9 results about "Acceleration coefficient" patented technology

The invention discloses a permanent magnet synchronous motor parameter optimization method based on an improved moth flame particle swarm algorithm. In order to solve the problems that a traditional PID controller is difficult in parameter setting, poor in adaptability, insufficient in control precision and the like under complex working conditions, in the strategy, an MFPSO algorithm fuses a particle swarm optimization (PSO) algorithm and a moth flame optimization (MFO) algorithm. An adaptive inertia weight and Gaussian mutation strategy is introduced, so that particles can focus on local fine search, and the speed of convergence to an optimal solution is accelerated. The optimization capacity of the algorithm in different stages is enhanced by adopting a nonlinear acceleration coefficient, and local optimum is effectively avoided. A grouping evolution mechanism is designed to promote intra-group information sharing and inter-group competition, the population diversity is enriched, and the ability of the algorithm to jump out of a local optimal solution is further improved. The fuzzy PID controller based on the MFPSO algorithm optimization parameters can better meet the requirements of high-performance control of permanent magnet synchronous motors in different fields, and has application prospects and economic values.

The application belongs to the technical field of aircraft brake control, and discloses an aircraft anti-skid brake control parameter optimization method based on an improved particle swarm algorithm. The method comprises the following steps: establishing a mathematical model of an aircraft brake system and determining target parameters; obtaining model parameters of the mathematical model of the aircraft brake system; initializing parameters of the improved particle swarm algorithm; adjusting inertia weight and acceleration coefficient of the particle swarm algorithm by adopting a second-order oscillation link; updating and iterating particles; performing boundary crossing processing and anti-skid processing on the particles after updating and iteration; comparing the fitness value of each particle after updating with a current optimal fitness value, and updating the optimal value; performing a differential mutation operation on the particles, and updating the optimal value; and stopping until the maximum iteration number is reached. The method solves the problem that in the field of aircraft brakes, optimal brake control law parameters are difficult to select in order to achieve short-distance and high-efficiency braking.

The invention discloses an airplane electrical return network failure bottom event index measuring and calculating method and computer equipment. The method comprises the following steps: identifying three types of core bottom events of airplane electrical return network failure; a failure rate measuring and calculating method is determined for each type of bottom events, cable failure is calculated through a query data manual method, structure disconnection failure is calculated through finite element simulation in combination with a fatigue theory, and degradation data is obtained through an accelerated test method for electrical lap joint corrosion failure to establish a failure rate measuring and calculating model; manufacturing an electric lap joint structure test piece by adopting materials, processes and configurations which are equivalent to those of an installed product; and carrying out an acceleration test on the test piece to obtain failure data under each stress step, extrapolating through the life distribution model to obtain the characteristic life under each stress step, obtaining an acceleration coefficient through a regression algorithm by utilizing an accelerated life model, and calculating according to the acceleration coefficient to obtain the MTBF and failure rate of the lap joint assembly. The method can greatly improve the precision and confidence of failure rate measurement and calculation.

The application belongs to the technical field of composite material durability and reliability evaluation, and discloses a composite material equivalent acceleration and life prediction method and system under a polar multi-field coupling environment. The application constructs a natural environment spectrum of a service environment; determines key environmental factors based on the environment spectrum and a damage mechanism, designs and combines a moisture absorption module, a freeze-thaw module, a low-temperature freezing module and an ultraviolet radiation module to form an acceleration test spectrum; performs a multi-cycle accelerated aging test on a sample according to the spectrum, and synchronously applies a mechanical load; tests the performance of the sample after aging by using a high-throughput platform, and obtains attenuation data; based on the equivalent relationship between the data and the acceleration spectrum, a life prediction model is established by fitting a residual strength model and calculating an acceleration coefficient, so as to realize the life prediction of the composite material under the multi-field coupling environment. The application systematically expounds the compilation method of the multi-factor equivalent environment acceleration test spectrum of the composite material in the marine environment, and lays a foundation for the related research on the life prediction of the composite material in the polar low-temperature environment.

A method for predicting the aging decay of a gas diffusion layer based on a combination of offline and online methods is provided. [Solution] The gas diffusion layer and initial performance to be predicted are obtained, and offline and online cycle stand tests of durability aging decay are conducted respectively, and the test times are recorded. After completion, the deterioration performance of the gas diffusion layer to be predicted is collected, and offline performance tests are conducted one by one on samples after the offline aging test and on samples obtained by disassembling the test stack, and the average performance of the gas diffusion layer to be predicted at that time is obtained. A set of aging decay acceleration coefficients from the offline durability test and the online cycle stand durability test are calculated and obtained, and the coefficients are added to calculate the average to obtain a final combination of acceleration coefficients, and then added and averaged to obtain the final acceleration coefficient.

This invention provides a method for evaluating the long-term stability of vibration-damping elastomers under multi-mode coupling environments. The method includes sample preparation, test setup, test parameter setting, collaborative detection, damage source tracing, accelerated calculation, and life prediction. Collaborative detection includes macroscopic and microscopic detection; damage source tracing involves determining the contribution ratio of each component; accelerated calculation yields the total acceleration coefficient; and life prediction is based on the acceleration coefficient, providing a scientific basis for formulation optimization, structural design, and engineering applications. The method for evaluating the long-term stability of vibration-damping elastomers under multi-mode coupling environments provided by this invention realistically simulates the synergistic effect of damp heat and dynamic load, achieving rapid and accurate life prediction.

Disclosed are a parallel accelerated test method and apparatus that separately applies multiple sensitive stresses to multiple components. Sensitive stress types of different product components are determined respectively, and accelerated test stress values of the different product components are determined respectively based on the sensitive stress types. The overall product acceleration coefficient is determined, the accelerated test stress values of different product components are corrected based on the overall product acceleration coefficient, and the multi-box coordinated deployment scheme is determined based on the sensitive stress types of different product components and the corrected stress values in accelerated test. Based on an accelerated test confidence level and product failure count threshold, a target accelerated test scheme is determined from candidate accelerated test schemes. Under the multi-box coordinated deployment scheme, the target accelerated test scheme is executed in parallel on different product components to obtain a product life evaluation result.

The invention discloses an acceleration coefficient interval estimation system, which comprises the following steps of: acquiring sufficient complete failure sample data through a Testto-Failure test, designing a'stress layer and degradation characteristic layer 'double-layered Bootstrap sampling rule, and generating a plurality of groups of failure sample combinations; meanwhile, whole-course degradation data of failure samples under double stress are integrated, a cross-stress integrated joint likelihood function is constructed, the acceleration coefficient of each combination is directly solved, and finally the acceleration coefficient interval is determined through statistical analysis. By the adoption of the technical scheme, the problems that existing acceleration coefficient estimation can only achieve point estimation and lacks effective interval estimation adaptive to Testto-Failure data features, an interval result cannot cover failure scene parameter fluctuation, and error accumulation exists in traditional step-by-step solving are solved, and the accuracy of acceleration coefficient estimation and the interval reference value are improved.

The invention belongs to the technical field of composite material durability and reliability evaluation, and discloses a composite material equivalent acceleration and life prediction method and system in a polar region multi-field coupling environment. The natural environment spectrum of the service environment is constructed; key environmental factors are determined based on the environmental spectrum and a damage mechanism, and moisture absorption, freeze thawing, low-temperature freezing and ultraviolet radiation modules are designed and combined to form an accelerated test spectrum; performing a multi-cycle accelerated aging test on the sample according to the spectrum, and synchronously applying a mechanical load; testing the performance after aging by adopting a high-throughput platform to obtain attenuation data; and based on the equivalent relationship between the data and the acceleration spectrum, a life prediction model is established by fitting a residual strength model and calculating an acceleration coefficient, so that life prediction of the composite material in the multi-field coupling environment is realized. The compilation method of the marine environment multi-factor equivalent environment acceleration test spectrum of the composite material is systematically elaborated, and a foundation is laid for research related to life prediction of the composite material in a polar region low-temperature environment.