Abstract: The switching system, preferably suitable for distributing electric energies of medium-high voltage, includes a metal housing which is filled with insulating gas and in which at least one circuit breaker, one isolating switch, one earthing or grounding system and one busbar are arranged. In this arrangement, the contact arrangement of the circuit breaker is located in a housing which is accessible from the outside without intervention in a busbar housing which contains the busbar. This system saves parts and has a small space requirement while its components subject to the most wear are easy to maintain. This is achieved by the fact that the contact arrangement of the isolating switch is provided in the busbar housing and that the housing of the circuit breaker is provided with a housing part of insulating material which penetrates the wall of the busbar housing as a gas-tight current lead-through.

Abstract: In the rotor blade ring of an axial flow turbomachine, the rotor blades are each provided at their radially outer ends with a shroud plate and are fastened at their radially inner ends, by means of a root, in a corresponding groove of the machine rotor. The shroud plates are connected together in the peripheral direction by means of wires rolled into turned recesses. Grooves (10), with a clear width (w.sub.1) which is dimensioned larger than the width (w.sub.2) of the shroud plate turned recess (8) provided for the wire (7) to be rolled in, are machined in the end surface (6) of the shroud plate (2). A spacer means (11), surrounding the wire at least in the region of the rolling positions and removable after rolling, is laid in the grooves during the rolling procedure. This material is preferably a hard paper which is burnt to ashes during machine operation.

Abstract: A liquid crystal display based on the bistability effect, wherein the distance between the support plates is smaller than 10 .mu.m and the total twist of the liquid crystal is between 180.degree. and 360.degree., preferably about 270.degree.. Over the entire viewing area of the display, randomly distributed spacers are provided. Because of these measures, the range of the bistable action is so narrowed that the display can be driven with operating voltages outside this range, using conventional multiplexing techniques. A high degree of multiplexing with short switching times and excellent contrast is obtained. The range of viewing angles is very large and independent of the direction of illumination.

Abstract: Rotary flows are generated in a variety of technical installations.In these uses, the particular properties of the rotary flows generated and consequently those of the swirl generator itself play an essential part. Thus, for example in burner construction, a swirl is imparted to the combustion air, in order, on the one hand, to accelerate mixing between the fuel and air and, on the other hand, to utilize a possible return flow to improve the ignition condition.One question, among others relating to the design of the swirl generator, is to decide which flames with which properties are produced by the burner.It is therefore desirable, for control and optimization of the flame properties, to have available a swirl body of variable swirl intensity and swirl distribution.For this purpose, the swirl body (1) is equipped with several exchangeable guide blades (4) which are pushed in through a slotted outer tube (2) radially and at a pitch angle (.theta.).

Abstract: A synchronous machine with alternating-current exciter, wherein the stator of the exciter machine, the rotor of which runs in the opposite direction of rotation to that of the stator field, is fed from a three-phase power controller. The voltages induced in the rotor of the alternating-current machine are rectified by diodes in a three-phase star circuit. In order to minimize the effect of the voltage peaks originating from the hole-storage effect during the commutation of the diodes, which peaks are abnormally high as a result of the mutual interaction of the harmonics, there is produced a parallel path for high-frequency currents in the form of a protection circuit having low-pass characteristic so that the mutual interaction between stator and rotor harmonics if greatly reduced. Because of the risk of self-excitation, the elements of the protection circuit are matched to the machine and cause as few additional losses as possible.

Abstract: In an internally cooled tubular ozonizer, there is built into the interior of the glass tube (5) a cooling tube (9) whose outer diameter is only slightly smaller than the inner diameter of the glass tube (5). The annular gap left is filled up with a temperature-resistant casting compound (10) which conducts heat well. In the case of a synthetic resin casting compound (10), the cooling tube (9) is connected galvanically via contact springs (11) to the metal layer (8), serving as the inner electrode, on the inner wall of the glass tube (5). The heat transfer from the cooling agent in the cooling tube (8) to the glass tube (5) is not impeded by the casting compound (10). Temperature stresses between the glass tube (5) and the cooling tube (9) are largely reduced, as a result of which the operational safety of the ozonizer is increased, especially at fairly high power densities.

Abstract: In modern ozone generators, high power densities are achievable when dielectrics (3) based on ceramics or filled plastic dielectrics and corresponding gap widths and dual cooling are used. With respect to efficiency, such ozone generators are inferior to those with a glass dielectric.To improve the efficiency and the resistance to the discharge attack, it is proposed to glaze the titanium oxide ceramic on the surface and to coat the plastic dielectrics with a high-temperature ceramic adhesive based on SiO.sub.2.

Abstract: A cast housing is provided for carrying switchgear components, such as a power switch or circuit-breaker, a busbar, a disconnecting switch and a grounding switch and bushings, to a multi-phase medium-voltage switchgear. It is substantially cuboid-shaped and is filled with an insulating gas. This cast housing is designed such that it may be used without substantial modifications in all possible designs of switchgear for a given switchgear voltage. This is achieved by the cast housing having large openings at the front wall and at the side surfaces adjoining the front wall and having a comparatively small opening at each of the rear walls and the top and bottom surfaces for each phase of a switchgear having from one to four phases.

Abstract: Where different 3-phase systems are connected to each other via two static converters having an intermediate direct-current circuit, the exchange of power via the intermediate direct-current circuit can be interrupted by a severe disturbance, for example by failure of a static-converter or by line or busbar faults causing a short-circuiting of one of the static converters. This interruption means a change in the balance of effective power and, associated with this, a shedding of reactive load for the other undisturbed 3-phase system. To reduce high dynamic overvoltages which can lead to plant components being endangered or to operational disturbances, the firing angle of the static converter remaining in operation is regulated with dependence on the alternating voltage of the alternating-current system connected to this static converter, in such a manner that the overvoltage is reduced. This is carried out by regulating the current.

Abstract: The high-voltage direct-voltage source is composed of a bank of high-voltage capacitors and a charging circuit for charging the capacitors. A monitoring unit is connected in parallel with at least one of the high-voltage capacitors. After a predetermined limit value of the charging voltage has been exceeded, this monitoring unit emits a signal to a control device of the charging circuit preventing the further charging of the bank. The input of the monitoring unit is formed by a resistive voltage divider comprising a high-voltage-side and a low-voltage-side resistor.A high-voltage direct-voltage source is to be created in which a dielectric overloading of the high-voltage capacitors can be avoided in a simple manner which is insensitive to electric disturbances. This is achieved by the fact that the high-voltage-side resistor of the resistive voltage divider consists at least partially of non-linear voltage-dependent resistance material.

Abstract: The gas turbine of an air storage gas turbine power station is so designed that it can provide the nominal output requirement without extracting air from the storage cavern (17). The compressor group (3+4) has internal control organs in the form of guide vanes and possibly also rotor blading which can be adjusted during operation. This adjustable blading makes it possible to maintain the pressure ratio necessary for attaining the nominal power during the other operating conditions also and makes it possible to keep the compressor final pressure at at least the same level as the storage air pressure. By this means, it is possible to fill the storage cavern (17) during the whole of the part-load range and during idling operation in addition to filling it by exclusively electric motor drive of the compressor group (3+4) by the generator (2 or 31), connected as motor, or by an electric motor (29) specially provided for this purpose.

Abstract: An overvoltage arrester having power connectors at its opposite ends is provided with an insulating housing that encloses a stack of coaxially arranged cylindrical varistors at least partially embedded in insulating material. An annular space is provided between the insulating material and the interior wall of the housing and is filled with an electrically insulating, heat-conducting material. The housing is protected from bursting in the event of the occurrence of an electrical flash-over along the varistor stack by a pressure relief duct that extends along the varistors between the power connections.

Abstract: A gas-blast switch preferably suitable for the switching of medium voltage has two switch pieces interacting in an insulating gas filled housing. A fixed switch piece is provided with a hollow space which is connected via channels to a pressure reservoir coaxially encircling the switch pieces. The pressure reservoir during switching-off, can be connected to an arc chamber terminated at least partially on its outer side by an insulating body.In this switch, a build up of pressure which is adequate to quench the arc is to be achieved at low currents by simple means and an excessive build up of pressure at high currents is to be avoided.This is achieved when the insulating body is made as an insulating nozzle and has a gas inlet, which can be connected to the pressure reservoir, and a gas outlet which is located between a narrow point of the insulating nozzle and the free end of the fixed switch piece.

Abstract: A pressure exchanger, preferably usable as a high-pressure compressor for gas turbine installations, has a multiplicity of coaxial cell rotors which can be driven in the same direction, and a central pressure exchanger combustion chamber located within the innermost cell rotor. Driving gases generated in the combustion chamber flow through the cell rotors in series from inside to outside and can be expanded as low pressure driving gases in the low pressure part of the turbine. The air to be compressed flows through the cell rotors in series from the outermost cell rotor towards the inside. A part of the air mass flow compressed to the final pressure, which part is greater than the driving gas mass flow, arrives as combustion air in the pressure exchanger combustion chamber; the other part of the air can be used as combustion air for a turbine combustion chamber, which generates high pressure driving gas for the gas turbine.

Abstract: A method for attenuating at least one unwanted harmonic, particularly the second harmonic, with respect to the system frequency in a multi-phase alternating current system, wherein an additional stabilizing circuit is installed into a conventional current/voltage controller including a current/voltage controller and a three-phase firing pulse generator in a reactive-power compensator connected via a reactive-power transformer and a current transformer to a 50 Hz three-phase system. The reactive power compensator has for each phase of the three-phase current at least one air choke, which is connected via a current transformer and via an alternating-current switch via another sum-current transformer to a secondary winding of the reactive-power transformer. In addition, the reactive-power compensator has for each phase of the three-phase current at least one capacitor bank or a capacitor, which is connected via a current transformer and an alternating-current switch (13) to the sum-current transformer (20).

Abstract: The gas-blast circuit breaker preferably provided for switching medium voltage has a housing (1) filled with insulating gas. In this housing (1), two contact members (7, 8) are arranged which can be moved relative to each other along an axis (6), and a fixed (8) one of which is formed of two half-shells (11, 12) spaced apart from each other along a plane of separation (16). A power terminal (5), arranged transversely to the axis (6), is electrically conductively connected to the fixed contact member (8). This circuit breaker is to be simplified while retaining a reliable current transfer from the power terminal (5) to the fixed contact member (8).

Abstract: Two component workpieces (1, 3) consisting of different superalloys or of the same superalloy are bonded together to form a monolithic whole, with the insertion of a layer 1-2 mm thick consisting of a powder (4) of composition similar to or identical to that of the component workpieces (1, 3), by hot pressing in accordance with the diffusion bonding process. The workpiece surfaces to be bonded do not have to have narrow tolerances, but are with advantage provided with grooves (5). The groove depth (s) may be 0.25 mm. Pressing temperature =950.degree.-1,000.degree. C., deformation velocity .epsilon.=1-5.10.sup.-1 s.sup.-1, degree of deformation .epsilon.=0.1-0.02. The process is suitable for the bonding together of component workpieces (1) consisting of a dispersion-hardened, nickel-based superalloy or of component workpieces (1) of such an alloy and workpieces (3) consisting of a cast conventional superalloy.

Abstract: The gas-blast circuit breaker, which is preferably provided for switching medium-high voltages, has two arcing and two rated-current contacts each of which are located in a housing filled with insulating gas and operate in conjunction with each other. For purposes of a compact construction, electric connections, are carried into the interior of the housing transversely to the direction of movement of one moving contact of the two arcing contacts. The driving energy required for a switching process is intended to be kept as low as possible while retaining the compact construction. This is achieved by the fact that the moving rated-current contact is rotatably supported and that a drive, acting on the moving arcing and the moving rated-current contact has two rods which are pivoted at a driving crank, one of which rods is pivoted at the moving arcing contact and the other one of which is pivoted at the moving rated-current contact.

Abstract: The present invention relates to a protective device for a load connected to a power supply line of an electric power system, comprising an LC network having low-pass characteristics, connected into the power supply line on the system side preceding the load. So that disturbances with frequencies below the cut-off frequency of the LC network can also be kept away from the load, a switching element controlled by a monitoring device is arranged according to the invention in series with the LC network in the power supply line. The monitoring device is connected to the power supply line on the system side at a junction preceding the switching element and keeps the switching element closed only for as long as the instantaneous value of the time derivation of the voltage on the power supply line deviates from the instantaneous value of a nominal value which is predeterminable in its variation with time, by no more than an equally predeterminable amount.

Abstract: Monitoring of trigger circuits of power switches of electrical power supply devices which can experience faults due to breakage of conductors, oxidation of contacts, loosened terminal contacts, short circuits in trigger coils, etc. In order to improve fault monitoring, oscillator oscillations are applied to the trigger circuit of a power switch and are monitored. A fault- or alarm signal is generated in response to a detuning of an oscillator when the detuning persists for a predetermined time. The inductance of the circuit-breaking coil of the power switch serves as a frequency-determining element of the oscillator. A lag element with a delay of 500 ms is inserted after the oscillator. If the oscillator stays detuned for more than 500 ms, a Schmitt trigger is triggered by the lag element, whereby an alarm relay is actuated which switches on an alarm device via an alarm relay contact.