Load-balancing functionality in a pump unit

A controller for controlling a pump with a variable pump capacity (PCC) in a pump unit for a first fluid circuit,

• wherein the first fluid circuit is provided with several pump units for cycling a first fluid in the first fluid circuit and provides external signals (EXS) including information on:
• a global pressure drop (GDP) in the first fluid circuit,
• a global average pump capacity (GAPC) of the pump units in the first fluid circuit, and/or
• individual pump capacities of the other pumps of the other pump units in the first circuit,
• wherein the pump unit has measurement means for providing internal signals (ITS) that are indicative of an individual pressure increase (IPI) of the first fluid in the pump unit caused by the pump;
• wherein the controller comprises a sensor interface for receiving the internal signals (ITS), a communication interface for receiving the external signals (EXS), and a memory;
• wherein the controller is configured to:
• obtain the individual pressure increase (IPI) based on the internal signals (ITS),
• control the pump capacity (PPC) based on the external signals (EXS) in a normal-mode operation;
• determine that the external signals (EXS) are received no longer and/or receive a failure-indication signal from the first fluid circuit, and, in response, automatically switch to a failure-mode operation;
• wherein the controller is further configured to:
• store reference information (RFI) in the memory, wherein the refence information (RFI) is based at least on a part of the external signals (EXS) received by the controller in the normal-mode operation, and control, in the failure-mode operation, the pump capacity (PCC) based at least on the individual pressure increase (IPI) and the reference information (RFI) and/or
• control, in the failure-mode operation, the pump capacity (PPC) based at least on the individual pressure increase (IPI), on the pump capacity (PCC) of the pump, and a failure-mode specific adaptation of a deadband (DB) for controlling the pump capacity (PCC).