Increase the Efficiency of an Induction Motor Feed from Inverter for Low Frequencies by Combining Design and Control Improvements

Speed-controlled induction motors have the most significant potential for energy savings. The greatest problems with obtaining high efficiency occur in motors with a wide range of rotational speed regulation, as in the motors for driving industrial washing machines under consideration. While for the highest speeds, the dominant phenomenon is at field weakening. The problem is obtaining the optimal size of the magnetic flux for low rotation speed to prevent excessive saturation increasing current, and reduction of efficiency. This problem is usually solved by selecting the appropriate control for an already built machine. The authors propose a combination of activities when designing the motor structure with the selection of proper control, which allows for high efficiency. Since the drive does not require precise speed control or obtaining the required dynamics, it was possible to use an inexpensive control in an open loop, avoiding the cost of transmitters. Furthermore, the number of design parameters that are subject to change is significantly limited by technological factors and the available space in the washing machine. Proper parameter selection was made using a peripheral method assisted by field-circuit simulations. The proposed approach can be used in designing structures and selecting motors controls for other applications.

Power Consumption Model of Permanent-Magnet Direct-Drive Belt Conveyor System Based on GACO–BP

Permanent-magnet direct-drive belt conveyors (PMDDBCs) rotate at high speed most of the time, resulting in a large number of invalid energy consumption. To realize the speed regulation of PMDDBC, it is necessary to clarify the relationship between the belt speed, coal quantity of the conveyor and total power of the system. Based on the BP neural network, this paper establishes the power consumption model of PMDDBC, which is related to coal quantity, belt speed and total power. Furthermore, an improved hybrid algorithm (GACO) that combines the advantages of genetic algorithm (GA) and ant colony optimization (ACO) is proposed to optimize the BP power consumption model. The GACO–BP power consumption model is obtained. The original power consumption model is compared with the GACO–BP power consumption model through experiments. Results demonstrate that the GACO–BP power consumption model reduces various prediction errors, while the optimization ability, prediction accuracy and convergence speed are significantly enhanced. It provides a reliable speed regulation basis for the permanent-magnet direct-drive belt conveyor system and also provides a theoretical reference for energy savings and consumption reduction in the coal industry.

POWER EQUIOMENT CONTROL SYSTEM OF A SHUNTING LOCOMOTIVE WITH AUTOMATIC SPEED CONTROL ALGORITHM

Work objective is to develop an algorithm for automatic speed regulation and to ensure its integration into the system of adaptive combined control of the power equipment of the locomotive TEM7A. Research methods: methods of the theory of automatic control, modern programming methods, trial trips. Research results and novelty. For the first time, the problem of automatic maintenance of "creeping" train speeds with high accuracy has been solved in the practice of domestic locomotive construction. It is established that the developed algorithm for automatic control of the humping speed and splitting up of shunting locomotive TEM7A allows maintaining a given speed in the range of operating speeds up to 8 km / h. Conclusion. The developed algorithm is integrated into the microprocessor control system of the power equipment of TEM7A shunting locomotive and does not require additional costs when through the locomotive operation. Maintaining a uniform speed of movement can also be used in the mode of manual control of the locomotive by the driver, while the value of the stipulated rate is set by the driver using the display module of the control panel.

Model predictive direct suspension force control of a bearingless induction motor based on sliding mode observer

PurposeThe purpose of the control method proposed in this paper is to address the problem of the poor anti-interference of the suspension winding current in the traditional bearingless induction motor (BL-IM) direct suspension force control process.Design/methodology/approachA model predictive direct suspension force control of a BL-IM based on sliding mode observer is proposed in this paper. The model predictive control (MPC) is introduced to the traditional direct suspension force control to improve the anti-interference of the suspension current. A sliding mode flux linkage observer is designed and applied to the MPC system, which reduces the error of the parameter observation and improves the robustness of the system. The strategy is designed and implemented in the MATLAB/Simulink and the two-level AC speed regulation platform.FindingsThe simulation and experimental results show that the performance of the BL-IM under the control method proposed in this paper is better than that under the traditional direct suspension force control, and the suspension performance of the motor and the anti-interference of the control system are improved.Originality/valueThis study helps to improve the suspension performance of the motor and the anti-interference of the control system.

Intelligent Speed Regulation Control in Switched Reluctance Motor of Electric Vehicle Based on Neural Network Parameter Identification

This paper studies the intelligent speed regulation control of switched reluctance motor of electric vehicle based on neural network parameter identification. Starting with the analysis of the performance of switched reluctance motor, the nonlinear flux linkage characteristic inversion model and torque characteristic model of switched reluctance motor are established based on BP neural network. This paper studies and improves the fast self configuration algorithm of BP neural network. Finally, the nonlinear simulation model of switched reluctance motor is established under Matlab/Simulink. The model can be used for further control research. In this paper, the integrated control method of instantaneous torque control based on torque observation and three-step commutation control is studied, and the simulation analysis is carried out. The results show that this method can effectively reduce the torque ripple of switched reluctance motor and improve the performance of its drive system.

Intelligent Speed Regulation Control of Switched Reluctance Motor of Electric Vehicle Based on Neural Network Parameter Identification

Based on the analysis of the related theories of switched reluctance motor, this paper designs and implements the intelligent speed regulation system of switched reluctance motor for electric vehicle. The speed regulation system has the characteristics of high efficiency and energy saving, wide speed regulation range and small starting current. The system also has the advantages of large starting torque, frequent start and stop, forward and reverse switching, high torque / inertia ratio and four quadrant operation. The system can provide a good solution for variable speed drive. The digital controller of the system is composed of TMS320F2812 DSP and EPM7128S CPLD, which can realize the starting, electric and braking functions of electric vehicles. Experiments show that the switched reluctance motor drive system for electric vehicle has good control performance and strong fault tolerance. The system can meet the requirements of various working conditions of electric vehicles and has broad development prospects.

A novel squirrel cage eddy current coupling with adjustable radial air gap and its performance analysis

A novel squirrel cage eddy current coupling with adjustable radial air gap was presented, which can change the output speed by changing the air gap thickness in radial direction between the copper strips and the permanent magnet. It has the advantages of no axial force in speed regulation and less eccentric force in axisymmetric structure. The 2-D electromagnetic torque model of the rotor was established, and the influence of the air gap thickness on the electromagnetic torque was also studied by finite element method. Further, a novel method to solve the dynamic equation of the eddy current coupling was proposed based on the effect of air gap thickness and relative speed on torque characteristics, and was applied to the speed regulation performance analysis. In addition, the influence of the relative magnetic permeability of the permanent magnet back yoke and the internal rotor on the speed regulation performance was studied.