Abstract: The system (100) is used for starting and synchronizing synchronous motors (10) with power electricity of an electric grid (20). The system (100) includes a variable frequency driver (30) for starting the synchronous motors (10), and an electrical diverter (61, 63) for each synchronous motor (10). The electrical diverter (61, 63) has a control input electrically coupled to a control output of the variable frequency driver (30) so to selectively couple stator windings (12) of synchronous motors (10) with a power output (33) of the variable frequency driver (30) or with the electric grid (20) based on signals that are received at a control input of the variable frequency driver (30) and represent a position of the shafts of the synchronous motors (10). Therefore, switching occurs at desired shafts positions.

Abstract: It is disclosed a method for reducing the pulsation level in a multi-compressor plant where each compressor of a plurality of compressors is driven by a respective motor. The method manages to reduce the pulsation level by starting a first motor of a first compressor and then starting in succession each one of the other motors in a way to synchronize all motors between each other with a specified phase shift.

Abstract: It is disclosed a method for reducing the pulsation level in a multi-compressor plant where each compressor of a plurality of compressors is driven by a respective motor. The method manages to reduce the pulsation level by starting a first motor of a first compressor and then starting in succession each one of the other motors in a way to synchronize all motors between each other with a specified phase shift.