Abstract: An installation for transmission of high-voltage direct current comprises a first and a second converter (SR1, SR2, respectively), each one controlled by a separate piece of control equipment (CE1, CE2, respectively). Each one of the pieces of control equipment comprises a current controller (CC). The current controller of the second converter is supplied with a second current reference value (IOL2) and a current margin (IOM). The control equipment of the second converter comprises a function-forming member (11), which in dependence on an applied measured value (UD) of the direct voltage forms the current margin such that, when the direct voltage exceeds a first preselected voltage level (Udf), it assumes a first value (IOMf) and, when the direct voltage is lower than the first voltage level, it assumes a second value (IOMs), the magnitude of the second value being greater than the magnitude of the first value.

Abstract: The invention relates to a control system for an industrial robot adapted for storage of user programs which comprise a series of robot instructions. At least one of the robot instructions is arranged as a shell instruction, which constitutes a call to a shell routine (20). The shell routine is associated with a plurality of optional attributes (21a, 21b, 21c) and comprises- a forward list (22) comprising a first set of robot instructions; and- a backward list (23) comprising a second set of robot instructions.The control system comprises a program executor adapted, for forward running of a user program, to execute the shell instructions in accordance with the forward list and, for running the user program backwards, to execute the shell instructions in accordance with the backward list.The invention also relates to a method for controlling an industrial robot. The method comprises creating a plurality of shell routines and testing them in advance.

Abstract: A surge arrester includes a stack of varistor blocks (10), for example of zinc oxide, arranged between two end electrodes (11, 12) in an elongated insulating casing (23) of polymeric material, for example silicone rubber. The varistor blocks and the electrodes are axially surrounded by compression loops (14-17) of insulating material for providing the necessary contact pressure between the different elements (10, 11, 12) in the varistor stack. The varistor stack (10) and the compression loops are radially surrounded by a bursting-preventive bandage (21) of insulating material with openings (22) for pressure relief in case of internal short circuit in the surge arrester.

Abstract: An optoelectronic component includes a housing having a first body and a second, spherical body, and an optoelectronic semiconductor element mounted in the second, spherical body. The second, spherical body is adjustably journalled in a cylindrical recess of the first body. The cylindrical recess includes an opening edge and the spherical body includes a portion having substantially the same outer periphery diameter as the diameter of the cylindrical recess at the level with the opening edge of the cylindrical body. A welded joint extends around the whole opening edge to provide a hermetically sealed joint between the opening edge and that portion of the spherical body.

Abstract: A device in a system for power transmission by means of high voltage direct current wherein: a first current path and a second current path are interconnected at a branch point; a first semiconductor connection is connected into the first current path only and which is controllable between conducting and non-conducting states and vice versa; a second semiconductor connection having a diode function and which is connected into the second current path only; a capacitor branch comprising a capacitor and connected between a first connection point on the first current path and a second connection point on the second current path; the first connection point and the branch point are located on opposite sides of the first semiconductor connection; the second connection point and the branch point are located on opposite sides of the second semiconductor connection; and control members for controlling, in dependence on the voltage across the capacitor, the first semiconductor connection between a non-conducting and a c

Abstract: A method for controlling an industrial robot such that a tool supported by the robot is able to follow a path which is determined by a number of consecutive points, and wherein the robot while following the path ends up near or a singularity. The robot has a plurality of movement axes and its configuration is determined by the angles of rotation of the movement axes. The angles of rotation which are to be assumed by the robot in order to obtain the desired position and orientation for the tool at the next point on the path are calculated by an iterative method. The ratio of the angular velocities of the axes to the velocity of the tool is given by a Jacobian matrix. By means of the Jacobian matrix it is determined whether the robot is at or near a singularity. The intention of the invention is to control the iteration such that the position of the tool remains correct through the singularity. A certain error in the orientation of the tool may be accepted.

Abstract: The present invention relates to a device for adaptation of digital input signals (DI) or output signals (DO) and which, per se, exhibits the functions selection between utilization of the device as binary input or output unit, selection of cable supervision, selection of current level warning, selection of current limiting level, selection of temperature level warning, selection of temperature protection and selection of voltage range. By access to the functions current limiting level and overtemperature protection, unlimited faulty connection under current and voltage conditions within the field of application may be allowed. All of the enumerated functions are accomodated within one and the same electronic unit, which is achieved by a far-reaching integration of the components used in few integrated circuits. The selection of function mode is obtained by a simple programming.

Abstract: An arc furnace (1) has an electrode (13) and connection members (14) for connection to a power-supply network (20) for supplying an arc (16) at the electrode with current. The furnace is provided with a voltage-pulse generating member (3) adapted, in connection with an interruption in the arc, to supply voltage pulses to the furnace for striking the arc.

Abstract: A device for high-pressure treatment, in particular of liquid substances which contain components with a consistency different from that of the liquid. The device comprises a cylinder member (1), two end members (2, 3), a high-pressure piston (4), two high-pressure seals (8, 9) and connection means comprising channels and valve members to conduct the substance to and from the cylinder member (1). When the substance is pressurized, the cylinder member (1), at least one of the end members (3), the high-pressure piston (4) and the two high-pressure seals (8, 9) delimit a high-pressure chamber (10). The connection means are arranged outside the high-pressure chamber and preferably in respective end members (2, 3).

Abstract: A compact gear with a gear housing (1) and an outgoing main shaft (4) which is rotatable in relation to the gear housing (1). The gear housing (1) supports a motor (2) with a drive shaft (3) projecting into the gear housing (1). On the drive shaft (3) there are arranged a first larger (6) and a second smaller conical toothed wheel (7). Transversely through the main shaft (4) extends a cross shaft (9) which is rotatably journalled in the main shaft (4). On opposite sides of this cross shaft (9) two equally large first (13) and second (14) crown wheels are rotatably arranged on the main shaft (4). The crown wheels (13, 14) engage, on opposite sides, with a third conical toothed wheel (12) arranged on the cross shaft (9). A third crown wheel (18) with a larger diameter than the second crown wheel (14) is rotatably arranged around the main shaft and secured to the second crown wheel (14).

Abstract: A magnetoelastic torque transducer for electrically measuring torsional stresses in a shaft (1) which is provided with at least one zone (6, 7) with an anisotropy the effect of which is to deflect the magnetic flux density in a direction away from the natural direction along the shaft and where the shaft is of a material which has a geometrically anisotropic microstructure with at least two phases, of which one phase consists of relatively soft-magnetic continuous streaks with magnetoelastic properties and at least one phase has a considerably lower permeability, the deflection of the magnetic flux density in the zone/zones being achieved by mechanically distorting the shaft within the zone/zones.

Abstract: A method and a device for determining the direction to a fault on a power transmission line in relation to a measuring station with the aid of phase currents and voltages, measured in the measuring station, by means of which change values .DELTA.U in the phase voltage, change values in the phase voltage .DELTA.UM of a line model and change values in the derivative .DELTA.I' of the phase current can be determined, and wherein for each measuring loop phase-ground the signal .DELTA.QL=(.DELTA.U-.DELTA.UM).multidot..DELTA.UI' is formed and if this value is smaller than a negative value assumed in advance, a fault lying ahead, in relation to the measuring station, has been detected, and wherein for each measuring loop phase-ground the signal .DELTA.QB =.DELTA.U.multidot..DELTA.UI' is formed and if this value is greater than a positive value assumed in advance, a fault lying behind, in relation to the measuring station, has been detected.

Abstract: A surge arrester with an elongated polymer housing (1) includes a stack of arrester elements (2), for example of zinc oxide. To limit the radial voltage stress which may arise in the polymer material upon pollution, the polymer housing (1) is provided on the outside with field-equalizing control electrodes (6) in the form of bands or rings of metal at regular distances along the arrester. The control electrodes (6) are electrically connected to the ZnO stack (2, 3) inside the housing (1).

Abstract: A method for manufacturing a rotor for an electric machine, for example, a permanent-magnet excited rotor for a high-speed a.c. machine, the rotor including an inner part constituting a rotor body and an outer part including a capsule tube which, when the rotor is completed, surrounds the rotor body with a shrinkage fit, includes fixing a first of the parts in a vertical direction in relation to a counter-support, and releasing the second part from a location above the first part so that it will fall within the fixed first part under the influence of gravity.

Abstract: A winding support body (6, 10) for transformers/reactors with a winding of a tape-formed superconductor (8), wherein the support body consists of a substantially straight, circular-cylindrical tubular body which, on the side where the winding is to be placed and out towards the two ends, is provided with a helical slot with a plane surface with a width equal to the width of the tape. In this way, each turn of the slot around the support body forms a surface which practically constitutes the envelope surface of a straight frustum of a cone. The angle (v) between a generatrix (9) of the envelope surface and the axial center line of the support body increases for each turn out towards the ends of the support body in such a way that the envelope surface at all points coincides with the direction of the magnetic field (FIG. 4 ).

Abstract: In a method for monitoring and/or control of a plant component (4A, 4B, 4C, 4D) connected to an electric power network (N1, N2), for example a tunable filter for harmonic filtering or a capacitor bank for generating reactive power in a converter plant for high-voltage direct current, products of, respectively, a voltage (U.sub.A, U.sub.B, U.sub.C, U.sub.D) occurring in the plant component and of a current (I.sub.A, I.sub.B, I.sub.C, I.sub.D, I.sub.AC) flowing therethrough are formed, and sine and cosine signals, the frequencies of which are equal to the product of the ordinal number of a selected tone and a fundamental frequency associated with the power network, the products are integrated and the phase difference (.phi..sub.un -.phi..sub.In) and/or the amplitude value (SUn, SIn, respectively) between/for the components of the voltage and the current of the selected tone are formed by quotient generation, multiplication, and summation of the integrated products.

Abstract: A cable assembly for an industrial robot comprising power and signal cables, which by means of watertight bushings extend through a watertight connection box connected at each motor unit, such that the respective table serves all the motor units connected along the cable. Within the respective connection box the cables are unsheathed, whereby a number of conductors for the motor unit in question are deflected whereas the other conductors, without joining, together with the remaining part of the deflected conductors are left to pass to the next motor unit.

Abstract: A high-voltage filter for filtering of harmonics in an electric power network comprises a first capacitive impedance element (C.sub.1) arranged in a first electric circuit (L.sub.1, C.sub.1) and a second (C.sub.2) capacitive impedance element arranged in a second electric circuit (L.sub.2, C.sub.2). The first and second electric circuits are inductively coupled to each other.

Abstract: A capacitor for temporary storage of electrical energy comprising at least two capacitor elements (2) composed of electrodes (5) which are separated by one or more dielectrics (6), and especially a power capacitor for high voltage. When the capacitor is being loaded, electrostatic forces give rise to mechanical forces between the electrodes in the capacitor. The forces give rise to vibrations which radiate as sound from the surface of the capacitor. Between, or adjacent to, packages (10) of compressed capacitor elements (2), there are placed one or more active or passive spring elements (11), which are adapted to change the natural frequencies of the capacitor. In this way, the oscillation resistance of the capacitor may be changed at the frequency ranges where the force is acting. The vibrations in the surface layer of the capacitor decrease, resulting in reduced sound radiation from the capacitor.

Abstract: A semiconductor light-emitting device employs a quantum well having a fundamental wavelength in the absence of an external electric field; a microcavity with two reflectors, having a resonance wavelength which closely corresponds to the fundamental wavelength of the quantum well; and electrodes for applying an electric field across the microcavity to change the wavelength of the quantum well and thereby control the radiance of the microcavity.