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Considered the features of modern automatic control systems of pantographs. The spectral density analysis of pantograph contact force at high speeds showed requirements for robust control systems, which allows to significantly improve the quality of the current collection. Proposed the ways to improve the automatic control systems for pantographs, aimed at improving the speed and reducing the inertia of the system.

A mathematical model has been developed for an adaptive automatic brake control system for a freight train using an Extended Kalman Filter (EKF) to identify the actual parameters of the train and its braking system. To evaluate the performance of the proposed automatic control system, a simulation experiment was carried out using a probabilistic formulation of the research problem and the developed automatic brake control model. The purpose of the experiment is to determine the probabilistic characteristics of the random variable representing the deviation of the train’s stopping coordinate from the specified value. The adequacy of the number of simulation runs for obtaining reliable statistical characteristics in this study was determined using a method for estimating the confidence interval bounds for the sample mean and variance for the given number of trials. Histograms were obtained for the distribution of stopping-point deviation during targeted braking with the EKF algorithm switched off and on. To estimate the probability that the stopping-point deviation exceeds the specified limit, a theoretical distribution law for the random variable was selected and verified using the nw2 goodness-of-fit test. It is shown that without the proposed algorithm for identifying braking system and train parameters (the Extended Kalman Filter, EKF), the deviation from the target stopping point during precision braking can lead to serious violations of train-operation safety. The proposed automatic pneumatic brake control system provides high-quality control, improving the accuracy of targeted stopping of a train at a specified track coordinate. The work was carried out at the expense of budget financing within the framework of the state assignment No. 103-00001-25-02 dated 20.03.2025.

Nowadays a frequency-controlled externally excited synchronous motor intensively uses in highly automated high-power electric drives. Earlier there were less reliable and more carefully maintained electromechanical direct current systems in these applications. At the same time, setting up of the closed-loop automatic control systems with subordinate regulation of the synchronous machines is the more difficult task. This is because a synchronous machine is a more complex control object. The purpose of this work is a comparative analysis of transients. In this case, saturation is taken into account according to the magnetic flux in the air gap. The coordinates of the machine are regulated by two different automatic control systems. The first system is typical, which uses field-oriented control of the magnetic field of the stator, the second system is upgraded, it selects the law of control of the magnetic field depending on the static load. Special attention in the current article is paid to the method of accounting for the saturation of the magnetic system of the motor and the construction of a mathematical and simulation model convenient. This article substantiates the feasibility of synthesizing more complex automatic control systems are ones with variable structure. The choice of the magnetic field control law in such systems avoids the negative effect of saturation of the machine's magnetic system on the quality of transients. The models presented in the current work can be used in the design of real controlled synchronous electric drives operating under high loads.