Abstract: A converter arrangement can include a first rectifier having an AC input and a DC output with two DC output poles, a capacitance (C) connected between the DC output poles of the first rectifier, a second rectifier having an AC input with two AC input poles and a DC output with two DC output poles, wherein the DC output of the second rectifier is connected between the DC output poles of the first rectifier. A magnetic amplifier includes at least one control winding (L2) and at least one AC winding (L11, L12), wherein the at least one control winding is connected between the DC output poles of the first rectifier, and wherein the at least one AC winding (L2) of the magnetic amplifier is connected in series with the AC input of the second rectifier.

Abstract: A method and arrangement are disclosed for a vehicle inverter drive having a voltage distribution block and two or more inverters, intermediate circuits of which are connected in parallel to the voltage distribution block for supplying voltage to the intermediate circuits, in which the intermediate circuits of the inverters are interconnected with a coaxial cable to minimize inductance in the parallel connection.

Abstract: An exemplary method for charging a capacitance connected between DC poles of a three-phase active rectifier/inverter and a converter apparatus including a three-phase active rectifier/inverter having a capacitance connected between DC poles thereof, a three-phase filter and a three-phase step-down transformer. The active rectifier/inverter is configured to charge the capacitance connected between the DC poles of the active rectifier/inverter with a rectified secondary voltage of the transformer until a voltage of the capacitance reaches a first predetermined threshold voltage. In response to the voltage of the capacitance connected between the DC poles of the active rectifier/inverter reaching the first predetermined threshold voltage, the active/rectifier/inverter is configured to charge the capacitance with a boosted rectified secondary voltage of the transformer until the voltage of the capacitance reaches a second predetermined threshold voltage higher than the first predetermined threshold voltage.

Abstract: A converter arrangement can include a first rectifier having an AC input and a DC output with two DC output poles, a capacitance (C) connected between the DC output poles of the first rectifier, a second rectifier having an AC input with two AC input poles and a DC output with two DC output poles, wherein the DC output of the second rectifier is connected between the DC output poles of the first rectifier. A magnetic amplifier includes at least one control winding (L2) and at least one AC winding (L11, L12), wherein the at least one control winding is connected between the DC output poles of the first rectifier, and wherein the at least one AC winding (L2) of the magnetic amplifier is connected in series with the AC input of the second rectifier.

Abstract: A method and arrangement for preventing slip in a wheeled vehicle having two or more driving wheels that are operated with electric motors. The motor of each driving wheel includes a torque limit applicable to limit torque of the motor. For each driving wheel, the method includes setting an angular acceleration limit for the wheel, detecting angular acceleration of the driving wheel continuously, comparing the detected angular acceleration with the angular acceleration limit continuously, if the detected angular acceleration is higher than the angular acceleration limit, reducing the torque limit from its current value until the angular acceleration of the wheel is below the angular acceleration limit, increasing the torque limit at a first rate to a value lower than the value from which it was reduced, and increasing the torque limit at a second rate to the maximum value, the second rate being lower than the first rate.

Abstract: A method and arrangement for preventing slip in a wheeled vehicle having two or more driving wheels that are operated with electric motors. The motor of each driving wheel includes a torque limit applicable to limit torque of the motor. For each driving wheel, the method includes setting an angular acceleration limit for the wheel, detecting angular acceleration of the driving wheel continuously, comparing the detected angular acceleration with the angular acceleration limit continuously, if the detected angular acceleration is higher than the angular acceleration limit, reducing the torque limit from its current value until the angular acceleration of the wheel is below the angular acceleration limit, increasing the torque limit at a first rate to a value lower than the value from which it was reduced, and increasing the torque limit at a second rate to the maximum value, the second rate being lower than the first rate.

Abstract: A control system for semiconductor switches, the control system (CTRL) being configured to calculate an estimate of the instantaneous dissipation power of at least one semiconductor component unit (SU1) during an analysis period, whereby the at least one semiconductor component unit (SU1) includes at least one semiconductor switch (S1), and the instantaneous dissipation power includes the conduction losses and switching losses of the at least one semiconductor component unit (SU1).

Abstract: A method and arrangement are disclosed for a vehicle inverter drive having a voltage distribution block and two or more inverters, intermediate circuits of which are connected in parallel to the voltage distribution block for supplying voltage to the intermediate circuits, in which the intermediate circuits of the inverters are interconnected with a coaxial cable to minimize inductance in the parallel connection.

Abstract: A coil includes electrically conductive winding wire wound in turns around a core in one or more layers. The surface of the winding wire is provided with at least one groove in the direction of the longitudinal axis of the winding wire, and at least one cooling tube which enables coolant circulation is positioned in the groove of the winding wire, being at least partly embedded therein. The groove is formed on the surface of the winding wire of an outermost winding wire layer relative to the core and opens away from the core The cooling tube in the groove is placed around the outermost winding wire layer and covers the outermost winding wire layer at least partly.

Abstract: A mechanical construction of an electrical module includes two or more electrical components (102-105). Each of the electrical components has a contact surface (106-109) that is capable of forming a galvanic contact with an external electrical conductor. The electrical module includes a holder element (101) that includes flexible material arranged to flexibly support the electrical components with respect to each other in such a way that the contact surfaces of the electrical components are capable of aligning with external surfaces independently of each other.

Abstract: A coil includes electrically conductive winding wire wound in turns around a core in one or more layers. The surface of the winding wire is provided with at least one groove in the direction of the longitudinal axis of the winding wire, and at least one cooling tube which enables coolant circulation is positioned in the groove of the winding wire, being at least partly embedded therein. The groove is formed on the surface of the winding wire of an outermost winding wire layer relative to the core and opens away from the core The cooling tube in the groove is placed around the outermost winding wire layer and covers the outermost winding wire layer at least partly.

Abstract: A method and an apparatus for damping voltage oscillation of a voltage intermediate circuit of a frequency converter, the frequency converter comprising a half controlled rectifier bridge coupled to a supply network. The method comprises determining magnitude (Uc) of voltage of the voltage intermediate circuit, determining magnitude (Uin) of rectified voltage of the supply network, forming a derivative of a difference (Uin?Uc) between the rectified voltage of the supply network and the voltage of the voltage intermediate circuit, delaying firing of controllable components of the rectifier bridge on the basis of the formed derivative.

Abstract: A method for controlling brake resistors and a brake chopper, the number of brake resistors being two or more and the brake resistors being connected in series with switches to be controlled, the series connection being connected between a positive and a negative rail of a DC voltage intermediate circuit, the method comprising the step of determining a magnitude for a voltage of the DC intermediate circuit; and determining a first voltage limit and a second voltage limit. The method further comprises the steps of switching brake resistors to the intermediate circuit in a periodically alternating manner, each switch being switched during a switching period and the on-period of each switch in a switching period being responsive to the magnitude of the voltage in the DC voltage intermediate circuit when the voltage is above the first predetermined limit and below the second predetermined limit.

Abstract: The invention relates to a frequency converter, comprising: a power electronics part provided with wheels on the lower part thereof; an installation cabinet for receiving the power electronics part movable on the wheels; and connectors arranged to the power electronics part and the installation cabinet, a contact being created between the connectors when the power electronics part is installed into the installation cabinet. To facilitate electrical installation works, the power electronics part is divided at least into a base part provided with wheels and a power stage part arranged thereon, the two being detachably attached together, whereby the base part, when detached from the power stage part, can be pulled out of the installation cabinet whereas the power stage part remains in place in the installation cabinet.

Abstract: A mechanical construction of an electrical module includes two or more electrical components (102-105). Each of the electrical components has a contact surface (106-109) that is capable of forming a galvanic contact with an external electrical conductor. The electrical module includes a holder element (101) that includes flexible material arranged to flexibly support the electrical components with respect to each other in such a way that the contact surfaces of the electrical components are capable of aligning with external surfaces independently of each other.

Abstract: A method and an apparatus for damping voltage oscillation of a voltage intermediate circuit of a frequency converter, the frequency converter comprising a half controlled rectifier bridge coupled to a supply network. The method comprises determining magnitude (Uc) of voltage of the voltage intermediate circuit, determining magnitude (Uin) of rectified voltage of the supply network, forming a derivative of a difference (Uin?Uc) between the rectified voltage of the supply network and the voltage of the voltage intermediate circuit, delaying firing of controllable components of the rectifier bridge on the basis of the formed derivative.

Abstract: A method and an arrangement for charging capacitors of a direct-voltage intermediate circuit of a frequency converter. The arrangement comprises a charging circuit (CCA) comprising a first diode (D1) and a second diode (D2) connected in series with the first diode (D1) and a current-limiting component (AA) connected in parallel with the series connection of the diodes (D1, D2), whereby said capacitors may be charged through a main switch (K1b, K2b, . . . , Knb) of the capacitor, the first diode (D1) and the current-limiting component (AA).

Abstract: This publication discloses a switching device combination for capacitive loads (3) connected to a direct voltage. The switching device combination includes an actual switch component (1) for connecting voltage to the capacitive load (3), a charging switch component (2) for connecting charging voltage to the capacitive load in the initial stage, which charging switch component is dimensioned for a lower current than the actual switch component (1), a controller component (4), by means of which the actual switch component (1) is controlled from an open state to a closed state and vice versa, with the aid of a mechanical lever (5), which is connected to a first shaft (6), and delay elements (11) for delaying the connection of the actual switch component (1), so that the closed charging switch component (2) will have time to charge the capacitive load (3) before the connection of the actual switch component (1).

Abstract: The invention relates to a frequency converter, comprising: a power electronics part provided with wheels on the lower part thereof; an installation cabinet for receiving the power electronics part movable on the wheels; and connectors arranged to the power electronics part and the installation cabinet, a contact being created between the connectors when the power electronics part is installed into the installation cabinet. To facilitate electrical installation works, the power electronics part is divided at least into a base part provided with wheels and a power stage part arranged thereon, the two being detachably attached together, whereby the base part, when detached from the power stage part, can be pulled out of the installation cabinet whereas the power stage part remains in place in the installation cabinet.

Abstract: A cooled multiphase choke assembly comprising a first coil (L1, L2, L3) for each phase (U, V, W) and a first cooling element (11), each first coil (L1, L2, L3) comprising several turns of winding, which define a substantially tubular tunnel inside each coil (L1, L2, L3). The first cooling element (11) extends in the tubular tunnel of each first coil (L1, L2, L3).