The paper is devoted to the application of the simplex optimization algorithm in the field of magnetic measurements, namely in measuring the demagnetization curve of highly coercive magnetic materials. The algorithm has found its place in the implementation of a new method based on the full-scale model approach and the Gills-Atterton hysteresis model, the essence of which is also described in the work. It is expected that the new method will make it possible to more accurately determine the demagnetization curve of permanent magnets by using voltage meters instead of classical induction sensors, which will avoid the accumulation of error. The simplex optimization algorithm makes it possible to optimize the parameters of the Gills-Atterton model in such a way that the simulated mathematical model of a highly coercive magnetic material best corresponds to the measured magnetic material. The method is tested on a multiphysical model built in the COMSOL Multiphysics software package and includes calculations of an inductor and a permanent high-coercive magnet.
Keywords: permanent magnet, neodymium magnet, highly coercive material, magnetic material, Fourier-Bessel decomposition, approximation, momentum, optimization, simplex, Nelder-Mead algorithm, mathematical model, coercive force, hysteresis
The work is devoted to the development of a new method for determining the demagnetization curve of high-coercive permanent magnets, for example, magnets made of NeFeB alloy. It is expected that the new method will make it possible to more accurately determine the demagnetization curve of permanent magnets by using voltage and current meters instead of class induction sensors, which will avoid the accumulation of error that occurs when integrating a signal from induction sensors. The paper describes in detail the algorithm of the new method for determining the demagnetization curve, provides references to the methods and algorithms used in the development of the new method. The method was tested on a multiphysical model of a permanent magnet and a magnetizing installation built in the COMSOL Multiphysics software package.
Keywords: permanent magnet, neodymium magnet, highly coercive material, magnetic material, Fourier-Bessel decomposition, approximation, momentum, optimization, simplex, Nelder-Mead algorithm, mathematical model, coercive force, hysteresis
The construction of a regression model of errors in the approximation of the current curve from factors affecting this error is described. The following factors are selected as influencing factors: the number of coefficients of the Bessel-Fourier decomposition and the number of points on which the original function is constructed. Experimental data were obtained as a result of modeling electrical processes occurring in a pulsed magnetization reversal system.
Keywords: permanent magnet, regression model, Bessel-Fourier decomposition, approximation, momentum, factors, function, curve, momentum, error
The system for measuring cargo dimensions is designed for streaming measurement of cargo dimensions, which can be luggage at airports and transshipment bases, various parcels, as well as commercial cargo. The authors of the article developed a structural and functional diagram of a control and measuring system for dynamic measurement of cargo dimensions, and also considered the principles of its operation.
Keywords: control and measuring system, measurements, cargo dimensions, luggage, automated systems
A method for measuring the magnetic characteristics of high-coercive permanent magnets made of rare-earth materials, such as neodymium-iron-boron and samarium-cobalt, is proposed. The essence of the method is as follows: the data on the measured supply voltage and the characteristics of the magnetizing installation base a mathematical model; the measured shape of the magnetizing current pulse is fed into the mathematical model and compared with the simulated current pulse in the comparison device; further, if the difference in current characteristics does not satisfy the measurement accuracy, then adjustments are made to the mathematical model. Thus, the mathematical model determines the magnetic characteristics of a permanent high-coercive magnet. The method is developed based on full-scale model tests using a multiphysical computer model. The implementation of the measurement method is based on modern IT solutions, the multiphysical model is built in the COMSOL Multiphysics software package.
Keywords: magnet, magnetic parameter, multiphysical model, magnetization, highly coercive material, neodymium, wavelet, Fourier analysis, COMSOL
Actuator drives are widely used both in consumer electronics and in industrial systems: as all kinds of locks, couplings; as part of valves that control the flow of liquids or gases; in robotics; alarm systems, etc. In the event of a failure of the actuator drive, it is not typical for it to restore the operating mode. As a consequence, predicting reliability plays an important role. The article discusses the development of a method for processing the weber-ampere characteristics of actuator drives. Weber-ampere characteristics are converted into ampere-weber ones, reflected by the maximum flux linkage value, and interpolated by the current values that are the same for all characteristics. The characteristics obtained in this way are transformed by the method of principal components and are represented by a point in three-dimensional space. By the location of the points of the center of mass and the dispersion of the groups of characteristics of one electromagnetic drive, a forecast is made about its state by the time of the next check according to the regulations. This method was applied to the characteristics of 10 actuator drives, each of which was subjected to mechanical resistance during operation. The characteristics transferred into the space of the principal components forms a figure resembling a boomerang. The movement of points from the upper edge of the "boomerang" through the center to the lower edge reflects the deterioration of its working properties.
Keywords: prediction, reliability, actuator drive, weber-ampere characteristic, principal components, flux linkage, data processing, duty cycle, malfunction, Statistica, points cloud, performance data
In modern times due to the growth of mass production of electronic devices, it becomes necessary to quickly and accurately verify their characteristics. At the same time, device testing, as a rule, includes a set of different types of checks performed at different stages of the production process. In particular, the analog signature analysis method is used for these purposes. It allows you to quickly detect faults at the component level, which makes it useful in various stages of production, such as incoming inspection, testing printed circuit boards or repairing faulty devices. This article discusses the basic principles of the method, as well as the features of its application.
Keywords: analog signature analysis, component level testing, current-voltage characteristic, fault localization