Abstract: An installation in a slitter mill for mounting a tool set (5), composed of annular tool parts (3), on a set-up device (1) provided with bars (2). The tool parts (3) are stored in a plurality of magazines (4) in a tool storage. A gantry robot (9) is adapted to collect tool parts (3) from the magazines (4) by means of a gripper (7) and to temporarily store the tool parts (3) in an associated intermediate magazine (13). The robot (9) with the intermediate magazine (13) moves between the magazines (4) and collects the desired tool parts (3) by means of the gripper (7) for loading a tool set in the intermediate magazine. A transfer device (15) is adapted to lift and transfer to the bars (2) a tool set present in the intermediate magazine (13). (FIG. 2 ).

Abstract: Protective equipment in a bipole converter station of an installation for power transmission by means of a high voltage direct current having main circuits on the dc side of the station. The main circuits have two separate pole parts, one part for each one of the two poles of the station, and a bipole part that is common to both poles. Measuring means in the station form measurement signals which correspond to operating quantities of the station. The measurement signals are supplied to the protective equipment. The protective equipment, dependent on the measurement signals and in their quarters with predetermined algorithm, takes measures to avoid permanent faults by influencing the operation of the station. The protective equipment has a pole protective means for each pole part and a bipole protective means for protection of the bipole part.

Abstract: A cooling device for cooling of current leads (6, 7) in the bushings of a cryotank (1), wherein the current leads in the gas-filled part of the cryotank are designed as plate-formed sub-leads (12) surrounded by a casing (8) of insulating material with an inner open part of rectangular shape. Between all the sub-leads inside the cryotank there are arranged a number of rows of inclined transverse ribs (13a, 13b, . . . 13n, 14a, 14b . . . 14n) of insulating material. On the inner walls of the casing, facing the plate edges of the sub-leads, and at the ends of the transverse ribs, shelves (15, 16) are fixed whereby spiral cooling coils are formed around the current leads from the lower edge of the casing.

Abstract: An installation for transmission of high-voltage direct current comprises a converter (SR1) which is controlled by a control unit (CU1). The control unit comprises a quotient-forming member, which forms a current order (IO) for the current (Id) in the dc connection of the installation in dependence on the quotient between a power order (PO) and a calculating value (UDF) of the direct voltage (Ud) at the converter, and a low-pass filter with a bandwidth (1/T1, 1/T2) capable of being controlled, which forms the calculating value as a filtered measured value (UD) of the direct voltage. The control unit comprises a signal-forming member which forms a state signal (FC), indicating that a short-circuit fault has occurred. The state signal influences the bandwidth of the low-pass filter such that the bandwidth is temporarily changed from a smaller value (1/T1) to a larger value (1/T2).

Abstract: An installation for transmission of electric power by means of high-voltage direct current has two converters (SRI, SRII), each of which is connected to an alternating-voltage network (NI, NII) and which are connected to each other through a dc connection (L). One converter (SRI) is controlled as a rectifier and another converter (SRII) is controlled as an inverter. One converter (SRI) is current-controlling and another converter (SRII) is voltage-controlling. The installation has means (VARC.sub.rect) adapted, at such a change of the control angle (.alpha..sub.rect) of the current-controlling converter (SRI) that the angle reaches a limit of a predetermined interval (.alpha..sub.max nom rect -.alpha..sub.min nom rect) to control, by means of the voltage-controlling converter (SRII), the direct voltage (Ud) of the transmission in such a way that said change is limited.

Abstract: Control equipment (CE1) generates an ordered value (AOL) of a control angle (.alpha.) in dependence on a limiting signal (AMINL, AMAXL), capable of being influenced, for a converter included in a series-compensated converter station. A calculating value (AFIRL) of a control angle is calculated continuously according to a predetermined relationship (H'1, H'2) which at least approximately imitates a relationship according to which, at a firing voltage (Ufir) for the valves of the converter equal to a preselected value (Uvref), said control angle is a function (G'0) of a current (Id1) and a voltage (Un1) in the converter station and the limiting signal is formed in dependence on the calculating value. (FIG.

Abstract: In a calibration method for an industrial robot (2-6), a calibration tool (8) supported by the robot hand (6) is brought into contact a spherical calibration body (7) with a known radius. Thereafter, the output signals from the position transducers of the robot axes are read and stored. This method is repeated a plurality of times with different robot configurations. Thereafter, the calibration parameters of the robot are calculated starting from the kinematic equations of the robot, a model of the relationship between axial position and position transducer signal, the known radius of the calibration body, and the read and stored position transducer signals.

Abstract: The invention relates to a method for supervising the functioning of a plurality of valve units, a system for performing the method, a control unit and a control assembly for cooperation with the control unit. Each valve unit in the system comprises a semiconductor element (THY1-THYN) and a control unit for controlling the semiconductor element. The control unit comprises a trigger order input for receiving a trigger order (FP), an indication output for emitting a first indication signal (TP) and a trigger signal output (100) for emitting a trigger signal to the semiconductor element. The method comprises the steps: detecting a positive forward voltage (U.sub.T) across the semiconductor valve, generating a first indication signal (IP) when the forward voltage (U.sub.T) exceeds a first threshold value (U.sub.1), generating a trigger signal upon detected receival of the triggering order signal (FP), and the step: generating a second indication signal (SSTP) when the forward voltage (U.sub.

Abstract: Apparatus for damping oscillations at or near a natural resonant frequency in a power transmission system, in which an oscillator emits a reference signal oscillating at the natural resonant frequency; a multiplication circuit for multiplying an operating signal corresponding to the prevailing operating condition of the HVDC-system with the reference signal; a memory and a clock-pulse generator for serially sampling the output signal from the multiplication circuit by clock-pulses; the memory has the capacity to store sampling values up to a number which at least corresponds to the period of the reference signal; a summation circuit which, via a parallel output from the memory, for summing a number of the latest sampling values which corresponds to at least one period of the reference signal; a diagnostic and determination circuit provided with the output signal from the summation circuit, in which circuit the size, sign, variability and presence of an output signal from the summation circuit is tested accord

Abstract: Filter equipment is adapted for connection to an ac power network (N) for damping of current harmonics originating from an installation (TR, SR1, SR2), connected to the network, for power transmission by means of high-voltage direct current. The equipment has a three-phase filter set (F) with three filter branches which are each normally connected to a separate phase of the network via first switching members (BO). A spare filter branch (FR) is arranged as a stand-by for the three filter branches of the filter set (F) and is adapted for connection to an optional phase of the network by means of second switching members (BR).

Abstract: A series-compensated converter station in an installation for transmission of high-voltage direct current is connected to an alternating-voltage network (N) with three phases (A, B, C, respectively). The converter station comprises at least two direct-voltage series-connected six-pulse converter bridges (SR1, SR2, respectively), a three-phase transformer coupling with two secondary windings (SW1, SW2, respectively), and a star-connected primary winding (PW) with a neutral point (NP) connected to ground as well as a series capacitor unit (CN) for each one of the three phases. Each one of the converter bridges is connected to a respective secondary winding and the primary winding is connected to the alternating-voltage network via the series-capacitor units. The transformer coupling exhibits a high impedance to zero-sequence currents through the primary winding of the transformer coupling.

Abstract: A device for continuously manufacturing a cast strand by continuous casting of liquid metal melt wherein the flow of the liquid metal in the non-solidified portions of the strand is controlled by means of a static or periodic low-frequency magnetic field. A mould adapted to be supplied with the melt includes copper plates (2a,2b) which form a casting mould space with a rectangular cross section, water box beams (3) which are arranged outside the copper plates to support and cool them, and a member (4) holding the mould together. Magnetic field-generating devices, i.e., magnets, are provided close to the mould to generate a static or periodic low-frequency magnetic field which acts in the path of the inflowing melt and divides the primary flow as well as checks any secondary flows arising. Each magnet comprises a front core (5), a rear core and a coil (7).

Abstract: A method and device for high-pressure treatment of liquid substances, for example foodstuffs. The substance undergoes a cyclic process whereby a limited amount of the substance during each cycle is pressurized in a pressure intensifier (1) to a predetermined pressure and is then maintained at this pressure for a predetermined period of time. After the substance has been pressurized in the pressure intensifier (1), it is conducted to a pressure chamber (10) while maintaining the predetermined pressure. The substance is further caused to reside in the pressure chamber (10) for the predetermined period of time by being caused to pass over a predetermined distance between an inlet (9a) and an outlet (9b), which are arranged in the pressure chamber (10).

Abstract: Control equipment (CE2) generates an ordered value (AOL) of a control angle (.alpha.) in dependence on a limiting signal (AMAXL), capable of being influenced, for a converter included in a series-compensated converter station. A calculating value (AMARG) of a control angle is calculated continuously according to a predetermined relationship (M0, M1, M2, M3) which at least approximately resembles a relationship according to which, at a commutating margin (.gamma..sub.m) equal to a preselected value (.gamma..sub.p), said control angle is a function (F0) of a current (Id2) and a voltage (Un2) in the converter station and the limiting signal is formed in dependence on the calculating value.

Abstract: A magnetoelastic torque transducer for measuring, in a non-contacting manner, the torque in a stationary or a rotating shaft. The transducer comprises a shaft (1) with surrounding excitation windings (2, 3) and measuring windings (10, 11). Concentrically with the windings, anisotropic measuring zones are created by applying layers (8, 9), for example in the form of copper strips, on the surface of the shaft. The angle between the strips and a generatrix to the cylinder surface of the transducer shaft is in a preferred embodiment chosen to be .+-.45.degree. (FIG. 5).

Abstract: A converter connection for conversion between alternating voltage and direct voltage, for connection to a power network (DCN) having a neutral pole (P0) and at least one pole (P+,P-) energized by direct voltage in relation to the neutral pole, comprises a voltage-source converter (VC) with two direct-voltage terminals (DP, DM). At least one of the direct-voltage terminals of the converter is connected by means of an electric pole conductor (W1, W12, W11, W21, W2) to at least one of the poles of the power network which are energized by direct voltage.

Abstract: A power transmission system for high-voltage direct current comprises a rectifier station (1) and an inverter station (2), which are interconnected by a dc connection (4), as well as a third converter station (3) connected between the dc connection and an ac network (3c). The third converter station comprises a converter (3a) connected to the dc connection via a direct-voltage converter (5). The direct-voltage converter comprises at least a first and a second converter stage (8:1, 8:2), each with a positive terminal (TP:1, TP:2), a negative terminal (TM:1, TM:2) and an output terminal (TO:1, TO:2) and comprising a voltage-source converter circuit (V, C1, SL) with at least one extinguishable semiconductor valve (T1, T2). The positive terminal of the second converter stage is connected to the output terminal of the first converter stage and the output terminal of the second converter stage is connected to the negative terminal of the first converter stage.

Abstract: A series-compensated converter station included in an installation for transmission of high-voltage direct current comprises a converter (SR1, SR2) with at least one 6-pulse bridge (BR). Via series capacitors (SCR, SCS, SCT) the 6-pulse bridge is connected to a three-phase alternating-voltage network (N1, N2) with a fundamental frequency (f.sub.01, f.sub.02). Control equipment (CE1, CE2) generates an ordered value (AOL) of a control angle (.alpha.) for valves (V1-V6) included in the 6-pulse bridge in dependence on a limiting signal (AMAXL) capable of being influenced. An amplitude signal (AMPL) is formed which corresponds to the amplitude (C.sub.1) for a component (C.sub.1 cos(2.pi.f.sub.0 t+.phi..sub.1)) of the fundamental frequency in the direct voltage (Udb) of the 6-pulse bridge and a compensating signal (ACOMP) is continuously calculated in dependence on a sensed voltage (Un1, Un2) at the converter station and on the amplitude signal.

Abstract: The invention relates to an industrial robot with two lower robot arms directed upwards from a fixed robot stand, the robot arms at their lower end being pivotably journalled in the stand around horizontal axes and at their upper end being pivotably interconnected by a yoke in such a way that a four-bar linkage is formed. The linkage is provided with a first driving unit. An upper robot arm is journalled around a fifth axis in a fixing member which is supported by the yoke and which is rotatably journalled around a sixth axis. The upper robot arm and its fixing member are provided with a second and a third driving unit, respectively.

Abstract: A high-pressure press is provided with a high-pressure chamber and an end member located at one end of the high-pressure chamber which serves as a packing holder. The end member is provided with a support surface which, under maximum pressure condition in the high-pressure chamber, faces an opposite end surface on the low-pressure cylinder which serves as a stationary part of the press. In this way, forces acting in a direction from the high-pressure chamber are transmitted to the stationary part when the support surface on the end member is brought into contact with the supporting end surface on the low-pressure cylinder.