Abstract: An inductive device comprises a toroidal core and at least one electric conductor wound around the toroidal core and constituting at least one winding. The inductive device comprises a cooling element constituting a cylindrical cavity that contains the toroidal core and the electric conductor so that the axial direction of the toroidal core is parallel with the axial direction of the cylindrical cavity. The shape of the cylindrical cavity and the cross-section of the electric conductor are adapted to match each other to improve heat transfer from the electric conductor to the wall of the cylindrical cavity so that a wall of the cylindrical cavity is provided with axially directed grooves occupied by portions of the electric conductor on an outer perimeter of the winding.

Abstract: A vessel includes electric connectors for receiving one or more direct voltages from a shore-side electric power system. The vessel includes a transmitter for transmitting, to the shore-side electric power system, a control signal enabling the shore-side electric power system to control the one or more direct voltages to be suitable for the vessel. Alternatively, the vessel includes one or more controllable direct voltage converters and a control system for controlling the one or more controllable direct voltage converters to convert the one or more direct voltages into one or more direct voltages suitable for the vessel. The vessel can be for example a ship, a boat, or a ferry.

Abstract: A power system for supplying electric power from shore-side to a vessel is presented. The power system includes one or more shore-side converters (101-112) for receiving electric power from a shore-side alternating voltage network (137) and for producing one or more direct voltages. Each shore-side converter can be a controllable converter for controlling the produced direct voltage to be suitable for the vessel in accordance with a control signal received from the vessel, or the vessel may include a direct voltage converter for converting the direct voltage received from the shore-side to be suitable for the vessel. The vessel can be an electric vessel which includes a chargeable battery (132) for supplying electric power to the propulsion system (135) of the vessel.

Abstract: A power converter for an electric power system comprises a switching circuit (102) for supplying, in a first operating mode of the power converter, voltages for driving a rotating electric machine. The power converter comprises a contactor system (110) and a controller (109) for using, in a second operating mode of the power converter, the switching circuit and at least one of windings (115) of the rotating electric machine as a voltage-decreasing direct voltage converter between direct voltage terminals of the power converter. Therefore, the switching circuit of the power converter can be utilized both for driving the rotating electric machine and, for example, for charging a battery element connected to a direct voltage terminal of the power converter.

Abstract: A working machine comprises a direct voltage source (301), a first power converter (302) for transferring energy from the direct voltage source to electric machines (303a, 303b) driving actuators of the working machine, an electric connector system (304) for electrically connecting to an external power grid, a second power converter (305) for transferring energy from the external power grid to the direct voltage source, and alternating current electric machines (306a, 306b) driving auxiliary devices of the working machine. The electric connector system is suitable for connecting the alternating current electric machines to receive alternating voltage of the external power grid, and the second power converter is suitable for transferring energy from the direct voltage source to the alternating current electric machines. Thus, the electric machines driving the auxiliary devices can be energized directly by the external power grid when the working machine is connected to the external power grid.

Abstract: A power converter comprises an inductor coil whose first pole is connected to an input terminal of the power converter, a controllable switch between the ground and a second pole of the inductor coil, a first unidirectionally conductive component providing a path for electric current from the inductor coil towards an output terminal of the power converter when the controllable switch is non-conductive, and an over-current protector at the output terminal. The power converter comprises a second unidirectionally conductive component for conducting electric current from the input terminal to the over-current protector in a fault situation where voltage at the output terminal is smaller than voltage at the input terminal. Thus, the second unidirectionally conductive component constitutes a low-inductance bypass route for fault current and enables the over-current protector to react fast to a fault situation.

Abstract: A vessel includes electric connectors for receiving one or more direct voltages from a shore-side electric power system. The vessel includes a transmitter for transmitting, to the shore-side electric power system, a control signal enabling the shore-side electric power system to control the one or more direct voltages to be suitable for the vessel. Alternatively, the vessel includes one or more controllable direct voltage converters and a control system for controlling the one or more controllable direct voltage converters to convert the one or more direct voltages into one or more direct voltages suitable for the vessel. The vessel can be for example a ship, a boat, or a ferry.

Abstract: A power converter for an electric power system comprises a switching circuit (102) for supplying, in a first operating mode of the power converter, voltages for driving a rotating electric machine. The power converter comprises a contactor system (110) and a controller (109) for using, in a second operating mode of the power converter, the switching circuit and at least one of windings (115) of the rotating electric machine as a voltage-decreasing direct voltage converter between direct voltage terminals of the power converter. Therefore, the switching circuit of the power converter can be utilized both for driving the rotating electric machine and, for example, for charging a battery element connected to a direct voltage terminal of the power converter.

Abstract: A working machine comprises a direct voltage source (301), a first power converter (302) for transferring energy from the direct voltage source to electric machines (303a, 303b) driving actuators of the working machine, an electric connector system (304) for electrically connecting to an external power grid, a second power converter (305) for transferring energy from the external power grid to the direct voltage source, and alternating current electric machines (306a, 306b) driving auxiliary devices of the working machine. The electric connector system is suitable for connecting the alternating current electric machines to receive alternating voltage of the external power grid, and the second power converter is suitable for transferring energy from the direct voltage source to the alternating current electric machines. Thus, the electric machines driving the auxiliary devices can be energized directly by the external power grid when the working machine is connected to the external power grid.

Abstract: An electric power system includes a direct voltage rail (101), battery elements (102-104) connected with supply-converters (105-107) to the direct voltage rail, and load-converters (111-113) for converting direct voltage of the direct voltage rail into voltages suitable for loads of the electric power system, where the supply-converters and the load-converters are connected with over-current protectors (108-110, 114-116) to the direct voltage rail. The electric power system further includes a capacitor system (117) connected to the direct voltage rail and capable of supplying fault current for switching an over-current protector into a non-conductive state in response to a fault causing a voltage drop at an electrical node connected to the direct voltage rail via the over-current protector. The capacitor system may include one or more high-capacitance electric double layer capacitors. The fault current available from the capacitor system enables a selective protection.

Abstract: A device (101) for producing a position signal indicative of rotational position of a resolver is presented. The device comprises a signal transfer interface (102) for receiving first and second alternative signals, and a processing system (103) for generating the position signal on the basis of the amplitudes of the first and second alternative signals and the polarity of an excitation signal of the resolver. The device is configurable to operate in a first operational mode where a local signal generator (104) generates the excitation signal and the device transmits the excitation signal to the resolver. The device is configurable to operate also in a second operational mode where the device receives information indicative of the polarity of the excitation signal from another device. Thus, devices of the kind described above can be used in a system where many converters are driving separate windings systems of an electrical machine.

Abstract: A power converter comprises an inductor coil whose first pole is connected to an input terminal of the power converter, a controllable switch between the ground and a second pole of the inductor coil, a first unidirectionally conductive component providing a path for electric current from the inductor coil towards an output terminal of the power converter when the controllable switch is non-conductive, and an over-current protector at the output terminal. The power converter comprises a second unidirectionally conductive component for conducting electric current from the input terminal to the over-current protector in a fault situation where voltage at the output terminal is smaller than voltage at the input terminal. Thus, the second unidirectionally conductive component constitutes a low-inductance bypass route for fault current and enables the over-current protector to react fast to a fault situation.

Abstract: An inductive device includes a toroidal core and at least one electric conductor wound around the toroidal core and constituting at least one winding. The inductive device includes a cooling element constituting a cylindrical cavity that contains the toroidal core and the electric conductor so that the axial direction of the toroidal core is parallel with the axial direction of the cylindrical cavity. The shape of the cylindrical cavity and the cross-section of the electric conductor are adapted to match each other so as to improve heat transfer from the electric conductor to the wall of the cylindrical cavity. The cylindrical cavity can have for example a circular base and the electric conductor can have for example a rectangular cross-section that matches the shape of the wall of the cylindrical cavity better than a round electric conductor.

Abstract: An electromechanical power transmission chain comprises an electrical machine (101) connectable to a combustion engine and to a mechanical load, a storage circuit (104) for storing electrical energy, an electronic power converter (109) for transferring electrical energy between the storage circuit and the electrical machine, and a control system (110) for controlling the combustion engine and the electronic power converter. The control system controls the electronic power converter to transfer electrical energy from the storage circuit to the electrical machine in response to a peak-load situation where power demand of the mechanical load is above an advantageous power range of the combustion engine. The control system limits the fuel supply of the combustion engine during the peak-load situation so as to restrain the fuel consumption from increasing due to the peak-load situation.

Abstract: A capacitor module includes at least one capacitor element (101) and a cooling structure (103) for cooling the capacitor element. The electrical terminals (102a, 102b) of the capacitor element are mechanically connected to the cooling structure to be in heat-conductive relations with the cooling structure so that at least one of the electrical terminals of the capacitor element is mechanically connected to the cooling structure via a flexible connection element (104a, 104b) made of electrically conductive material. The flexible connection element allows the corresponding electrical terminal to move with respect to the cooling structure when the distance (D) between the electrical terminals is changing because of changes in load and/or temperature, and/or because of ageing.

Abstract: A power system for supplying electric power from shore-side to a vessel is presented. The power system includes one or more shore-side converters (101-112) for receiving electric power from a shore-side alternating voltage network (137) and for producing one or more direct voltages. Each shore-side converter can be a controllable converter for controlling the produced direct voltage to be suitable for the vessel in accordance with a control signal received from the vessel, or the vessel may include a direct voltage converter for converting the direct voltage received from the shore-side to be suitable for the vessel. The vessel can be an electric vessel which includes a chargeable battery (132) for supplying electric power to the propulsion system (135) of the vessel.

Abstract: An electric power system includes a direct voltage rail (101), battery elements (102-104) connected with supply-converters (105-107) to the direct voltage rail, and load-converters (111-113) for converting direct voltage of the direct voltage rail into voltages suitable for loads of the electric power system, where the supply-converters and the load-converters are connected with over-current protectors (108-110, 114-116) to the direct voltage rail. The electric power system further includes a capacitor system (117) connected to the direct voltage rail and capable of supplying fault current for switching an over-current protector into a non-conductive state in response to a fault causing a voltage drop at an electrical node connected to the direct voltage rail via the over-current protector. The capacitor system may include one or more high-capacitance electric double layer capacitors. The fault current available from the capacitor system enables a selective protection.

Abstract: A capacitor module includes a capacitor element, a first voltage terminal connected to a first pole of the capacitor element, and a second voltage terminal connected to a second pole of the capacitor element. The capacitor module further includes a cooling duct system for cooling the capacitor element, and a housing encapsulating the capacitor element and the cooling duct system. The housing comprises wiring lead-throughs for the first and second voltage terminals and piping lead-throughs for the cooling duct system. As the capacitive module is encapsulated and includes the cooling ducts and the wiring and piping lead-throughs, modular capacitive energy-storages of different sizes can be built by interconnecting capacitor modules of the kind described above, and there is no need to build separately an encapsulation provided with cooling ducts.

Abstract: A device (101) for producing a position signal indicative of rotational position of a resolver is presented. The device comprises a signal transfer interface (102) for receiving first and second alternative signals, and a processing system (103) for generating the position signal on the basis of the amplitudes of the first and second alternative signals and the polarity of an excitation signal of the resolver. The device is configurable to operate in a first operational mode where a local signal generator (104) generates the excitation signal and the device transmits the excitation signal to the resolver. The device is configurable to operate also in a second operational mode where the device receives information indicative of the polarity of the excitation signal from another device. Thus, devices of the kind described above can be used in a system where many converters are driving separate windings systems of an electrical machine.

Abstract: An electromechanical power transmission chain comprises an electrical machine (101) connectable to a combustion engine and to a mechanical load, a storage circuit (104) for storing electrical energy, an electronic power converter (109) for transferring electrical energy between the storage circuit and the electrical machine, and a control system (110) for controlling the combustion engine and the electronic power converter. The control system controls the electronic power converter to transfer electrical energy from the storage circuit to the electrical machine in response to a peak-load situation where power demand of the mechanical load is above an advantageous power range of the combustion engine. The control system limits the fuel supply of the combustion engine during the peak-load situation so as to restrain the fuel consumption from increasing due to the peak-load situation.