86 results about "Compensation principle" patented technology

The invention relates to a cement decomposing furnace temperature control method based on constraint smith GPC, which includes variable selection, model recognition, optimizing computation, constraint processing and feedforward compensation; the variable selection includes that: coal powder flow is selected as a control variable, raw flow is selected as the feedforward variable and the decomposing furnace temperature is selected as the controlled variable; the model recognition includes that: the model recognizer based on least square method and retardation time estimation time is adopted to obtain a pulse transfer function model; the optimizing computation includes that: the future output state is predicated and the reference track w of the output value is also set; a secondary performance index controller is adopted for the rolling optimization, the control increment Delta u of the current time is computed to obtain control action value u through addition; the constraint processing includes that: the control variable and controlled variable are respectively performed with constraint amplitude limiting processing; the feedforward compensation includes that: the dynamic compensation principle is utilized to compute the current time t added to the feedforward control action value ud. The invention has simple recognition process, less adjustable parameters, good tracking performance, strong robustness, effectively refrains the disturbance influence caused by raw material flow and prevents saltus step of the system variable.

The invention provides a temperature self-compensation fiber grating displacement sensor which has a structure that two bare fiber gratings which are encapsulated by capillary metal tubes are connected with a probe through a metal connecting block, a spring and a centre rod to form a main body of the temperature self-compensation fiber grating displacement sensor to execute functions; then the main body is arranged in a metal box; finally, the end parts of the capillary metal tubes are fixed with the metal box through the metal connecting block, fibers penetrate out from small holes positioned on the metal connecting block and the lateral wall of the metal box, and the probe can freely stretch through a guide rod hole of the metal box. When a displacement sensor is arranged on the structure, the probe and the metal box relatively move to enable the bare fiber gratings to extend or shorten so as to generate the drift of the operating wavelength of the bare fiber gratings when the structure generates displacement, and the displacement and the temperature of the structure can be tested by utilizing a temperature compensation principle and a displacement computing formula of the displacement sensor.

An embodiment of the invention is a time-delay invariant predistortion approach to linearize power amplifiers in wireless RF transmitters. The predistortion architecture is based on the stored-compensation or memory-compensation principle by using a combined time-delay addressing method, and therefore, the architecture has an intrinsic, self-calibrating time-delay compensation function. The predistortion architecture only uses a lookup table to conduct both the correction of non-linear responses of a power amplifier and the compensation of any time-delay effects presented in the same system. Due to the time-delay invariant characteristic, the predistortion design has a wider dynamic range processing advantage for wireless RF signals, and therefore can be implemented in multi-carrier and multi-channel wireless systems.

The invention relates to a device for detecting methane or carbon dioxide through optical interference, which comprises an optical path system using the same optical source to generate two groups of optical interference stripes, an image sensor converting the physical position information of the two groups of stripes into electric signals, and an electric signal collecting and processing part used for identifying the physical positions of the two groups of stripes and finally determining the methane content in the air. The invention also comprises a method for detecting the concentration of methane and carbon dioxide with the advantage of automatic zero tracking and precision automatic compensation capacity. The device and the method have the characteristic of adopting two groups of stripes in the same optical path to realize the differencing of the optical images; then the whole system processes data in a differencing mode, which greatly improves the anti-interference capacity of equipments. The device and the method are based on the automatic compensation principle of instrument precision, solve the difficulties of severe precision unbalancing and severe zero point excursion of the traditional optical interference methane detecting instrument caused by the aberration of the optical system, can intelligently identify when the precision of the instrument is severely unbalanced, and can effectively calibrate.

The invention discloses a control method of a wide frequency range multi-type harmonic comprehensive governance system. The control method of the wide frequency range multi-type harmonic comprehensive governance system comprises the wide frequency range multi-type harmonic comprehensive governance system. The wide frequency range multi-type harmonic comprehensive governance system comprises a series active power filter and a parallel passive power filter. The series active power filter comprises an inverter, a filter circuit, and a series transformer. The inverter is connected with a secondary side of the series transformer through the filter circuit. A primary side of the transformer is in series connection with grid lines. The parallel passive power filter is in parallel connection with a load side of the series active power filter. The control method of the wide frequency range multi-type harmonic comprehensive governance system is based on a control method of a fundamental wave magnetic flux compensation principle of the transformer. A fundamental wave compensating current is injected at the secondary side of the transformer. The size of the fundamental wave compensating current is k times larger or smaller than a power system current, and the direction of the fundamental wave compensating current is opposite to that of the power system current. Impedance of the series transformer to a fundamental wave is zero. Normal operation of the power system cannot be influenced. High impedance to the harmonic wave is presented. Filtering effect of a passive power filter can be improved. A harmonic voltage is compensated. Simultaneously, resonance of power harmonic in series or parallel connection can be well restrained.

The invention discloses an asymmetric prediction error histogram modification-based reversible information hiding method. The method comprises the following steps of performing overflow preprocessing;calculating a peak point and a zero point; embedding secret information; extracting the secret information; and performing overflow recovery processing. A compensation principle can be well utilizedno matter whether an embedded information quantity is maximal or minimal; when the embedded information quantity is relatively small, fewer pixel points can be modified, so that the quality of a secret-carrying image is improved; and meanwhile, by utilizing secondary embedding, the image quality is improved while the embedding capacity is expanded.

The invention discloses a titanium alloy welded case installation edge pre-deformation welding and micro forming method. The method comprises the following steps of: designing and making an installation edge with process allowance according to the welding deformation tendency and the deformation; making a thin-wall main body matched with the installation edge with process allowance; combining and welding the installation edge and the thin-wall main body together by using a combining and welding clamp; and performing micro formation and eliminating welding stress by using a heat setting tool and vacuum heating equipment, and thus obtaining a welded case shell blank. According to the method, the technical problems of welding deformation of the installation edge and poor coaxiality after the front and rear installation edges are welded are effectively solved by using the deformation compensation principle and adopting the pre-deformation welding and micro forming process, and the technical requirement for the blank before welded case machining is met.

The invention discloses an image verification code generation method utilizing a human eye vision compensation principle. The image verification code generation method comprises the following steps: 1, generating a random character string with a random length, wherein the length of the random character string is controlled in a certain set range; 2, selecting an unequal-width typeface and writing the random character string into image canvas with a non background color; 3, rewriting the random character string into the image canvas with a background color and moving the position in the image canvas towards the top left corner by one pixel, wherein a typeface form of each character is totally the same with that of each character in the step 2; 4, carrying out stroke random erasing processing on a verification code image generated in the step 3, wherein an erasing ratio is a set value. People can reduce the image verification code generated by the image verification code generation method into stereoscopic words by utilizing the human eye vision compensation principle, so that identification is easily carried out; strokes of verification code words or characters are very slim, discontinuous and incomplete so as to cause difficulty of a machine in identification.

The invention relates to a method for measuring a grounded resistance of a grounded screen by a short range measuring method, which comprises the following steps: selecting the position of an current electrode; carrying out simulation calculation on the ground potential distribution of an earth screen without the current electrode and an earth screen with the current electrode according to the true form of the grounded screen to be measured by a numerical computing method so as to determine the position of a compensation point, i.e. the measuring position of a voltage electrode; and finally carrying out measurement to obtain the value of the ground resistance. The method for measuring the grounded resistance of a transformer substation by the short range measuring method provided by the invention adopts a shorter current electrode and a voltage electrode lead to realize measuring the grounded resistance by the short range measuring method according to the potential compensation principle, saves manpower and material resources, and has important project practical value.

The invention provides a two-valued method for license plate based on compensation principle and center region scanning. Firstly, the license plate region is converted through grey level stretching to realize reinforcement of the character region on the license plate; second the grey levels of the character pixel element and the background pixel element g1 and g2 of the reinforced license plate are figured out through a histogram method; thirdly the mean and the standard deviation of the reinforced license plate image is calculated and an illumination compensation factor is also obtained according to the mean and the standard deviation; fourthly an illumination penalty function is accordingly calculated based on the illumination compensation factor; fifthly a two-valued threshold value is consequently obtained according to the illumination penalty function, the standard deviation and the mean; and finally the type of the license plate can be judged through a center region scanning method with normalization treatment. Compared with the prior global dynamic thresholding method, the method of the invention has the advantages of not only quick two-valued process, but also high robustness and realization of complete separate between background and characters.

The invention discloses a control method of a railway power regulator based on a half-bridge structure. The railway power regulator based on the half-bridge structure is composed of two half-bridge arms, and the two half-bridge arms are connected with each other by two capacitors. Since the voltage at the DC side is powered by two series capacitors, the problem of voltage sharing exists. In orderto realize voltage sharing at the DC side, a voltage sharing PI regulator is used for controlling the deviation of the two capacitor voltages, and the offset output by the voltage sharing regulator directly influences the charging and discharging current of the two capacitors, thereby reducing the deviation to 0. In order to keep the voltage at the DC side stable, the voltage external ring at theDC side uses a PI controller to regulate the output value, and the output value is respectively multiplied by the synchronizing signals of the two power supply arms, and superposed by the harmonic and negative sequence compensating current reference signal obtained by computation according to the VV traction system negative sequence and the harmonic compensation principle, thereby obtaining the current reference signal of the two half-bridge converters. In order to realize quick tracking of internal ring current, a hysteresis control method is used for the output currents of the two converters, so that the currents from the output ends of the two converters track the reference compensating signal, thereby realizing negative sequence and harmonic compensation.

The invention discloses a cable and overhead line mixed line double-end traveling wave fault location algorithm based on the piecewise compensation principle. According to the cable and overhead line mixed line double-end traveling wave fault location algorithm, the difference between the time when a fault initial traveling wave surge reaches a measuring point on one side of a line and the time when the fault initial traveling wave surge reaches a measuring point on the other side of the line is compared with the difference between the time when traveling wave propagation at each connecting point of the mixed line reaches the measuring point on one side of the line and the time when the traveling wave propagation at each connecting point of the mixed line reaches the measuring point on the other side of the line to determine a fault section, and then time and distance compensation is conducted to express the fault distance as the sum of the distance from the endpoint of the fault section to the measuring point and the vector distance from the fault point to the endpoint. Compared with an existing mixed line traveling wave fault location method, the cable and overhead line mixed line double-end traveling wave fault location algorithm is higher in adaptability, clearer in concept, easier to implement, and unified with a traditional uniform transmission line two-end fault location algorithm in form and physical meaning.

The invention discloses a method for detecting the peripheral defect of a hollow cylinder by an ultrasonic frequency dispersion compensation principle. The method comprises the following steps of (1) stimulating out ultrasonic guide waves in the hollow cylinder, and using a guide wave receiver for respectively obtaining a reference signal s<ref>(theta,t) and a peripheral defect echo signal s<obj>(theta,t); (2) calculating the peripheral defect position according to the time differences and the sound speed of the two signals; (3) performing two-dimensional Fourier transform on the s<ref>(theta,t) and the s<obj>(theta,t), exerting the phase shifting, and performing the one-dimension Fourier conversion relevant to the (n-theta) transform pair to obtain the distributions shown as the accompanying drawing on a (theta, omega) domain; (4) using the first distribution shown as the accompanying drawing as the reference for performing Wiener filtering on the second distribution shown as the accompanying drawing; (5) calculating the distribution A(theta) of the amplitude value s<dec> (theta,t) along the hollow cylinder peripheral rotating angle theta and the half height width of the distribution A(theta), i.e., the peripheral dimension of the defect of the hollow cylinder. The method has the advantages that the measurement on the position and the dimension of the peripheral defect of the hollow cylinder is realized; higher precision is realized.

The invention discloses a wavelet neural network method for the nonlinear compensation of a capacitive weighing sensor, and the method comprises the following steps: 1, employing the nonlinear compensation principle of the capacitive weighing sensor, wherein the nonlinear compensation principle of the capacitive weighing sensor is mainly based on the basic links shown in figure 1; 2, setting the weight of an input load of the sensor as G, and setting the output voltage as u, wherein u=f(G), and G and u are in a nonlinear relation; 3, setting a relation: y=f1(u)=kG if a compensation link is connected in series behind a sensor. According to the invention, the method determines a nonlinear compensation network of the sensor through wavelet neural network training. The nonlinear compensation principle of the capacitive weighing sensor is introduced for analysis of the topological structure of the network, and a network parameter training and initialization method is given. The result indicates that the method is good in robustness, is high in network training speed, is high in precision, can achieve the online compensation, and is practical in a testing field.

The invention discloses a method for realizing real-time automatic compensation of the voltage and reactive power of a substation, wherein the characteristics of various reactive compensation and voltage optimization methods are analyzed according to the grid reactive power equilibrium principle and the reactive compensation rule; and in combination with the actual situations of a smart grid and an operating team, new automatic compensation manner and policy superior to the traditional 9-cell dynamic reactive compensation algorithm are proposed; thereby a foundation is laid for the construction of the smart grid and the implementation of an operating team, heavy operation, regulation and control integrated production manner.

The invention relates to a fiber laser dynamic ranging system fusing sweeping frequency and single frequency, and belongs to the technical field of laser ranging. In the system, a single-frequency laser and a frequency modulation laser are used to provide two different input lights, which are fused by a wavelength division multiplexer to reach a fiber-optic probe through a coupler; beams of two frequency bands are emitted and illuminated by the fiber-optic probe to the surface of a vibrating target, and reflected by the end face of the fiber-optic probe and the surface of the vibrating targetto form respective reference light and measuring light; the reference light and measuring light reach a photodetector through the coupler, the fiber amplifier and the wavelength division multiplexer,and a frequency sweeping ranging signal and a single frequency ranging signal are synchronously obtained at the photodetector; finally, in the system processing software, the time-frequency analysis speed judgment principle and the Doppler effect compensation principle are comprehensively utilized to fuse the frequency sweeping ranging signal and the single frequency ranging signal, thereby realizing accurate measurement of the absolute distance of the dynamic target.

The current sensor arrangement according to the compensation principle has a primary conductor, designed to generate a primary magnetic field dependent on a current to be measured flowing through it, a first secondary winding, designed to generate a first secondary magnetic field dependent on a first compensation current flowing through said winding, a second secondary winding designed to generate a second secondary magnetic field dependent on a second compensation current flowing through said winding, a magnetic field sensor designed to generate a measurement signal that represents a magnetic field detected by it; a magnetic core of soft magnetic material designed and arranged to magnetically interconnect a primary conductor, a first seconding winding, a second secondary winding, and a magnetic field sensor; a first evaluation circuit, downstream from the magnetic field sensor and upstream from the first secondary winding, and designed to generate a first compensation current corresponding to the measurement signal of the magnetic field sensor and feed the first secondary winding; and a second evaluation circuit, upstream from the second secondary winding and designed to generate a second compensation current corresponding to the first compensation current and feed the secondary winding. The magnetic field detected by the magnetic field sensor is the magnetic field in the magnetic core resulting from the superposition of the primary magnetic field, the first secondary magnetic field, and the second secondary magnetic field. The first compensation current and the second compensation current are adjusted by the first evaluation circuit and the second evaluation circuit such that the resulting magnetic field detected by the magnetic field sensor becomes zero. The second compensation current is greater or smaller than the first compensation current and represents the current to be measured flowing in the primary conductor.

The invention discloses an accurate comparison method for delta front sedimentary strata bottom surfaces at the same elevation. The accurate comparison method comprises the following steps: defining a plurality of isochronous surfaces in a delta front sedimentary strata section; analyzing the elevations of a single sand body bottom surface and the nearest isochronous surface under the control of the sedimentary compensation principle, and determining that sand bodies are the same or deposited contemporaneously if the elevations are the same; carrying out closed examination and planar examination. According to the method, the strata time of the single sand body level can be determined scientifically and reasonably; the division can be more accurate; the comparison result fits an underground geological condition better; the guiding significances in petroleum reservoir exploitation and recovery efficiency improvement are high.

The invention discloses a one-step method hot-bending bend device and process. The process comprises the steps that firstly, the theoretical length of a formed bend is calculated based on the compensation principle, feeding is carried out through an automatic plasma fire cutting machine or a sawing machine, a mechanical bevelling machine is used for beveling, and a short joint, the raw material of the bend, is manufactured; secondly, the circle center of a fast-mounting fixture and the center of a three-claw locating chuck are adjusted to be on the same line, feeding is carried out, a three-claw locating top is sleeved with one end of a steel pipe raw material in a sliding mode, a bore spine wheel is used for locking, the other end of the steel pipe raw material is placed in the fast-mounting fixture, an auxiliary push-pull oil cylinder is used for clamping, and then a fast-mounting claw bolt is used for locking; thirdly, a medium frequency heating device is used for heating, a hydraulic pulling device is used for pulling, meanwhile, a rocker arm is rotated to the specified angle, and bend heating and bending are completed; fourthly, the bend is offline and put into a storehouse after passing inspection. Key portions of an original process device are innovated, the original process device and procedures are changed, and therefore the aims of improving production efficiency and guaranteeing product quality are achieved.