19 results about "Wave processes" patented technology

The invention relates to a double-end traveling wave fault location method based on weighted Minkowski distance and cubic spline interpolation. The method comprises the following steps: performing smooth fitting expansion processing on fault waveform data W through cubic spline interpolation; training a traveling wave head clipping model, and automatically positioning and clipping a wave head region Wcs; respectively recording the Wcs after the traveling wave processing at the two ends as Wa and Wb, translating one waveform, and calculating a weighted Minkowski distance dist; when dist is minimum, the translation amount is the time difference delta t when the traveling wave reaches the two ends for the first time. Through cubic spline interpolation, under the condition of low sampling rate, smooth fitting expansion is carried out on the signal waveform, the actual error range is obviously reduced, and the positioning precision is improved; according to the method, the weight of the distance near the fault moment is increased, the effect of highlighting the fault point is achieved, for the noisy waveform, noise reduction and other operations which can change the original waveform can be not carried out, the time difference delta t of the wave heads of the two fault traveling waves can be calculated, and the measurement error existing in the practice of the prior art is reduced.

The invention belongs to the technical field of distribution network fault diagnosis, and particularly relates to a device and method with a fault accurate positioning function. The main control module is respectively connected with the fault interval judgment module, the traveling wave processing module, the GPS synchronization module and the main station reporting module and establishes a data channel; the fault interval judgment module provides a starting signal and an interval range for the traveling wave processing module and provides a power frequency recording file for the master station reporting module; the traveling wave processing module collects and processes traveling wave current and voltage signals; the GPS synchronization module provides a high-precision pulse signal and is used for recalibrating time; and the master station reporting module carries out fault interval precision and accurate positioning according to the received fault information in combination with the power frequency recording file and the traveling wave recording file. According to the invention, through dual-signal acquisition of traveling wave voltage and current signals, the method adapts to a multi-fault scene, and a current and voltage traveling wave comprehensive research and judgment method is adopted, so that the problem that a blind area exists at a current traveling wave interconnection switch is solved, and the problem of voltage traveling wave length line attenuation is also solved.

The invention discloses a construction method and system for a long-period sea wave height time sequence process at a berth in a port. The method comprises the following steps: constructing a wave propagation model; on the basis of actual measurement or reanalysis of wind wave length time series data, a typical-order wave spectrum process curve at the boundary of the model is obtained so as to drive the wave propagation model; on the basis of the driven wave propagation model, wave parameters at the berth are obtained, and the nonlinear fitting relation between the wave parameters at the boundary and the wave height at the berth is obtained through calculation; and acquiring long-time-sequence wave parameters at the boundary, and based on the long-time-sequence wave parameters at the boundary, obtaining gravity wave short-wave and low-frequency long-wave processes of the long-time-sequence sea waves at the berth through the nonlinear fitting relationship. According to the method, the long-time-sequence process of low-frequency long waves and gravity short waves at any berth of a harbor area can be rapidly achieved, dynamic load conditions influencing ship movement at the berth are provided, and basic wave conditions are provided for evaluating the number of days of ship operation loss.

The application discloses a kind of flexible direct current transmission line fault transient electrical quantity determination methods, comprising: according to the circuit parameter of MMC converter station, construct MMC equivalent circuit when inter-pole short circuit;According to the transmission line parameter obtained, establish the equivalent model of two-port of direct current transmission line under complex frequency domain;According to the equivalent circuit of MMC when inter-pole short circuit and the equivalent model of two-port of direct current transmission line, obtain the expression of direct current fault transient under complex frequency domain;The expression of direct current fault transient under complex frequency domain is carried out Laplace transformation to obtain time domain response, the whole trend of transient process after fault can be given more accurately by the application.The calculation process is simple, avoids the complicated modeling simulation process in traditional simulation method.Meanwhile, it can well reflect the occurrence wave process when overhead line fails.The method can accurately express the overall development trend of the fault current flowing through the protection installation before the converter station is locked after the fault occurs, and has a positive significance for the fault current suppression and protection setting design of MMC-HVDC system.

The application discloses a construction method and system for long-period sea wave height time sequence process at a berth in a port, and the method comprises the following steps: constructing a wave propagation model; obtaining a wave spectrum process curve of a typical group of a boundary of the model based on measured or reanalyzed long-time sequence wind wave data, so as to drive the wave propagation model; obtaining wave parameters at the berth based on the driven wave propagation model, and calculating a nonlinear fitting relationship between the wave parameters at the boundary and the sea wave height at the berth; and obtaining long-time sequence wave parameters at the boundary, and obtaining the gravity wave short wave and low-frequency long wave process of the long-time sequence sea wave at the berth based on the nonlinear fitting relationship and the long-time sequence wave parameters at the boundary. The application can quickly realize the long-time sequence process of low-frequency long waves and gravity short waves at any berth in a port, provide dynamic load conditions of the berth affecting ship movement, and provide basic wave conditions for evaluating ship operation loss days.

The invention discloses a cable distribution parameter model construction and wave process analysis method, and relates to the technical field of the power industry, and the method comprises the steps: analyzing a cable structure to determine the hierarchy of the cable structure; constructing a distributed parameter model composed of unit length resistance, inductance, conductance and capacitance according to the ratio of the wavelength of the traveling wave to the length of the cable; an equation set is listed based on the Kirchhoff's law, and a transmission line partial differential equation describing the electromagnetic transmission characteristics of the cable is deduced; a refraction and reflection rule of traveling waves in a cable is analyzed, voltage and current refraction and reflection coefficients are deduced to determine traveling wave propagation behaviors, and in addition, time domain traveling wave fault distance measurement, fault distance measurement based on an improved head end reflection coefficient spectrum and insulation defect online monitoring based on active signal injection can be achieved in an extending mode. The method can eliminate the periodic distortion of the traditional frequency domain reflection spectrum, improves the fault distance measurement precision, achieves the real-time monitoring of the insulation state, and guarantees the safe and stable operation of the cable.

The invention discloses a wave dynamic weather typing method based on environmental field feature extraction, and belongs to the technical field of coast and ocean engineering. Comprising the following steps: acquiring n-year time sequence historical data of wave elements of a certain station, and acquiring n-year time sequence historical data of a wind field and a sea level air pressure field near the station; identifying independent wave events from the time sequence wave height sequence based on a five-day time window, and screening relatively strong independent wave events as to-be-classified events according to a threshold method; the regional correlation between the wind speed and the independent wave process peak element under different time lag conditions is explored to determine the time domain and the space domain of the wind field and the sea level air pressure field for classification; and inputting the determined wind field and the sea level air pressure field into an SOM + K-means clustering algorithm to obtain a weather typing result of the independent wave event. According to the method, the blindness of initial clustering center selection of the K-means clustering algorithm is improved, and the method has the advantages of short convergence time, high result stability and the like.

A shock wave simulation generating device disclosed by the present invention comprises a shell, a power assembly, an impact assembly and a closed cavity are arranged in the shell, the power assembly is connected with the impact assembly, the power assembly can drive the impact assembly to reciprocate, the impact assembly is connected with the closed cavity, and the closed cavity is connected with the power assembly. And the impact assembly enables the volume of the closed cavity to be increased or decreased in the reciprocating motion process, so that positive pressure or negative pressure is generated in the closed cavity to simulate the impact wave process generated by explosion. The shock wave simulation device can simulate the whole process of shock wave generation through one-button operation, has the advantages of high output precision and small human influence factor, and overcomes the defects of low precision and large misoperation due to the fact that an existing shock wave simulation device adopts manual compression of a closed cavity.

The invention discloses a relay protection equipment simulation system based on virtual digitization, and the system comprises a fault scene construction unit which is used for simulating various faults, and setting the fault occurrence time, position, duration time and fault type; the power system model building unit is used for simulating the dynamic change of electromagnetic characteristics during the fault occurrence period by using a transformer model; simulating the wave process and transient characteristics of the power transmission line and the distribution rule of voltage and current along the line by using the power transmission line model; simulating the dynamic change of the load by using the load model; the calculation unit is used for dividing a power grid into discrete networks based on a time domain finite difference algorithm of a node voltage method and carrying out discretization processing on time and space; and the whole process fault simulation unit simulates the whole process of fault occurrence in stages. According to the system, a comprehensive, accurate and dynamic simulation environment can be provided for relay protection equipment testing and power system fault analysis, and the safety and reliability of a power system can be improved.

The invention belongs to the technical field of circuit simulation analysis, and discloses a mutual inductance circuit modeling method and a related device, and the method comprises the steps: carrying out the partitioning of an inductor, enabling the inductance of an inductor element after partitioning to be complete during the partitioning of the inductor, and enabling the number of the inductor elements after partitioning to be minimum under the condition that the number of the inductors of the inductor elements after partitioning meets the requirements of a computer memory; revising the inductance value of the inductance element so as to delete overlapped inductance values generated in all inductance of the partitioned inductance element; a simulation circuit is established by using the inductance element after the inductance value is revised, and when the simulation circuit is established by the inductance element, the inductance element is connected in a manner that the out-of-circuit characteristics of the inductance element before and after partitioning are kept consistent. According to the method, a large inductance element in the circuit is decomposed into a plurality of small inductance elements, on the premise that the result is not changed, the problem that a computer memory is limited is solved, and the efficiency and feasibility of large-scale mutual inductance circuit simulation in the overvoltage wave process and under other conditions are improved.

The application relates to the technical field of wind power, and is a short-term wind power prediction method considering wave fluctuation process division, which has the characteristics that wave fluctuation characteristics can be extracted according to wind turbine output characteristic analysis results and a wind speed-power physical conversion model, then an improved K-means clustering method for wind power prediction is proposed, and based on the classification results, an abnormal data processing model and a short-term wind power prediction model under different wave fluctuation processes are established. Simulation calculation verifies that the prediction method is scientific and reasonable, the prediction process is simple, the prediction precision is high, the physical meaning is clear, the prediction result is effective, and the practicability is high.

This invention discloses a virtual digital relay protection equipment simulation system, comprising: a fault scenario construction unit, used to simulate various faults and set the time, location, duration, and type of fault occurrence; a power system model construction unit, comprising: using a transformer model to simulate the dynamic changes of electromagnetic characteristics during fault occurrence; using a transmission line model to simulate the wave process, transient characteristics, and voltage and current distribution along the transmission line; and using a load model to simulate the dynamic changes of the load; a calculation unit, which, based on the nodal voltage method and the finite-difference time-domain algorithm, divides the power grid into discrete networks and discretizes time and space; and a full-process fault simulation unit, which simulates the entire fault occurrence process in stages. This system provides a comprehensive, accurate, and dynamic simulation environment for relay protection equipment testing and power system fault analysis, thereby improving the safety and reliability of the power system.

An extreme wind wave current coupling under floating photovoltaic power response test device, including environment simulation system, semi-submersible photovoltaic platform system, mooring system and data measurement and acquisition system. The environment simulation system simulates the coupling effect of wind, wave and flow composite load. The semi-submersible photovoltaic platform system contains photovoltaic component model constructed according to the predetermined scale ratio and the float component providing support and buoyancy for the photovoltaic component model, which can truly reflect the wind load effect of photovoltaic structure and the platform hydrodynamic response. In the data measurement and acquisition system, the cooperation of dynamic visual sensor and pressure sensor realizes the synchronous and accurate observation and measurement of the six degrees of freedom motion of the platform, the mooring tension, especially the deck wave process and the slamming load. The invention solves the problem of fine observation of traditional test in complex load simulation and extreme sea state, and provides a reliable test means for the safety design and performance evaluation of deep sea floating photovoltaic platform.

A two-dimensional flow structure description method for water waves, the fluctuation form of the water waves is traveling waves or similar traveling waves, and the method comprises the following steps: integrally and horizontally translating flow field data of a flow field where the water waves are located at different moments within a target time range, so that horizontal coordinates of lower flow field data corresponding to the same wave surface feature point are the same; forming flow field data corresponding to the fixed fluctuation area; a section of flow field data in the flow field data is intercepted to serve as description initial data, intercepted range parameters comprise a description horizontal range and a description time range, and a description area is limited in the description initial data; performing interpolation calculation on the description initial data to obtain fine flow field data, and eliminating invalid data in the fine flow field data to form effective flow field data; according to effective flow field data, a Lyapunov exponent field in a calculation description time range is described, change characteristics of a flow structure are described, and quantitative description is carried out on flow field evolution in a downlink wave or similar traveling wave process under a free surface condition in a period of time and a space range.

The utility model relates to the field of metal corrugated pipe processing equipment, and discloses a prestress metal corrugated pipe automatic forming machine which comprises a rack, a wave pressing structure, a forming structure and a cutting structure, the wave pressing structure, the forming structure and the cutting structure are all arranged on the upper end face of the rack, and the wave pressing structure comprises a feeding motor and a wave pressing box. The output end of the feeding motor is connected with the wave pressing box through a gear, the forming structure comprises a driving winding motor, a mounting plate, a winding main shaft, a first-stage adjuster, a second-stage adjuster and a third-stage adjuster, and the cutting structure comprises a sliding rail, a second adjusting seat, a first air cylinder, a progress adjusting seat, a second air cylinder and a cutting motor. According to the utility model, the wave pressing structure can be used for processing a wider steel belt, so that the steel belt can stably move in the wave pressing process, the stress is uniform in the process of moving from the wave pressing box to the winding main shaft, the forming stability is ensured, meanwhile, the automation degree is high, manual intervention is not needed, and the processing is efficient.

The application provides a wave process calculation method considering the corrugated aluminum sheath structure of a high-voltage cable, and the steps include: deducing the inner radius formula of the corrugated aluminum sheath of the high-voltage cable according to the geometric characteristics of the corrugated aluminum sheath; using the average geometric radius technology to equivalently convert the corrugated aluminum sheath into a uniform cylindrical shell; using a sine function to fit the corrugation of the actual corrugated aluminum sheath; solving the effective length of the equivalent uniform cylindrical shell; deducing the conductor impedance calculation approximate formula based on the effective length and the equivalent uniform cylindrical shell structure; deducing the admittance calculation formula based on the actual corrugated aluminum sheath structure of the high-voltage cable; calculating the cable wave transmission process characteristic parameters considering the corrugated aluminum sheath structure based on the above formula; and verifying the calculation results by building a low-voltage pulse verification test loop. The application is not only suitable for the distributed parameter equivalent circuit calculation of the corrugated aluminum sheath power cable of different sizes, voltage grades and lengths, but also can improve the electromagnetic transient simulation accuracy of the cable.

The invention relates to a floating photovoltaic dynamic response test device under an extreme wind wave flow coupling effect. The floating photovoltaic dynamic response test device comprises an environment simulation system, a semi-submersible photovoltaic platform system, a mooring system and a data measurement and acquisition system, the environment simulation system simulates the coupling effect of wind, wave and flow composite loads. The semi-submersible photovoltaic platform system comprises a photovoltaic module model constructed according to a predetermined scale ratio and a floating body module for providing support and buoyancy for the photovoltaic module model, and can truly reflect the wind load effect of a photovoltaic structure and the hydrodynamic response of the platform. And in the data measurement and acquisition system, a dynamic visual sensor is matched with a pressure sensor, so that synchronous and accurate observation and measurement of six-degree-of-freedom motion of the platform, mooring tension, particularly a deck wave rising process and a slamming load are realized. According to the invention, the problem of the traditional test in the aspects of complex load simulation and deck wave fine observation under extreme sea conditions is solved, and a reliable test means is provided for the safety design and performance evaluation of a deep and far sea floating photovoltaic platform.

The invention relates to a direct current power transmission system-oriented fault initial wave process analysis method and equipment. The method comprises the following steps of: calculating time delay of a propagation function minimum phase system; processing the rational fraction of the propagation function and the rational fraction of the wave impedance by adopting a discrete recursion convolution method in combination with the time delay of the minimum phase system of the propagation function to obtain a low-order dispersion equivalent voltage source recursion, and integrating into a high-order dispersion equivalent voltage source recursion of the propagation function according to a linear time-invariant system superposition theorem; a wave impedance equivalent voltage source and transmission line equivalent resistance are obtained by combining the recursion law of the RC parallel network; constructing a direct-current transmission broadband Bergeron equivalent calculation circuit; and analyzing the fault initial wave process by using a direct-current transmission broadband Bergeron equivalent calculation circuit. The method can be suitable for any sampling rate, transition resistance, fault position and fault type, and good precision is kept within 10-20 ms after disturbance occurs.

The application discloses a kind of based on decoupling matrix of DC transmission line fault characteristic analysis method, first equivalent DC transmission system is the circuit with unchangeable topological structure, using superposition principle will fault network equivalent pre-fault steady current and post-fault fault component network, deduce post-fault current wave analytical expression, based on the pole mode transformation of bipolar decoupling matrix, deduce the DC transmission line fault characteristic of the wave process scale of decoupled DC line in mode domain.The decoupling matrix and fault characteristic analysis method suitable for UHVDC transmission line proposed in the application, compared with traditional DC fault wave analysis method, considers the non-ideal transmission characteristics of wave at the boundary of converter, has higher analysis and calculation precision, has the advantages of simple and easy to operate, clear and so on, and has great popularization significance.