is configured to heat the refrigerant as required.

38. A motor vehicle, in particular at least partially electrically operated motor vehicle, having a refrigeration system as claimed in claim 33.

39. The method as claimed in claim 22, wherein the flow of a partial mass flow of refrigerant through the external heat exchanger is maintained until the coolant temperature has reached the upper limiting temperature or is greater than said temperature.