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Power conversion system comprises a power converter, using multiple branches to convert inlet electric power and discharge capacities into multiple phases. Each branch comprises upper and lower arms; a controller 30 that controls the upper and lower arm of each branch, in order to control pulse current passing via the branch. The controller 30 calculates a command of duration of connection for each branch in one period of control for each phase and for the first and second branches from multiple branches, provided for one determined phase, changes the phase of the calculated command of connection duration, so that the time period, when the positive pulse current flows via the first branch, and the time period, when the negative pulse current flows through the second branch, cover each other in one control period. |
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Aircraft power supply circuit comprising asynchronous machine Power supply circuit for supply of electric energy in an aircraft comprises a power supply generator made as capable of rotation by means of an aircraft motor, for supply of power electric equipment of an aircraft motor. At the same time the power supply generator comprises an asynchronous machine connected with an excitation device. The asynchronous machine comprises a rotor, made as capable of rotation by means of a motor, and a stator connected with the specified electric equipment. The excitation device is made as capable to cause passage of reactive current in the specified stator. |
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Device for realisation of cyclic movements Device comprises a setting unit, three summators, a sensor of output coordinate of a regulation object, delay units, a filter and additional delay units, connected to each other, as specified in the invention. All delay units are made with parameters determined in accordance with time coordinates of points of transition characteristic of the regulation object, and the delay time of the first delay unit also depends on the cycle time. |
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By a signal from current sensors, a failure is detected in a chain of one of three phases of an anchor winding. Then by means of a microcontroller device a signal is sent for actuation of a protective element of the failed phase, the process of automatic switching of two operating phases is carried out, providing for development of a motor torque. The protective element is represented by power switches of that inverter stand, to which the failed phase is connected. Remaining switches, forming a single-phase bridge inverter, are switched by means of a microcontroller device, carrying out serial selection of previously recorded control codes from memory cells corresponding to the condition of the anchor winding and position of the rotor. The criterion of available fault, as well as sound and light signals announcing the available fault and time of its occurrence, are generated by means of the microcontroller. |
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Device to control and ensure durability of double-fed motor Device to control and ensure durability of a double-fed motor comprises an induction motor, a frequency converter made of a controlled rectifier and an inverter, a three-phase transformer. The rectifier is made as a grid thyristor converter, and the inverter - as a rotor thyristor converter arranged in accordance with a bridge three-phase circuit. The device additionally comprises current sensors, protective elements, two reserve half-bridges, each comprising three symistors and two reserve thyristors, and a microcontroller, which is connected to all thyristors and symistors. The specified elements are connected as specified in application materials. |
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Method and system for turbomachine slow barring Invention relates to turbomachine shafting slow barring. Proposed system comprises electrical generator, primary exciter and secondary exciter. In rated mode, auxiliary exciter is used as a permanently-excited synchronous machine for electric power generation. In slow barring mode, secondary exciter doubles as a slow barring motor. Note here that this system comprises the switch to selected rated mode and slow barring mode. |
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Vector control device of asynchronous motor speed Proposed device includes a calculation unit that calculates speed and flux linkage parameters under conditions of insignificant variation of external moment Mc. This allows maintaining maximum and constant motor efficiency within the whole allowable range of variation of external moment at the specified angular speed without using any speed sensor mechanically connected to the motor shaft and a unit of sensors of the main flux linkage, which are arranged in the gap of the stator. |
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Device for failure detection in step electric drive Invention refers to electric engineering and can be applied in systems with electric step drive based on three-phase, four-phase and six-phase step drives. Effect is extension of functional capabilities due to enabled switching and halt modes for motors with different number of phase windings, step motor operating in alternate cycling mode controlled by switching mode selection buses, and due to automatic failure detection during step motor operation by comparing codes of actual motor power supply, generated by known limit sensors of phase current and voltage with reference codes of backup data channel. In addition, failure detection device for electric step drive features second joint data output of reference switching combinations, digital comparator, new functional links listed in materials of the application. |
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Device for failure detection in step electric drive Invention refers to electric engineering and can be used in systems with step electric drive based on motors with different phase number, operating in reverse alternating and paired switching mode, live and dead standby, with automatic determination of routine operation mode and single and multiple failures due to hardware implementation of modified Hamming algorithm. Failure detection device includes first-fourth convolution schemes, buses of phase current and voltage limit sensors, additional digits of permanent memory corresponding to reference digits of Hamming code, OR circuit, decoder and indication unit, and new functional links listed in application materials. |
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Electric drive of a roll mill includes angular velocity setter (1) of independent-excitation DC motor (13), scaling amplifier (2), two comparator elements (3, 4), two nonlinear functional converters (5, 6) performing functions listed in the invention, controller switch element (7), limiting unit (8), speed and current controllers (9, 10), power amplifier (11), current and voltage sensors (12, 14), motor angular velocity and rolling speed sensors (15, 16); result is achieved by damping of oscillation caused by nonlinear dependency of rolling momentum from angular velocity of electric drive, and operating point shift in the electric drive to stable operation zone, which is performed by connection of constant signal U0 to input signal of current controller at critical angular velocity of motor rotation when oscillation evolves, in order to ensure controlled speed change and respective shift of operating point to stable zone. |
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System of synchronous generator excitation with controlled external boosting In excitation system of synchronous generator, external DC source (11) is connected parallel to inductor (3) via common electronic switch (12). Current converter (13) is connected in series with armature winding (2) and connected to bypass (14) and second rectifier (15). Excitation system includes analogue to digital converter (16), two storage registers (17, 18), pulse distributor (19), stable frequency pulse generator (20), substractor (21), reference register (22), numeric comparator (23), two differentiators (24, 26), RS trigger (25), logic OR element (27), START bus (28), limiting generator (29), inverter (30), logic AND element (31), resistors from first 32-1 to Nth 32-N and section electronic switches from first 33-1 to Nth 33-N. Resistance Ri of resistor 32-i is determined by formula Ri=R1/2(i-1) where R1 is resistance of resistor 32-1. |
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Control over inverter-fed three-phase motor Invention relates to controlled motors, particularly, to inverter-fed motors and can be used in AC controlled drives. Proposed method comprises conversion of setting voltage in coordinate transducer into phase control setting voltages as angle signal from motor rotor turn transducer. Besides it includes conversion of phase control setting voltages in three-phase self-contained voltage inverter with PWM at input and synchronous motor stator three-phase supply voltage. Control phase setting voltages are generated in coordinate transducer in compliance with selected algorithm. |
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Dynamic torque control method for engine flywheel Invention is related to the field of electric engineering and may be used in spacecraft angular position control systems for the orbital coordinate system. In the dynamic torque control method for the engine flywheel based on a precision frequency-phase system of speed regulation for a brushless DC motor the reference digital model of the engine flywheel is used as the source of the preset phase and frequency and the second auxiliary circuit that performs function of initial synchronisation for the model integrators with actual output coordinates of the engine. Switching from the main circuit to the auxiliary one and back is made by the circuit switch against signals at the output of a frequency-phase discriminator. The circuit switch allows functioning of the device in a control mode both for an electromagnetic and dynamic torque. Current of the engine is generated on the basis of a dynamic torque control signal and a phase mismatch signal between the output signals for the reference digital model and signals of the rotor position sensor. |
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High-voltage three-phase alternating current generating system Invention in the field of electrical engineering. The system contains a synchronous generator with excitation from permanent magnets and three galvanically isolated three-phase windings at the stator, a static converter of electric energy based on direct frequency converter with three-phase output and natural commutation (a cycloconverter), which each phase is assembled as per the scheme of three-phase bridging reverse rectifier (BRR) with a capacitor of a low-frequency filter coupled in parallel to its output terminals and powered by one of the three-phase systems of the synchronous generator windings, one of the BRR outputs is coupled to the respective phase of a three-phase load. There is an additional phase of the direct frequency converter with three-phase output and natural commutation, which is assembled as per the scheme of three-phase bridging reverse rectifier with a capacitor of a low-frequency filter and powered from a three-phase transformer, which primary windings are coupled to any three-phase system of the synchronous generator windings, the second outputs of the three BRRs are coupled to one output of the additional phase of the direct frequency converter while the second output of the additional phase of the direct frequency converter is coupled to the zero wire of loads in the generating system. |
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Submersible pumpset control station Invention is related to oil-production equipment and namely to control stations for electrocentrifugal pump engines, and it may be used for formation fluid production by means of pumps. The pumpset control station includes a cabinet consisting of the first and second spaces and two additional spaces. Placement of fans used for circulation of the cooling air in the second additional space allowed combining a hydraulic part of the inverter and rectifier cooling systems and the second space in the cabinet with reactive elements of the submersible pumpset control station. Besides, the suggested engineering solution allows use of the second additional space for installation of elements of the control station which require additional cooling. Temperature sensors of the reactive elements cooling systems are installed at the surface of these reactive elements. |
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Invention suggests a digital electric drive containing a setting device which output is connected to a position regulator with its output connected to a variable-speed control unit, a pulse-width modulator, a servomotor, at that the servomotor is made as a disc toothless thyratron motor divided into three segments and each segment is coupled to an individual power amplifier and a phase current sensor for each segment, which are coupled to a torque valuator, output of the latter is connected to a torque controller, which second input is connected to the output of the variable-speed control unit and output is connected to the pulse-width modulator, the output of the modulator is coupled to three power amplifiers of the motor segments, the electric drive is equipped additionally with a position sensor, which input is connected to the motor and output to the position sensor controller, the output of the controller is connected to the second input of the position regulator and to the second input of the variable-speed control unit through a velocity valuator. |
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Power distribution system and method Invention is related to a power distribution system and method. The system (10) contains a lot of generating systems (12, 14, 16, 18), at that each generating system (12, 14, 16, 18) contains an alternating current generator (20, 22, 24, 26) coupled directly to the rectifier (28, 30, 32, 34). The alternating current generator (20, 22, 24, 26) with slewing capacity is coupled to the energy source (13, 15, 17, 19). During operation of the energy source (13, 15, 17, 19) the alternating current generator (20, 22, 24, 26) generates an output signal (38, 40, 42, 44) desynchronised in regard to the variety of other generating systems (12, 14, 16, 18) and having a variable velocity. The rectifier (28, 30, 32, 34) coupled directly to the generator (20, 22, 24, 26) is adapted to convert an output signal (38, 40, 42, 44) of the alternating current generator (20, 22, 24, 26) into direct current output signal (46, 48, 50, 52). The direct current distribution bus (36) is connected to direct-current outputs (46, 48, 50, 52) of each rectifier (28, 30, 32, 34). The system (10) contains also a variety of inverters (56, 58, 60, 62) adapted to receive power from the bus (36). The output signal of each inverter (56, 58, 60, 62) is adapted to activate an alternating current motor (64, 66, 68, 70). |
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Power conversion device consists of the following components: switching elements (S1-S6) which are connected in parallel to the common current-conducting bus and excite currents with different phases; and a controller (14) of the electric motor which controls the respective switching elements (S1-S6). The controller (14) of the electric motor controls the respective switching elements (S1-S6) so that the direction of current fluctuation stipulated by switching on/off of one switching element is opposite to the direction of current fluctuation stipulated by switching on/off of at least one of other switching elements. |
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Device for stepped motor control Invention relates to ACS and can be used in systems with discrete drives built around three-phase, four-phase and six-phase steeped motors. Claimed device implements Hamming coding algorithm by hardware means to reveal and indicate the address of single fault. For this, proposed device incorporates 1st, 2nd and 3rd convolves, reference check discharge buses, indicator, power amplifier unit with current and voltages tranducers for every phase. |
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Device for stepped motor control Invention relates to ACS and can be used in programmable discrete drive motor. Claimed device comprises the main four cycle reversible pulse distributor for control over stepped motor including two-digit reversible binary counter. Clock, permit and count direction inputs of the latter are connected to appropriate clock pulse, control and reverse buses. The latter are group inputs of said distributor. Besides, it comprises two inverters and XOR elements. Note here that additionally this device incorporates 1st and 2nd standby distributors, unit of majority gates, 1st and 2nd sets of XOR of fault address detection unit. First outputs of the main and standby distributors are connected to 1st…3rd inputs of 1st majority gate. Second outputs of the main and standby distributors are connected to 1st…3rd inputs of 2nd majority gate. Third distributor outputs are connected to 1st…3rd inputs of 3rd majority gate. Third distributor outputs are connected to 1st…3rd inputs of 3rd majority gate. Outputs of majority gates are connected via power amplifiers to windings of stepped motor to make the 1st group output of the device. 1st and 2nd output of fault address detection unit group are connected to 1st…3rd outputs of the main and standby distributors. |
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Synchronous motor start-up method Invention is related to the sphere of electric equipment and may be used for production of asynchronous motors with low starting current. Technical result is attained due to the connection diagram and increase in inductive reactance of the stator winding at wye-connection of phases. The method of synchronous motor start-up is suggested by means of switching of a three-phase stator winding in the course of which, according to the invention, two standard coil groups, from the first up to the sixth one, are included into phases of the bipolar winding, two pairs of coil groups, from the first up to the sixth one, are included into phases of the four-pole winding, three triples of coil groups, from the first up to the sixth one, are included into phases of the six-pole winding, at that the phase band width is changed from 120 electrical degrees to 60 electrical degrees by switching the winding from the delta-connection to the wye-wye-connection with formation of neutral point from the delta-connection middle without changes in a number of poles and breakage of phase winding connections. |
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Direct current drive with elastic couplings Invention is related to the sphere of electric engineering and may be used in the control system for electric drives. The electric drive contains a rate setting unit, a speed control unit, a closed current control circuit with armature current sensor, electromechanical equipment of the motor, an actuator with elastic couplings and an actuator shaft speed sensor, an elastic torque sensor and a steady load sensor connected in-series. The speed control unit includes a differentiating element, seven scaling elements, a summing member and a zero-order interpolator. The first scaling element is connected to the rate-setting unit; the second scaling element is connected to the differentiating element; the third scaling element is connected to the input of the steady load sensor; the fourth scaling element is connected to the output of the armature current sensor which input is connected to the output of the closed current control circuit. The fifth scaling element is connected to the output of the motor shaft speed sensor; the sixth scaling element is connected to the output of the elastic torque sensor and the seventh scaling element is connected to the output of the actuator shaft speed sensor. The scaling elements are connected to inputs of the summing element. |
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Multiple-motor electric carrier and method of its control (versions) Set of invention relates to automotive industry. Proposed carrier comprises power regenerator, motion speed and moment setter, braking moment setter, motion mode selector, motors, inverter, top level control system (TLCS), consumed current transducers of inverters and load distribution system (LDS). LDS outputs are connected to outputs of inverters and current transducers. Signals of setting the factors of load distribution between drive wheels are fed to LDS inputs. LDS outputs are connected to inputs of inverter speed setting. In compliance with first version, control method consists in determination of load mean current and drive actual current departure magnitude, generation of speed setting correction signal to set required distribution of torques at drive wheels via communication link proceeding from obtained drive current departure magnitude. In compliance with second version, control method consists in determination of load mean current and drive actual current departure magnitude, generation of speed setting correction signal to set required distribution of torques at drive wheels via communication link proceeding from obtained drive current departure magnitude. |
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Method for control of asynchronous motor In the control method implemented in accordance with patent claim a preset frequency setting is stopped at change of input alternating voltage within wide range or change in the preset frequency setting; when current or voltage in a direct-current link reaches its critical values the inverter is switched off from the direct-current link till current or voltage in the direct-current link drops below the critical value. In case of change in frequency setting, start-up or shutdown of an asynchronous motor output voltage and frequency are changed according to the same law of scalar variable-frequency control. At inverter cut-off output voltage and frequency are reduced smoothly up to zero value and at restart the asynchronous motor is accelerated smoothly with current values of voltage and frequency in order to exclude generator mode at frequency drift. |
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Alternating current electric drive Alternating current electric drive contains asynchronous motor, inverter with pulse-width modulated regulator, two stator current sensors, frequency-setting unit for stator field rotation and amplitude voltage, voltage correction setting unit, which contains calculating unit that produces voltage-setting correction signal in function of the calculated parameter - tangent of angle between vectors of current and electromagnetic force of stator calculated on the basis of measured stator phase currents and signals setting phase voltage for the motor. Electric drive operates with actual measured variables thus simplifying algorithm for correction signal calculation and bating demands to the process controller. |
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Electric drive with synchronous reluctance machine Invention refers to electrical engineering and can be used, for instance, in controlled electric drives of general-purpose industrial machinery and transportation vehicles. Electric drive with synchronous reluctance machine contains two groups of full-pitch polyphase windings distributed evenly along inner stator bore, at that windings of similar stator phases are interconnected in series so that special magnet axes of these winding area mutually orthogonal; beginnings of the first group windings are connected to the supply mains, while ends of the second group windings are connected to input of the non-controllable rectifier, rotor position sensor. Between anode and cathode groups of the rectifier through current sensor there are parallel-connected capacitor and a circuit consisting of in-series transistor switch with bypass diode and choke with bypass diode; output of current regulator is connected to control input of transistor switch, output of commutator switch is connected to its first input and output of current sensor is connected to its second input; the first input of commutator switch is connected to current source of preset value, while its second input is connected to output of the metre metering special voltage vector position at the engine stator, the third input is connected to output of rotor position sensor; outputs of the metre metering special voltage vector position at the engine stator are connected to phase clamps of three-phase power supply source. |
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Invention is attributed to the field of electric engineering and can be used in rotating electrical machines. According to one aspect of the version rotating electrical machine includes detector and brake. Detector is placed at the side reverse for load, rotating shaft with rotor for setting the target load in motion; it detects position of the shaft turn. Brake can be replaced at external peripheral side of detector in order control shaft. |
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Multilevel frequency converter with differential voltage levels and bypass semiconductor keys Invention pertains to electrical engineering and can be used in high voltage regulated electrical drives. Multilevel frequency converter with differential voltage levels and bypass semiconductor keys contains input multi-winding transformer, control system and several levels of power cells in each phase. Output voltage of cells for each level is different: output voltage of the first level cells is equal to half of the rated output voltage of frequency converter and each next level is twice less than voltage of the previous level. In parallel to output of each power cell there's bypass semiconductor key, one semiconductor key of power cell is connected to the first control output of the control system by commutator switch in case of the cell failure, while its other control input is connected to the second control output of the control system by commutator switch in operating modes to change output voltage of the frequency converter. |
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System of synchronous generator excitation with external boosting Excitation system includes synchronous generator (1) with armature (2) and inducer (3) windings, rectifiers (4), (15), summing transformer (5) with primary current winding (6), primary voltage winding (7), secondary winding (8) and control winding (9) and voltage corrector (10), external DC source (11), electronic key (12), current transformer (13) with shunt (14). System contains analogue-to-digital transformer (16), memory registers (17,18), pulse distributor (19), generator of pulses (20) with stable frequency, substractor (21), decoder (22), clamps (23, 24) for load connection, RS-trigger (25), differentiator (26), logic elements OR (27), AND (31), START bus (28), generator-limiter (29), inverter (30). |
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Synchronous-step motor of higher torque Each semiconductor switch of a control unit comprises four transistors, two couples of serially-parallel connected ones. At the same time in each of semiconductor switches the common point of connection of the emitter in one transistor and the collector of the other transistor in one couple of serially connected transistors is connected to the beginning of the appropriate control winding, and the common point of emitter connection in one transistor and collector connection in the other transistor in the second couple of serially connected transistors is connected to the end of the appropriate control winding. Emitters of other transistors are connected to a plus of a DC source, and collectors of other transistors are connected to a minus of a DC source. All control windings are connected at each stroke. |
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Frequency-phase system to control speed of motor rotation Control voltage controller is introduced into a frequency-phase system of electric motor rotation speed control for generation of double-phase control voltage, which provides for considerable increase of stability and efficiency of the system. |
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Device to control start and stop of induction motor Device comprises a setter of parameters, two pulse generators, an AC voltage rectifier, a voltage comparator, a voltage integrator, a width-pulse modulator and serially connected binary pulse counters, a register, a permanent memory device, a pulse shaper, a voltage switch, designed for connection into the circuit of operating voltage of the electric motor. |
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Power converter device and method of device control Power converter device is made so that its arm comprises two groups of semiconductor devices connected in series. Each group of semiconductor devices comprises a switching element and semiconductor element, different from the switching element, connected in parallel. The connection point, to which groups of semiconductor devices are connected in series, is an outlet AC lead. Both ends of the arm are DC leads. Besides, the power converter device comprises also a current sensor, a module of voltage control command generation, a module to calculate voltage drop and a module of switch control. |
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Rechargeable driven tool, control unit and record medium Driven tool comprises DC motor, switching circuit, at least one rpm setting unit, ON-duration setting unit, excitation unit, working magnitude identification unit, fault identification unit and threshold magnitude setting unit. Said fault identification unit compares working magnitude revealed by working magnitude identification unit and threshold magnitude set on the basis of working magnitude to define if working state of driven tool is faulted. Threshold magnitude setting unit sets threshold magnitude continuously or in stepwise manner in compliance with rpm set by rpm setting unit. |
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Single-phase-three-phase semiconductor reversible switchboard driven by single-phase ac circuit First outputs of the first and second semiconductor switches are connected with a phase of a single-phase AC circuit. The first outputs of the third and fourth semiconductor switches are connected with zero of a single-phase AC circuit. The second outputs of the first and third semiconductor switches are combined and connected with the start of the first stator winding and the end of the third stator winding. The second outputs of the second and fourth semiconductor switches are combined and connected with the end of the first stator winding and the start of the third stator winding. At the same time the start of the second stator winding of the motor is connected to zero, and its end - to the phase of the single-phase AC circuit. |
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Device to control excitation of ac motor Device to control excitation of an AC motor including: an inverter (INV), having multiple switched elements exposed to control by connection/disconnection, to convert DC voltage into AC voltage with required frequency, in order to excite an AC motor (6); an opening contactor (MMK) of the motor connected between the inverter (INY) and the AC motor (6); a unit (55) of preliminary detection of a switching operation for detection of the switching operation of the opening contactor (MMK) of the motor to the contact or disconnection of the main contacts and release of a signal of preliminary detection of the switching operation; and a control unit (10A), comprising a unit (70) of inverter control for control of connection/disconnection for multiple switching elements and control of disconnection for an opening contactor (MMK) of the motor and control of the inverter (INV) on the basis of the signal of preliminary detection of the switching operation. |
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Alternating-current valve inverter with distributed braking resistors Invention pertains to electrical engineering and can be used for drives and in high voltage electrical machine building. In alternating-current valve inverter braking resistance has several separate braking resistors (18) which form part of bipolar submodules (14) respectively; at that in case of in-series connection of submodules (14) they are connected in series and contain at least energy accumulator (16) connected in parallel to a matched braking resistor (18) and controlled high-power semiconductor (28) for braking which in braking position allows passage of current through respective separate braking resistor (18), and in position of normal operation mode it stops passage of current through it. |
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High-voltage frequency-controlled electric drive In the high-voltage frequency-controlled electric drive, an uncontrolled high frequency converter is connected through a multiple-winding single-phase high-frequency transformer to a controlled high frequency converter having a cellular type, wherein inputs of rectifier-inverter cells are connected to corresponding secondary windings of the single-phase high-frequency multiple-winding transformer, the primary winding of which is connected to the output of the uncontrolled high frequency converter, and the input of the latter is connected through a reactor to the mains supply. |
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Self-contained electric power supply system System has an alternating current source, a unit of three automatic tripping devices, a synchronous electric motor, a synchronous generator with an exciter, two ac voltage stabilisers and consumable units; the device is equipped with switched on first and second voltage analysers, a voltage mode control unit, an uninterrupted power supply and a switch. |
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Controlled asynchronous machine In electrical machine the second armature winding is made combined and located in stator slots of the main magnet core; it is equipped with capacitor bank. Second inductor winding is also combines, multi-phase, short-circuited; it is located in stator slots of the main magnet core. The first winding of rotor is connected to toroidal windings of auxiliary magnet core of the rotor; the first winding of stator is connected to output of frequency converter which converts electric energy of current frequency of the second armature winding to required value of control frequency and delivers it to stator winding of the main magnet core in order to create excitation current and rotating electromagnetic field with this control frequency. Control frequency is set at the output so that frequency of output current is permanent notwithstanding frequency of drive rotation. |
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Automatic control over dc motors of rolling mill master drives Invention relates to dc motor ACS. Proposed method comprises measurement of actual motor shaft rpm in rolling. Motor rpm is adjusted. Note here that measured motor shaft rpm is compared with preset one. In case inconsistency occurs, square voltage pulse opposed to deviation of motor shaft rpm it is generated and fed to motor armature. Magnitude and length of voltage are selected subject to control over minimum change in motor armature current at preset motor shaft rpm of reaching the preset rpm. |
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Invention may be used to create rectifiers for controlled electric DC and AC drives for machines to increase their efficiency, and also on transformation substations for power supply to electrified railway roads, in electric metallurgical and chemical industry to reduce the value of pulsations of rectified voltage and to reduce content of higher harmonic components in an AC curve in a three-phase grid. The proposed five-phase phase changer comprises a three-phase transformer, having three coils of the primary winding, which are connected as a star network, and are connected to the three-phase grid with a zero wire "0", six joined main coils of the secondary windings, one additional coil of secondary winding and taps from turns of the main coils of the secondary windings, which jointly with the output clamp of the additional coil of the secondary winding create a symmetrical five-phase system of voltages. Each main coil of the secondary winding of the transformer is a side of a "hexagon" A, B, C, D, E, F, transforming a symmetrical three-phase system of voltages into a symmetrical six-phase system of voltages, at the same time the additional coil of the secondary winding with its beginning is connected to the unit of the "hexagon" circuit, which is not connected with the main coils of the secondary winding of the phase, on the rod of which there is the additional coil of the secondary winding. |
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Method of automatic control over ac electric locomotive rheostat brake Invention relates to railway transport. Proposed device comprises controlled rectifier connected with AC system incorporating traction motor winding current transducers and locomotive speed transducer, driver signal comparators and those of said transducers. Additionally, said device comprises computer of the ratio between armature winding mean current and excitation current and computer of difference between traction motor armature winding maximum and minimum currents connected to comparator of excitation current control channel and with pneumoelectric gate of sand feed valve. |
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Device for start-up and brushless excitation of non-contact synchronous machine Device includes the main synchronous machine (1), inversed synchronous exciter (2) of the main synchronous machine in a common magnetic system with an asynchronous subexciter made in the form of an asynchronous motor, excitation winding of the synchronous exciter, winding located on the rotor, a rotating semiconductor converter and an excitation control. It is equipped with switching device of modes (7), metre (8) of rotor rotation frequency of the main synchronous machine with an inlet and an outlet and winding switches (9, 10). Winding is made in the form of coil groups in a non-salient pole magnetic system of the stator and the rotor, and the magnetic system is combined as to magnetic flows with smaller number of poles for motor operation and large number of poles for generator operation. |
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Device for emergent rheostat braking with two-pole resistive unit and permanent magnet drive Invention relates to emergency braking device for electrically driven carrier. Proposed device comprises electromechanical machine with permanent magnets and electric contacts, resistive device and electromechanical switch. Said electromechanical switch is intended for emergent connection of machine contacts with brake torque generator. Resistive device includes one or multiple dissipation resistors and current inverters. Said inverters incorporate no active power switches. Dissipation resistors are connected with two connection terminals either directly or via passive nonelectronic elements. |
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Three-phase asynchronous welding generator with three stator windings In stator slots of three-phase asynchronous welding generator there is laid excitation winding (1), operating windings (2) and (3). Excitation capacitors (4) are connected to excitation winding (1); compounding capacitors (5) and the first rectifier (6) are connected to operating winding (2); the second rectifier (7) and controlled inductor (8) are connected to operating winding (3). Outputs of rectifiers (6) and (7) are connected in parallel to welding electrode (9). Rotor (10) of generator is caged. |
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Three-phase asynchronous welding generator with electric coupling of stator windings In slots of three-phase asynchronous welding generator with cage rotor (1) there is laid operating winding (2) and excitation winding (3). To start of operating winding (2) end of excitation winding (3) and rectifier (6) with electrode (7) are connected. To start of excitation winding (3) excitation capacitors (4) are connected. To the end of operating winding (2) compounding capacitors (5) are connected to a triangle connection. Possibility of overvoltage occurrence is stipulated by electric coupling between stator windings. When emergency overvoltage occur overvoltage protection device (8) is actuated; this device is connected to output of rectifier (6), it impacts on commutation device (9) which trips excitation capacitors (4) from excitation winding (3). |
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Device of electromechanical control Device of electromechanical control includes the second induction motor and the second block of three automatic splitters. The first, second and third outputs of the block from three switchboards are accordingly connected with the first, second and third inputs of the second induction electric motor, rigidly connected to the first induction electric motor, and the first, second and third outputs of the induction generator are accordingly connected to the first, second and third inputs of the second block from three automatic splitters, having the first, second and third outputs of which accordingly connected with the first, second and third inputs of the first block from three automatic splitters, the fourth, fifth and sixth outputs of which are accordingly connected to the first input of the first AC voltage stabiliser, with the second inputs of the first and second AC voltage stabiliser and with the first input of the second AC voltage stabiliser and having a separate input connected to the output of the motor control panel. |
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Regulator of three phase current Regulator of three-phase current comprises three branches with a respective input (U1, V1, W1) and output (U2, V2, W2), with five pairs (1, 2, 3, 4, 5) of connected antiparallel valves for reversing the magnetic field. The first input (U1) via the first pair (1) is connected to the first output (U2), the second input (V1) via the second pair (2) is connected to the second output (V2) and via third pair (3) to the third output (W2), and the third input (W1) via the fourth pair (4) is connected to the second output (V2) and via the fifth pair (5) with the third output (W2). As a damping circuit, to each input (U1, V1, W1) and each output (U2, V2, W2) there is a resistive-capacitive half-link connected so that one end of the respective resistive-capacitive half-link is connected to a corresponding input (U1, V1, W1), accordingly, with the output (U2, V2, W2), and so that the second ends of these resistive-capacitive half-links are connected with the help of a cross connection (Q). |
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Device to stabilise voltage and frequency of wind-electric plant Voltage stabilisation system (10) comprises a unit of excitation capacitors (11), a rectifier (12), a transistor (13), a pulse amplifier (14), a transformer-rectifier unit (17). Inlets of the transformer-rectifier unit (17) are inlets of the voltage stabilisation system (10), the outlet of the transformer-rectifier unit (17) is connected with the first inlet of the pulse shaper (15), and its second inlet is connected with the outlet of the clock oscillator (16), the outlet of the pulse shaper (15) via the pulse amplifier (14) is connected to control electrodes of the transistor (13), an emitter-collector transition of which is connected to the inlet of the rectifier unit (12), the outlet of the rectifier unit (12) is connected to the outlet of the asynchronous generator (5) via the unit of excitation capacitors (11). The frequency stabilisation system (9) comprises a transistor (21), a pulse generator (18), a transformer-rectifier unit (20) and a pulse amplifier (19). |
Another patent 2513353.