1026 results about "Limiter" patented technology

The invention discloses a multi-target cooperative fault ride-through method suitable for a network-forming converter, and the method comprises the steps: carrying out the precise amplitude limiting of a fault current through an annular current limiter, and adjusting a power angle to a lower boundary of a transient stability domain during a fault period; and multi-target collaborative optimization of transient synchronous stability, power grid reactive power support and fault current suppression in the fault ride-through process is realized. An optimal power angle set meeting fault ride-through multi-target cooperation in a multi-element fault scene is constructed by performing off-line beforehand rehearsal training on a system physical model; when the power grid breaks down, the network construction type converter carries out online table look-up search based on the trained set, an active power instruction meeting the transient stability and the optimal reactive power support in the current fault scene is calculated, and the supporting capacity of the network construction type converter to the power grid is mined to the maximum extent while the network construction type converter operates safely and stably. According to the method provided by the invention, the network construction operation characteristics of the converter can be maintained under the power grid fault, and the multi-target collaborative fault ride-through capability of equipment is enhanced.

The invention relates to a test device and method for testing the performance of an elevator speed governor, and the device comprises a test rack which is internally provided with a lifting channel for testing; the main rope is hung and wound on the traction machine; the undercarriage is arranged on one side of the traction machine and connected to the main rope, and the car frame is arranged below the undercarriage and connected with the undercarriage through a detacher; the counterweight frame is arranged on the other side of the traction machine and is connected to the main rope; the speed limiter is arranged at the top of the test rack; the rope gripper is arranged at the top of the test rack; and the data acquisition unit is used for acquiring the running speed of the lift car frame, the wheel speed of the speed limiter, the lifting force of the speed limiting rope, an electrical action signal and a mechanical action signal. The performance of the speed governor can be tested under the working conditions that the lift car frame freely falls when running at a rated speed and the lift car frame falls downwards at different accelerations in a static state.

The invention discloses a state evaluation and fault early warning method and system based on superconducting current limiter modeling, an electromagnetic heat multi-physical field coupling model of a superconducting current limiter is constructed based on finite element software, and the method comprises the following steps: constructing a three-dimensional geometric structure of a solenoid-shaped superconducting current limiter, and setting a peripheral electromagnetic environment boundary; establishing an electromagnetic field control equation based on a Maxwell equation set and the nonlinear resistivity characteristic of the superconducting material, and coupling a solid heat transfer control equation to form a multi-physical field interaction model; optimizing grid division to balance calculation precision and solving efficiency; body parameters of the superconducting current limiter including the initial critical current Ic0 and the critical temperature Tc and working condition parameters including the environment temperature and the transmission current It are input, the parameters are dynamically adjusted according to the actual operation scene, and the voltage U at the two ends during normal operation is calculated through a model; by collecting voltage measured values Up at the two ends of the superconducting current limiter during actual operation in real time, whether the voltage measured values Up exceed a threshold value set according to the voltage U or not is judged, and an early warning mechanism is triggered.

A telecommunications tray (50 / 300 / 400 / 600 / 900 / 1100 / 1200 / 1400 / 1800) is configured for mounting to a telecommunications fixture. The tray (50) includes a removably mounted telecommunications module (100 / 200 / 302 / 402 / 700 / 800 / 1000 / 1100 / 1300 / 1900 / 2000) that defines a body that is enclosed by a cover (1102 / 1320 / 1924) to define an interior. The module (100 / 200 / 302 / 402 / 700 / 800 / 1000 / 1100 / 1300 / 1900 / 2000) includes radius limiters (902 / 1356 / 1358 / 1954) within the interior for managing cables and defines connection locations for inputting and / or outputting signals via cables for processing within the module (100 / 200 / 302 / 402 / 700 / 800 / 1000 / 1100 / 1300 / 1900 / 2000), the telecommunications module (100 / 200 / 302 / 402 / 700 / 800 / 1000 / 1100 / 1300 / 1900 / 2000) movably mounted to the tray (50 / 300 / 400 / 600 / 900 / 1100 / 1200 / 1400 / 1800).

Aspects of the subject disclosure may include, for example, an inner clock generation circuit, including: a selectable frequency divider having: a ring of tri-state inverters; a reset gate on an output of each tri-state inverter in the ring; and a reset circuit comprising one or more selectable flip-flops; and a duty-cycle limiter that generates clock signals having a 25% duty cycle from three out of four quadrature clock signals. Other embodiments are disclosed.

A control device includes a modulation rate calculator configured to calculate a modulation rate based on a DC voltage on a DC side an, a limiter configured to update a DC voltage command lower bound limiter based on the lower bound limiter operation value; a maximum power point tracking controller configured to calculate a first DC voltage command value and determine a second DC voltage command value based on the calculated first DC voltage command value and the DC voltage command lower bound limiter set to the limiter, and an inverter controller configured to control an inverter of the power conversion system based on the second DC voltage command value.

The invention relates to the technical field of servo motor control, and particularly discloses an intelligent control system and method for a servo motor, and the method comprises the steps: collecting the position, speed, current and acceleration data of the servo motor, and constructing a state vector; constructing a reference disturbance observer based on the theoretical parameters, and outputting an observation state, a disturbance value and an observation residual error; a multi-scale time sequence feature tensor is constructed by using the observation residual error and the state vector, and future disturbance is predicted through a CNN-Transform network; carrying out adaptive fusion on the neural network prediction result and the output of the reference observer; performing security constraint on disturbance compensation through a constraint filter and an amplitude limiter; and injecting the constrained compensation signal into a control system, and continuously optimizing the network performance through online incremental learning. According to the method, a traditional observer and a deep learning technology are fused, precise prediction and effective suppression of complex nonlinear disturbance are realized, and the control stability of the servo motor is remarkably improved.

A radio frequency (RF) voltage limiter for a radio frequency identification (RFID) transponder is provided. The RF voltage limiter includes an envelope detector configured to track an envelope of a signal received at the antenna. The envelope detector has an output for providing an envelope signal. A peak detector is included and has an input coupled to the output of the envelope detector. The peak detector includes a current mirror having an input coupled to the output of the envelope detector, and an output configured to provide a control signal. A shunt circuit is coupled to provide an impedance to the antenna in response to the control signal. The impedance decreases with an increasing voltage of the control signal to limit a maximum voltage at the antenna. In another embodiment, a method is provided for limiting a RF voltage at the antenna.

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.

The utility model provides an automatic filling machine which is characterized in that a motion control mechanism at least comprises three groups of linear modules which are perpendicular to one another to form three-dimensional space coordinates, and each linear module comprises a guide rail, a sliding block and a driving element; the filling mechanism is provided with a limiting part and a fixing part, the limiting part limits the filling mechanism to generate shaking displacement except the moving direction of the filling mechanism, and the fixing part limits the displacement in the moving direction of the filling mechanism in the filling process; the posture adjusting mechanisms comprise the first posture adjusting mechanism used for adjusting the angle of the filling mechanism relative to the horizontal plane, and the second posture adjusting mechanism used for adjusting the filling mechanism to rotate along the moving direction axis. According to the utility model, the problems of residue and drip leakage are effectively avoided.

Examples of a load beam are provided. The load beam includes a base portion with an opening at a distal end. The opening is configured to receive a heat assisted magnetic recording (HAMR) head slider extending therethrough. The load beam also includes at least one load beam tab such that the load beam tab is further away from the base portion and a top surface of the HAMR head slider.

The invention discloses an electromechanical electronic speed governor which comprises a rope wheel (3) connected to a support (2) through a main shaft (1) and a control panel (4), an installation frame (8) and a plurality of magnetic blocks (9) are arranged on the other side of the rope wheel (3), and the control panel (4) is installed on the support (2) on the side and provided with a magnetic sensor (10). And the magnetic sensor (10) detects the magnetic field change of the magnetic block (9) on the mounting frame (8) synchronous with the rope wheel (3), transmits sensed data to the control panel (4), and then converts the sensed data into the running speed of the speed limiter. According to the electromechanical electronic speed governor, the control panel is adopted to detect the change of a magnetic field through the magnetic inductor, a sinusoidal waveform is formed, the running speed of the speed governor is calculated through the waveform width, meanwhile, the running direction of the speed governor is detected by arranging the multiple sets of inductors, and therefore the ultra-low speed can be detected.

The invention discloses an intelligent fuse, which comprises a conductor pre-fracture, an explosion device, a cutting device and an amplitude limiter, and is characterized in that the amplitude limiter is connected in series between the explosion device and a conductor at the front end of the conductor pre-fracture and is used for transmitting a generated voltage drop signal to the explosion device when an external circuit is short-circuited; the explosion device comprises two external signal input ports, one external signal input port is connected with the amplitude limiter, and the other external signal input port is connected with the external signal receiver; and the energy generated by the explosion device cuts off the conductor pre-fracture. Based on a transformer-free circuit structure, intelligent control of a circuit trigger signal and an external trigger signal on the fuse is realized, high and low voltage isolation is realized, the current can be automatically cut off at the moment when an external control signal is received or the current exceeds a detection threshold, and finally the purpose of improving the safety of an electrical system is achieved.

The invention discloses a selective action control method, device and system for a blasting type rapid current limiter and a storage medium, and belongs to the technical field of short-circuit current limiting. The method comprises the following steps: acquiring a setting value of the current of the blasting type rapid current limiter; when the current flows through the blasting type quick current limiter, acquiring data of the current flowing through the blasting type quick current limiter, and judging whether the current data is greater than a setting value or not; after it is judged that the blasting type rapid current limiter needs to be prepared for blasting, whether a port of the blasting type rapid current limiter breaks down or not is judged, and a forbidding signal is sent to the adjacent blasting type rapid current limiter when the port breaks down; if the blasting type rapid flow limiter needs to be prepared for blasting and does not receive the forbidding signal, a blasting instruction is output to control the blasting type rapid flow limiter to be blasted. The blasting action selection of the blasting type rapid current limiter is controlled, so that the short-circuit current is limited, and the control accuracy is improved.

A gas distributor for improving ionization efficiency of a radio frequency ion thruster, comprising a gas supply pipeline, a cavity, a flow guide ball, radial rotational flow holes, axial diffusion holes and a flow guide ball limiter, the gas supply pipeline and the cavity are integrally formed, the radial rotational flow holes and the axial diffusion holes are dispersedly arranged in the cavity, the flow guide ball is filled into the cavity through the gas supply pipeline, the flow guide ball limiter is arranged in the cavity to prevent relative movement of the flow guide ball in the cavity, and the gas distributor composed of the gas supply pipeline, the cavity, the flow guide ball, the radial rotational flow holes, the axial diffusion holes and the flow guide ball limiter is arranged at the bottom of a discharge chamber of the thruster.

Capacity-optimized grid-forming is provided. A controller includes a power-synchronization model (PSM). The PSM is configured to receive positive and negative sequence symmetrical components of an output voltage and an output current. The PSM is configured to generate current references including a positive and negative sequence current reference. The PSM is configured to generate an internal voltage phase reference and voltage magnitude reference. The controller includes a capacity constrainer to determine, based on the current references and a capacity limit terms, that a device is capacity constrained. The capacity constrainer is configured to determine optimum complex gains to scale the plurality of current references based on the capacity limit terms. The capacity constrainer is configured to, responsive to the determination of constraint, output scaled current reference to cause a power stage to adjust the output voltage / current, the scaled current reference scaled according to the complex gains.

The invention relates to the field of nuclear fusion devices, and discloses an adjusting device and an assembling method of an annular limiter, the adjusting device comprises a base, a moving part, a limiting part, a second adjusting part and a third adjusting part, the moving part is movably arranged on the base along a first direction; the multiple limiting parts are arranged on the moving part, are arranged at intervals in the first direction and are used for limiting the annular limiter, each limiting part comprises a support and a first adjusting part, and the first adjusting parts are arranged on the supports and can move in the first direction; the second adjusting piece is arranged on the moving piece, the height of the second adjusting piece in the vertical direction is adjustable, the vertical direction is perpendicular to the first direction, and the second adjusting piece is used for supporting the annular limiting stopper; the third adjusting piece is arranged on the base and can drive the moving piece to move in the first direction. According to the invention, accurate position adjustment can be carried out on the annular limiter which has the advantages of large size, heavy weight, multi-direction precision requirement, high installation precision, narrow adjustment space and difficulty in clamping, and the installation reliability of the annular limiter is 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.

The invention relates to the technical field of electric power systems, and discloses a GFL-GFM parallel system fault ride-through control method, system, device and medium, according to the method, under the condition that a GFL-GFM parallel system breaks down, a magnetic flux coupling current limiter is used for achieving fault ride-through, and when the fault of the GFL-GFM parallel system recovers to be normal, fault ride-through is achieved. When the power angle fluctuation of the GFL system and the power angle fluctuation of the GFM system are both larger than a preset power angle fluctuation threshold value, a phase-locked loop parameter of the GFL system and a control parameter of the GFM system are set based on a Sigmoid function until the power angle fluctuation of the GFL system and the power angle fluctuation of the GFM system are both not larger than the preset power angle fluctuation threshold value, the equivalent inertia and damping characteristics of the GFL system and the GFM system are enhanced, and the damping performance of the GFL system and the GFM system is improved. And the whole process of the GFL-GFM parallel system from a fault transient state to fault recovery is controlled, and the robustness of fault ride-through control of the GFL-GFM parallel system is improved.

The invention relates to a fault ride-through method based on hybrid synchronous control voltage / current source mode switching, aiming at fault ride-through (FRT) challenge in a novel power system, and breaking through the limitation of the existing solution from three key dimensions of overcurrent limitation, fault synchronization and reactive power support. On the basis of a hybrid synchronous control strategy, the damping characteristic of the system is remarkably improved, and the synchronous stability of the inverter during the fault period is effectively guaranteed; meanwhile, the intelligent control of smooth mode switching can be completed without complex switching logic or power grid information by utilizing simple detection of a saturation signal of a current limiter and combining with a mixed voltage / current source control architecture. Besides, the method has excellent short-circuit ratio (SCR) adaptive capacity, stable operation can be kept under different power grid strength conditions, and an innovative solution is provided for friendly improvement of new energy grid connection and transient performance optimization of a power system.

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.

The invention discloses a superconductive current limiter simulation modeling method based on PDE and a circuit module, and relates to the working principle and current limiting effect analysis of a resistance type superconductive fault current limiter. The method comprises the following steps: S1, selecting a two-dimensional axial symmetry space dimension, and designing a geometric model according to a solid structure of the pie-shaped superconducting fault current limiter; s2, establishing physical attribute parameters and variables of a plurality of physical fields, and adding materials and physical field boundary conditions; s3, realizing a general form partial differential equation (PDE), solid heat transfer and circuit physical field coupling, and performing mesh generation on the geometric model; s4, setting research steps, and modifying the configuration of the solver until convergence; and S5, post-processing a simulation result, generating one-dimensional diagrams of temperature, current and the like, and drawing data by utilizing Origin. According to the method, the magnetic field and temperature changes of the pie-shaped superconducting fault current limiter under the impact of the instantaneous short-circuit current are analyzed, the current limiting performance of the pie-shaped superconducting fault current limiter is analyzed, the voltage grade and the short-circuit current can be freely set, the operation is simple, and the calculation speed is high.

The invention relates to the technical field of motor excitation control, in particular to an excitation system limiter performance test system and method, and the system comprises a hardware inspection module which carries out the hardware inspection of an excitation system limiter, and obtains a first inspection result which comprises hardware connection information and hardware state information; the parameter setting module is used for performing parameter setting on the excitation system limiter to obtain a first setting result, and the first setting result comprises signal parameter information and load parameter information; the environment simulation module is used for simulating a test environment to obtain a first simulation result, and the first simulation result comprises simulation signal information and simulation load information; the performance testing module is used for testing the performance of the excitation system limiter according to the first checking result and the first setting result to obtain a first testing result; the result adjusting module is used for adjusting the first test result according to the first simulation result to obtain a second test result; and a report generation module.

The invention discloses a short-circuit fault current limiter and a control method thereof. The current limiter comprises a capacitor, two IGBT (Insulated Gate Bipolar Translator) modules and four diode groups, when the line has no short-circuit fault, the two IGBT tubes are controlled to be conducted, and line current flows from the first end of the line to the second end of the line through one IGBT module or flows reversely through the second IGBT module; when a short-circuit fault occurs at the first end of the line, the two IGBTs are controlled to be switched off, the line current flows to the first end of the line from the second end of the line through the first diode group, the capacitor and the fourth diode group, and the capacitor is charged to enable the line to present high impedance so as to restrain the short-circuit current; when a short-circuit fault occurs at the second end of the line, the two IGBTs are controlled to be turned off, the line current flows to the first end of the line from the first end of the line through the third diode group, the capacitor and the second diode group, and the capacitor is charged to enable the line to present high impedance so as to restrain the short-circuit current. The short-circuit fault current limiter is high in response speed and low in equipment cost.

The invention relates to the technical field of YIG magnetic modulation devices, in particular to a low-threshold-power YIG amplitude limiter which comprises a GGG substrate, a YIG film and a grounding metal plate, an excitation strip line set is arranged on the other face of the GGG substrate, and the YIG film and the GGG substrate serve as combined media to form a microstrip line structure; the excitation strip line group comprises a first excitation strip line and a second excitation strip line, the first excitation strip line and the second excitation strip line are arranged in parallel, and the excitation strip line group is etched on the GGG substrate within a certain thickness range, so that the non-uniformity of a radio frequency magnetic field generated by direct contact of the excitation strip line group with the YIG thin film can be reduced, and the uniformity of the YIG thin film is improved. When a non-consistent amplitude limiting effect occurs, high-power energy can be coupled to a half-frequency spin wave for dissipation, and the purpose that the amplitude limiting power threshold value is lower than that of a YIG amplitude limiting structure in which the excitation strip line group is directly manufactured on a YIG thin film is further achieved.

The invention, which belongs to the technical field of the plasma amplitude limiter, discloses a high-power ultra-wideband plasma amplitude limiter comprising an input window, a discharge gap, an output window and an amplitude limiting module. The plasma amplitude limiter is reliable in structure, ultra-wide in band and high in power capacity, is located at the front end of a receiver, and plays a role in protecting high-power microwave attacks. The plasma amplitude limiter disclosed by the invention can bear high-power microwave attack with the highest power magnitude of 10kW in the widest frequency band range of 10GHz, and a receiving access can be quickly switched off within 10ns, so that the aim of protecting the whole communication system is fulfilled; a coaxial ultra-wideband design technology is adopted, a full-hard welding structure is adopted, the structure is stable and reliable, and the frequency band range of the plasma amplitude limiter tube covers L, S, C, X and Ku wave bands; the multi-stage pointed-cone-shaped discharge gaps are adopted, leakage power is reduced stage by stage, and therefore safe work of the amplitude limiting chip is guaranteed, and finally the plasma amplitude limiter with high bearing power and short response time is achieved.

The present disclosure is directed to a rack power distribution unit (RPDU) that automatically and safely switches power to one or more receptacles. The RPDU includes one or more processors utilizing control algorithms that manage bistable relays so that in-rush current is minimized upon manual connection / disconnection of power to a load device. In particular, relay contact status (open / closed) is identified based on changes in RMS or peak voltage influenced by the load impedance. The RPDU is also configured to predict timings for voltage zero-crossing events. In this manner, and based on the determination of relay contact status and voltage zero-crossing prediction, open relay contacts are identified and safely closed at voltage zero-crossing.

The invention relates to a clamping mechanism for rapidly transferring prepreg and a using method of the clamping mechanism. The clamping mechanism comprises a clamping jaw frame, a clamping limiter, a servo motor, a square steel frame, a laser transmitter / receiver, an upper clamping plate, a lower clamping plate, an upper clamping air cylinder and a lower clamping air cylinder, the upper clamping plate and the lower clamping plate are fixed to the clamping jaw frame through the upper clamping air cylinder and the lower clamping air cylinder respectively, and the clamping jaw frame is fixed to the square steel frame through the servo motor. And the clamping limiter and the laser transmitter / receiver are fixed on the square steel frame. The prepreg can be clamped and kept flat by adjusting and controlling the number of the clamping jaws on the left side and the right side of the prepreg and the distance between the clamping jaws, the relative positions of the clamping jaws and the prepreg can be accurately limited through the clamping limiting stoppers, each clamping jaw can be accurately controlled to move independently through the servo motor, and the clamping jaws can be clamped and kept flat. Through the cooperation between the laser transmitter / receiver and the servo motor, the smoothness of the continuous fiber reinforced thermoplastic prepreg in the transfer process can be ensured.

The present invention relates to the technical field of loudspeakers, and in particular to a loudspeaker capable of correcting horizontal deviation of a voice coil, comprising a bracket, a diaphragm, an annular voice coil, a coil, an annular magnet, and a T-shaped yoke; a cylindrical limiter is provided in the middle of the T-shaped yoke; the annular voice coil, the annular magnet, and the cylindrical limiter are arranged concentrically; the cylindrical limiter is provided with a plurality of upper air vents and a plurality of lower air vents; and an air supply mechanism is also provided. The present invention ventilates all the upper air vents and / or lower air vents through the air supply mechanism. Since the plurality of upper air vents are arranged at equal angles and heights around the outer wall of the cylindrical limiter, and the plurality of lower air vents are arranged at equal angles and heights around the outer wall of the cylindrical limiter, the gas ejected from the cylindrical limiter exerts a greater force on the inner wall of the annular voice coil that is closer, and the gas ejected from the cylindrical limiter exerts a smaller force on the inner wall of the annular voice coil that is farther away, thereby correcting the horizontal position deviation of the annular voice coil.