93 results about "Reactance" patented technology

The invention discloses a controllable current-limiting reactance protection device, a control method, electronic equipment and a medium. Relates to the field of transformers, and solves the problem of low speed of current-limiting protection of an energy storage type distribution transformer. The working state of a power grid circuit is monitored in real time, on and off of a switch tube are rapidly controlled, and the impedance of an access circuit is adjusted, so that the rise rate and the first peak value of fault current can be greatly reduced, an energy storage system and a distribution transformer are prevented from being damaged, and due to the fact that the switching speed of the switch tube is far higher than that of a mechanical switch, the reliability is high. Moreover, fault signals do not need to be analyzed and processed, connection and disconnection of a switching tube are directly controlled, the fault processing speed is also improved, effective current-limiting protection is provided for the energy storage type distribution transformer within a short time when the fault occurs, the current-limiting protection is not affected by operation delay, and the service life of the energy storage type distribution transformer is prolonged. The reliability and the stability of the energy storage type distribution transformer in a micro-grid environment are remarkably improved, and a powerful guarantee is provided for safe and stable operation of a power system.

The invention belongs to the technical field of low-voltage power distribution, and particularly relates to a control method and system for low inductive reactance and low transient impulse voltage, the magnetic flux density and the change rate of a magnetic core are collected in real time through a sensor, a dynamic threshold value is calculated based on the magnetic flux density, and the critical point of the magnetic core entering a nonlinear magnetization area is accurately identified. And comparing the magnetic flux density monitored in real time with a dynamic threshold value, generating a deviation signal and judging the state of the magnetic core. Once it is confirmed that the magnetic core is in a non-linear magnetization state, an adjustment mechanism is triggered immediately, winding current distribution is adjusted to change the magnetic flux path length of the magnetic core, and periodic pulse signals are applied to prevent depth saturation of the magnetic core. In addition, by monitoring the adjusted magnetic core magnetic flux density recovery rate, demagnetization processing parameters and pulse signal strategies are optimized, and continuous and efficient operation of the system is ensured. According to the method, the transient voltage suppression capability and stability of the system are remarkably improved, and the overall performance and reliability are enhanced.

The invention discloses a self-adaptive virtual resistance-inductance ratio-based fault ride-through control method for a network-constructed converter, and belongs to the technical field of power grid fault ride-through. The invention discloses a fault ride-through control method for a network-constructed converter based on a self-adaptive virtual resistance-inductance ratio, and the method comprises the steps: firstly analyzing the influence of the virtual resistance-inductance ratio of virtual impedance on the active and reactive power output characteristics of a network-constructed system; three control targets of fault voltage support, current peak limit and system synchronous stability are considered to construct a value constraint boundary of the virtual resistance-inductance ratio of the grid-forming type converter on a virtual impedance plane, and a dynamic selection method of the virtual resistance-inductance ratio is provided in the safety boundary; and selecting an optimal virtual resistance-inductance ratio according to different voltage drop scenes so as to realize collaborative optimization of three control targets. And finally, according to the calculated optimal adaptive virtual resistance-inductance ratio, adjusting a virtual impedance value and putting the virtual impedance value into a control loop so as to limit the short-circuit current during the fault period. According to the method provided by the invention, the voltage supporting capability of the network-forming converter in the fault ride-through process is remarkably enhanced.

The utility model provides an equivalent voltage circuit of a double-motor electric drive assembly. The equivalent voltage circuit comprises a first branch circuit and a second branch circuit, the first end of the first branch is connected with the first end of the second branch through a first reactor; the reactance value of the first reactance is determined by the reactance value of a power coupling device between a first motor and a second motor of the double-motor electric drive assembly; the voltage at the two ends of the first branch is determined by the common-mode voltage of the first motor; the voltage at the two ends of the second branch is determined by the common-mode voltage of the second motor; the first branch comprises a plurality of first sub-capacitors, and the capacitance value of each first capacitor is determined by the capacitance value of the first bearing; the second branch comprises a plurality of second sub-capacitors, and the capacitance value of each second capacitor is determined by the capacitance value of the second bearing; the first motor is connected with the wheels through a plurality of first bearings; the second motor is connected with the wheels through a plurality of second bearings. According to the equivalent voltage circuit of the double-motor electric drive assembly, the technical problem that the double-motor electric drive assembly is not provided with an equivalent voltage circuit can be solved.

An impedance matching circuit for a plasma process supply system and a plasma process system, configured for powers≥500 W and frequencies in a range from 2 MHz to 100 MHz, the impedance matching circuit including a matching unit having one or more reactances and a resonator. The impedance matching circuit is configured for operation at a predetermined high frequency (HF) power signal with a predetermined basic frequency and auto-frequency tuning (AFT) bandwidth, limited by a predetermined upper AFT frequency and a predetermined lower AFT frequency. The resonator is configured to not influence the HF power signal at the predetermined basic frequency and to damp the HF power signal and / or influence the HF power signal in a phase at both the predetermined upper and lower AFT frequencies.

The application discloses a variable frequency operation transformer device, which comprises a base frame, a first transformer module, a second transformer module, a reactance module and a switching conversion module; the first transformer winding comprises a first winding unit, a second winding unit and a first switching unit, the first switching unit is connected with the first winding unit and the second winding unit respectively, the first switching unit has at least a first working state and a second working state, the second transformer winding is coupled with the first transformer winding, the second transformer winding comprises a third winding unit, a fourth winding unit and a second switching unit, the second switching unit is connected with the third winding unit and the fourth winding unit respectively, the second switching unit has at least a third working state and a fourth working state, the switching conversion unit is connected with the reactor and the second transformer winding respectively, and the switching conversion unit has at least a fifth working state and a sixth working state; the design is convenient to construct and maintain, saves the occupied area and reduces the construction and maintenance cost.

The present disclosure relates to the technical field of transformer equipment, and specifically provides an inductor structure, a reactance device, and a transformer device. The inductor structure includes: a first magnetic core having a first end and a second end opposite to each other; and a winding including a first conductor and a second conductor, wherein one end of the first conductor is connected to the first end of the first magnetic core, one end of the second conductor is connected to the second end of the first magnetic core, and the first conductor and / or the second conductor are wound around the outer surface of the first magnetic core; the other ends of the first conductor and the second conductor form the connection terminals of the inductor structure. The disclosed inductor structure effectively suppresses eddy currents in the magnetic core and reduces heating of the magnetic core.

The utility model provides a permanent magnet motor reactance parameter testing device based on a voltage integration method, which comprises a test board, a vertical plate is fixed at the top of the test board through bolts, a retractable assembly is arranged at the top of the vertical plate, a hydraulic rod is fixedly mounted on the outer wall of one side of the vertical plate, and the telescopic end of the hydraulic rod is fixedly connected with two connecting lugs. The opposite sides of the two connecting lugs are rotationally connected with pulleys, a pull rope is wound around the outer wall of the rotating shaft, one end of the pull rope is fixedly connected with the rotating shaft, the other end of the pull rope is connected with a hoisting assembly, the pull rope is movably matched with the outer wall of the pulley, the winding and unwinding assembly comprises a support and a motor, the support is fixed to the top of the vertical plate through bolts, and the inner wall of the support is rotationally connected with the rotating shaft. According to the utility model, the permanent magnet motor can be hoisted and moved to the top of the testboard through the cooperation of the retractable assembly and the hydraulic rod, so that the difficulty of manual carrying is reduced, and the use convenience of the device is improved.

A matching device disclosed herein comprises a plurality of reactance elements, a plurality of relays, a ground element, and an inductor element. The plurality of reactance elements are connected to a high frequency supply line for high frequency power for plasma generation. The plurality of relays include a relay coil and a relay switch each having a first contact connected to each of the plurality of reactance elements. A second contact different from the first contacts of some relay switches among the plurality of relay switches is connected to the ground element. A third contact different from the first contacts of the remaining relay switches among the plurality of relay switches is connected to the inductor element and is connected to the high frequency supply line. The plurality of reactance elements include a lower electrode, a dielectric plate, a plurality of first upper electrodes, and a plurality of second upper electrodes.

The utility model belongs to the field of high-voltage switch temperature rise tests, and discloses a current regulating system for a high-voltage switch temperature rise test, a power supply device is sequentially connected with a voltage regulator, a reactance load unit and a current booster, the other end of the current booster is connected with a high-voltage switch to be tested, and two ends of the reactance load unit are connected with a short-circuit switch in parallel; due to the introduction of the reactance load unit, the total load of the system is increased when the load is small, the regulation of the voltage regulator is more stable, the output current of the large current generator is closer to the designed operation point, and the stability of the test current is obviously improved; when large current output is needed, the short circuit switch can bypass the reactance load unit to reduce the total impedance of the system, and the system can still keep efficient output. According to the system, through dynamic access or short circuit of the reactance load, the effective regulation range of the voltage regulator is expanded, the current regulation speed is reduced by utilizing the characteristics of the inductance load, stable current output is realized, the test precision is improved, good adaptability and controllability are achieved, and the temperature rise test requirements of switch equipment with different capacities are met.

The invention relates to an equivalent uplink and downlink current ratio fault distance measurement method combined with a segmented reactance table, and the method employs an uplink and downlink current ratio method combined with the segmented reactance table to replace a common reactance ratio method and a common uplink and downlink current ratio method in a current complex line direct supply operation mode for fault distance measurement. The multi-line direct supply traction network is divided into a plurality of sections according to different unit impedance, then the reactance value of each section is calculated according to the impedance and mutual impedance of each section, the method not only can consider the influence of an anti-thunder coil and a power supply line on the distance measurement result, but also can ensure the distance measurement precision when the number of stations is large, and the method is suitable for large-scale popularization and application. The distance measurement error is controlled within the range of 250 meters; maintenance personnel are ensured to quickly find out fault points, timely process faults and recover normal operation of lines, and the method is very important for safe, reliable and efficient transportation of a railway system.

Fault location determination in a power transmission system is described. Samples of voltage and current measured are obtained for each phase at a terminal. A first equivalent reactance value based on the samples of voltage and current is calculated. Further, based on the calculated equivalent reactance value a first fault location is determined.

The application discloses a parameter setting method, device and system for a swing reactance of an excitation regulator, wherein the parameter setting method adds forced oscillation to a speed regulator link in a closed-loop simulation test environment, so as to stimulate equal-amplitude oscillation of mechanical power and unit frequency in a set frequency range; the error between a real signal value output by a real excitation device and a simulation signal value output by a simulation test model is calculated, the initial value of the swing reactance parameter is selected according to the error, the adaptability and effectiveness of the swing reactance are verified based on the initial value, the test result is obtained through a voltage step test under a set working condition, and the swing reactance parameter is modified according to the test result, so that the active power fluctuation when the PSS is put into operation meets the set condition. The parameter setting method provided by the application can reduce the risk of power oscillation accidents caused by large unit speed calculation error due to unreasonable swing reactance parameter setting and weak damping or even negative damping of the PSS.

1. The name of this design product: Reactance voltage divider assembly. 2. Purpose of this design product: used for high-voltage electrical testing. 3. The key point of the design of this product lies in its shape. 4. The picture or photo that best illustrates the design points: three-dimensional picture.

The present application relates to a kind of oil-immersed reactance type tap changer, wherein drive mechanism includes conversion index plate, conversion mechanism includes insulated shaft and conversion frame body, and the rotation of conversion index plate is driven by insulated shaft, and conversion frame body is driven to rotate;Conversion frame body includes movable contact disc A, conversion insulating disc and movable contact disc B, wherein first movable contact and second movable contact are respectively arranged on conversion insulating disc and electrically connected with movable contact disc A and movable contact disc B;Antenna static contact A that is always in contact with movable contact disc A is arranged on the upper portion of mounting frame, and the lower portion of mounting frame is provided with the static contact B of antenna that is always in contact with movable contact disc B;Multiple tap static contacts are arranged on mounting frame along the circumferential direction, and each tap static contact is respectively connected with corresponding tap on series coil in single-phase reactance type voltage regulator, and the first movable contact and the second movable contact are rotated by conversion insulating disc and are converted with each tap static contact connection.The present application is compact in structure and reliable in gear conversion, and also increases the number of gear conversion.

The concept according to the invention proposes a generator (11) for powering various instruments (35, 44), which provides a desired output characteristic curve without the aid of a control loop. For this purpose, it uses a reactance network (19) which itself has a desired characteristic curve (i.e., intrinsic). This is accomplished by providing various selectable composite resistances in the output branches of the generator (11), which provides different relationships between the output power and the load resistance.

The invention provides an inverter grid-connected system weak power grid tolerance improvement method based on equivalent resistance reactance analysis, and the method aims at solving the problems that an existing conventional stability parameter design method is high in blindness and has no parameter adjustment direction guidance, and improves the tolerance of an inverter grid-connected system weak power grid by introducing an equivalent resistance reactance distribution diagram. The influence distribution condition of system parameters on stability can be visually displayed, and the parameter adjustment direction can be clearly pointed out. The method comprises the following steps: firstly, obtaining a sequence impedance Bode diagram of a grid-connected system unit and an equivalent power grid, and determining a system instability oscillation frequency; calculating the equivalent resistance and equivalent reactance of the overall aggregation impedance of the system, and drawing a distribution diagram under the condition of target parameter change; then, by combining a stable parameter selection method, locking an area where stable parameters are located, and confirming a parameter adjustment direction; and finally verifying the validity of the selected parameters through simulation. The embodiment shows that the method can effectively improve the stability of the inverter grid-connected system in the weak power grid environment, and has remarkable advantages and beneficial effects.

A power amplifier circuit that can be configured with a single circuit module and that can amplify a plurality of signals separated on the time axis with desired input / output power characteristics is provided. [Solution] The power amplifier circuit comprises an outphasing amplifier having a first amplifier that amplifies a first signal having a first phase generated from a signal to be amplified, a second amplifier that amplifies a second signal having a second phase different from the first phase generated from the signal to be amplified, and a Shereigh combiner including a reactance compensation circuit arranged between the output path of the first amplifier and the output path of the second amplifier, and means for adjusting the susceptance value of the reactance compensation circuit in the Shereigh combiner in accordance with the desired input / output power characteristics of the signal to be amplified.

The invention belongs to the field of new energy grid-connected relay protection, and particularly relates to a pilot reactance protection method based on time domain model recognition. Presetting a pilot reactance protection action area according to the inherent impedance and capacitive reactance parameters of the power transmission line; acquiring three-phase current and voltage sampling values at two sides of the power transmission line, synthesizing differential voltage and differential current data, and calculating the variable quantity of two adjacent sampling points of the differential current; whether longitudinal reactance protection is started or not is determined according to the differential current variable quantity, and waveform similarity detection is conducted on currents on the two sides after protection is started; when a waveform similarity detection result is greater than a threshold value, an external fault is judged, and pilot reactance protection is locked; otherwise, establishing an R-L equivalent circuit model equation, performing parameter identification on the short-circuit impedance, and when the vector positions of the pilot resistor and the pilot reactance in the complex plane fall into a preset pilot reactance protection action area, performing pilot reactance protection section entering, and performing pilot reactance protection action after confirmation.

To provide a reactance compensation circuit capable of eliminating matching deviation based on the influence of the output capacity of a semiconductor switch as much as possible.SOLUTION: The phase shift amount control circuit 65 outputs a control signal for controlling the phase shift amount based on the capacitor voltage VCB. The variable phase shift circuit 62 shifts the phase based on the control signal. The bridge circuit 63c is driven by the drive signal shifted by the variable phase shift circuit 62, and the voltage outputted from the bridge circuit 63c is controlled to have a predetermined difference in phase from the voltage on the side of the power transmission source with respect to the bridge circuit 63c.SELECTED DRAWING: Figure 2

The present disclosure relates to a method for controlling a distance protection system, as well as a respective device and system for performing the method. Measurements are received. The measurements comprise current and / or voltage measurements at a first position along a transmission line for an electrical power system. A first impedance is computed from the received measurements. A fault location is determined from the computed first impedance and a first impedance boundary. Responsive to the determined fault location, a second impedance is computed. The fault location is redetermined from the computed second impedance and the first impedance boundary. The distance protection system is controlled based on the determined fault location or the re-determined fault location.

The invention provides a method for accurately calculating the leakage reactance of a transformer, and the method comprises the steps: obtaining a calculation formula of the primary side leakage reactance and the secondary side leakage reactance of the transformer through formula derivation according to a quantitative relation that the leakage reactance of the transformer is directly proportional to the square of the number of turns of a winding; the direct proportion quantitative relation between the leakage reactance of the transformer and the square of the number of turns of the winding is obtained according to a calculation formula, and the leakage reactance values of the on-load tap-changer of the transformer under different gears can be accurately calculated by combining the relation between winding parameters and gear adjustment of the on-load tap-changer. After the technical scheme of the invention is adopted, the accuracy and practicability of leakage reactance calculation of the transformer can be improved, the load distribution of the transformer can be more reasonable by accurately calculating the leakage reactance values of the primary side and the secondary side of different gears, and the calculation precision of voltage regulation of the transformer is improved.

The application relates to the technical field of adjusting devices, and discloses a self-adaptive reactance adjusting device for a variable current voltage regulator, which comprises a screw cap, a containing cavity arranged in the screw cap, and a rotating rod, the screw cap is sleeved on the outer surface of the rotating rod and can rotate with the central axis of the rotating rod as the rotation center, and the rotating rod is arranged to rotate simultaneously with the rotating rod when the screw cap rotates. When the semicircular ring can move along the diameter direction, the friction block can be driven to move along the diameter direction of the semicircular ring, the friction block is driven to move close to or away from the friction ring by the semicircular ring, the force of the friction block abutting against the friction ring is increased or decreased, the size of the friction force during movement is changed, the operator can know that the generated friction resistance is different under different gear positions, the operator can notice the adjusting range and proportion, the operator can be prevented from making mistakes, and it is ensured that no error occurs in subsequent reactance adjustment.

The invention discloses a capacitive reactance detection circuit and method and a battery management system, and the circuit comprises a constant current source sub-circuit which is used for providing a constant current power supply; the output end of the push-pull sub-circuit is connected with the input end of the constant current source sub-circuit, and the push-pull sub-circuit is used for performing boost control on the constant current source sub-circuit; the capacitive reactance detection sub-circuit comprises a first switch, a second switch, a first capacitor and a second capacitor, the output end of the constant current source sub-circuit is connected with the input end of the first switch and the input end of the second switch, the output end of the first switch serves as the output end of a direct current positive bus, and the output end of the second switch serves as the output end of a direct current negative bus. One end of the first capacitor is connected with the direct-current positive bus, one end of the second capacitor is connected with the direct-current negative bus, and the other end of the first capacitor and the other end of the second capacitor are connected and simultaneously connected with the electric chassis; and the voltage division sub-circuit is connected between the output end of the constant current source sub-circuit and the input end of the first switch and is used for detecting the voltage change in the charging process of the first capacitor and the second capacitor.

The embodiment of the application discloses a kind of load tap changer and adaptive reactance of current transformer coordinated control method, device and storage medium, method includes: the load tap changer of current transformer is with adaptive reactor and forms joint control unit, obtains the transient security index of each joint control unit;Exchange the transient security index between adjacent converter station, and based on transient security index, combined with electrical coupling relationship, collaborative generation is used to characterize commutation instability state system-level operation forbidden zone description, form collaborative security constraint quantity;According to collaborative security constraint quantity and system-level operation forbidden zone, determine security condition;When collaborative security constraint quantity meets security condition, only by continuously adjusting the reactance value of adaptive reactor to AC side voltage and current are quickly adjusted;When collaborative security constraint quantity does not meet security condition, trigger load tap changer to execute gear switching.The application significantly improves the transient stability of multi-terminal high-voltage direct current system.

The embodiment of the invention discloses a cooperative control method and device for on-load tap-changer and adaptive reactance of a variable-current voltage regulator and a storage medium, and the method comprises the steps: enabling an on-load tap-changer and an adaptive reactor of the variable-current voltage regulator to form a combined control unit, and obtaining a transient safety index of each combined control unit; exchanging transient safety indexes between adjacent converter stations, and cooperatively generating a system-level operation forbidden area description used for representing a commutation instability state based on the transient safety indexes and in combination with an electrical coupling relationship to form a cooperative safety constraint quantity; determining a safety condition according to the collaborative safety constraint quantity and the system-level operation forbidden area; when the collaborative safety constraint quantity meets the safety condition, the voltage and current of the alternating current side are quickly adjusted only by continuously adjusting the reactance value of the self-adaptive reactor; and when the collaborative safety constraint quantity does not meet the safety condition, triggering the on-load tap-changer to execute gear switching. According to the invention, the transient stability of the multi-terminal high-voltage direct-current system is remarkably improved.

The invention discloses a station control method, device, equipment, medium and product, and relates to the technical field of power system operation control, the method comprises the following steps: determining a system topological graph of a to-be-controlled station, and determining a virtual power angle vector relationship of the to-be-controlled station based on the system topological graph; determining the initial equivalent reactance of the to-be-controlled station, and updating the initial equivalent reactance according to the virtual power angle vector relation, the outgoing line current of the to-be-controlled station and the high-voltage side bus voltage to obtain standby equivalent reactance; and processing the initial equivalent reactance and the standby equivalent reactance by using a preset reactance evaluation rule to obtain a target equivalent reactance of the to-be-controlled station, and controlling the to-be-controlled station to operate based on the target equivalent reactance. The station control method does not need to depend on additional station equipment, is low in use limitation and high in popularization degree, and can increase the damping level of the whole station at low cost.

Fault location determination in a power transmission system is described. Samples of voltage and current measured are obtained for each phase at a terminal. A first equivalent reactance value based on the samples of voltage and current is calculated. Further, based on the calculated equivalent reactance value a first fault location is determined.

The invention discloses a reactance optimization credible capacity blocking relieving method, system and equipment and a medium, and the method comprises the steps: building a power grid impedance matrix and a power transfer distribution factor matrix, and defining a line fault distribution factor index to quantify a power flow transfer risk after a fault; a key line with unbalanced reactance and capacity distribution is accurately identified by using classification thresholds of credible capacity and line thermal capacity; based on a mixed integer linear programming model, line impedance distribution is optimized by dynamically adjusting fixed reactance, and the credible capacity of the line is improved; according to the method, through structural analysis and parameter collaborative optimization, in Monte Carlo simulation, feasible power generation plans are remarkably increased, the power generation disturbance variable is greatly reduced, the safety margin and economy of the power grid are remarkably improved, and the method is suitable for a modern power grid blocking management scene with high-proportion renewable energy access.

The invention discloses a generalized parallel EF type power amplifier based on output end active third harmonic injection, a main power amplifier is connected with an auxiliary power amplifier through an inductance-capacitance third harmonic resonance circuit, and a second reactor is arranged between the inductance-capacitance third harmonic resonance circuit and the auxiliary power amplifier; a drain electrode of the main power amplifier transistor is connected with a main power amplifier drain electrode power supply through a lambda / 4 transmission line; one end of the main switch is respectively connected with one end of the first capacitor, one end of the first inductor, one end of the lambda / 4 transmission line, one end of the inductance-capacitance third harmonic resonance circuit and one end of the inductance-capacitance resonance circuit; the other end of the lambda / 4 transmission line is connected with a main power amplifier drain electrode power supply; the other end of the inductance-capacitance resonance circuit is connected with one end of an output end load; a first reactor is arranged between the other end of the inductance-capacitance resonance circuit and one end of the output end load; the other end of the main switch is respectively connected with the other end of the first capacitor, the other end of the first ideal blocking capacitor and the other end of the output end load; the first reactance and the second reactance are variable reactance.