278 results about "Limiter" patented technology

The invention discloses a method for improving stability of a network-forming converter by considering voltage and phase transients, which solves the problem of over-current control blind areas existing at the initial stage of a fault and at the moment of clearing in a traditional single current limiting method and overcomes the defect that the stability is sharply deteriorated when a traditional strategy is used for coping with a composite fault. The method comprises the following steps: S1, obtaining a virtual synchronous machine swing equation under a synchronous rotating coordinate system and an equivalent circuit model under the action of a circular current limiter; and S2, obtaining a nonlinear relation between the output power and the power angle of the converter, and analyzing a transient stability domain of the converter during a fault period. And S3, obtaining a mixed current limiting strategy, deducing an equivalent circuit model corresponding to the strategy, and further obtaining an output power expression corresponding to the strategy. And S4, obtaining a power damping term acting on an active power control loop, further obtaining a synchronization stability improvement strategy, and deducing a closed-loop model describing the system at the moment.

The invention discloses a multi-channel audio calibration method, system and device and a storage medium, and relates to the technical field of audio, and the method comprises the steps: collecting and separating a main sound channel signal and a bass sound channel signal in a multi-channel audio signal; detecting time delay between a main sound channel and a bass sound channel based on a phase correlation algorithm, and performing adaptive delay compensation; the state change of the audio signal is monitored in real time, and before or when a signal switching event is detected, gradient gain envelope is applied to the bass sound channel signal, so that the signal amplitude gradually changes to a target value according to a preset nonlinear curve; a sonic boom event is analyzed and identified based on multi-dimensional characteristics, a self-adaptive amplitude limiter with a prospective processing capability is started for suppression, and harmonic distortion compensation and phase correction are carried out on a processed signal, so that the problems of signal asynchronization caused by low-frequency output delay of an audio system in the prior art, and the system reliability is improved are solved. Therefore, the low-frequency sound quality and the system stability are improved.

A telecommunications tray is configured for mounting to a telecommunications fixture. The tray includes a removably mounted telecommunications module that defines a body that is enclosed by a cover to define an interior. The module includes radius limiters within the interior for managing cables and defines connection locations for inputting and / or outputting signals via cables for processing within the module, the telecommunications module movably mounted to the tray.

Apparatus and methods for power amplifier signal limiting are disclosed. In certain embodiments, a front-end system includes a low noise amplifier that amplifies a radio frequency receive signal during a receive frame, a power amplifier that amplifies a radio frequency transmit signal during a transmit frame, and a signal limiter operable to limit a signal power of the power amplifier in an attenuating mode. The signal limiter includes a radio frequency detector configured to generate a detection signal based on detecting a power level of the radio frequency transmit signal, and a latch that locks the signal limiter in the attenuating mode in response to activation of the detection signal. The latch is reset by a bias signal of the power amplifier that is activated during the transmit frame and deactivated during the receive frame.

A mobile terminal protective holder includes a shell body, a supporting plate, a supporting frame, an angle limiter, and a circuit board. Electronic products such as mobile terminals are arranged in an accommodating cavity of the shell body, and the supporting frame is rotatable with the supporting plate around an axis. A Hall switch and a light emitting member are provided on the circuit board. A magnetic member is provided on the supporting plate. When the supporting plate rotates, the magnetic member approaches or moves away from the Hall switch, thereby controlling the connection and disconnection of the Hall switch.

Phase interpolators are provided, the phase interpolators including: a first phase interpolator having a first output that outputs a first interpolated clock signal based on quadrature clock signals and a first phase interpolator control signal; a second phase interpolator having a second output that outputs a second interpolated clock signal based on the quadrature clock signals and a second phase interpolator control signal that is shifted from the first phase interpolator control signal by half of an integral nonlinearity (INL) period of the first phase interpolator; and a phase combiner that outputs a third interpolated clock signal based on the first interpolated clock signal and the second interpolated clock signal. In some of these embodiments, the phase interpolators further comprise a first amplitude limiter that receives the first interpolated clock signal and outputs a first amplitude-limited interpolated clock signal that is provided to the phase combiner.

The invention discloses a turbine generator set power oscillation emergency valve switching control method, system, equipment and medium based on a thermodynamic model, and belongs to the technical field of electric power system automation control and thermal energy power engineering, and the method comprises the steps: monitoring the operation state of a set in real time, and collecting the current data of the set; calculating a theoretical balance valve position required for maintaining the current target power in real time by using the corrected inverse thermodynamic model; and the power fluctuation condition is monitored in real time, when it is detected that power oscillation happens to a unit and valve cutting logic is triggered, the system intercepts a conventional feedback instruction for tracking the actual valve position, the theoretical balance valve position is directly used as a target instruction, and a control valve is forcibly driven to act to the valve position through a rate limiter. According to the method, it can be ensured that after closed-loop control of the unit is cut off, the valve rapidly returns to the physical balance opening degree matched with the current load, an oscillation source is effectively eliminated, severe fluctuation of main steam pressure and temperature is stabilized, and the safety and stability of the unit under the abnormal working condition are remarkably improved.

The invention discloses an enhanced transient stability improvement strategy and system for a grid-forming converter based on current amplitude limiting, and aims to effectively suppress a power angle instability phenomenon in a power grid fault or transient period and ensure that the converter has higher stability in a grid-connected process. The specific implementation comprises a dynamic dq-axis current amplitude limiting control strategy and a reference power control structure. Three-phase voltage and current of a grid-connected point of the converter are measured in real time, and a dq-axis current reference value and a power ring reference value are dynamically adjusted by combining a power angle and angular velocity deviation in an active power link, so that power angle instability during a transient period is accurately inhibited. According to the control strategy, the risks of overcurrent and system instability are effectively reduced, and particularly when a power grid breaks down or is in a normal condition, quick response and stable output of the system are ensured by switching the control modes in real time.

The application discloses a container ship valve body casting device with intelligent temperature control function and relates to the technical field of valve body casting devices. The container ship valve body casting device comprises a support, an electric sling, a moving beam, a pouring bag, a pouring table, a sliding frame and a hot-driven double-trip isolation curtain. The first and second limiters are alternately matched, so that the driving head reciprocates between the initial end and the end of the curved groove, and the cooling device is automatically started and stopped according to the pressure sensor signal, thereby realizing double-trip scraping of the isolation bevel and continuous collection of metal particles. The splashed metal liquid forms an oxide film in the air, the rough surface of the isolation bevel is bitten by the oxide film through surface depression, so that the splashed metal liquid can reliably adhere to the isolation bevel, thereby effectively reducing the risk of continuous splashing and diffusion. Part of the metal liquid adhering to the isolation bevel rolls downward along the bevel under the action of gravity and finally enters the collection groove, thereby realizing effective guidance and centralized collection of the splashed metal liquid.

This specification provides a rate limiting method, apparatus, electronic device, and medium for a distributed cluster. The method includes: if at least one token in the token set is greater than 0, calculating a token deviation value; if the token deviation value is less than a first threshold and the condition that all tokens in the token set are greater than or equal to 0 is not met, reducing the token generation rate corresponding to the token bucket rate limiter with tokens greater than the token number threshold, and increasing the token generation rate corresponding to the token bucket rate limiter with tokens less than the token number threshold; if every token in the token set is less than or equal to 0, calculating a rate deviation value based on the generation rate set; if the rate deviation value is greater than or equal to a second threshold, reducing the token generation rate corresponding to the token bucket rate limiter with a token generation rate greater than the token generation rate threshold, and increasing the token generation rate corresponding to the token bucket rate limiter with a token generation rate less than the token generation rate threshold.

A control circuit for an audio amplifier includes a reference voltage generator and a voltage limiter. The reference voltage generator generates a first reference voltage and a second reference voltage based on a supply voltage of the audio amplifier. The voltage limiter receives an audio input signal, the first reference voltage, and the second reference voltage, and generates an adjusted audio signal based on the audio input signal, the first reference voltage, and the second reference voltage. When a voltage level of the audio input signal is higher than the first reference voltage, the adjusted audio signal is limited to the first reference voltage, and when the voltage level of the audio input signal is lower than the second reference voltage, the audio input signal is limited to the second reference voltage. The input voltage limiter is used to generate a truncated input signal proportional to the desired output signal when clipping occurs. This prevents the control loop from being affected by inaccurate feedback information and enables faster transient response and less distortion.

A distributed ice melting device topological structure suitable for an ultra-high voltage power transmission line comprises a plurality of ice melting sub-modules arranged in a distributed mode, and each ice melting sub-module comprises a single-turn coupling transformer, a metal oxide voltage limiter, a bypass switch, a filter, an H-bridge current converter and a direct-current capacitor. A primary winding of the single-turn coupling transformer is directly formed by split sub-conductors of the ultra-high voltage power transmission line, and a secondary winding of the single-turn coupling transformer is electrically connected with other parts of the ice melting sub-modules, so that the ice melting sub-modules are connected in series on the split sub-conductors of the power transmission line in a distributed manner; the H-bridge current converter is electrically connected with the direct-current capacitor, and the direct-current capacitor provides smooth direct-current voltage for the H-bridge current converter; the filter is connected in series with the H-bridge current converter, the bypass switch is connected in parallel with the H-bridge current converter, and the metal oxide voltage limiter is connected in parallel with the line side output end of the ice melting sub-module; and the ice melting sub-modules adjust the current of the corresponding split sub-conductors by changing the equivalent impedance of the ice melting sub-modules, so that accurate ice melting of the ice-coated split sub-conductors is realized, and the overall current and the transmission power of the power transmission line are kept unchanged. The technical problem to be solved by the invention is to provide the distributed ice melting device topological structure suitable for the ultra-high voltage power transmission line, and the technical problem that the existing ice melting technology cannot realize accurate ice melting and non-power-cut operation on an ice coating section on the ultra-high voltage power transmission line is solved. And normal transmission of the line is affected due to overlarge capacity demand, line overcurrent or incapability of three-phase synchronous ice melting.

This invention relates to a ground-based analog frequency conversion system for satellite payloads and its implementation method. The system includes: a filtering and coupling module for receiving high-frequency signals in the Q and V bands and splitting them into a coupling signal and a main signal, which are then transmitted to a detector module and a limiter, respectively. The detector module detects the power of the coupling signal at different temperatures and feeds it back to the control module. The limiter limits the maximum strength of the main signal to protect the low-noise amplifier (LNO). The LNO amplifies the main signal and reduces noise. A phase-locked loop (PLL) and frequency conversion module down-converts the high-frequency signal to an intermediate-frequency (IF) signal. An IF filtering and amplification module suppresses spurious interference and amplifies the IF signal. A temperature compensation module and a gain control module adjust the attenuation value to achieve temperature compensation and ensure that the IF output signal strength meets preset requirements. All modules are integrated using micro-assembly technology. This system can reduce the power consumption and cost of satellite launch and communication.

The present application provides a kind of refuse generator unit primary frequency modulation control method and device, method includes the following steps: collecting actual frequency and rated frequency of power grid, judge refuse generator unit primary frequency modulation system state;Through refuse generator unit operating data, refuse generator unit primary frequency modulation system parameter is identified;Based on frequency deviation, get the opening degree instruction of regulating valve;According to the state of refuse generator unit primary frequency modulation system, based on state observer and control law, get the opening degree of oil motor;The actual value of oil motor opening degree is through limiter, and the opening degree of regulating valve is obtained;Complete refuse generator unit primary frequency modulation control.The present application can provide control algorithm support for the optimization of refuse generator unit primary frequency modulation, and provide support for the frequency regulation of refuse generator unit supporting power grid.

1. The name of the design product: wireless limiter. 2. The use of the design product: the safety device for limiting the movement range of machinery or equipment. 3. The design points of the design product: the shape of the design product. 4. The picture or photo that best indicates the design points: combination state figure 1.

The invention discloses a P-band high-power filtering and amplitude limiting assembly, which belongs to the technical field of microwaves and comprises a filter, an amplitude limiter, a polarizer, a coupler and a metal cavity. The amplitude limiter is installed on the bottom layer of the metal cavity, the filter and the polarizer are installed on the top layer of the metal cavity, the coupler is installed on the side wall of the metal cavity, the filter, the low-pass filter and the polarizer are connected in a wall-penetrating welding mode through a 50-ohm metal connecting rod, and the polarizer is fixed to the metal cavity through a medium supporting column. The whole assembly belongs to an upper-lower layer structure. According to the assembly, the transmission path between devices is shortened, the emission loss of the assembly is reduced, the size of the filtering and amplitude limiting assembly is greatly reduced under the condition that composite multiple functions are met, and the purposes of high power and high integration are achieved.

The application relates to an electromagnetic operating mechanism with a breaking middle section buffer, which is used in a high-voltage vacuum circuit breaker, a moving guide rod extends into a frame from one end of the frame, the moving guide rod and the frame are in sliding connection, a repulsion disc is fixedly connected with the moving guide rod and is located in the frame, a closing limiter is fixed in the frame, the closing limiter is sleeved outside the moving guide rod and is located above the repulsion disc, a breaking limiter is fixed in the frame and is located below the repulsion disc, a breaking repulsion coil is installed in the frame and is sleeved outside the breaking limiter, and a middle section buffer coil is fixed on a side wall of the frame and is located in a movement area of a breaking middle section of the moving guide rod. The application also relates to a use method of the electromagnetic operating mechanism with the breaking middle section buffer. The application realizes the movement characteristics of the breaking middle section deceleration and later acceleration of a moving contact in a breaking process of the circuit breaker and belongs to the technical field of high-voltage circuit breakers.

An illustrative example embodiment of a buck-boost converter includes at least three input / output ports, at least three switch sets, and at least two ripple current limiters. One switch set is associated with each input / output port. Each ripple current limiter is associated with a corresponding switch set within the switch sets, and each ripple current limiter is located between the associated switch set and the other switch set.

A microneedle patch applicator device (1) comprises a plunger (2) having a distal microneedle patch abutting surface (19) and a receiver (3) for the plunger. The plunger is configured for reciprocal linear movement relative to the receiver between an extended configuration in which the distal microneedle patch abutting surface is spaced from the receiver and a depressed configuration. The receiver comprises a force limiter associated with the plunger configured to prevent movement of the plunger from the extended configuration to the depressed configuration until a pre-determined threshold input force has been applied to the plunger by the user.

The invention relates to a net holder (1) for a play net (23), comprising: an inner post (3) with a net mounting portion (19) designed for insertion into a net loop (24) of the play net (23), and a spindle (12) with an external thread; an at least substantially L-shaped body (2) with an outer post (5) and a cross bar (6), the outer post (5) being designed as a hollow box profile for receiving and guiding the inner post (3) and having a slot-shaped net passage (7), the cross bar (6) having at a free end a fastener for fastening to a playing table; and an adjuster (4) formed as a sleeve having an internal thread configured for engagement with the external thread of the spindle (12), wherein a retainer is provided for retaining the adjuster (4) with respect to a longitudinal position relative to the outer post (5) but allowing rotation of the adjuster (4); wherein at least one of the inner post (3) and the outer post (5) comprises a limiter for limiting a rotation of the inner post (3) in the outer post (5), which however allows a longitudinal displacement.

The half-bridge LLC circuit comprises an LC filter circuit, an MOS tube bridge arm, a capacitor bridge arm, a resonant inductor Lr, a transformer, a diode D1, a diode D2, a diode D3, a diode D4, a filter capacitor Co, a resistor RL, a compensator, an amplitude limiter, a voltage-controlled oscillator, a PWM controller, an isolation driver, a comparator and a PI controller. According to the invention, the problems of loss, electromagnetic interference and the like caused by improvement of the switching frequency of the existing hard switching circuits such as forward and half-bridge circuits in the space navigation secondary power supply system are solved.

The utility model discloses a kind of electric heat tracing band current limiter components, comprising: current limiter body, bottom shell, cover, current limiter body is fixedly installed in bottom shell cavity, the peripheral edge of cover bottom surface can be attached on the peripheral edge of bottom shell top surface to form the shell that current limiter body is contained closed therein, current limiter body includes multiple terminal blocks, bottom shell is connected with the threading pipe that the cable diameter is adapted to cable from shell outside is passed into to the shell inside, multiple wires in cable are bundled, which can be connected with terminal block, by encapsulating the terminal block of current limiter body in shell, the combustible and explosive gas or dust of outside can be isolated to enter shell and contact the terminal block that possible discharge occurs, so that electric heat tracing band current limiter component has explosion-proof performance.

The invention relates to a method for controlling an electric machine, the method comprising the following steps: detecting a predetermined operating state of the electric machine while performing traction control of the electric machine; performing transition control and / or monitoring upon detection of the predetermined operating state in order to subsequently switch an active short circuit of the electric machine, comprising the following steps: generating steady-state target current values ​​to produce an active short circuit based on current input variables of the electric machine; performing rate limiting to limit the maximum rate of change of the target current values;Implementation of a feedforward control process in which the target current values ​​output by the rate limiter are converted into target voltage values, which contain at least one component from a time-dependent change in the magnetic flux of the electric machine, and output for controlling the electric machine; switching the active short circuit of the electric machine. Furthermore, the invention relates to a corresponding control device, a corresponding computer program and a corresponding storage medium.

The application provides a limiter circuit, which comprises a plurality of transmission lines connected in series, one end of the transmission lines is used as an input end of a radio frequency signal, the other end of the transmission lines is connected with an input end of an amplifier, and an output end of the amplifier is used as an output end of the radio frequency signal; a limiter branch is connected between adjacent transmission lines and the amplifier in sequence, and the parasitic capacitance of each limiter branch is equal; a limiter bias circuit is electrically connected with each limiter branch, and is used for making the opening power voltage of each limiter branch equal. According to the application, the size of each limiter branch is adjusted according to the uneven distribution of current, so that the current density of each limiter branch is balanced, and the insertion loss and impedance matching can be effectively improved, and the bandwidth is improved under the premise of realizing the current density balance and improving the power protection ability.

A non-volatile memory device (1) includes a memory element (4) that can perform a program operation, a switch (9) having its first terminal connected to an application terminal for a first supply voltage (VDD), an even number of inverters (5, 6) of which input side is connected to a first node (N1) to which the second terminal of the switch and the memory element are connected, and a current limiter (8) that limits the current flowing through the path via the application terminal for the first supply voltage, the transistor, and the memory element when a high-side transistor (61) included in the final-stage inverter (6) arranged in the final stage in the even number of inverters is on.

The application discloses a current-limiting and energy-reducing device for a particle beam and a use method thereof. The current-limiting and energy-reducing device comprises a vacuum cavity, a current limiter and a plurality of energy reducers, and the current limiter and the energy reducers are arranged in parallel in the vacuum cavity. Two energy-reducing blocks with adjustable positions are arranged in each energy reducer, each energy-reducing block is in a wedge-shaped plate structure, the two energy-reducing blocks are arranged in parallel and move relatively during the adjustment process. The use method is that the current limiter and the energy reducers are independently operated, when only the flow intensity needs to be adjusted, the current limiter is adjusted to the required position, when only the energy needs to be adjusted, the energy reducers are adjusted or a single energy reducer is selectively adjusted, the thickness of each energy-reducing block through which the beam passes is added to reach the thickness value of the required energy-reducing material, and when the flow intensity and the energy need to be adjusted simultaneously, the current limiter and the energy reducers are adjusted simultaneously, so that the beam passes through the current limiter and the energy reducers in sequence. In the application, the thickness of the energy reducer is continuously adjustable, and the application is flexible and convenient.

The invention provides a metal flow limiter with a pore plate structure and a rapid design method thereof, and the method comprises the steps: carrying out the flow-pressure difference test of a metal flow limiter without a superposed pore plate, fitting the test data into a flow velocity-original pressure difference relation curve, building a metal flow limiter fluid simulation model, and carrying out the finite element mesh division. The method comprises the following steps: setting fluid medium parameters, defining porous medium attributes, carrying out analogue simulation, repeating the previous steps on a metal flow limiter of a superposed pore plate, obtaining a corresponding data relationship between the pore diameter of the pore plate and the total pressure difference under fixed flow, defining an insufficient development factor theta to obtain a relational expression between the pore diameter and the insufficient development factor, and finally obtaining a relational expression including the flow, the total pressure difference and the pore diameter of the pore plate. The problems that in the prior art, a calculation model fails, design efficiency is low, and adaptability is poor are solved, the pore plate and the sintered filter element are combined to adapt to a wide flow range, the method is suitable for high-purity and high-pressure fluid flow limiting scenes, and remarkable economic and technical benefits are achieved.

The invention relates to the technical field of radio frequency devices, in particular to an amplitude limiter circuit structure integrated with a filtering function by a gallium arsenide process, and the circuit sequentially comprises a 50-ohm microstrip input matching section, a first-stage amplitude limiting filtering unit, a second-stage amplitude limiting filtering unit and an output matching section along a main transmission line, in the first stage, three forward PIN diodes and three reverse PIN diodes are stacked and connected to a main circuit in parallel, high power tolerance and symmetrical amplitude limiting capacity are achieved, and two low-frequency transmission zero points are formed by fusing a micro-strip grounding branch knot and an MIM capacitor resonator; in the second stage, two anti-parallel PIN diodes are matched with a grounding inductor to form a third transmission zero point, three groups of resonant structures are integrated, six transmission zero points are introduced, the filtering performance in a 12-18GHz frequency band is remarkably enhanced, a PIN diode parasitic capacitor and a microstrip inductive structure are skillfully utilized by the circuit to cooperatively realize filtering, extra passive elements are not needed, and the cost is low. The method is suitable for integrated protection of sensitive devices in a high-frequency radar and communication system.

The utility model discloses a kind of multistage electrostatic and overload protection circuit of IOT receiving LNA, belong to internet of things technical field, comprising: setting radio frequency signal main link, high pass filter, amplitude limiter and coupler are connected in series on it;The input end of radio frequency switch is connected with coupler, its first output end connects LNA, second output end connects bypass channel;Dynamic control loop monitors the signal power of main link in real time through coupler, when power is over-limit, the micro control unit in this loop will output control signal, on the one hand drive radio frequency switch switch signal from LNA channel to bypass channel, on the other hand simultaneously shut off the power supply of LNA.The utility model realizes quick, comprehensive overload protection to LNA by the double synergistic action of signal channel switching and power off, and combines the innovative π type ESD protection network, under the premise of not affecting signal quality, greatly improve the reliability of IOT equipment in complex electromagnetic environment.

The invention discloses a transient stability margin evaluation method for a grid-forming type permanent magnet wind power system considering current saturation, and the method comprises the steps: obtaining an implicit expression of a current-limiting trigger angle through the instantaneous variation of the active power transmission limit of the system caused by the triggering of a current limiter, and solving the current-limiting trigger angle; when a three-phase symmetric short-circuit fault occurs in a power grid, a transient stability margin evaluation index gamma of the grid-forming type permanent magnet direct-drive wind power system considering current saturation is defined, the gamma value is calculated in real time, and the transient stability and the transient stability margin of the grid-forming type permanent magnet direct-drive wind power system are judged and evaluated according to the gamma value during the three-phase symmetric short-circuit fault of the power grid. According to the method, the transient stability margin and influence factors of the grid construction type permanent magnet direct-driven wind power system adopting direct current capacitance synchronization during the three-phase symmetric short-circuit fault period of the power grid can be reflected, whether the transient synchronization of the system is stable or not under the current saturation working condition can be visually judged, and the power angle instability risk of the new energy grid-connected system can be reduced.