103results about How to "Good engineering practicability" patented technology

The invention relates to a spacecraft attitude integral sliding mode fault tolerance control method taking consideration of a performer fault and provides a robustness attitude active fault tolerance control method based on an integral sliding mode surface for problems of the performer fault, external disturbance and control moment amplitude limits in a spacecraft attitude control process. The method comprises steps that firstly, a spacecraft attitude dynamics model taking consideration of the performer fault and containing external disturbance is established; secondly, on the condition that a performer is not in fault, a designed nominal controller can guarantee system stability, and input saturation amplitude limits can be easily satisfied through adjusting controller parameters; lastly, the fault information is introduced to design an integral sliding mode controller, robustness of external disturbance and the performer fault can be effectively improved, system stability is analyzed on the basis of an Lyapunov method. The method is advantaged in that stability of the attitude control system is guaranteed when a spacecraft operating on orbit generates the performer fault, and relatively strong fault tolerance capability and external disturbance robustness are realized.

The invention provides a photovoltaic power prediction method based on a ground-based cloud chart. The method comprises the following steps: 1) pre-estimating the movement of a cloud cluster; 2) predicting irradiance on the ground; 3) establishing a comprehensive photoelectric conversion model; 4) and carrying out photovoltaic power prediction. A plurality of digital picture processing techniques are comprehensively applied, so that requirements of problems are highlighted, pertinency and practicality are high, and combined with the traditional statistical method, the photovoltaic power prediction method provides effective technical support and method reference for a photovoltaic power refinement prediction; models are established with multi-steps based on synthesizing of multi-factors; key links in the photovoltaic prediction field are all included in the description of the method, so that universality and robustness are high; in order to combine concrete scenes and application objects used during usage, adjustment parameters are reserved in some links, so that operation is convenient and prediction effect is guaranteed.

The invention discloses a hybrid energy storage system and a wind power generation power smooth control method. Firstly, a frequency spectrum of a wind power signal is obtained through a quick Fourier method, and amplitude-frequency characteristics of wind output power are analyzed; then, wind power is decomposed in multiple scales through an empirical mode decomposition method and then reconstructed into wind farm expected grid-connection power and high-frequency, mediate-frequency and low-frequency wind power fluctuation power; the power is distributed according to the capacity of a super-capacitor Soc, correspondingly adjusted and absorbs high-frequency, mediate-frequency and low-frequency fluctuation signal power through the super-capacitor, a storage battery and stored compressed air energy; when the output power of a wind farm is smaller than an expected grid-connection power signal, a hybrid energy storage system composed of the super-capacitor, the storage battery and an CAES is controlled to discharge through a model algorithm; when the output power of the wind farm is larger than expected grid-connection power, the hybrid energy storage system composed of the super-capacitor, the storage battery and the CAES is controlled to charge through the model algorithm. The hybrid energy storage system and the wind power generation power smooth control method improve safety and economic efficiency of grid-connection operation.

The invention provides a cloud cluster movement estimation method facing to photovoltaic power prediction. The cloud cluster movement estimation method for the photovoltaic power prediction comprises the following steps: preprocessing an image of a ground-based cloud picture; thresholding the ground-based cloud picture; detecting and marking a cloud cluster and extracting center of mass of the cloud cluster; and estimating moving speed and direction of the cloud cluster. By the cloud cluster movement estimation method for the photovoltaic power prediction, each cluster in a time sequence image is tracked and studied to determine the moving speed and direction of the cloud cluster in the future, so that the cloud cluster movement in the future is estimated, and an important data source is provided for minute-grade power prediction within a super-short period of 0-4 hours for a photovoltaic power station.

The present invention relates to a radar application-based target RCS real-time evaluation method. According to the method, firstly, echo signals are subjected to AD sampling and digital signal processing, and then original track points are outputted. Secondly, original track points are subjected to coagulation treatment and coagulated track points are subjected to flight track treatment. In thisway, track points are obtained. Thirdly, the amplitude of track points is subjected to distance and STC correction, and the amplitude value of an outputted flight track is subjected to real-time meanstatistics. According to the region of the statistical result of the amplitude mean of a target flight track, the RCS value of the target is estimated. The method can be applied to the RCS real-time evaluation of a to-be-tested target based on radar equipment and is applicable in engineering application conditions.

The invention discloses a spacecraft attitude output feedback tracking control method giving consideration to limited control. Aiming at a problem that the angular speed information cannot be measured directly when a spacecraft works in orbit, and a problem of external disturbance and a problem of limited control, the invention proposes an attitude tracking output feedback controller design method, which has no angular speed information feedback and meets the requirement of limited control input. The method comprises the following steps: firstly building a spacecraft attitude tracking error dynamical model comprising external disturbance; secondly designing a dynamic angular velocity observer; and finally designing an output feedback control method meeting the requirement of limited control input based on angular velocity estimation information through employing the characteristics of a saturation function. The method achieves the independent design of the angular velocity observer of a spacecraft attitude control system and the decoupling of the controller, can achieve the effective online estimation of the angular velocity information, is robust for the external disturbance and limited input saturation, and is suitable for a moving object attitude tracking control system when a spacecraft works in orbit.

The invention discloses a dynamic equivalence method of an alternating-current-direct-current serial-parallel large power system based on engineering application, and belongs to the field of electric transformation and distribution. The method of the alternating-current-direct-current serial-parallel large power system based on the engineering application comprises dividing a power grid to be analysed into two parts including an external power grid and an internal power grid, detailedly imitating a 500 kV power grid inside an area, carrying out equivalence simplification on the external power grid and an internal low voltage power grid, obtaining an external simplified power grid from the external power grid through an equivalence generator by using a dynamic equivalence method based on experience, obtaining a final internal simplified power grid by carrying out equivalence simplification on the internal low voltage power grid by using the dynamic equivalence method based on physical equivalent, respectively checking equivalence effects after the external power grid and the internal power grid are in dynamic equivalence, and checking effectiveness of the entire dynamic equivalence principle and method through comparing dynamic response curves of a simplified power grid and an actual power grid in the same fault. The method of the alternating-current-direct-current serial-parallel large power system based on the engineering application has the advantages of reducing quantity of equivalence system state and the number of differential equation, improving system analysis computational efficiency, and being capable of being widely used for analytical calculation of a serial-parallel large power grid and used in the field of dispatching management of power grids.

The invention discloses an array antenna phase-only transformation beam shaping method, which implements beam shaping with different radiation requirements only by phase weighting under a condition that the power keeps unchanged. The method comprises the following steps: obtaining element excitations corresponding to directional diagrams which meet respective radiation performance requirements by employing an improved iterative Fourier algorithm, and retaining each unit phase excitation value corresponding to each type of beams therein; and then, finding a common unit excitation current value by employing an improved convex optimization algorithm to meet higher radiation performance requirements of each directional diagram, such as a smaller main lobe wave in each directional diagram, a lower side-lobe level value and the like. A hybrid optimization algorithm disclosed by the invention effectively combines the iterative Fourier algorithm and the convex optimization algorithm, does not need parameter adjustment and has the characteristics of strong robustness, fast computation speed and high precision, thereby finally implementing simplification of a feed network; and only through a phase excitation change of array elements, the beam shaping with the different radiation performance requirements is implemented.

The invention discloses an efficient recognition method for the flight control signal of a low-altitude, slow-speed and small unmanned aerial vehicle. The method comprises the steps of step 1, carrying out primary detection on a flight control link signal; step 2, extracting key features, and constructing a target feature database; step 3, carrying out feature fusion and optimization; step 4, analyzing the signal according to the fused optimized features so as to obtain the type, the frame format and the keyword segment of the signal, and storing the obtained analysis result into the target feature database; step 5, according to a learning algorithm based on a neural network, realizing the accurate classification and recognition of the target, and obtaining a correct recognition result. According to the method, the recognition problem for the flight control signals of low-altitude, slow-speed and small unmanned aerial vehicles can be solved. Therefore, the recognition, management and control for a specific airspace can be realized. Meanwhile, the high-efficiency early warning and defense effect for various low-altitude, slow-speed and small unmanned aerial vehicles which have illegally intruded into secret-related and sensitive airspaces can be realized. The method is higher in correct recognition rate, lower in calculated amount, higher in processing efficiency and strong in applicability.

The invention discloses a core loading method of pressurized water reactor nuclear power plant first cycle. A first cycle core adopts a fuel assembly with 4-6 different enrichment degrees, a high leakage loading mode is adopted, and core reactivity inhibition and power distribution control are carried out by simultaneously adopting borosilicate glass solid inflammable poison rods and integrated gadolinium-supported fuel rods. The method greatly prolongs the cycle length of the first cycle core, adopts two solid inflammable poisons to avoid the contradiction of occupation of control rod guiding tubes due to use of too much borosilicate glass and avoid negative influences of unfavorable axial power distribution caused by use of too many integrated gadolinium solid inflammable poisons on running control, makes the core design be flexible, makes the power distribution flattening of the core be easy, has good engineering practicality and design flexibility, and can well realize the economy and safety of the power plant.

The invention discloses a low-energy planetoid precise track transfer detection method for complex constraints, and belongs to the technical field of aerospace. The method comprises the steps that firstly, various complex non-consistent strong coupling constraints needing to be met by a track detection design task are determined, and the mapping relation between track design parameters and the various complex non-consistent strong coupling constraints is built; under a mass center rotating coordinate system, a detector dynamics equation is built; an initial value is provided through the builtlinear detector dynamics equation, a precise quasi periodicity track under an ephemeris model is obtained by adopting a nonlinear dimension reduction method and second-order differential coercion; onthe basis of the precise quasi periodicity track under the ephemeris model, a quasi manifold disturbance method is adopted for optimizing the obtained transfer track initial value; for the various complex non-consistent strong coupling constraints, the obtained transfer track initial value is corrected, and the precise low-energy transfer track is obtained. The method has the advantages of being high in efficiency, good in convergence and low in energy needed by transfer.

The invention provides a cabin cross section circumference measuring device and method based on the non-contact profiling method, and belongs to the technical field of manufacturing and precision measurement. The cabin cross section circumference measuring device comprises a system of a part to be measured, a reference coordinate motor system, a follow-up rocker system and a data collecting, analyzing and processing system. The follow-up rocker system comprises a displacement sensor, a rocker arm, a ball screw, a sliding block, a follow-up servo motor and a counter weight. The data collecting, analyzing and processing system comprises a signal transformer, an analog-to-digital converter, a motion controller and a digital-to-analog converter. The motor drives a rocker arm system to rotate by a circle, the displacement sensor records the coordinate positions of all points to be measured by the adoption of the non-contact method, the shape of the part to be measured is profiled, and the circumference of the part to be measured is calculated. The cabin cross section circumference measuring device and method based on the non-contact profiling method can achieve higher measurement accuracy and cannot scratch the part to be measured at all.

The invention provides a pedestrian mask wearing real-time detection method based on deep learning. The pedestrian mask wearing real-time detection method comprises the following steps: S1, establishing a robust backbone network; S2, carrying out the multi-scale training; S3, performing model compression; S4, performing model optimization. According to the method provided by the invention, more labor overhead cost, and calculation cost and time overhead cost of the small hardware storage device are considered. Whether a pedestrian wears the mask or not can be judged more quickly, and good engineering practicability is achieved.

The invention relates to a method for measuring a steel strut axial force by utilizing an adhered steel sheet, and the method comprises the following steps: (1) designing a standard steel sheet and marking the optimal tensioning state frequency f and standard calculating coefficient K of the standard steel sheet; (2) choosing the required adhered steel sheet according to the marking result, installing the chosen adhered steel sheet on a steel strut at an unstressed state before installing the steel strut, then adjusting the adhered steel sheet to the optimal tensioning state, and recording the calculating coefficient K of the adhered steel sheet at the optimal tensioning state; and (3) bearing an axial pressure by the steel strut in the use process of the steel strut, measuring the frequency value fi of the adhered steel sheet at such a state, and according to an axial force formula shown in the specification, calculating and acquiring the axial force F of the steel strut, wherein E represents a steel strut elastic modulus and A represents a cross sectional area of the steel strut.