Abstract: A field of electric drive devices, drivetrain systems and electric machines, such as electric motors and electric generators for industrial applications, and more particularly to a method, an arrangement, and a frequency converter for identification of torsional natural frequencies of a drivetrain system.

Abstract: A medium voltage variable speed assembly including an electric machine, and a power supply configuration for supplying alternating current power to the electric machine. The electric machine includes a plurality of stator winding systems. The power supply configuration includes a supply converter system having a two-level direct current input and an alternating current output connected to the plurality of stator winding systems. The supply converter system includes a plurality of converter arrangements connected in series such that each of the converter arrangements includes at least one two-level converter unit having a DC link whose nominal voltage is low enough for IGBTs, MOSFETs or similar components. Characteristics of the electric machine such as a number of machine phases, a number of stator poles, a number of stator winding systems and a number of stator slots are selected in a specific way.

Abstract: A system for an electrochemical process comprises an electrochemical reactor (101), an electric power source (104) for supplying controllable direct voltage to electrodes of the electrochemical reactor, a measurement apparatus (105) for producing measurement data indicative of formation of product gases of the system, and a controller (106) configured to reduce the direct voltage when: an idle command to set the system into an idle state has been received, the measurement data indicates formation of the product gas, and the direct voltage is above a lower limit of a safe voltage area free from degradation of the electrodes. Thus, in the idle state, the direct voltage is reduced only by an amount needed for stopping the product gas formation but not more. Therefore, the degradation such as corrosion of the electrodes can be avoided or at least reduced in the idle state.

Abstract: An arrangement for monitoring an antifriction bearing of a rotating shaft of a rotating electric machine. The arrangement includes: one or more capacitor electrodes to measure a capacitive shaft displacement parameter; one or more of the following additional measurement sensors; a microphone to measure a bearing noise parameter, a voltage sensor to measure a bearing current parameter, and/or an optical pyrometer to measure a shaft heat parameter; and one or more processors configured to evaluate a condition of the antifriction bearing based on the capacitive shaft displacement parameter and one or more of the following: the bearing noise parameter, the bearing current parameter, and/or the shaft heat parameter.

Abstract: A field of electric drive devices and electric machines, such as electric motors and electric generators for industrial applications, and more particularly to a method, an arrangement and a frequency converter for controlling lateral vibration of an electric machine. The arrangement of the present invention for controlling lateral vibration of an electric machine includes a frequency converter, one or more vibration sensors and an electric machine, wherein the one or more vibration sensors is/are arranged for measuring the lateral vibration from the electric machine and for producing measured vibration data; and wherein the frequency converter is arranged for generating a control torque for exerting the control torque on the stator of the electric machine, the control torque being determined utilizing the measured vibration data.

Abstract: A field of electric drive devices, drivetrain systems and electric machines, such as electric motors and electric generators for industrial applications, and more particularly to a method, an arrangement, and a frequency converter for identification of torsional natural frequencies of a drivetrain system.

Abstract: An arrangement for monitoring an antifriction bearing of a rotating shaft of a rotating electric machine. The arrangement includes: one or more capacitor electrodes to measure a capacitive shaft displacement parameter; one or more of the following additional measurement sensors; a microphone to measure a bearing noise parameter, a voltage sensor to measure a bearing current parameter, and/or an optical pyrometer to measure a shaft heat parameter; and one or more processors configured to evaluate a condition of the antifriction bearing based on the capacitive shaft displacement parameter and one or more of the following: the bearing noise parameter, the bearing current parameter, and/or the shaft heat parameter.

Abstract: An electromechanical device having a mechanical interface structure for connecting to an external rotating element, an electrical machine, and one or more gear stages on a mechanical power transmission path between the mechanical interface structure and a rotor of the electrical machine. The electromechanical device also has bearings for connecting the rotor of the electrical machine rotatably to the structure of the electromechanical device. The bearings carry the axial and radial forces of the rotor, and at least partly the axial and radial forces of the driving shaft of the gear stage, directly connected to the rotor.

Abstract: An electromechanical device comprises a mechanical interface structure (101) for connecting to an external rotating element, for example a wind turbine. The device comprises an electrical machine (102-104), and one or more gear stages (105-112) on a power transmission path between the mechanical interface structure and a rotor of the electrical machine. The device further comprises mechanical structures (113-115) constituting a common lubricant oil room for both the gear stages and the electrical machine. The electromechanical device comprises oil channels (116a) for directing lubricant oil circulated in the device to flow via the gear stages and via bearings (118, 119) of the electrical machine. Therefore, a common lubricating system can be used for both the gear stages and the electrical machine.

Abstract: A method for installing a rotor of an electrical machine is disclosed. The method comprises using axially directed guide bars (107-109) for keeping the rotor (102) centered with respect to a bore of a stator (101) during the installation of the rotor. The rotor has sliding surfaces so that it can be slid in the axial direction to its final position along the guide bars. The mechanical support structure (104) that supports bearings (105, 106) of the rotor are provided with supporting surfaces for being able to give mechanical support to the guide bars. The mechanical support structure (104) may comprise for example threaded holes to which threaded ends of the guide bars can be tightened. After the rotor has been moved to its final position and it is supported by the bearings, the guide bars are removed.

Abstract: An electromechanical device having a mechanical interface structure for connecting to an external rotating element, an electrical machine, and one or more gear stages on a mechanical power transmission path between the mechanical interface structure and a rotor of the electrical machine. The rotor of the electrical machine is supported by the frame of the gear stage directly connected to the rotor.

Abstract: An electromechanical device comprising a mechanical interface structure (101) for connecting to an external rotating element, an electrical machine (102-104, 117), and one or more gear stages (105-112) on a mechanical power transmission path between the mechanical interface structure and a rotor of the electrical machine, wherein the electromechanical device further comprises a bearing means (118, 119) for connecting the rotor (103) of the electrical machine rotatably to the structure of the electromechanical device, which bearing means carry the axial and radial forces of the rotor and at least partly the axial and radial forces of the driving shaft (112) of the gear stage directly connected to the rotor.

Abstract: An electromechanical device comprising a mechanical interface structure (101) for connecting to an external rotating element, an electrical machine (102-104), and one or more gear stages (105-112) on a mechanical power transmission path between the mechanical interface structure and a rotor (103) of the electrical machine, wherein the rotor (103) of the electrical machine is supported by the frame of the gear stage directly connected to the rotor.

Abstract: A method for installing a rotor of an electrical machine is disclosed. The method comprises using axially directed guide bars (107-109) for keeping the rotor (102) centered with respect to a bore of a stator (101) during the installation of the rotor. The rotor has sliding surfaces so that it can be slid in the axial direction to its final position along the guide bars. The mechanical support structure (104) that supports bearings (105, 106) of the rotor are provided with supporting surfaces for being able to give mechanical support to the guide bars. The mechanical support structure (104) may comprise for example threaded holes to which threaded ends of the guide bars can be tightened. After the rotor has been moved to its final position and it is supported by the bearings, the guide bars are removed.

Abstract: An electromechanical device comprises a mechanical interface structure (101) for connecting to an external rotating element, for example a wind turbine. The device comprises an electrical machine (102-104), and one or more gear stages (105-112) on a power transmission path between the mechanical interface structure and a rotor of the electrical machine. The device further comprises mechanical structures (113-115) constituting a common lubricant oil room for both the gear stages and the electrical machine. The electromechanical device comprises oil channels (116a) for directing lubricant oil circulated in the device to flow via the gear stages and via bearings (118, 119) of the electrical machine. Therefore, a common lubricating system can be used for both the gear stages and the electrical machine.