Method for selecting a frequency converter for a refrigerant compressor unit

A data processing unit for selecting a frequency converter for a refrigerant compressor unit, including a refrigerant compressor and an electric drive motor,

• the data processing unit has a display unit on which a working state suitable for operation of the refrigerant compressor unit is selected within an application field of an application graph of the refrigerant compressor, an operating frequency for this selected working state is selected, and the data processing unit determines from drive data stored in a memory a working state operating current value that corresponds to the selected working state and the selected operating frequency, for operation of the refrigerant compressor unit.

A refrigerant compressor system, including a refrigerant compressor unit having a refrigerant compressor and an electric drive motor, and including a frequency converter for operating the electric drive motor, the frequency converter includes a frequency limiting unit that, at operating frequencies above a cut-off frequency, limits the operating frequency such that the maximum converter current value of the frequency converter is not exceeded.

A refrigerant compressor system, including a refrigerant compressor unit having a refrigerant compressor and an electric drive motor, and including a frequency converter for operating the electric drive motor, the frequency converter includes a voltage adapter unit that controls an increase in the output voltage over the operating frequency such that this increase is performed independently of a fluctuation in a mains voltage.