115results about How to "Has engineering practical value" patented technology

The invention discloses a sub-module fault diagnosis method of a modular multilevel converter in the technical field of power transmission and distribution. According to the technical scheme, the method includes: firstly, performing fault feature analysis aiming at typical faults of sub-modules; secondly, configuring an SFDU (sub-module fault diagnosis unit) in an SMC (sub-module controller), and combining provided sub-module fault diagnosis indexes by the aid of capacitor voltage, bridge arm current and trigger signals at the moment so as to achieve diagnosis of faults of sub-module IGBT (insulated gate bipolar translator) short circuit, IGBT open circuit, FWD (freewheel diode) short circuit, capacitor failure and the like; and finally, adopting an exclusive method in a VBC (valve base controller) to achieve diagnosis of faults of sub-module FWD open circuit, capacitor open circuit failure, connection line open circuit and the like. The method has the advantages that diagnosis of sub-module faults is achieved on the base of software, additional measuring points are not added to an original control protection system, and the method is easy to implement, has quick and efficient sub-module fault diagnosis capability, and has coordination with other protection settings.

The invention discloses a method for analyzing wing structure aero-elasticity stability based on aerodynamic force uncertain order reduction. The method is based on unsteady aerodynamic force model order reduction method based on CFD technology; uncertainty of numerical calculation and aerodynamic parameters during aerodynamic force identification process is taken into comprehensive consideration and is uniformly quantified as an uncertain bounded interval noise sequence in an identification model; uncertain order reduction of the aerodynamic force model is realized by means of interval set membership identification algorithm; unsteady aerodynamic uncertain order reduction model based on CFD technology is established; mathematical model of uncertain aero-elasticity system of state space form is established coupled with structural motion equation; an effective method for predicting system robustness stability boundary from the prospective of section state matrix characteristic values. The aero-elasticity system uncertainty modeling thinking and stability boundary prediction technology provided by the invention gives consideration to calculation efficiency, analysis precise and system robustness.

Disclosed is a structural dynamics design method of the rotor of an aerial engine. Based on the characteristics of the working status of a high propulsion ratio aerial engine, the structural dynamics design method of the rotor of the aerial engine presents the concept of thermal modal to adapt to structural dynamics design of the rotor of the aerial engine under variable working conditions. The structural dynamics design method of the rotor of the aerial engine is characterized by optimizing the parameters of the rotor and bearings, enabling the thermal modal of a rotor system to avoid the modal of the rotor under the absolute rigidity of the bearings, meanwhile, giving play to the effects of a damper and enabling the rotor system to meet the requirements of vibration standards in the thermal modal. The structural dynamics design method of the rotor of the aerial engine comprises taking the margin between the modal of the rotor with elastic bearings and the modal of the rotor under the absolute rigidity of the bearings as optimized parameters, meanwhile giving play to the damping effects of the damper to meet the dynamics requirements of the rotor system. The structural dynamics design method of the rotor of the aerial engine changes the traditional design concept of design first and checking calculation later and performs active design of the dynamics characteristics of the rotor to achieve circulating design, thereby improving the working efficiency and having significant engineering practical value.

The invention discloses a redundant energy acquiring circuit for a power module. The power module comprises at least one power semiconductor device, a first capacitor C1 and a first bypass switch K1.The redundant energy acquiring circuit provided by the invention comprises a first Zener diode VD1, a second Zener diode VD2, a second switch K2, a first resistor R1, a second resistor R2, a second capacitor C2, a power supply board card and a control board card. The power supply board card acquires energy form the capacitor C1, supplies power for the control board card and charges the capacitor C2. The control board card controls the first bypass switch K1 to be switched on by triggering the switch K1. According to the scheme provided by the invention, when a fault occurs in the power supplyboard card, the capacitor C2 is charged through utilization of a breakdown characteristic of the first Zener diode, and a triggering command is provided for the switch K2 through utilization of the breakdown characteristic of the second Zener diode. The reliable bypass of the bypass switch is realized under the condition that the fault occurs in the power supply board card. The device running stopunder the condition that the fault occurs in the power supply board card of the power module is avoided. The scheme cost is low. The reliability is high.

The invention relates to a bionic galloping robot based on a connecting rod mechanism. The bionic galloping robot is characterized by concretely comprising a robot body (a), a track marching module (b), a galloping mechanism module (c) and a power module (d), wherein the robot body (a) consists of two quadrilateral pierced metal plates with the shape similar to a trapezoid and is used for fixing and installing other parts of the robot; the track marching module (b) mainly comprises two damping pins, a pair of damping springs and three pairs of crawler wheels; the galloping mechanism module (c) mainly comprises thighs, shanks, soles, foot connecting rods and shank connecting rods; and the power module (d) can be divided into two submodules i.e. a unidirectional transmission gear set and an automatic energy storage and release mechanism submodule. The robot can cross a higher obstacle and jump on a higher step on one hand and abandon a pure and complete simulation principle on the other hand. A jumping mode of the robot is combined with a machine track marching mode with convenience, rapidness and strong terrain adaptability, therefore, the bionic robot has the super strong obstacle-surmounting ability.

The invention discloses a method for calculating a random floating state of a ship on the basis of an STL (Stereo Lithography) model. The method comprises the following steps of calculating a midship draft TM, a heeling angle tangent value tan(Theta) and a trimming angle tangent value of the ship according to a conventional method; determining an equation of an inclined waterplane according to the midship draft, a heeling angle and a trimming angle; calculating a ship body displacement volume V under the waterplane and buoyancy coordinates (XB, YB, ZB); calculating barycentric coordinates (X'G, YG', Z'G) and buoyancy center coordinates (X'B, YB', ZB') of the ship under a fixed coordinate system; judging whether floating state equations meet a balance condition or not; performing three-parameter iterative calculation according to a fore draft, an aft draft and the heeling angle if the floating state equations do not meet the balance condition. The invention provides a three-parameter iterative method for calculating the floating state of the ship under any loading condition on the basis of the STL model, which has the features that the transverse inclination and longitudinal inclination of the ship can be calculated simultaneously, the method is suitable for any floating state of the ship, and the calculation precision is improved. The method disclosed by the invention has the advantages that the calculation quantity is reduced, the displacement volume and buoyancy center of the ship under any floating state are only calculated, and a program is strong and stable.

A composite electric energy quality disturbance signal quantitative analysis method comprises the following steps of a symbolizing the original electric energy quality disturbance signal timing sequence data; b positioning the beginning and ending moments of a disturbance signal; c analyzing the components of an electric energy quality disturbance signal. According to the present invention, a method of comparing the Euclidean distances in the cycle periods is adopted to detect the disturbance beginning and ending moments, and a new method of improving the fuzzy, overshoot and mode mixing problems in the conventional Hilbert-Huang transform (HHT) and in the disturbance waveform sudden change regions is established. The method of the present invention has a better decomposition effect on the dual composite electric energy quality disturbance signals, is similarly suitable for the single electric energy quality disturbance signal, facilitates managing the electric energy quality and analyzing the potential interference, and also has the reference meaning for the electric energy quality early stage early warning.

The invention discloses a pressure-proof proportion electromagnet based on an integrated type flux sleeve, which comprises a flux sleeve (5), a push rod (9), an armature (3) and the like, wherein a flux sleeve inner cavity (55) is arranged inside a front section (51) and a middle section (52) of the flux sleeve (5); an inner cavity end face (54) is formed at an interface of the flux sleeve inner cavity (55) and a rear section (53); the armature (3) is arranged inside the flux sleeve inner cavity (55); a limit piece (7) is arranged between a right end face (31) of the armature (3) and the inner cavity end face (54) of the flux sleeve (5); a radial operating air gap I (101) is formed by a gap between the side wall of the flux sleeve inner cavity (55) and the side wall of the armature (3); and an axial operating air gap II (102) is formed by a gap between the right end face (31) of the armature (3) and the inner cavity end face (54) of the flux sleeve (5). The proportion electromagnet has the characteristics of high pressure resistance, good force characteristic proportion performance, long effective stroke length and the like.

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 discloses a high voltage-resistant permanent magnet-shield high speed switching electromagnet. The high voltage-resistant permanent magnet-shield high speed switching electromagnet comprises a push rod (6) and a shell (1), an armature (8), a guide sleeve (4) and the like which are all magnetic conductors, wherein the outer surface of the guide sleeve (4) is provided with an annular trapezoidal groove (41); the bottom (412) in the centre of the annular trapezoidal groove (41) is provided with an annular permanent magnet (9); an inner cavity (40) of the guide sleeve (4) is provided with the armature (8) which is connected with the guide sleeve (4) in a sliding way; the push rod (6) is fixedly connected with the armature (8) after penetrating through the bottom (10) of the shell (1) and a trapezoidal guide sleeve channel (42); a returning spring (5) is arranged in the trapezoidal guide sleeve channel (42); and one end of the returning spring (5) is pressed against the shell (1) while the other end is pressed against the armature (8). The high voltage-resistant permanent magnet-shield high speed switching electromagnet has the characteristics of capacity of increasing output electromagnetic force and increasing response speed.

The invention relates to a breaststroke underwater advancing mechanism based on link mechanisms, which comprises a body, wherein a set of symmetrical link mechanism is respectively fixed at both sides of the body; each set of link mechanism comprises a structure that a thigh connecting bar and a leg connecting bar are articulated on the body and the other end of the leg connecting bar is articulated with a leg; the other end of a thigh is articulated with the leg and the hinge joint is close to the hinge joint of the leg connecting bar and the leg; one end of a stay wire is articulated on the thigh, the other end is connected with a root of a sole, the connecting point is arranged at the inner side of the hinge joint of the leg and the sole, the whole stay wire is arranged at the inner side of the leg, and the stay wire, the thigh, the leg and the sole form a parallelogram link mechanism; one end of a foot dorsiflexing rubber band is fixed on the leg, the other end is connected with an instep of the sole, and the connecting is arranged at the inner side of the hinge joint of the leg and the sole; the middle of the sole is articulated with one end of the leg, a heel part is articulated with the stay wire, and the instep is connected with the foot dorsiflexing rubber band. The invention has simple structure and control and easy implement.

A current converter module unit, a converter, a direct-current transmission system and a control method. In the converter module unit, the positive electrode of a first switch module (T1, D1) is connected to the positive electrode of a first energy storage element (C1), and the negative electrode of a second switch module (T2, D2) is connected to the negative electrode of the first energy storage element; the negative electrode of a diode (D6) is connected to the positive electrode of the first switch module, the positive electrode of the diode is respectively connected to the negative electrode of a second energy storage element (C2) and the negative electrode of a fourth switch module (T4, D4), the positive electrode of the fourth switch module is connected to the negative electrode of a third switch module (T3, D3), and the positive electrode of the second energy storage element is connected to the positive electrode of the third switch module; and the positive electrode of the third switch module is connected to the positive electrode of a fifth switch module (T5, D5), and the negative electrode of the fifth switch module is connected to the negative electrode of the second switch module. This structure can provide a favourable direct-current side fault ride-through performance, thereby overcoming the limitation and deficiency of structures such as a full-bridge module and a clamping double-module, and having better economical and technological performances.

The invention discloses a portable spin-free exchange relaxation atomic gyroscope structure. The portable spin-free exchange relaxation atomic gyroscope structure comprises an alkali metal gas chamberfixing seat, a non-magnetic electric heating base, a magnetic field compensation coil framework, a magnetic shielding cylinder, a detecting laser base, a detecting light splitting assembly, a pumpinglaser base, a pumping light beam expanding assembly, a pumping light stabilization light intensity assembly, a main structure, a positioning tool, and a supporting base. The alkali metal gas chamberfixing seat is used for fixing an alkali metal gas chamber. The non-magnetic electric heating base is used for clamping the oven. The detecting light splitting assembly adopts a connection fixing structure of the BS and the Glan prism. The pumping light beam expanding assembly is embedded in the ribs of the main structure. The pumping light stabilization light intensity assembly adopts a connection fixing structure of the PBS and the liquid crystal phase retarder. The main structure adopts a split cavity design combining a sinking type and a hanging type. The supporting base is used for fixingthe main structure and provides an installation reference for the gyroscope. The portable spin-free exchange relaxation atomic gyroscope structure is compact and symmetrical in structure, small in size and light in weight, and the optical assembly connection fixing structure is adopted, so that the optical performance stability is enhanced.

This is a method to detect strata shifting for bord. Two holes of the same diameter and height are drilled along any fracture surface of the bord, one is for detecting strata shifting and the other is for viewing of structure transform of strata to figure out the ratio of structure transform to total shifting.

The invention relates to a determination and adjustment method of support prestress values of transverse supports of a foundation pit under the condition near large load bias, the method includes thesteps that firstly, an earth pressure function of the edge wall of the foundation pit is calculated; and secondly, according to the earth pressure function, prestress values of all levels of the transverse supports are determined. According to the method for calculating the to-be-applied prestress values by the transverse supports at different levels in the foundation pit according to the condition of bias load distribution, engineering workers can quickly and efficiently adjust supporting parameters of the transverse supports of the foundation pit dynamically according to the bias load condition existing in the site, thus construction safety and reliability are improved, and the practical engineering value is achieved.

The invention discloses a three-phase inverter dead band time online adjustment and compensation method. By adjusting the dead band time online and modulating the dead band voltage into synthesized voltage of fundamental wave and third-harmonic square wave, the influence of harmonic voltage caused by a dead band on current is eliminated. The defect that the dead band time is close to zero when the current crosses zero is overcome. Moreover, current direction detection is not needed, calculation is simple, implementation is easy, and the method has engineering practical value.

The present invention relates to a photovoltaic power generation short-term power rolling prediction method based on a support vector machine algorithm. The generated power of a similar day and the current weather forecast of a predicated day are taken as the input amount of a prediction model, the photovoltaic power generation of the next day is predicated, after the next day is coming, the real output power of each predication point of the next day and the prediction power are continuously rolled forwards for comparison with the collection of the real power data, and when the predication points do not satisfy a given predication precision requirement, the real power of the current day and the real measurement weather data are taken as input data to establish a new PSO-SVM predication model so as to perform correction prediction of the power of the later-period predication points. The predication precision can be improved.

The invention discloses a transient electric energy quality signal analysis method based on high-frequency harmonic compensation iteration EMD, and the method comprises the following steps: 1), preprocessing a raw transient electric energy quality signal; 2), constructing a high-frequency compensation signal; 3), extracting an IMF component of the transient electric energy quality signal; 4), locating the starting and ending moments of transient disturbance; 5), carrying out the component analysis of the transient electric energy quality signal. The method carries out the decomposition of the IMF component, employs the HT transformation and an amplitude demodulation method for the decomposition of transient amplitude, transient frequency and phase of the signal, can analyzes the transient electric energy quality signal in real time, carries out the locating of the starting and ending moments of transient disturbance, and analyzes the harmonic component in the signal. The method can effectively carry out the locating and analysis of the transient electric energy quality disturbance signal, and provides reference data for the treatment of the electric energy quality, so as to guarantee the stable operation of a power system.

The invention discloses an opportunity-constrained coordination optimization method for electro-thermal interconnected integrated energy system. The method comprises the following steps of: firstly, based on the electricity-thermal interconnected integrated energy system model, taking into account the randomness and correlation of input variables, based on the primal-dual interior point method, the deterministic optimal energy flow is computed to obtain a set of optimal scheduling schemes, in which CLMCS (Correlation Latin Hypercube Sampling-Monte Carlo Simulation) method is adopted for solving probabilistic energy flow, Cornish-Fisher series fit the probability distribution of state variables. Finally, a heuristic algorithm is used to adjust the upper and lower bounds of the chance constraints, and a set of optimal scheduling schemes satisfying all the chance constraints is obtained by iterative computation. Analysis of examples verifies the effectiveness and practicability of the proposed method.

The invention relates to a low-vacuum absorption-type composite heat pump residual heat supply system based on an ultra-great-temperature-difference heat supply network, and belongs to the field of residual-heat-recovery-type cogeneration based on low-vacuum circulation water heating as well as absorption-type heat exchange. The low-vacuum absorption-type composite heat pump residual heat supply system comprises an absorption-type heat pump residual heat recovery device, a peak adjusting heater, a heat supply network ultra-great-temperature-difference heat exchange machine set as well as pipeline components. The low-vacuum absorption-type composite heat pump residual heat supply system is characterized by also comprising a direct dead steam recovery device as a water-based heat loading source of the heat supply network; a cold side inlet of the device is connected with a water return pipe of the heat supply network, and an outlet of the device is connected with a water inlet of an absorption-type heat pump heat supply network; a water outlet of the absorption-type heat pump heat supply network is connected with a water of a heat supply network of the peak adjusting heater; a water outlet of the heat supply network of the peak adjusting heater is connected with a water supply pipe of the heat supply network; dead steam enters the direct dead steam recovery device and the absorption-type heat pump evaporator. The low-vacuum absorption-type composite heat pump residual heat supply system provided by the invention is relatively higher in efficiency for thermal power plants than that in the conventional recovery mode for extracting residual heat from cooling water, can improve the dead steam residual heat utilization quantity by more than 1-2 times, and is especially suitable for central heat supply systems of middle and large sized turbosets.

The invention relates to a low vacuum ejector heat pump composite waste-heat heating supply system based on a huge temperature-difference heat supply network, and belongs to the field of waste-heat recovery type combined heat and power generation based on low vacuum circulation water heating and heat exchange of an ejector heat pump. The system is characterized by comprising an ejector heat pump waste-heat recovery device, a dead-steam direct recovery device, a pitch peak heater, a heat supply network huge temperature-difference heat exchange unit and a pipe fitting, wherein the dead steam is taken as a water-based load heat source of the heat supply network; a cold-side inlet of the dead steam direct recovery device is connected with a water return pipe of the heat supply network; an outlet is connected with a heat supply network water inlet of an ejector heat pump condenser; then the dead steam is sent to the pitch peak heater to be heated to the required temperature, and then exhausted out; at last, the dead steam is sent into the dead-steam direct recovery device, and an ejection port in the ejection section of the ejector heat pump. The system can be used for a thermal power plant with higher efficiency than the conventional recovery way that waste-heat is extracted from cooling water, the utilization amount of the dead-steam waste heat can be improved by more than 1-2 times, while the investment is only a part of that of an absorption heat pump.

The invention provides a DGS data format and IEEE standard format CDF interface conversion method. The method includes reading in a DGS-format file guided out by DIgSILENT software in a program, performing calculation and format finishing on data contained in an electric element module in the file, and generating a file meeting IEEE standard format CDF. The problem that data formats guided out by a DIgSILENT software power system after universal use is incompatible with data formats of conventional power system application software is solved, and the DGS data format and IEEE standard format CDF interface conversion method has high engineering practicability.