Abstract: A method and an apparatus for controlling a fan motor which is arranged to arranged to cool an object to be cooled and to be controlled by an inverter whose output is connected to the fan motor. The method of the invention comprises steps of determining the temperature of the object to be cooled or a variable proportional to the temperature to form a control variable, controlling the frequency of the inverter output voltage on the basis of the control variable, and controlling the effective value of the inverter output voltage on the basis of the control variable.

Abstract: Control circuit for an IGB transistor, which comprises means (T1, V1, C3, C4) for generating auxiliary voltage, a first and a second controllable control switches (V8) connected in series between the auxiliary voltage, and a gate resistor (Rg). The control circuit further comprises a boost capacitor (Cg) connected in series with the gate resistor (Rg), a resistor (R3) whose first terminal is connected to the second terminal (4) of the boost capacitor and whose second terminal is connected to the intermediate voltage level of the auxiliary voltage of the control switches, a Zener diode (V9) whose anode is connected to the point between the gate resistor and the boost capacitor and whose cathode is connected to the point between the boost capacitor and the resistor (R3), and a diode (V10) whose anode is connected to the cathode of the Zener diode (V9) and whose cathode is connected to the positive terminal of the auxiliary voltage of the control switches.

Abstract: A method of controlling a half-controlled rectifier, and a rectifier structure, which comprises an n-phased half-controlled converter bridge, a DC intermediate circuit and a capacitor of the DC intermediate circuit. The converter structure further comprises an auxiliary intermediate circuit and a non-controlled n-phased diode rectifier bridge which feeds the auxiliary intermediate circuit and is connected to the DC intermediate circuit by isolating diodes.

Abstract: A method of controlling a half-controlled rectifier, and a rectifier structure, which comprises an n-phased half-controlled converter bridge, a DC intermediate circuit and a capacitor of the DC intermediate circuit. The converter structure further comprises an auxiliary intermediate circuit and a non-controlled n-phased diode rectifier bridge which feeds the auxiliary intermediate circuit and is connected to the DC intermediate circuit by isolating diodes.

Abstract: A method and an apparatus for controlling a fan motor which is arranged to arranged to cool an object to be cooled and to be controlled by an inverter whose output is connected to the fan motor. The method of the invention comprises steps of determining the temperature of the object to be cooled or a variable proportional to the temperature to form a control variable, controlling the frequency of the inverter output voltage on the basis of the control variable, and controlling the effective value of the inverter output voltage on the basis of the control variable.

Abstract: An inductor arrangement for a frequency converter or corresponding electrical apparatus, the inductor arrangement comprising an input inductor coupled to the input side of the electrical apparatus and an output inductor coupled to the output side of the apparatus, the input inductor comprising a core element having yokes and columns, and several winding turns for each phase formed around the core element. The output inductor is provided in the inductor arrangement by placing a predetermined length of a conductor of each phase in the output of said electrical apparatus adjacent to the core element of the input inductor.

Abstract: A charging contactor and charging resistor of a capacitor battery in a prior art intermediate circuit of a frequency converter are replaced with three semiconductor switches connected between a three-phase voltage supply and a capacitor battery. When the frequency converter is connected to a supply network, the three semiconductor switches are arranged to operate at first in a current regulating mode in order to charge the capacitor battery using a regulated charging current until the voltage of the capacitor battery reaches a predetermined level. After this, the three semiconductor switches are directed to operate in a diode bridge mode in parallel with an actual network inverter, thus providing a second rectification branch. In a preferred embodiment of the invention, each semiconductor switch comprises a diode and a series connection of a gate-triggered component, preferably a thyristor.

Abstract: A method for manufacturing cooling elements for power electronic components and other cooling devices for electronic appliances, wherein molten metal is fed into a closed mould including a core part and a mould part. The metal is allowed to become solid whereafter the finished casting is removed from the mould. An insert package is assembled of lamellas made from a material which at least essentially corresponds to the casting material by pressing together several lamellas arranged next to one another such that an air slot remains between the lamellas arrranged next to one another such that an air slot remains between the lamellas. This insert package is machined such that it fits into a recess in the core part and the insert and the insert package is placed in the recess in the core part before closing the mould, whereby the package is fastened to the casting once the mould has been filled.

Abstract: A galvanic isolation coupling of a current loop comprising an operational amplifier (A1) as a part of the current loop and an optoisolator (1) comprising two receivers.

Abstract: A method and arrangement for determining state information of a high-power semi-conductor, the power semiconductor comprising a collector (C), an emitter (E) and a gate (G), and a gate driver (3) comprising an auxiliary voltage input is connected to the gate of the power semiconductor. The method is characterized by steps wherein the auxiliary voltage (Vcc) of the gate driver (3) is used as reference voltage, saturation voltage (Vsat) of the power semiconductor (1) is compared with the reference voltage by using an optoisolator (4), and a detection signal of state information is generated depending on the magnitudes of the saturation voltage and the reference voltage.

Abstract: A stabilized gate driver which comprises a current source transformer (T) which comprises a primary and a secondary coil, and a gate driver unit (GD) which includes a positive auxiliary voltage input (Va+) and a negative auxiliary voltage input (Va−).

Abstract: A control circuit for controlling a semiconductor component (2) comprising an emitter (E), a collector (C) and a gate (G), the control circuit comprising a gate driver (GD) the output of which is connected to the gate (G) of the semiconductor component to be controlled. The control circuit further comprises a resistance coupling (1) where two series connections of a diode (V1, V2) and a resistor (R1, R2) are in an antiparallel connection and connected between the emitter (E) of the semiconductor component (2) and the zero potential (Com) of the gate driver (GD), and a feedback capacitor (C1) connected between the collector (C) of the semiconductor component (2) and the end of the resistance coupling (1) connected to the zero potential (Com) of the gate driver.

Abstract: A control circuit for controlling a power semiconductor, the control circuit comprising a gate driver comprising a control input, auxiliary voltage inputs and an output. The control circuit further comprises a first semiconductor switch comprising a control electrode and main electrodes, a first main electrode forming a positive input pole of the control circuit and a second forming an output of the control circuit; a second semiconductor switch comprising a control electrode and main electrodes, a first main electrode forming a negative input pole of the control circuit and a second being connected to the output of the control circuit; a first resistance, a second resistance, a first zener diode whose anode is connected to the output of the gate driver and whose cathode to the positive input pole of the control circuit; and a second zener diode whose cathode is connected to the output of the gate driver and whose anode to the negative input pole of the control circuit.

Abstract: An inverter has a direct voltage intermediate circuit having a positive (Udc+) and a negative (Udc-) voltage busbar, and an auxiliary voltage source (1) which generates auxiliary voltages (U1, U2, U3) referenced to the positive (Udc+) and the negative (Udc-) voltage busbar of the direct voltage intermediate circuit. The inverter also has for each phase an upper (2) and a lower (3) power semiconductor, connected in series between the positive and the negative voltage busbar. The point between the semiconductors forms the phase output (Uout) of the inverter. An upper (4) and lower (5) gate driver outputs (8,9) are connected to the control electrode (G) of the respective upper (2) and lower (3) power semiconductors which have a positive (6) and a negative (7) auxiliary voltage input and a zero potential point (Com) connected to the output electrode (E) of the power semiconductor to be controlled.

Abstract: The invention relates to a connector and a manufacturing method thereof for a three-phase cable including concentric, segmentally disposed phase conductors (1) with surrounding insulation structures (11) and a concentric earth conductor (8) enclosing the phase conductors. According to the invention, the phase conductors (1) inside the connector are isolated from each other by a star-shaped dividing insulation piece (3) keeping the phase conductors (1) separate in their segments. Phase terminals (2) of the connector are disposed on the segment bottoms of the dividing insulation piece (3). The connector further incorporates a clamp (5, 7) suited for pressing the phase conductors (1) against the phase terminals (2) and a ferrule (10) on which the earth conductor (8) can be bent backward to mechanically lock a receptacle.

Abstract: The invention relates to a control circuit for a semiconductor switch, comprising a transformer coupling (T1, T2) for generating AC voltage signals including both control energy and control information, a rectification coupling (DB1, DB2) for rectifying the AC voltage signals generated by the transformer coupling (T1, T2) for generating DC voltage levels (U1, U2, U3) appropriate for turning on and turning off a semiconductor switch (SW1), a first resistor (R2) connected at its first end to a driving electrode of the semiconductor switch (SW1), a second resistor (R1) connected between the driving electrode and the emitter or source electrode of the semiconductor switch, and a booster semiconductor switch (V1) provided between the driving electrode of the semiconductor switch (SW1) and an DC voltage output (U3) generated by the rectification coupling and intended for turning off the semiconductor switch, the driving electrode of the booster semiconductor (V1) being connected to a DC voltage output (U2) generate

Abstract: The invention relates to a semiconductor switch control circuit comprising a timing logic unit (1), a first and a second driver (2, 3) controlled by the timing logic unit, a first and a second transformer (T1, T2), to which the first and the second driver (2, 3), respectively, apply an unmodulated ac voltage signal (A, B) for bringing the semiconductor switch into a conducting and non-conducting state, respectively, and the secondary windings of which are connected at the opposite ends to a reference potential (RP); a first and a second rectifier (4, 5) for rectifying dc voltages (V+, V-) of opposite polarity from a voltage (A, B) acting across the secondary windings of the transformers; a first and a second driver (10, 11) for maintaining the semiconductor switch (12) in a conducting and non-conducting state, respectively; and capacitor units (8, 9) for storing the turn-on and turn-off energy of the semiconductor switch, respectively.