Abstract: An actuator assembly is disclosed, which includes a power unit, an actuator powered by the power unit, the power unit being configured to provide a work motion of the actuator, a motion sensor, a timing unit for measuring an immobility time of the actuator, a safety unit for selectively placing the actuator assembly into an operational state and a safety state in which the work motion of the actuator can be prevented, the safety unit being configured to prevent the operational state of the actuator assembly in case the immobility time of the actuator exceeds a predetermined process safety time. The actuator assembly can include an activation unit configured to control the power unit to provide an activation motion of the actuator in case the immobility time exceeds a predetermined activation time.

Abstract: A three-level converter and a method for controlling a three-level converter, wherein the third (S31, S32, S33), the fourth (S41, S42, S43) and the fifth (S51, S52, S53) controllable semiconductor switch of a switching branch having, out of all the switching branches, the most positive voltage in its alternating current pole (AC1, AC2, AC3) is controlled to be non-conductive for the whole period of time when the switching branch in question has the most positive voltage in its alternating current pole, and the first (S11, S12, S13), the second (S21, S22, S23) and the sixth (S61, S62, S63) controllable semiconductor switch of a switching branch having, out of all the switching branches, the most negative voltage in its alternating current pole is controlled to be non-conductive for the whole period of time when the switching branch in question has the most negative voltage in its alternating current pole.

Abstract: Unique systems, methods, techniques and apparatuses of a reverse-conducting IGBT (RC-IGBT) are disclosed. One exemplary embodiment is a circuit comprising a series connection of controllable switch components where at least one of the controllable switch components is an RC-IGBT. The circuit is operated by applying a pre-trigger pulse to the gate electrode of the RC-IGBT during reverse conduction of the RC-IGBT at a first time instant, the pre-trigger pulse corresponding to a turn-on gate pulse. Next, a turn-on gate pulse is applied at a second time instant to the other controllable switch component of the series connection for controlling the other controllable switch component to a conductive state such that the pre-trigger pulse and the turn-on gate pulse overlap, and ending the pre-trigger pulse after a delay time at the third time instant. The delay time is the time period when the turn-on gate pulse and the pre-trigger pulse overlap.

Abstract: A method is provided for optimizing a parameter used in a frequency converter connected to an electrical rotating machine. The method includes identifying a parameter of the machine using electrical quantities, the identified parameter being used in the frequency converter and being identified in a first operating point, providing an electro-mechanical model of the rotating electrical machine to the frequency converter, and calculating when a processor capacity of the frequency converter is available, (i) a state of the rotating electrical machine in the first operating point using a finite element method with the electro-mechanical model of the rotating electrical machine, (ii) a state of the rotating electrical machine in a selected operating point using the finite element method with the electro-mechanical model, correcting the calculated state of the rotating electrical machine, and calculating, from the corrected state, parameter(s) of the electrical machine to be used in the frequency converter.

Abstract: The present disclosure relates to a power semiconductor module comprising a printed circuit board (PCB), and to method of cooling such a power semiconductor module. The module comprises a power semiconductor device and an island of thermally conducting foam embedded into the printed circuit board. The power semiconductor device and the island of thermally conducting foam are positioned on top of each other, and the island is arranged to form a path for a flowing coolant cooling the power semiconductor device.

Abstract: An enclosure, wherein the enclosure is at least partly formed of a layered material (3), the inner layer (1) of the layered material being formed of porous metal and the outer layer (2) of the layered material being formed of hygroscopic porous material.

Abstract: A method is provided for balancing voltages of a DC link of a multi-level inverter, where the DC link is divided into two halves by a neutral point connection. The method includes injecting a periodic common-mode voltage injection signal to a common-mode voltage reference and a periodic power injection signal to a power reference of the inverter. The power injection signal has the same frequency as the common-mode voltage injection signal. A phase shift between the common-mode voltage injection signal and the power injection signal is constant. The amplitude of at least one of the common-mode voltage injection signal and the power injection signal is controlled on the basis of a difference between voltages over the two halves of the DC link. An apparatus is also provided for implementing the method.

Abstract: An exemplary method for determining a flow rate of a pump, includes measuring and storing the flow rate (QMean) when the pump is in operation, storing rotational speed (nMean) and torque (TMean) of the pump during measurement of the flow rate (QMean), determining torque (TManufacturer) corresponding to the measured flow rate (QMean), calculating a bias value of the torque (TBias) by comparing the torque determined from the characteristic curve (TManufacturer) and the stored torque (TMean) of the pump, and determining an operating point of the pump based on the bias value of the torque (TBias).

Abstract: An exemplary arrangement and method for a power semiconductor switch, where a first current between a first electrode and a second electrode can be controlled based on a control voltage between a third electrode and the first electrode. The arrangement includes an inductance connected in series with the power semiconductor switch, wherein a first end of the inductance is connected to the first electrode, first measuring source for generating a first measurement voltage based on the first end's voltage with respect to a reference potential, second measuring source for generating a second measurement voltage on the basis of the inductance's second end voltage with respect to the reference potential, a comparator for comparing the first measurement voltage with the second measurement voltage, and driver for generating the control voltage. The driver being configured to generate a first control voltage level and a second voltage level of the control voltage.

Abstract: A method and device are disclosed for synchronizing an inverter with an alternating voltage source. The method includes measuring a current generated by the alternating voltage source and flowing through diodes of the inverter, determining a phase angle and angular velocity relating to the alternating voltage source from the measured current for enabling synchronization between the inverter and the alternating voltage source, and starting modulation of the inverter according to the obtained phase angle and angular velocity.

Abstract: The present disclosure is directed to a method and apparatus for approximating a static head of a fluid transfer system including a fluid transfer device. The method can include determining a rotational speed and a power consumption of the fluid transfer device, determining a first set of data points, calculating a second set of data points on the basis of the first set of data points, determining a minimum rotational speed producing flow through the fluid transfer device on the basis of the second set of data points, and determining the static head on the basis of the minimum rotational speed.

Abstract: Exemplary embodiments are directed to an equipment space that is a closed space provided with electrical equipment and an air dryer condensing the moisture of the air in the equipment space into water. A system for removing water from the equipment space includes a porous element having a capillary structure and being located in an outlet opening of the equipment space. The porous element is connected such that water condensed by the air dryer is directed to a first inner surface of the porous element. The capillary structure of the porous element is configured to propogate water from the inner surface of the porous element to an outer surface of the porous element. The outer surface of the porous element is configured to release water to ambient air outside the equipment space.

Abstract: An exemplary method and arrangement for balancing currents of power semiconductors. The arrangement including multiple power semiconductor units and a central control unit. Each power semiconductor unit includes a power semiconductor and the central control unit and the power semiconductor units are arranged in a bi-directional ring, in which the central control unit sends control information for the power semiconductor units in both directions in the bi-directional ring and each power semiconductor unit receives the control information in both directions and forwards the received control information.

Abstract: A switching branch for a three-level inverter, comprising a first and second switch (S1, S2) in series between a positive DC pole (P) and an AC pole (AC), a first and second diode (D1, D2) parallel to the first and second switches, a third and fourth switch (S3, S4) in series between a negative DC pole (N) and the AC pole, a third and fourth diode (D3, D4) parallel to the third and fourth switches, a fifth diode (D5) between a neutral DC pole (M) and a point between the first and second switches, a sixth diode (D6) between the neutral DC pole and a point between the third and fourth switches, a fifth switch (S5) and a seventh diode (D7) in series between the neutral DC and AC poles, and a sixth switch (S6) and an eighth diode (D8) in series between the neutral DC and AC poles.

Abstract: An electronic device including a sealed enclosure, the electronic components arranged inside the sealed enclosure and including high-loss high-temperature components, a main heat sink including ribs, wherein the high-loss high-temperature components are attached to the main heat sink and the ribs of the main heat sink are arranged outside the enclosure, a cavity formed inside the enclosure and divided into a plurality of channel-like sections, the channel-like sections configured for providing air flow guidance inside the enclosure and being interconnected at their ends, wherein at least one channel-like section contains the electronic components and at least one other channel-like section contains an air-to-air heat exchanger extending from inside the sealed enclosure to outside of the sealed enclosure, wherein the electronic components inside the at least one channel like section are adapted to be cooled by air flow inside the sealed enclosure.