114 results about "Type frequency" patented technology

The invention discloses a low-cost broadband direct synthesis type frequency source, belongs to the technical field of radar communication, and mainly solves the problem that a traditional direct synthesis type frequency source cannot simultaneously realize low phase noise, short frequency hopping time and low cost. The frequency source comprises a harmonic generation circuit, a power division circuit connected with the harmonic generation circuit, a switch matrix connected with the power division circuit, and a frequency mixing synthesis circuit connected with the switch matrix. Wherein the harmonic generation circuit is used for generating a harmonic signal, the power division circuit is used for dividing the harmonic signal into six paths, and the switch matrix is used for outputting two paths of 12-17GHz signals from the power-divided signals. Compared with the traditional direct synthesis type frequency source, the direct synthesis type frequency source disclosed by the invention has the advantages that one harmonic generator and one switch filter group are omitted, so that the direct synthesis type frequency source disclosed by the invention realizes a low-cost broadband direct synthesis type frequency source.

The invention relates to the technical field of frequency converters of power equipment, in particular to a container type frequency converter with internal circulation air cooling, which comprises an outer box body, a closed voltage transformation chamber and a closed frequency conversion chamber are respectively arranged in the outer box body, and a voltage transformation unit and a frequency conversion unit are respectively arranged in the voltage transformation chamber and the frequency conversion chamber. The voltage transformation unit is used for transforming external high-voltage current and then inputting the high-voltage current to the frequency conversion unit, an axial air duct is separated from the bottom of a voltage transformation cavity and the bottom of a frequency conversion cavity through a partition plate, a heat dissipation water tank is arranged in the axial air duct, and a first cooling assembly and a second cooling assembly are arranged in the voltage transformation cavity and the frequency conversion cavity respectively; the heat dissipation water tank is circularly communicated with the first cooling assembly and the second cooling assembly through a first circulating pipeline and a second circulating pipeline respectively; an axial heat dissipation fan is further arranged at an opening in one end of the axial air duct; the heat dissipation of the variable frequency chamber and the variable pressure chamber is promoted, and the better use effect is ensured.

The invention discloses a flexible direct current system consistency cooperative frequency supporting method and device based on a state factor, and relates to the technical field of flexible direct current system cooperative frequency supporting, and the method comprises the steps: obtaining related data of a plurality of types of frequency modulation sources, carrying out the calculation of the state factor based on the related data of the plurality of types of frequency modulation sources, and obtaining the state factor of the plurality of types of frequency modulation sources, the related data of the multiple types of frequency modulation sources comprises parameter data of the multiple types of frequency modulation sources, safety upper and lower limit data of the multiple types of frequency modulation sources and parameter data of the multiple types of frequency modulation sources when a frequency event occurs; based on the state factors of multiple types of frequency modulation sources, consistency control is carried out, through consensus protocol regulation and control, each frequency modulation source controls the corresponding state factor to be consistent with the disturbed power grid, so that mutual binding is realized, and frequency support is provided for the disturbed power grid according to the frequency modulation capability of the frequency modulation source, the multi-class frequency modulation source comprises an offshore wind turbine generator, a flexible direct current system, a non-synchronous alternating current power grid and an energy storage system, frequency modulation energy of the whole system is reasonably called to participate in disturbed power grid frequency support, and safety and stability of the frequency modulation source are guaranteed.

The invention relates to the technical field of power electronics, and discloses a fusion type frequency division converter which comprises a main power conversion unit based on an IGCT tube, an active power filtering unit based on an IGBT tube and an output unit, the first end of the main power conversion unit is connected with direct current, and the second end of the main power conversion unit is connected with the first end of the output unit; the first end of the active power filtering unit is connected with the second end of the output unit, and the second end of the active power filtering unit is grounded; the third end of the output unit is connected with the to-be-powered device. The application range of the IGCT is widened to the fields of new energy power generation, energy storage and the like, and the advantages of the IGCT are fully played by reducing the switching frequency, so that the current situation that new energy power generation and energy storage are exclusively occupied by an IGBT is broken through.

The utility model discloses a kind of internal electronic device partition installation type frequency converters, its shell is separated into left side chamber, middle air duct and right side chamber by left, right partition, left side chamber sets up rectifier module group and direct current contactor, right side chamber sets up drive board and IGBT module group, air duct installs radiator, capacitor group transversely penetrates air duct and is fixed between left, right side partition, realize that rectifier module group and IGBT module group share radiator;Shell top is equipped with protective piece and receives control panel, inlet group external fan group brings in airflow and carries away heat.The utility model concentrates high heating element in air duct both sides by partition installation, utilizes shared radiator and fan group to realize high-efficiency heat dissipation, avoid heat interference;Control panel is independently laid in top protective piece, and optimization space utilization rate;The utility model is in guaranteeing heat dissipation performance, through structure optimization makes overall layout compact, reduce the volume of frequency converter, it is favorable to reduce cost.

The utility model discloses a modularized dislocation type frequency conversion cabinet, the back side of a cabinet body is provided with a back plate which can fully seal an opening at the back side of the cabinet body, the cabinet body is internally provided with a vertical partition plate which divides the cabinet body into a front cavity and a rear cavity, and the vertical partition plate and the cabinet body are integrally formed. The cavity close to one side of the cabinet door is a switch cavity, and the cavity close to one side of the back plate is a staggered mounting cavity; the staggered quick-release assembly is detachably arranged in the staggered mounting cavity, the quick-release assembly comprises staggered transverse partition plates and staggered longitudinal partition plates, the staggered transverse partition plates are detachably connected with the cabinet body, and the staggered longitudinal partition plates are detachably arranged between the two staggered transverse partition plates; the corresponding frequency converters can be arranged on different mounting plates through the detachable staggered transverse partition plates and the staggered longitudinal partition plates, and when the frequency converters are used for the second time, the corresponding connecting lines of the frequency converters can be directly disassembled, and then the staggered longitudinal partition plates can be directly disassembled, so that complete disassembly can be realized; and the traditional method that the fixing bolts can be taken out after being completely detached is avoided.

This high-frequency signal generation device is provided with: (A) a clock signal generation unit that generates a clock signal using a harmonic component generated by an amplifier having nonlinearity; (B) a direct digital synthesizer (DDS) that generates a frequency signal having a frequency set by the frequency setting data, using the clock signal as a system clock for operating the internal processing; and (C) a frequency-increasing unit that is configured from a non-active frequency multiplier that does not use an active element, and that increases the frequency of the frequency signal generated by the DDS. A clock signal is generated using a harmonic component generated by an amplifier having nonlinearity, and in a frequency variable function, a delay time is shortened to cope with a high speed, and spurious and phase noise are suppressed to cope with a high C / N ratio.

The utility model discloses a backpack type frequency converter, the structure of which comprises a control box, an adapter plate and a motor, the adapter plate is used for fixedly connecting the control box to the motor, the control box further comprises a main shell and a surface shell, the main shell is further provided with a preformed groove, the preformed groove is matched with a mounting piece on one side of the motor, and the mounting piece is arranged on the surface shell. The face, opposite to the motor, of the main shell is a concave face, the angle of the concave face is matched with the outer arc of the motor, the concave face, opposite to the motor, of the main shell is further provided with cooling fins, the cooling fins are arranged right opposite to an air hole in the tail of the motor, and cooling is conducted based on the motor. According to the backpack type intelligent frequency converter, the frequency converter is combined with the structure improvement of the outer contour of the motor, the main shell which is integrally cast iron and is provided with the radiating fin structure is adopted, and the frequency converter is simultaneously radiated based on the radiating fan blades of the motor, so that the space occupation, the material consumption and the power consumption of an independent radiating assembly of the frequency converter are reduced; the structure also enables the frequency converter and the motor not to be easy to loosen and fall off during installation.

The invention belongs to the technical field of power system control, and the method comprises the following steps: improving a manual failure area unit of primary frequency modulation, when a frequency deviation delta F'exceeds a frequency dead zone Ef, increasing a superposition amount for the calculated frequency deviation delta F, and when primary frequency modulation action is carried out, adding a delay filtering link; optimization is carried out on the superposition amount and the delay link for adaptive adjustment, and prediction and multi-stage frequency modulation are carried out during a primary frequency modulation action; and when the primary frequency is reset, a return difference link is added. According to the method, the algorithm of the manual failure area is improved, a step-type frequency superposition amount is added to the calculated frequency difference, and the adjustment amount of frequency modulation is increased, so that the problem of insufficient integration of frequency modulation is overcome; when the frequency deviation is weak, a step type is added to form a larger output signal, the signal output form is a sudden change form, and the dead zone of each link is overcome; time delay and return difference are increased, and frequent jitter which is useless for primary frequency modulation and is caused by frequency crossing of a frequency dead zone edge of a power grid system is prevented.

The utility model relates to the technical field of electric power control equipment, and discloses a novel fast plug type frequency converter, which comprises a frequency conversion speed regulator, a rectangular box and two supports, one side of the frequency conversion speed regulator is welded with the rectangular box, the inside of the rectangular box is rotatably connected with a double-thread screw rod, the top end of the double-thread screw rod is fixedly connected with a knob through a rotating shaft, and the knob is fixedly connected with the rectangular box. The bottom and the top of the double-thread screw are both in threaded connection with sliding tables, clamping grooves are formed in the middles of one sides of the two sliding tables, and the two clamping grooves are both connected with clamping blocks in a clamped mode. The rotary shaft is rotated through the rotary knob to drive the double-thread screw to rotate, the double-thread screw can drive the two sliding tables to move oppositely, the distance between the two baffles can be shortened, the two insertion blocks can be inserted into the insertion grooves of the two supports correspondingly, the two insertion blocks are clamped through insertion, and rapid installation is convenient. The height of the sliding table can be kept through friction force between the double-thread screw and the threaded cylinder.

The present invention relates to the technology of motor variable-frequency drive, and particularly relates to a three-phase bridge series-type variable-frequency drive system and a layout method. The system includes a rectifier, m three-phase units, and an AC motor; each three-phase unit includes a three-phase bridge inverter, a capacitor connected in parallel on the DC side, and a DC bypass switch; the positive and negative DC input terminals of the m three-phase units are connected in series in sequence and connected to the DC output terminal of the rectifier; the stator winding of the AC motor includes m mutually isolated sub-windings; the AC output terminals of the m three-phase units are respectively connected to the three-phase terminals of the m sub-windings of the AC motor; m is a positive integer. This system independently supplies power to each sub-winding of the motor stator with each three-phase unit, and by using the isolation between the sub-windings of the motor stator, the phase-shifting transformer installed to achieve input-side power isolation for each unit and the three-phase uncontrolled rectifier circuit of each unit in a conventional cascaded inverter are omitted, improving the power density of the variable-frequency drive system.

The invention discloses a cascade frequency selective surface with a steep transition band and a wide passband. The cascade frequency selective surface sequentially comprises a frequency selective surface with a steep sideband, a honeycomb core layer and a frequency selective surface with a wide passband from top to bottom along a Z-axis direction, the frequency selective surface with the steep sideband is used for providing a frequency response characteristic of rapid roll-off at the edge of a passband to form a steep transition band; the frequency selective surface with the wide passband is used for providing a broadband wave-transparent characteristic and a broadband stop-band suppression characteristic; the honeycomb core layer is used for cascading a frequency selective surface with a steep sideband and a frequency selective surface with a wide passband; and electromagnetic coupling between the upper and lower layers of frequency selection surfaces is reduced, so that the frequency selection surface with a steep sideband and the frequency selection surface with a wide passband maintain relatively independent resonance characteristics. According to the invention, the square annular patch with central symmetry is used, and the four branches are added, so that the symmetry enables the angle to be stable, and the processing complexity is simplified.

The invention discloses an angle-adjustable frequency stabilization device for a laser gyroscope, and belongs to the field of laser gyroscopes. The device comprises a frequency stabilization spherical mirror and an annular thin rib structure formed by processing a glass material, coaxial columnar protrusions are arranged at the two ends of the center of the frequency stabilization spherical mirror, the end of the columnar protrusion at one end is a concave spherical surface, and the columnar protrusion at the other end is a jackscrew contact surface; the clamping mechanism is used for installing the frequency stabilization spherical mirror; the 3-4 jackscrews are connected with the grabbing and clamping mechanism through threads, and the end surfaces of the jackscrews are in tight contact with the jackscrew contact surfaces on the columnar bulges of the frequency stabilization spherical mirror; the two piezoelectric ceramic pieces are arranged on the upper surface and the lower surface of the card grabbing mechanism respectively and used for achieving frequency stabilization through voltage control. According to the invention, through different screw-in amounts of 3-4 jackscrews, the reflection angle of the frequency stabilization spherical mirror can be accurately adjusted, the angle processing error of a laser gyroscope cavity is made up, and the problem that a new angle error may be introduced due to the fact that the angle of an existing clamping type frequency stabilization control mirror cannot be adjusted is solved.

The invention discloses a V-type frequency modulation signal generation method and system, and the method comprises the steps: obtaining a discrete model of a V-type frequency modulation signal, and obtaining a frequency increment and a frequency initial parameter through the first-order difference relation between the frequency and the phase of the discrete signal; taking the frequency increment, the frequency initial parameter and the constant term as positive frequency modulation digital control parameters, constructing a linear increasing sequence based on the frequency increment, obtaining instantaneous frequency values at different moments by sequentially superposing the frequency initial parameter, and superposing the constant term on the instantaneous frequency values at different moments to obtain a phase sequence of the positive frequency modulation slope; negation processing is carried out on the positive frequency modulation digital control parameters, and a phase sequence of a negative frequency modulation slope is obtained through calculation; and according to the sinusoidal waveform, converting the phase sequence into amplitude data, and generating a V-shaped frequency modulation signal. By optimizing parameter configuration logic and simplifying operation, the operation amount of control parameters and the data transmission amount in the signal generation process can be greatly reduced, the calculation efficiency is remarkably improved, and the consumption of calculation resources is reduced.

The utility model relates to the technical field of frequency converter dust prevention, in particular to a dustproof heat dissipation type frequency converter, which comprises a frequency converter body, and a shell of the frequency converter body is provided with a scavenging port; the X first barrier strips are uniformly arranged at the scavenging port, and each first barrier strip extends in the first direction; the Y second barrier strips are uniformly arranged at the ventilation port, each second barrier strip extends in the second direction, each first barrier strip is provided with Y guide holes, and each second barrier strip is slidably arranged at each guide hole of each first barrier strip; the first driving mechanism is connected with the second barrier strips and used for driving the second barrier strips to slide in the second direction; the scraping mechanism is connected with the first barrier strip and is used for scraping dust adsorbed on the first barrier strip; and the fan is arranged in the shell of the frequency converter body and is arranged corresponding to the scavenging port. The utility model relates to a dustproof heat dissipation type frequency converter, and aims to solve the problem that heat dissipation is affected due to blockage of a dustproof net in the rightward technology.

The invention discloses a low-profile band-pass frequency selective wave-absorbing surface with broadband wave absorption. The low-profile band-pass frequency selective wave-absorbing surface comprises a resistance loss layer, an air layer and a band-pass FSS transmission layer in sequence from top to bottom, the resistance loss layer comprises a first dielectric substrate, a central metal sheet is printed at the center of the upper surface of the first dielectric substrate, an etching groove is etched in the central metal sheet, a parallel LC resonance circuit is formed through the etching groove, the periphery of the central metal sheet is connected with metal bridge arms which are symmetrically distributed in a central rotation mode and extend outwards, and the metal bridge arms are connected with the first dielectric substrate. The tail end of each metal bridge arm is connected with a circular metal sheet which takes the midpoint of the tail end of the metal bridge arm as a circle center, and lumped resistors are loaded on the metal bridge arms; through the single resistance loss layer, loading of the lumped resistor and special slotting of the resistance loss layer, broadband wave absorption with a band-pass window can be realized by using a two-dimensional structure, and the broadband wave absorption device has the characteristics of low profile, easy processing, flexible regulation and control and the like.

The utility model discloses a three-axis drive frequency converter, an air conditioner electric control box and air conditioning equipment, relates to the technical field of power electronics, is used for providing a frequency conversion control function, and provides the three-axis drive frequency converter aiming at the problems caused by the scheme that three split-type frequency converters are adopted for a compressor, a fan and a water pump at present. Three original split-type frequency converters corresponding to a compressor, a fan and a water pump in the air conditioning equipment are achieved through a one-to-one single-shaft frequency conversion module and a one-to-two double-shaft frequency conversion module, and the single-shaft frequency conversion module and the double-shaft frequency conversion module are integrated on the same mainboard. Three motor devices can be simultaneously controlled to operate through one circuit board. According to the scheme, the problem that the overall size is increased due to a split-type frequency converter is solved, connecting wire harnesses between the frequency converters are reduced, the material cost of air conditioning equipment can be controlled, and the overall production efficiency can be improved.

The utility model relates to the technical field of variable-frequency doors, in particular to a novel variable-frequency door lifting inching control and empty and heavy box recognition device which comprises a lifting inching control structure, an empty and heavy box recognition device body and an external connecting wire, the lifting inching control structure is electrically connected with the external connecting wire, and the external connecting wire is electrically connected with a retracting and releasing assembly. The collecting and releasing assembly is rotationally connected to the inner side of the empty and heavy box recognition device body, an electric connection plate assembly is fixedly connected to the inner side of the empty and heavy box recognition device body, and a limiting assembly is fixedly connected to the inner side, close to the upper end of the collecting and releasing assembly, of the empty and heavy box recognition device body. According to the device, the situation that abrasion is increased due to the fact that a circuit is too long and is wound is avoided, potential safety hazards are reduced, meanwhile, adjustment of the circuit in the later maintenance process cannot be affected due to the fact that the length of the circuit is right, and the maintenance convenience of the device is improved.

The present disclosure provides a determination method, an apparatus, a device, and a storage medium. The method comprises: if the sum of the transmit powers corresponding to all first channels on a first transmission occasion for sending at least one first channel is greater than the maximum transmit power corresponding to the first transmission occasion, determining a first transmit power and a second transmit power which correspond to each first channel, wherein the first transmission occasion comprises a first-type frequency domain resource and a second-type frequency domain resource, the first-type frequency domain resource is a common frequency domain resource, the second-type frequency domain resource is a dedicated frequency domain resource, and the first transmit power and the second transmit power cause the sum of the transmit powers corresponding to all first channels on the first transmission occasion not to be greater than the maximum transmit power. The determination method provided by the present disclosure can be used to control the power of the first channels, can enhance the transmit powers of signals on the first channels, improves the capacity of the first channels, and ensures the communication stability.

The application discloses a kind of wide band low insertion loss high selectivity frequency selective surface and application.It includes several unit structures, unit structure includes main structure and longitudinal structure, main structure includes two layers of rotation symmetry, aperture type frequency selective surface screen interval parallel arrangement of the dielectric layer and metal layer, longitudinal structure includes vertical and auxiliary metal strip, vertical metal strip upper end penetrates the through groove of upper aperture type frequency selective surface screen and does not contact electrically connected;Vertical metal strip bottom is equipped with auxiliary metal strip, auxiliary metal strip is pasted on the upper surface of lower aperture type frequency selective surface screen dielectric layer.The application inserts transmission zero between stop band and passband by longitudinal structure, realizes the low loss and high selectivity of passband transmission response under dual polarization, effectively improves the isolation of multi-frequency antenna array, improves the antenna pattern deterioration problem caused by co-aperture antenna coupling, with the characteristics of wide band, high selectivity, low loss, low profile, simple structure.

The utility model discloses a cabinet type frequency converter replacement tool, which relates to the technical field of tools, and comprises a plane steel plate, one side of the plane steel plate is provided with an inclined plane steel plate, four corners of the bottom of the plane steel plate are provided with mounting cylinders, the inner parts of the mounting cylinders are provided with adjusting seats in an inserting manner, the inner walls of the mounting cylinders are provided with internal threads, and the adjusting seats are provided with external threads. And external threads are arranged on the outer walls of the adjusting seats. The beneficial effects are that the plane steel plate and the inclined surface steel plate form a complete slideway steel plate, and the surfaces of the plane steel plate and the inclined surface steel plate are not provided with any groove, so that the frequency converter can smoothly move to the plane steel plate from the cabinet body, then move to the inclined surface steel plate from the plane steel plate, and finally move to the ground from the inclined surface steel plate; according to the utility model, the whole process is free from jamming, the time for replacing the frequency converter is shortened, the working efficiency is improved, the time-saving and labor-saving effects are realized, and the practical applicability is better.

This invention discloses a distributed control-based network-type energy storage frequency regulation control system, comprising: a data acquisition module for acquiring operating data from each network-type energy storage unit and generating network-type energy storage operating data; a frequency regulation demand identification module for extracting frequency deviation and frequency change rate to generate local frequency regulation demand; a neighborhood information interaction module for interacting with operating status and frequency regulation demand to generate neighborhood interaction status; a distributed weight calculation module for generating distributed frequency regulation allocation weights; a frequency regulation power sharing module for generating energy storage frequency regulation power sharing; a state of charge coordination module for generating coordinated energy storage frequency regulation power sharing; a network-type frequency support module for generating network-type frequency support control quantities; and a safety constraint correction module for generating energy storage frequency regulation control results. This invention has the advantages of balanced frequency regulation allocation, stable frequency support, and high operational safety.

The application provides a driving fault feedback method and a feedback system. The method first determines frequency segments corresponding to different fault types; then feedbacks a detected fault level signal for logical processing; evaluates fault priority, changes the fault level signal to a low level according to the priority, changes the low level to a high level after a plurality of counting points, takes the high level as an initial value, and continuously outputs frequency signals corresponding to different fault types; finally collects the frequency signals, counts values between two rising edges, and determines a fault type according to the obtained counting values and the fault type frequency segments. The method uses a single channel to feedback fault information, transfers fault information according to feedback pulse frequency, and different frequency bands represent different faults, so that different fault types can be distinguished. By setting a wide fault frequency band and a frequency interval zone, the influence of interference can be greatly reduced.

The invention discloses a frequency mixing regulation and control method and device based on a four-bridge-arm type frequency mixing solid-state transformer. The method comprises the following steps: respectively calculating modulation signals of four sub-bridge arms in the solid-state transformer; performing quantization processing on the modulation signals of the four sub-bridge arms by using nearest level approximation modulation to generate step waves, and determining the number of basic sub-modules put into use in each sub-bridge arm according to the voltage amplitude of the step waves; in the control period, if the step waves change, the corresponding sub-bridge arms are controlled; in the control period, if the voltage imbalance value is larger than the corresponding threshold value, the N sub-modules in the sub-bridge arm are put into use, and N is the number of the basic sub-modules. According to the technical scheme, control is performed only when step waves change, so that the switching action times of the sub-modules are remarkably reduced, and the switching frequency is reduced; only when the voltage imbalance value is too high, forced sequencing control is carried out on sub-module switches in the sub-bridge arms, the switching frequency is reduced, and the switching loss is reduced.

A communication method comprises: determining, by a first communication device, whether to transmit a first measurement report based on a first condition in response to a first-type frequency point meeting a first reporting condition.

The invention discloses an automatic repair type frequency source and an implementation method thereof, and belongs to the technical field of radar communication and frequency synthesis. In order to solve the problems that after a traditional frequency source breaks down, the maintenance efficiency is low, and the shutdown loss of a system is large, a double-backup hardware architecture of two sets of phase-locked loops and two sets of radio frequency signal conditioning circuits is adopted, intelligent management of power supply and signal paths is achieved through a radio frequency switch network, and the working state of each assembly is collected in real time through a monitoring module; and the FPGA control unit executes an automatic repair action based on a locking detection signal and a level signal fed back by the monitoring module, so as to realize instant diagnosis and seamless switching of a fault. According to the invention, the fault repair time is shortened from several days in the prior art to milliseconds, the zero-shutdown operation of the system is realized, the economic loss of hundreds of thousands of yuan is effectively avoided by increasing the hardware cost of thousands of yuan, and the usability and maintainability of the high-reliability electronic system are remarkably improved.

In a signal sending method, a first communication device generates and sends a first signal. The first signal is mapped to respective frequency domain subbands of N time units, and a frequency domain subband of each time unit includes a first-type frequency domain area and at least one second-type frequency domain area. A second-type frequency domain area in a frequency domain subband of an ith time unit overlaps a second-type frequency domain area in a frequency domain subband of an (i+1)th time unit. The first signal is mapped to the first-type frequency domain area by using a first comb, and mapped to the second-type frequency domain area by using a second comb, and the second comb is less than the first comb.

The invention discloses a multi-scene power system frequency safety index self-adaptive partition reconstruction method, which comprises the following steps: acquiring multi-type frequency modulation resource parameters of a system, and establishing an analytical expression of nonlinear frequency safety index constraints based on a system multi-machine frequency response dynamic model considering multi-type frequency modulation resources; acquiring an original feasible range of system frequency modulation parameters, and sampling to generate an original frequency modulation parameter region and a frequency safety index sample curved surface set in the feasible range of the system frequency modulation parameters; acquiring all sample point subsets on an inertia boundary in the frequency modulation parameter area by traversing sample points meeting a specific equivalent inertia value of the system, acquiring intersection points of frequency safety indexes corresponding to the sample points and constraint limit values of the sample points on an original frequency modulation parameter area boundary, and re-partitioning the original frequency modulation parameter area into a plurality of subareas; and linearizing the linear sub-region which needs to be linearized, outputting a linearization parameter which meets a linear error threshold value requirement, and reconstructing a frequency safety index constraint after partition linearization.

The utility model relates to the field of frequency converters, in particular to a high-sealing vector type frequency converter. The frequency converter comprises: a housing; the positive pressure ventilation structure comprises an air supply structure mounted at the bottom of the shell and heat dissipation holes formed in the top of the shell; the air supply structure comprises an air pipe joint mounted at the bottom of the shell, an external air source communicated with the air pipe joint, and filter cotton mounted at the end part of the air pipe joint; blocking pieces capable of being turned over upwards are arranged at the heat dissipation holes, and the blocking pieces are configured to be turned over when air flow penetrates through the heat dissipation holes to flow upwards and seal the heat dissipation holes when the air flow stops flowing upwards. The high-sealing vector-type frequency converter has two effects of heat dissipation and dust prevention, external dust can be prevented from entering the frequency converter along with airflow, the heat dissipation effect of the frequency converter is ensured, and the service life of the frequency converter is prolonged.

The utility model relates to the technical field of finished paper length control of a rewinding machine, in particular to a control structure for controlling the length of finished paper based on the rewinding machine, which comprises a large plate, a mounting seat is fixedly connected to the side wall of one side of the large plate, and a first rotating shaft and a second rotating shaft are rotatably connected to the side wall of one side, far away from the large plate, of the mounting seat; the first rotating shaft and the second rotating shaft are located at the same height and are symmetrically distributed about the central axis of the mounting base, and first gears are fixedly connected to the outer wall of the first rotating shaft and the outer wall of the second rotating shaft. According to the utility model, a mathematical model formula is improved, the length of the roll paper is calculated by utilizing the mathematical model formula L = V * T (L is the length of the finished paper roll, V is the running speed of the bottom roller, and T is the running time of the bottom roller), and the 32-bit vector type frequency converter is matched with the programmable controller, so that more complicated control algorithms and more accurate control can be processed; the length of the roll paper can be more accurate, the utilization rate of the roll paper is greatly increased, and the production yield is increased.