Abstract: The invention relates to a method for operating a compressor unit, in particular for underwater operation. The aim of the invention is to minimize the risk of gas hydrate formation during the compression process. To reduce said risk, according to the method components of the compressor unit are supplied with anti-freeze and/or anti-freeze is injected into the flow path of the conveyed medium to be compressed. The invention also discloses a compressor unit, which operates according to said method.

Abstract: A compressor unit for underwater operation is provided. The compressor unit includes a compressor having a compressor rotor and a plurality of compressor stages. The compressor unit also includes an electric motor having a stator, a motor rotor, and a gastight housing which is provided with an inlet and an outlet. The motor rotor has two radial bearings, namely a first radial bearing and a second radial bearing, each arranged at the ends of the motor rotor. The compressor rotor has two radial bearings, namely a third radial bearing and a fourth radial bearing, each arranged at the ends of the compressor rotor. A coupling which transmits torque is arranged between the two rotors. The above arrangement provides a remedy for vibrations for especially large compressor units.

Abstract: The invention relates to a drive system comprising a liquid-cooling electric machine (1), and to a method for liquid-cooling the stator winding of said type of machine (1). In order to use said system at very low temperatures and in the most simple way possible, said drive system also comprises a cooling circuit (2) for cooling the liquid of a stator winding of the electric machine (1), a pump (3) for pumping a liquid through the coolant circuit (2), a converter (4) for feeding the stator winding and a control device (5) for controlling the converter in such a manner that said converter, prior to activating the pump (3), feeds a heating flow to the stator winding for heating the cool liquid.

Abstract: The invention relates to a method for operating a compressor unit, in particular for underwater operation. The aim of the invention is to minimize the risk of gas hydrate formation during the compression process. To reduce said risk, according to the method components of the compressor unit are supplied with anti-freeze and/or anti-freeze is injected into the flow path of the conveyed medium to be compressed. The invention also discloses a compressor unit, which operates according to said method.

Abstract: The invention relates to a compressor unit, in particular for underwater operations, comprising a compressor with a rotational axis and an electric motor. Said compressor unit has a housing with an automation unit for control and regulation tasks. The aim of the invention is to improve the co-operation of the automation unit and the compressor unit and in particular to reduce the complexity of the cooling of the automation unit and signal and energy transmission. To achieve this, an additional housing, which contains the automation unit, is attached to the housing.

Abstract: The invention relates to a compressor unit, in particular for underwater operation, comprising a compressor with a compressor rotor which has one or more compressor stages, and also comprising an electric motor with a stator and a motor rotor, and comprising a gastight housing which is provided with an inlet and an outlet. Such compressor units in a large embodiment are especially susceptible to vibrations. The invention provides a remedy hereby virtue of the fact that the motor rotor has two radial bearings, a first radial bearing and a second radial bearing, each arranged at the end, that the compressor rotor has two radial bearings, a third radial bearing and a fourth radial bearing, each arranged at the end, and that a coupling which transmits torque is arranged between the two rotors.