Scalar Variable Speed Motor Control for Traction Systems with Torque and Field Orientation Filter (original) (raw)
Related papers
A MODIFIED SCALAR CONTROL OF AN INDUCTION MOTOR WITH APPLICATIONS IN TRACTION
iaeme
In this work we consider an induction motor used in haulage of heavy passenger trains. We show that a very simple and rugged control apparatus, based on the Volts/Hz algorithm, is sufficient to ensure excellent acceleration characteristics with very low transients except at startup. We propose a closed loop control scheme featuring a two level voltage source inverter, using pulse width modulation at full flux and six step operation in the flux weakening regime. We recommend a few additions to the regular scalar control strategy viz. (a) that the excitation frequency be updated once every revolution or so, (b) that the principal harmonic voltage vector experience no discontinuities in phase during acceleration and (c) that the centres of the hexagonal trajectories of the stator flux in the flux weakening regime be as close as possible to the origin of the d-q plane. The success of the strategy is predicated on the slow acceleration which traction motors usually exhibit.
Control Strategies for Induction Motors in Railway Traction Applications
Energies, 2020
This paper analyzes control strategies for induction motors in railway applications. The paper will focus on drives operating with a low switching to fundamental frequency ratio and in the overmodulation region or six-step operation, as these are the most challenging cases. Modulation methods, efficient modes of operation of the drive and the implications for its dynamic performance, and machine design will also be discussed. Extensive simulation results, as well as experimental results, obtained from a railway traction drive, are provided.
2002
This paper looks at design of a controller for an induction motor electrical drive useful for high speed railway applications. The design of the controller is based on the cascade control mode using the standard model of the motor referred to d-q axes fixed with the rotor flux vector. It is assumed that the speed and the rotor flux are the variables to be controlled and their dynamics must be decoupled, which is accomplished by means of a nonlinear compensator, which gives decoupling of the direct and in-quadrature currents. According to the aforementioned cascade control mode, the bandwidth of the current inner control loops must be selected higher than that of the speed and rotor flux outer control loops. To take into consideration the remarkable uncertainties in the knowledge of the inertia coefficient, adaptive control techniques are used to design the speed control loop. To cope with uncertainties in electromagnetic parameters, robust control techniques are used for designing t...
A Novel Approach for Controlling the Electric Drives Used in Electric Trains
Acta Polytechnica Hungarica, 2014
Nowadays, the DC motors have been replaced by induction motors in most of the industrial applications. Substantially, Induction motors are single speed, but they can produce high power density in a wide range of speed by applying new drive controllers based on constant V/f, DTC and vector control theory. Electric motors control is mainly accomplished by power electronic drives based on control schemes like constant v/f. However, the challenge of torque generation with fast time response and high accuracy was met by using the controllers based on vector control and DTC. In applications like electric train, generation of torque with rapid time response is so vital. As an example, in Anti skid-Anti slid system, the generated torque should vary between zero and the desirable value quickly to prevent the electric train from slip and the wheels from skidding on the rail. However, the accuracy of the torque magnitude due to its high value is not an important issue and most of the time, errors up to 3 percents in the generated torque is acceptable. In this paper, the control systems used in constant v/f drives are modified in order to generate torque with fast time response and acceptable accuracy. Control systems stability is an essential concern in electric drives and is arisen from the complexities in the controller's process and the time delays. In the proposed system, by simplification of the drive controllers, the instability problem of the control units is eliminated which in turn reduces the calculation time delays and results in torque generation with appropriate time response. Furthermore, the overall cost of the drive system is reduced considerably.
Energies, 2022
This paper deals with the analysis of the operating conditions of traction drives of the electric locomotives with asynchronous traction motors. The process of change of the catenary system voltage was found to have a stochastic character. The method of current controller synthesis based on the Wiener–Hopf equation was proposed to enable efficient performance of the traction drive control system under the condition of the stochastic nature of the catenary system voltage and the presence of interferences, when measuring the stator current values of the tractor motor. Performance simulation of the proposed current controller and the current controller used in the existing vector control systems of the traction drives used in the electric locomotives was implemented. The results of the performance simulation of the proposed current controller were compared with the performance of the current controller in existing vector control systems of the traction drives. The results are applicabl...
Analysis of Control Methods for the Traction Drive of an Alternating Current Electric Locomotive
Symmetry, 2022
The analysis of operating conditions of traction drives of electric locomotives with asynchronous traction motors has been carried out. It was found that during operation in the output converter of an asynchronous motor, defects may occur, which leads to asymmetric modes of its operation. Models of a traction drive of an electric locomotive with asynchronous motors with scalar and vector control of the output converter are proposed, taking into account asymmetric operating modes. As a result of the simulation, the starting characteristics of the traction drive were obtained for various control methods both in normal and emergency modes of the drive. For the drive-in emergency mode, the following cases were investigated: the balance of the converter output voltages and the turn-to-turn circuit of 10% of phase A winding of the motor stator; imbalance of the output voltages of the inverter and an intact motor; imbalance of the output voltages of the converter and interturn short circui...
Configurations and control of traction motors for electric vehicles: A review
Chinese Journal of Electrical Engineering, 2017
In recent decades, worldwide global warming and reduction in petroleum resources have accelerated researcher's attention to produce alternative sustainable and environmentally clean transportation systems. Electrification of vehicular technology is capable of curbing the environmental pollution problem in an efficient and effective way, due to high efficiency electric motors, development and advancement in the field of power electronic devices, digital signal processing and advanced control techniques. This article presents a comprehensive review on different configurations/ architecture of electric vehicles(EVs) and hybrid electric vehicles(HEVs), traction motors for electric propulsion system and high performance speed sensorless control of traction drive. The basic architecture key components of hybrid vehicle and different power train configurations with respect to applications and limitations are discussed. The integral part of electric propulsion system, traction motor classes for desired operational characteristics and limitations are summarized from a system perspective with the latest improvements. High performance traction motor control techniques are discussed with respect to automotive applications. Finally, speed sensorless control techniques research trends as well as an extensive review on rotor speed estimation techniques for robust and efficient sensorless traction drive control are highlighted. This article provides state of the art key global trends and tradeoff of various technologies with future trends and potential areas of research.
2012
The present paper presents the calculation of the speed controller parameters of the scalar control systems with permanent magnet synchronous motors with sinusoidal current control used in low power applications. The shaft position sensor used to determine the rotor position, respectively its rotation speed is made of two Hall sensors. In the considered numeric example, we presented the Bode diagrams of the speed loop with and without considering the viscous friction coefficient, in the case the low-pass filter does or does not interfere in the negative reaction. Permanent magnet synchronous motors (PMSM) are used in the regulated systems with variable speed, by their association with frequency converters. Generally, in the case of PMSM, in order to determine the rotor position, a shaft position sensor is used, while to determine the rotor speed, a speed sensor is used, or it can be calculated using the position data, thus the speed sensor can be removed. The frequency converter use...