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Filtering and compensating device for transmission of high-voltage direct-current energy Invention relates to electrical engineering. In the device adjustment of reactive power is carried out by switching of two or more branches, each of them is equipped with a switch for connection to the supply mains and includes capacitor banks, resistors and chokes performing functions of filtration and compensation. The device contains also one or more active elements. The capacitor banks of the device are connected to the ground through a common active element by the respective quantity of medium-voltage switches or through separate active elements and they perform the function of compensation only. The filtration functions are performed by one active element only; to this end in addition to a common set of functional units the active element balancing system is equipped with three programmable specific functional units: damping unit D, balancing unit B, unit S of selective harmonic suppression which generate driving voltages, and sum of the latter ones forms the main variable for control of the converter. |
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Invention is related to the field of engineering and may be used in uninterrupted power supply (UPS) systems and inverters. The method and device solving the problem of mismatch between UPS systems of non-sinusoidal oscillations and loads with active power factor compensation (PDC) includes the following stages when non-sinusoidal oscillations to be delivered as a load (e.g., voltage fluctuations) are generated with relative pulse duration of pulse-width modulation (PWM); discretisation of these non-sinusoidal oscillations to accumulate output signal readings and regulation of relative pulse duration to control non-sinusoidal oscillations depending on output signal readings in order to deliver the desired signal characteristic (e.g., mean-square signal level) as a load. In the embodiments the relative output pulse duration is regulated in different ways in case of growing and lowering power consumption by the load respectively. |
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Multilevel converter as reactive power compensator with active power balancing Application: in the field of electric engineering. A multilevel converter (7) has several converting lines (8-10) which are wye- or delta-connected to phases (2-4) of the three-phase network. On the basis of phase voltage (U2-U4) values and phase current (IL2-IL4) values an active component (w) and at least two asymmetric components (w', b') are determined. The active component (w) and at least two asymmetric components (w', b') are filtered by means of the respective filter response. The phase voltage (U2-U4) values are multiplied by the component (w) and by at least two components (w', b'), whereupon they are multiplied by the respective weight coefficient (ga-gc) and the result is applied to the phase current (IL2-IL4) values. Current (I0) is determined in the neutral wire on the basis of components (w', b') and values (U2-U4) and applied to the phase current (IL2-IL4) values. Based on the phase current (IL2-IL4) values modified in this way the control state (A) is defined for the converting lines (8-10). The converting lines (8-10) are thus controlled respectively. |
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Reactive power control systems, devices and methods Invention is related to the field of electric engineering and may be used for reactive power control in power supply systems for such devices as digging machines of different type, which are used for mining operations. The approximate defined embodiments can provide an adapted system, a device, manufacture, a scheme and/or a user interface and/or a method and/or a machine-readable medium containing instructions for activities that can contain by means of the preset data device for the preset digging machine consisting of a variety of active input cascades, at that each active input cascade is coupled electrically to the AC power mains of the above digging machine, each active input cascade is adapted to supply DC power to the DC bus, the above DC bus is coupled electrically to a variety of inverters and each inverter is adapted to supply AC power to at least one operating motor, an active power control is formed by each active input cascade in an independent way. |
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Control method and control device used for shunting of power supply units Control method for shunting of power supply units includes the following steps: measurement of the first three-phase output eclectic signal; calculation of the first direct and reverse sequences of the first three-phase output eclectic signal; generating of the preset components for direct and reverse sequences of phases in order to perform automatic compensation for the components of the first direct and reverse sequences thus outputting components of the second direct and reverse sequences; summing-up of the second direct and reverse sequences and output of the second three-phase output eclectic signal in the preset mode. |
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Static reactive power compensator In the static compensator, the controlled inductor is a double-winding transformer with a magnetic conductor saturation controller, wherein the nominal input resistance of the transformer is 1.5-6 times greater than the sum of inductive resistances of its windings reduced to the nominal voltage; a device for filtering higher harmonics is in form of a filtering-compensating device, the nominal power of which ranges from 0.1 to 0.5 of the nominal power of a capacitor bank, and the sum of nominal power values of the filtering-compensating device and the capacitor bank is equal to the nominal power of the transformer. |
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Device for compensation of reactive capacity Invention refers to power factor improvement for consumers, in particular, for alternate-current electric stock with zone-phase voltage regulation. The declared invention contains voltage transformer, load, source of reactive power that represents in-series connected inductance L, capacitance C and two back-to-back thyristors, voltage sensor, current sensor, sync pulse unit, control unit, unit of pulse and phase control, unit of controlled current calculation, unit for calculation of actual current value and comparator. |
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Intergrated apparatus for compensation of reactive power and melting ice cover (version) Apparatus has a three-phase bridge converter on fully controlled semiconductor rectifiers, which are shunted by anti-parallel connected diodes, a capacitor bank at the direct current side, a first three-pole switch and two series-connected three-phase chokes, one of which is connected in parallel to a second three-pole switch, at the alternating current side. According to the first version, the capacitor bank in reactive power compensation mode is connected by contacts of a third three-pole switch, which are open in ice melting mode, to emitter (collector) leads of rectifiers of the converter which in that mode are connected through a fourth three-pole switch to wires of the overhead power line for controlled melting of ice with alternating current. According to the second version, the capacitor bank in reactive power compensation mode is connected by contacts of the third and fourth three-pole switches, which are open in ice melting mode, to emitter and collector leads of rectifiers of the converter which in that mode are connected through fifth and sixth three-pole switches to wires of two overhead power lines for simultaneous controlled melting of ice thereon with alternating current. |
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Integrated apparatus for melting ice and compensation of reactive power Integrated apparatus has two three-phase bridge converters on fully controlled semiconductor rectifiers, which are shunted by anti-parallel connected diodes, a capacitor bank at the direct current side of the converters, a first three-pole switch and two series-connected three-phase chokes, one of which is connected in parallel to a second three-pole switch - at the alternating current side. When melting ice, the first converter operates in a controlled rectifier mode and the second converter operates in self-contained voltage inverter mode, the output of said inverter being connected through a third three-pole switch to wires of the overhead power line which are closed at the opposite end, for simultaneous melting of ice thereon with low-frequency alternating current, where the inductive component of the resistance of the wires almost has no effect on the effective melting current value. |
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Apparatus for compensation of reactive power and melting ice cover Apparatus has bidirectional high-voltage thyristor valves (1, 2, 3) connected in series to reactive elements (chokes or capacitors) (4, 5, 6). Switching from the reactive power compensation mode to the ice cover melting mode is carried out with two switches (7, 8). To this end, points of connection of the reactive elements (4, 5, 6) and thyristor valves (1, 2, 3) are connected to a three-phase mains supply A, B, C; the free terminals of said valves (1, 2, 3) are connected through contacts of the first switch (7) on a delta circuit to free terminals of the reactive elements (4, 5, 6), and through contacts of the second switch (8) to wires of the overhead line for melting ice cover. |
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Mast power plant-compensator of reactive power of overhead power transmission line Mast power plant-compensator comprises a synchronous generator, connected to an overhead power transmission line via a controlled disconnector, and a gas internal combustion engine, installed on a "АП"-shaped support of vibration-resistant design. The disconnector is made with an individual manual drive. The power plant is equipped with devices for control and monitoring of parameters of an overhead power transmission line, and also a disconnector of a synchronous generator, a valve of gas supply and a friction clutch coupling, having individual electromagnetic drives, activated with a control device. The friction clutch coupling connects or disconnects the shafts of the synchronous generator and the gas internal combustion engine. |
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Device for non-contact transfer of electric energy to underwater object (versions) Device (versions) includes the following main elements installed in an inverter unit on a carrier ship: a single-phase independent inverter of increased frequency voltage, a control unit of the above inverter, an input capacitor and the primary winding of an increased frequency transformer, as well as secondary winding of transformer, single-phase bridge uncontrolled rectifier, smoothing reactor and output capacitor, which are located in the rectifier unit on an underwater object; besides, windings of increased frequency transformer are equipped with flat magnetic screens as per the first version and with bowl-shaped cores and central rods as per the second version. |
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Filtration and compensation device of traction ac energy system Filtration and compensation device of a traction energy system comprises serially connected the main switch with a closing auxiliary contact and a control panel for its connection, the first reactor and the first section of capacitors, the second section of capacitors with the parallel connected second reactor, and the third section of capacitors with the third reactor and a damping resistor connected between a point of connection of the second and third sections of capacitors and the rail. The device design includes a contactor with a drive connected between the third reactor and the rail, and the circuit of contactor connection connects the control panel with its drive via the closing auxiliary contact of the main switch. |
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Method for control of power-factor correction unit in supply mains According to the method instantaneous values of three-phase mains are measured; selected harmonic components of the current are defined; phase-by-phase summation of harmonic components is made; correction current values are formed for each phase of line current which contains the selected harmonic components and having phase shift per 180 electric degrees and by means of respective current values delivery to each phase compensation of harmonic components for the line current is achieved. |
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Abruptly variable load reactive power sensor for controlling static reactive power compensator Reactive power sensor, having a current signal multiplier of the given phase of abruptly variable loads of the network and a reference sinusoidal voltage, cascade-connected band-elimination filters connected to the output of the multiplier, a low-pass filter connected to the output o the last band-elimination filter of the cascade, and a phase corrector connected to the output of the low-pass filter, according to the invention, further includes a differentiator, to the input of which a current signal is transmitted, and the output is connected to the current input of the multiplier, wherein the vector of the reference voltage of the multiplier is phase-locked to the vector of the voltage of given phase of the load. The differentiator is in form of an operational amplifier (DA) with a negative feedback through a resistor (R), to the inverting input of which the current signal is transmitted through a capacitor (C), and the non-inverting input of which is connected to the common bus (zero point). |
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Device of reactive power compensation Device comprises a shunting capacitor tank of static capacitors, including serially connected capacitors, one input of the tank is connected to a linear bus, and the other input - to grounding, a closing breaker connected in parallel to a part of capacitors arranged at the side of the grounded input, besides, one input of the breaker is connected on the ground potential, and a controlled shunting reactor. At the same time the ratio of capacities of the controlled shunting reactor and a part of the capacitor tank meets the following condition: Qcsr≥Qsct, where Qcsr - controlled reactor capacity, and Qsct - capacity of a shunting capacitor tank of static capacitors with the disconnected closing breaker. The range of reactive power variation is expanded (instead of the range from -Qsctmax to 0, there is a range from -Qsctmax to +Qcsr). |
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Method of converter operation and device for implementation thereof In the method of operation of a converter comprising a converting unit with multiple controlled power semiconductor switches and connected with an electric grid of AC voltage, controlled power semiconductor switches are controlled by means of a control signal (Sa), generated from a control signal (Sr). The control signal (Sr) is generated by control of an H higher harmonic of grid currents (iNH) to the specified value (iNHref) of grid current, where H=1, 2, 3,…. The specified value (iNHref) of grid current is generated by control of the value of the specified value (uNHref) of grid voltage, at the same time the difference (uNHdiff) of control between the H higher harmonic of grid voltages (unh) and the specified value (uNHref) of grid voltage is assessed with the help of impedance (yNH) of the grid detected in respect to the H higher harmonic. |
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Filter-compensating device comprises a three-phase load connected as "star", a compensation unit from three LC-circuits with fixed parameters, a switch, and three current sensors, a three-phase booster transformer, a rectifier, a device for calculation of reactive power, three autonomous voltage inverters, a three-phase measurement voltage transformer, a synchronisation device, a system of inverters control, which are in a certain relation with each other. |
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Device contains a booster transformer placed on the substation HV side and controlled from the voltage amplitude and phase converter with an intermediary DC link. The converter is fed from the load. The discrete stage of reactive power compensation is the network cosine capacitors bank. In case of the RL-load high inductance the inverter operates in a leading phase, supplementing the capacitors' action while in case of low inductance it operates in a lagging phase, neutralising the action with the discrete stage. |
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Reactive power compensation device (versions) Device contains a chain of serially connected capacitor banks and a reactor as well as pairs of anti-parallel connected thyristors; in the first version, a pair of anti-parallel connected thyristors is joined up parallel to the reactor. In the second version, one pair of anti-parallel connected thyristors is joined up parallel to the reactor while another pair of anti-parallel connected thyristors is serially introduced into the circuit connecting the capacitor bank and the reactor. |
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Adjustment method of compensation of capacitance fault-to-ground currents in electric networks For determination of the network zero-sequence circuit parameters the transitory process free component is used carrying complete information on the circuit proper frequency and goodness and isolated from the neutral offset voltage; for generation of a pedestal current pulse within the network circuit a source with low installed capacity is used in high on-line time ratio mode. This method ensures the required accuracy of setting to any specified compensation mode within the whole range of the ground-fault neutraliser inductance adjustment, inter alia - in networks with combined neutral grounding. It involves no limitations as to the type of the ground-fault neutraliser applied. |
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Capacitor plant for automatic compensation of reactive power Proposed invention relates to electrical engineering, in particular, to electrical distribution equipment, and serves for compensation of reactive power in automatic mode under alternating load conditions. A plant comprises an input three-phase four-wire bus (1) for connection to a source of supply, an output three-phase bus (2) for load connection, three current transformers (3), a reactive power controller (4), K control stages (5), comprising three bidirectional keys (6) and three capacitors (7) each, a charging-discharging device (8) with a function of compensation of capacitor leakage currents. Control signals for connection of appropriate keys are sent at the moments, when linear voltage, to which a specific capacitor (7) connects, reaches an amplitude value, at the same time difference of potentials on the key (6) at the moment of connection is close to zero. Disconnection of the specific capacitor (7) also takes place at the moment when linear voltage, to which a specific capacitor connects, reaches an amplitude value, at the same time current flowing through the key (6) is close to zero. The described logic of switching capacitors (7) with keys (6) makes it possible to minimise switching surges of currents and voltages. |
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Device and control method for transfer of power Device is composed of the following components: a converter (118), having an AC side and a DC side, a switch (112), arranged as capable of connection to a transfer line (104) on the first side and arranged as capable of connection of a load (122) on the second side, besides, the second side also connects to the AC side of the converter, a device (120) of power accumulation connected to the DC side of the converter. In the first mode of operation the switch is closed in such a manner, so that the current of power accumulation passes to or from the power accumulation device for its charging or discharging, accordingly, using the converter for any required conversions between the AC and DC. In the second mode of operation the switch is opened, preventing current leakage from a transmission line to a converter, and the power accumulation device sends DC, which is converted by the converter into AC. Besides, in the first mode of operation the device is configured so that transfer of power along the transfer line corresponds to the natural capacity of the transfer line under action of the power accumulation current. |
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Single-phase active electric filter Active electric filter comprises a system of input information conversion connected with an input of an error signal generation system synchronised with the grid. The output of the error signal generation system synchronised with the grid is connected to an inverter. The inverter output is connected to the input of a pulse-width modulator (PWM). An input of a buffer cascade is connected to the PWM output, the outputs of the buffer cascade are connected with inputs of a pulse power amplifier, and an input circuit of an LC-filter is connected to the output of the pulse power amplifier. Outputs of the LC-filter are connected to a phase of a supply grid. A single-phase active electric filter makes it possible to use cheap power modules on the basis of key MOSFET-transistors, best frequency properties of which make it possible to increase a clock frequency of PWM, to simplify output LC-filters, and therefore to improve the power quality. |
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Application: in electric engineering. The reactive power compensator includes three-phase voltage divider and single-phase current transformers connected to power system phases. Voltage sensors are connected to three-phase voltage divider output. The reactive current sensors are coupled with single-phase current transformers output. The outputs of reactive current sensors and voltage sensors are coupled with a comparison elements input with their output being connected to inverters. The inverter outputs are linked with control signal generators with their inputs being connected with differential amplifiers, and their inputs are connected to the power modules coupled with capacitive filters having their outputs connected to power system phase. |
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Active filter with multi-level topology Low cost device (1) is proposed to affect electric energy transmission to multi-phase a.c. lines (2) with phase modules (5a, 5b, 5c), containing, accordingly, a.c. contact output (6a, 6b, 6c) to connect to one phase of the a.c. line (2) and two terminals (7p, 7n). Besides, there is a phase module side (8ap, 8bp, 8cp, 8an, 8bn, 8cn) between each connecting terminal (7p, 7n) and each contact a.c. terminal (6a, 6b, 6c). The side is comprised of a sequentially connected sub modules (9), which accordingly include a power semi-conductor-based circuit and an energy storage system (15), connected in parallel to power semi-conductor-based circuit. Besides, the connecting terminals (7p, 7n) are interconnected, and power semi-conductor-based circuit includes interruptible power semi-conductors (13), which are coupled with each other based on half-bridge circuit. |
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Device of static compensator of reactive capacity Device of a single-phase static compensator of reactive power comprises a compensator circuit comprising the first static compensator of reactive power connected in series with a thyristor valve. The compensator circuit is made as capable of connection with its first end to one phase of a transmitting circuit of nominal voltage that exceeds 69 kV. Besides, the thyristor valve comprises multiple thyristors connected in series, and the compensator circuit is made as capable of direction connection with a transmitting circuit, which makes it possible to exclude a transformer. Also an appropriate three-phase device is described. |
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In the method to increase a power ratio reactive and active components of current are redistributed inside each phase of an asynchronous generator with a short-circuited rotor during its operation in parallel with the grid. The reactive component of the phase current is reduced by lowering the linear voltage of the grid relative to the rated linear voltage of the generator by one stage based on the following: therefore it becomes possible to increase the generator load and its power ratio. The active component of the phase current increases within the limits of the rated value of phase current during operation of an asynchronous generator by increasing power supplied to a shaft of the asynchronous generator at the side of its drive engine of a power plant to convert mechanical energy into electrical one. |
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Control method for reactive power compensator Upper and lower limits should be set for reactive power for the purpose of voltage regulation of each tractive motor operating area. Supply voltage is determined for reactive power sources. Locomotive current and voltage values are measured and then reactive power is calculated and compared with its upper and lower limits. When reactive power of electric locomotive is less than lower limit then reactive power source will be switched on/off to power supply source with less voltage. When reactive power of electric locomotive is more than upper limit then reactive power source will be switched to power supply source with bigger voltage. |
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Device to convert an active load is proposed, comprising two power diodes oppositely connected to a phase conductor of an electric network, each of them is connected accordingly to two accumulating capacitors of identical size connected to a zero conductor of the electric network, from two serially connected power thyristors, ends of which are connected accordingly to points of connection of power diodes and appropriate accumulating capacitors, the middle point of power thyristors connection is connected together with the zero conductor of the electric network to a controlled active load, and a transformer is used to control power thyristors, the primary winding of which is connected to the electric network, its two separate secondary windings are connected to cathodes and control electrodes of the power thyristors via circuits from serially connected limiting diodes and resistors, besides, outputs of the secondary windings of the transformer connected to the control electrodes of the power thyristors, are antiphased, which determines discharge of one of accumulating capacitors to the controlled active load, when the other accumulating capacitor is charged. The device eliminates losses of power supplied along conductors of the electric network from a remote electric substation related to reactive currents, value of which at the same time is minimised. Besides, the minimisation process may be automated by application of the appropriate tracking system. Such system may be used also in low-current equipment. |
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Device and method to supply energy to critical load Device of high-voltage energy supply comprises the first and the second converters (20, 30) of voltage, connected in series, besides, a power accumulator (10) is connected to the DC side of the first voltage converter, the load is connected to the AC side of the second voltage converter, and a power generator (40) is connected to the AC side of the second voltage converter (30), the high-voltage power supply device is made as capable of connecting the load to the AC side of the first voltage converter, besides, the high-voltage power supply device comprises a bypass line (42) for the generator (40), with the help of which the generator may be connected directly to the grid (60). Connection of the load to the AC side of the second voltage converter, and the generator - to the second converter, provides for instantaneous power supply during power interruptions. |
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Thyristor-controlled series capacitor damping subsynchronous resonances Control unit (17) for a thyristor-controlled series capacitor connected to a electric power transmission line (12) comprises a control unit integrating a thyristor start control (18) and a generator of required voltage of the capacitor passing through zero depending on line current and voltage of the capacitor in response on a command signal, and a command control (19) which is used to generate the command signal for the thyristor start control, and accommodates a command damping control (24) comprising a damping unit at least on one discrete frequency. |
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According to the method, the reactive magnetising current is reduced in a power winding of electromagnet devices by means of an electric circuit reactive current. At the same time the circuit is isolated from the power winding, the power winding and the circuit elements are laid onto a magnetic conductor assembled from steel sheets isolated from each other. An additional winding is used as one of circuit elements, the second element is a reservoir of a charge core, onto which the power and additional windings are laid, and the reactive magnetising current is developed in the circuit. Also a device for the method realisation is proposed. |
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Three-phase compensator of reactive power Three-phase compensator of reactive power is connected to a three-phase load and comprises a power inverter unit, comprising a three-phase transformer, a unit of autonomous voltage inverters and a source of reactive power. The control system includes a unit of active and reactive power calculation, a unit to calculate specified values of phased currents, a unit to control autonomous voltage inverters and a unit to calculate a variable component of active and reactive power, a device to recharge a source of reactive power, a device to calculate the specified voltage, an element of comparison, a PI controller, a unit of the recharging device control and a voltage sensor. The first outlet of the unit of active and reactive power calculation is connected to the inlet of the device of the specified voltage calculation, the outlet of which is connected to the first inlet of the comparison element, the outlet of which via serially connected PI controller and unit of the recharging device control is connected to the second inlet of the latter. The second inlet of the comparison element is connected to the outlet of the voltage sensor, the first and second inlets of which are connected to the source of the reactive power. |
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System of static compensator for providing electrical network with reactive and/or active power System includes static compensator (11) which contains direct current capacitor (Ud) and voltage converter (10) of the supply. Static compensator (11) is connected to energy accumulation device (12). In addition, system includes device (13) of intermediate converter, which is connected in series with energy accumulation device (12) and parallel with direct current capacitor (Ud) of static compensator (11). Device (13) of intermediate converter and device (12) of energy accumulation are also in-parallel connected to voltage converter (10) of source of static compensator (11). |
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Method to compensate high harmonics and correction of grid power ratio Method consists in generation of pulses of control of power keys of inverter with application of phase synchronisation of voltage and current of grid, processing of signals from sensors of voltage by phase converter to phase synchronisation of voltage and current. At the same time output signals from sensor of grid current arrive at the inlet of the first additional phase converter, output signals of which together with output signals of unit of phase synchronisation arrive at inlet of the second additional phase converter, output signals from which together with output signal of accumulating capacitor voltage controller and output signals of unit of phase synchronisation arrive at the inlet of unit of voltage shapers, output signals of which arrive to inlet of phase converter, output signals of which together with output signal of voltage controller of accumulating capacitor arrive at the inlet of unit of relay controllers. |
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Method of power grid conditioner control Input voltage and current of single-phase circuit are measured, voltage signal is multiplied by control signal and compared to signal of circuit current sensor. Produced difference signal is used to control pulse-width modulator of power channel of conditioner. Power channel of conditioner is two-cycle inverter with bipolar supply, which is connected to electric circuit in parallel between primary source of voltage and load. The first output of inverter is connected to phase conductor of circuit in point between current sensor and load. Other output of inverter is connected to neutral line. Between point of connection of inverter with phase conductor and load, the second current sensor is connected (circuit of positive feedback by load current), output signal of which is rectified and integrated and then used for multiplication by signal of circuit voltage. Result of multiplication is compared to signal of the first current sensor (negative feedback), and produced difference signal is used to control pulse-width modulator, generating two control signals for pulse switches of inverter in antiphase. Each of switches commutes voltage of appropriate polarity to load, which is then filtered with the help of L-shaped filter. Maximum output current of inverter is limited by limitation of instantaneous value of current of each inverter switch. Initial value of efficient value of output current of conditioner is specified by setting a division ratio for value of voltage sensor output signal. Conditioner is supplied from the same circuit, connecting it to points of phase conductor and neutral line or from other circuit. |
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Device for automatic tuning of arc-quenching reactor Tuning device, comprising amplitude or phase detector of unsymmetry vector, additionally includes an element for measurement of own frequency of controlled circuit, which determines signal of arc-quenching reactor inductance control. Device arrangement is provided with auxiliary generator of artificial excitation pulses, and it may also be connected into circuit of controlled loop. |
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Method for group control of switch voltage adjusters (versions) In a method for group control of individually loaded switch voltage adjusters connected to a single power supply, a common period of pulse-length modulation, independent variation of pulse duration during which the adjuster activates the load to power supply; in each modulation period, the adjusters are divided on two groups equal for total pulse durations or total products of load current and pulse duration of the adjuster, and the first group loads in the ascending order of input currents and then the second group loads in the decreasing order of currents are connected to the power so that to combine a pulse start of every adjuster with pulse termination of the previous adjuster. |
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Power compensator and method for providing reduction start-up with this compensator Power compensator (1) for electric energy transmission line (3) includes converter (4) of voltage source, device (6) of capacitor and energy storage device (5). Energy storage device includes high-voltage battery means having failure mode of short circuit, first (40a) and second main switch (40b) to disconnect the battery means from capacitor means, and control unit (44) to control the first and the second switches. |
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Adjustment method of compensation of capacitance fault-to-ground currents (versions) In method of adjustment and compensation of capacitance fault-to-ground currents in order to control maladjustment, there used is data on free frequency and maladjustment degree of zero sequence circuit (ZSC) of network and implementation of measurement algorithm with processing of control signal in temporary area, which does not depend on unstable asymmetry vector. This method can also be used in networks with reduced factor of quality of ZSC, namely in networks with combined grounding method, where compensation systems on the basis of extreme and phase control methods are inefficient. |
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Device for power supply of underground object from board of carrier vessel Device for power supply of underground object from board of carrier vessel comprises the main elements: the following components installed on carrier vessel - step-up transformer, controlled voltage rectifier, communication line; the following components installed on underground object - pulse converter of DC voltage, DC buses, loads, autonomous voltage inverter, secondary pulse DC voltage converter, second part of loads, which consume AC, third part of loads, which consume DC with low voltage value. |
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Temperature controller, to provide heat to device (5) of energy accumulation in power compensator (1), where device of energy accumulation comprises multiple blocks (7) of high-temperature battery with high potential, comprises pipeline network to locate coolant, which includes circuit (17) of the main pipeline and circuit (18) of local pipeline in each block of battery, besides each circuit of local pipeline has the first end (11) to produce coolant and the second end (12) to discharge carrier, besides circuit of the main pipeline comprises source (22) of heat and fan (20), and pipeline network comprises connection pipe (19), which connects each end of each circuit of local pipeline with circuit of the main pipeline to provide for continuous flow of liquid coolant. |
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Controlled source of reactive power High-voltage transistors with maximally simplified control circuit and temperature stabilisation are connected in controlled source of reactive power directly into circuit of controlled battery. |
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Compensation device for current distortions and reactive power Device includes power unit and monitoring and control system, where power unit includes DC-to-AC transformer based on IGBT inverter with power accumulator in the form of condenser connected at DC side of the transformer, and integration filter linked to AC output terminals and connected to network over protection and cushion start unit, and monitoring and control system containing first and second current sensors and pulse-width modulation unit, with first current sensor connected at load input and second current sensor connected between transformer output and integration filter input, is supplemented with voltage sensor connected over respective analog-to-digital converter to respective inputs of digital processing unit, output of which is connected to pulse-width modulation unit input over digital-to-analog converter unit, with pulse-width modulation unit output connected to transformer input. Digital processing unit includes interconnected digital down-converters, amplitude and phase detectors, synthesisers and adders, with inputs of respective digital down-converters and respective adder serving as digital processing unit input and output of another respective adder as digital processing unit output. |
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High-voltage overhead line with connected shunting reactors Application: in the field of electrical engineering. In high-voltage overhead line that comprises uncontrolled shunting reactors connected to busbars of the line via switches, controlled shunting reactor is installed additionally, for instance controlled by magnetisation and connected to busbars of the line. Range of reactive power control in controlled reactor is identified by the following ratio: qmax≥Qcrmax≥0.9Qmax, 0>crmin≤0.1Qmax, where Qcrmax - maximum reactive power of controlled reactor, Qcrmin - minimum reactive power of controlled reactor, Qmax - maximum power of reactor of any of uncontrolled reactors. |
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Arc-suppressing reactor with controlled magnetic gap "rdmr" Invention relates to devices for compensation of capacitance current of ground fault in electric circuits with isolated neutral. Reactor comprises the following components arranged in tank (1) with transformer oil - current transformer (9), magnetic conductor with controlled magnetic gap (3), main winding (6) and secondary windings: signalling one (7) and additional power one (8). Leads of windings and transformer (9) are arranged on external surface of tank (1). In body (24) of current indicator (13) there is a runner (27) arranged, which moves jointly with upper movable core (4). Unit of mechanical braking of magnetic gap controller movement mechanism from upper (22) and lower (23) blocking contacts and stop (28) is introduced, being installed inside tank (1) and fixing core (4) in extreme upper position at the distance from upper cover (10) of tank (1). Blocking contacts (22, 23) are installed in body of current indicator (13). Runner (27) indicates value of reactor inductive current by scale (26). In extreme upper or lower position runner (27) rests against blocking contact (22 or 23). Contacts (22, 23) via terminal box (21) disconnect supply of electric motor (29) of movement mechanism (11). |
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According to the method the control process of power coefficient in the main n-phase network and adjustment process of the latter is performed simultaneously and subsequently in two steps. At that, reactive power at the first step, which is necessary for consumer, is compensated only in one phase chosen as a reference one by bringing power coefficient to necessary value. The latter is performed by means of additional n-phase power source by means of generation to reference phase - current, with necessary modulus and phase angle. Missing reactive power in the rest (n-1) phases is compensated by means of the above additional n-phase power source by adjusting the latter relative to reference phase current. |
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On the basis of container-type converting device there can be built combined installation for glase ice melting on wires and wire ropes of overhead electric lines and compensation of reactive power; switching over from melting mode to compensation mode is performed in it with minimum number of commutations of power equipment, and equipment itself allows installation on outdoor substation. Device includes thyristor modules located inside transport container, phases of converter bridge, which are assembled into a circuit, thyristor module control units, connector with electromechanical drive, which is connected parallel to poles of converter bridge phase, and system of forced air cooling, as well as primary control system located outside container; at that, anode, cathode and phase terminals of converter bridge phase forms both signals to control units of thyristor modules, and control signals of electromechanical drive for opening or closing the connector. |
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Device for reactive power compensation Invention relates to electrical engineering and can be used in AC electric stock. In each half-cycle the first (7) or second (8) diodes change into conducting condition, at the same time the second (10) or the first (9) thyristor also changes to conductive condition, since control unit (6) sends control pulse to electrode of thyristor control. As voltage passes over "zero", voltage detector (5) generates a signal, which causes zeroing of the first timer included into control unit (6) and registers constant into the second timer of control unit (6). As current passes over "zero", current detector (4) generates signal, which causes fixation of content in the first timer of control unit (6), at the same time number recorded in this timer is proportional to clock frequency of control unit (6) and angle of current phase shift. The second timer of control unit (6), where constant is recorded in the beginning of half-cycle, continues counting for subtraction until its content becomes equal to content in the first timer of control unit (6). If values of the first and second timer are equal, control unit (6) generates control pulse to disconnect the first (9) or second (100) thyristor. |
Another patent 2513951.