Electrotechnical complex of maglev rolling stock

Background: The development of work in the field of creating cargo maglev transport systems is associated with the development and study of the electro technical complex of the rolling stock for the operating range with long stretches in poorly developed territories. Aim: The aim of the work is to substantiate the structure and parameters of the components of the electro technical complex of the rolling stock, to study the operating modes. Methods: The main research methods are functional structural analysis and synthesis, computer modeling, computational studies, analysis of research results. Results: As a result of the research, the factors that determine the appearance of the electrotechnical complex of the rolling stock have been identified. The basic requirements for the electrical complex are formulated. The structure was developed and the parameters of the components of the electrical complex for the transport platform with magnetic levitation were determined. A high-speed flat car model 13-6990 for the transportation of containers was chosen as the closest railway analogue. A computer model of a combined traction-levitation system based on a linear reluctance inductor motor has been developed. The results of computational studies, confirming the physical feasibility of the electrical complex of the rolling stock with linear reluctance inductor motors, are presented. Conclusion: The practical significance lies in the fact that the proposed concept of constructing an electro technical complex of rolling stock provides for the creation of a maglev transport system with a low-cost infrastructure.

Various types of traction synchronous motors for urban use

Asynchronous and valve-inductor (synchronous-reactive) motors have high efficiency at high rotor speeds, while permanent magnet synchronous motors (SPM and IPM) have high efficiency at low and medium frequencies. The latter are the most optimal for urban conditions, and the former for conditions of operation on highways and highways. Synchronous motors with permanent magnets are more expensive, so a good alternative to them can be synchronous-jet motors with permanent magnets, which determine the optimal balance of active and reactive torque, as well as efficiency. Keywords: synchronous motor, asynchronous motor, valve-inductor motor, synchronous-jet motor, permanent magnet, efficiency, operating conditions, reactive torque

Mathematical modelling of transients in the electric drive of the turnout of the mono-sleeper type with switched-inductor motor

Introduction. The study is devoted to the development of the functionality of a railway track switch by introducing a switched-inductor electric drive. This solution justifies simplifying the mechanical part of the switches by changing the gearbox to a ball-screw and locating the all kinematic line of the switches on the mono-sleeper type. Goal. A study of the mono-sleeper turnout type behaviour to meet modern traffic safety requirements and improve operational reliability factors. Methodology. Based on electric drive theory, a kinematic line of a mono-switch turnout type with nonlinear friction characteristic is presented. Using differential equation theory and Laplace transformation, a mathematic description of a four-phase switched-inductor motor with ball-screw in a mechanical line of a single-mass electromechanical system has been made. A simulation mathematical model of the electric drive of mono-sleeper turnout type as the control system with a switched-inductor motor and nonlinear friction characteristic was built in MATLAB. Results. Simulation modelling of a mathematical model of a mono-sleeper turnout type with a switched-inductor motor and ball-screw gear has been developed and implemented. Studies of dynamics of turnout point movement have shown that, in contrast to the motors used today, the switched-inductor motor makes it possible to simplify the mechanical part of the drive, which leads to reduced time spent on laying and maintenance of turnout points, and therefore makes the design more reliable. The application of PID controller and fuzzy speed controller has shown improved dynamics of turnout point, while the fuzzy PID controller provides better performance of the set values and turnout point movements. Originality. First developed a mathematical model of the electric drive of the mono-sleeper turnout type, taking into account nonlinear friction characteristic, as an object of speed control of turnout point movement, is developed. Practical value. The developed mathematical model of a railway track turnout of the mono-sleeper type with a switched-inductor motor and ball-screw gear enables more efficient use of a microprocessor control system, creation of promising electric motor protection means and control of a turnout point.

Magnetoresistive Sensors and Piezoresistive Accelerometers for Vibration Measurements: A Comparative Study

This experimental study focuses on the comparison between two different sensors for vibration signals: a magnetoresistive sensor and an accelerometer as a calibrated reference. The vibrations are collected from a variable speed inductor motor setup, coupled to a ball bearing load with adjustable misalignments. To evaluate the performance of the magnetoresistive sensor against the accelerometer, several vibration measurements are performed in three different axes: axial, horizontal and vertical. Vibration velocity measurements from both sensors were collected and analyzed based on spectral decomposition of the signals. The high cross-correlation coefficient between spectrum vibration signatures in all experimental measurements shows good agreement between the proposed magnetoresistive sensor and the reference accelerometer performances. The results demonstrate the potential of this type of innovative and non-contact approach to vibration data collection and a prospective use of magnetoresistive sensors for predictive maintenance models for inductive motors in Industry 4.0 applications.

THEORETICAL RESEARCH OF THE SWITCHED RELUCTANCE MOTOR VIBROACOUSTIC ACTIVITY

The article describes the features of the occurrence of vibroacoustic activity of a promising type of electric motors – switched reluctance. Explanations of the mechanism of occurrence of an increased level of vibrations and noise from the action of unbalanced radial forces of interaction between the stator and the rotor are given. The calculation of radial forces for a valve-inductor motor is given, on the basis of which recommendations are given to reduce the impact of vibrations and noise from a running motor on a human.

Highly dynamic observer of the magnetic state on the basis of the ventiled inductor motor

The article is devoted to the problem of developing highly dynamic flux observers for three-phase inductor motors. The synthesis of the flux observer is based on the analysis of the instantaneous powers of the motor stator by the vector control of drives. The observation algorithm lacks integral, differential and iterative methods of mathematics. The proposed observer algorithm is implemented in a vector-matrix form for its simplest integration into the modern vector control of electric drives. The observer provides stability and high precision in drives with direct torque control, in which the variation in the angle of the spatial voltage vector of the inverter is much higher than in drives with pulse width modulation. The proposed observer algorithm can be used in cost optimized drives, because its implementation does not require “exclusive” resources of microprocessor control units. The paper presents a time invariant observer algorithm that provides high precision of the observed flux at low inductances and low voltages of the inductor motor. The measured and observed moments of the reluctance motor during the acceleration of the drive were analyzed.

Dynamic and Adjustable New Pattern Four-Vector SVPWM Algorithm for Application in a Five-Phase Induction Motor

In order to improve the Direct Current (DC) bus utilization ratio and realize harmonic suppression of a five-phase induction motor, the SVPWM (Space Vector Pulse Width Modulation) algorithm was researched in depth. Based on an analysis of the present SVPWM algorithm and the volt-second balance principle, a dynamic and adjustable new pattern four-vector SVPWM algorithm was proposed. The algorithm uses the modulation index and zero vector to improve the characteristics of the inductor motor, the function relationship with real-time dynamic ratio between the action–time ratio of the space voltage vector and the modulation index was proposed to maximize DC bus utilization ratio, and the random zero-vector dynamic modulation mode was used to reduce harmonic influence, being able to spread harmonics concentrated around certain frequencies across a wider frequency band and thus produce a more continuous and uniform power spectrum. The new algorithm model was built using Matlab/Simulink, and the simulation and experimental results demonstrated that the algorithm is effective and feasible.