Motor-driven System Research Articles

An Integrated Optimal Design for Guaranteed Cost Control of Motor Driving System With Uncertainty

In this article, a plant/controller integrated design strategy based on the nested optimization strategy and guaranteed cost control for a motor driving system is developed. Because of the coupling between the plant design and the controller design, the conventional sequential design methods cannot guarantee an overall optimality for the controlled motor driving system. The integrated design strategy proposed in this article aims to tackle this problem by simultaneously optimizing the controller design and plant design. The integrated design objective is to drive the largest load and guarantee the satisfactory robust control performance for reference tracking subject to parametric uncertainties. This is enabled by integrating a guaranteed cost controller into the integrated design strategy and improves the reliability of the control scheme. A novel combined performance index including the plant design objective and the control performance is developed as the integrated design cost function for the motor driving system. A nested optimization strategy is employed so that the optimality of the system can be calculated in an efficient and reliable way. Experimental results demonstrate the effectiveness of the proposed integrated design method.

A Simulink / MATLAB Model of a Three-Phase Sinusoidal PWM Inverter Driven Induction Motor

A three-phase voltage source inverter driven induction motor dynamic model developed using Simulink / MATLAB is presented. The presented model is derived from the d-q motor model. A modular approach is used in the construction of the motor-drive system model. The model presented is useful for studying both the steady-state and transient behavior of the motor drive system. The developed model enables the user to access all parameters of interest. Modifications can be made to the system model in order for it to be used with other motor drive system topologies. The model has benefits for use by undergraduate student researchers, and professors when used as a teaching tool in undergraduate courses.

Energy Conservation and Efficiency by Energy Efficient Motor in India

Electricity demand in India is increasing at a rapid pace because of growth in Economy, urbanization, infrastructure development and the living standard of people. According to the United Nation’s world population prospects (2017), India’s population is 1.34 billion which will go grow further and surpass China by 2025[1]. According to the IMF, the Indian economy is expected to grow by 7.5% in FY19-20 and 7.7% in FY20-21[2]. Increased population and growth in GDP are associated with increased energy demand. India’s primary energy consumption was 754 Mtoe in 2017 and expected to reach 1928 Mtoe in 2040[3]. Major energy demand is from the Industrial sector which was 51% of total primary energy consumption in 2017 and expected to reach 990 Mtoe, by 2040 [3]. Rising energy demand and dependence on coal-based energy generation capacity, leading to the emission of Green House Gases (GHG). Most of India’s Greenhouse gas emissions are from energy sector having 68.7% contribution in overall greenhouse gas emission. Agriculture, Industrial process land-use change and forestry (LUCF), and waste, contributed 6.0%, 3.8% and 1.9% respectively in overall GHG emission in 2014. [4]. Reducing the GHG emission in India is a major challenge in front of the Government as the Government has to maintain sustainable growth with the contribution in mitigating the effect of climate change. Govt. has pledged to Paris Agreement for the reduction in emission intensity of GDP by 33-35% by 2030 below 2005 level [5]. In the reduction of GHG emission, energy efficiency’s contribution is estimated at approx. 51% [6]. The industrial sector can contribute most in reducing GHG emission and contributes to nationally determined contribution. Industry consumes 40%-45% of total energy consumption and motor-driven system consumes 70% [7] of total Industrial energy. Most of the energy in Industries are consumed to run the motor for various purposes and consumes a major chunk of energy which can be reduced to a significant level by replacing the standard motor with energy efficient motor. 90% of the motor in Indian industries are IE1 or below IE1 standard [8] and required replacement. By installing the energy efficient motor, the industry can save huge energy, cost and reduce CO2 emission. Observing the opportunity for energy saving by energy efficient motor, this paper aims to analyze how energy efficient motor is capable of reducing energy consumption, and how it can contribute to energy conservation. Methodology adopted in this paper is secondary research, that answers to questions like; why Industry need energy efficient motor, how energy efficient motor can save energy and increases efficiency, cost-benefit analysis of installing energy efficient motor, barriers to the installation of energy efficient motor and solution to those barriers in migration from the standard motor to energy efficient motor in India.

Sliding mode‐based velocity and torque controllers for permanent magnet synchronous motor drives system

To minimise the torque ripple for vector control of interior permanent magnet synchronous motor (IPMSM) of railway traction system, this study proposes a new velocity, torque and current three-loop control system, and designs a velocity and torque sliding mode controller (SMC) for permanent magnet synchronous motor (PMSM) driven system. First, the mathematical model of IPMSM is described and the new velocity and torque closed-loop control system for PMSM is designed. Second, the velocity SMC and torque SMC are designed. The fast convergence of the motor velocity and torque is realised, and the torque ripple is reduced effectively. The stability of the designed SMC is analysed. Finally, the effectiveness of the proposed scheme was compared with PI by simulations and experiments. The results show that the proposed method has good control performance and strong robustness.

Design concepts of low-frequency electromagnetic devices based on a data-driven approach

PurposeThis paper aims to propose a data-driven approach to determine the design guidelines for low-frequency electromagnetic devices.Design/methodology/approachTwo different devices, a core-type single-phase transformer and a motor-drive system, are used to show the usefulness and generalizability of the proposed approach. Using a finite element solver, a large database of design possibilities is created by varying design parameters, i.e. the geometrical and control parameters of the systems. Design rules are then extracted by performing a statistical analysis and exploring optimal and sub-optimal designs considering various targets such as efficiency, torque ripple and power factor.FindingsIt is demonstrated that the correlation of the design parameters influences the way the data-driven approach must be made. Also, guidelines for defining new design constraints, which can lead to a more efficient optimization routine, are introduced for both case studies.Originality/valueUsing the proposed approach, new design guidelines, which are generally not obtainable by the classical design methods, are introduced. Also, the proposed approach can potentially deal with different parameter–objective correlations, as well as different number of connected systems. This approach is applicable regardless of the device type.

Power Analysis of a 3-kW Class Motor-Driven Multipurpose Walking-Type Transplanter

The purpose of this study is to measure and analyze the power of the motor-driven transplanter to provide useful information for the optimal design of an electric drive system. An electric transplanter was developed by replacing its engine-driven system with an electric motor-driven system. The data acquisition system was constructed to measure torque and rotational speed data during field operations. The field experiment was performed under three operational conditions at planting distance levels (26, 42, and 63 cm) as follows: (1) driving without transplanting operation, (2) transplanting operation without driving, and (3) transplanting operation with driving. In the case of the driving without transplanting operation, the average power requirement of the driving part increased from 0.14 to 0.124 kW. In the case of the transplanting operation without driving, the maximum power requirement of the transplanting part dramatically decreased from 1.084 to 0.346 kW. As the planting distance increased, the average power requirement decreased by 45.7-53.2%. In the case of the transplanting operation with driving and compared to the rated power (3 kW) according to the planting distance, the average total power requirement of the electric transplanter is 1.345 kW at 26 cm (44.8% to rated power), which was approximately 1.57-2.2 times larger than the power requirement at 42 and 63 cm. It can be seen that the continuous operation time is 8.9, 12.8, and 14.3 h at each planting distance. The results of this study can provide useful information for designing an optimal electric drive system of a motor-driven transplanter considering the load characteristic according to planting distance.

The Model Technology of Stepping Motor Driving System

This paper proposes the dynamic characteristics of load motion have great influence on the performance of stepping motor. The dynamic model of stepping motor driving system is established on basis of least-squares, the system identification experiment is carried out on an actual Numerical Control Plate Printer drive system, and the dynamic parameters of the system were identified with MATLAB. The results have a good practical value to the optimal control of stepping motor.

System identification and a model-based control strategy of motor driven system with high order flexible manipulator

Purpose This paper aims to propose a novel system identification and resonance suppression strategy for motor-driven system with high-order flexible manipulator. Design/methodology/approach In this paper, first, a unified mathematical model is proposed to describe both the flexible joints and the flexible link system. Then to suppress the resonance brought by the system flexibility, a model based high-order notch filter controller is proposed. To get the true value of the parameters of the high-order flexible manipulator system, a fuzzy-Kalman filter-based two-step system identification algorithm is proposed. Findings Compared to the traditional system identification algorithm, the proposed two-step system identification algorithm can accurately identify the unknown parameters of the high order flexible manipulator system with high dynamic response. The performance of the two-step system identification algorithm and the model-based high-order notch filter is verified via simulation and experimental results. Originality/value The proposed system identification method can identify the system parameters with both high accuracy and high dynamic response. With the proposed system identification and model-based controller, the positioning accuracy of the flexible manipulator can be greatly improved.

Variable damping injection control of PMSM drive systems based on isolated shoot‐through Z‐source inverter

This study proposes a novel permanent magnet synchronous motor (PMSM) driven system based on isolated shoot-through Z-source inverter (IST-ZSI). The IST-ZSI is utilised to replace the traditional Z-source inverter. Compared with the conventional Z-source inverter-based PMSM drive system, the new drive system can not only solve the coupling of the boost factor and modulation but also provide a large regulation range of the output voltage. For the PMSM drive system, a variable damping injection controller is proposed via the passivity-based control and maximum torque per ampere control principle. Then, the load torque observer is designed to improve the stability of the PMSM system with uncertain load torque. The simulation and experimental results show that the variable damping injection control has satisfactory dynamic and static control performance.

Investigation of electromechanical coupling torsional vibration and stability in a high-speed permanent magnet synchronous motor driven system

A permanent magnet synchronous motor (PMSM) driven system is a typical electromechanically coupled system. In this paper, to improve the operational performance and stability of the PMSM system, torsional vibrations due to the electromechanical coupling effects are studied. An electromagnetic excitation model was first established to consider the effect of torsional angle on magnetomotive force. Then, nonlinear torsional vibration equations of the driven system were obtained. In addition, an electromechanically-coupled torsional vibration mechanism based on natural frequency modulation of the system was revealed. Finally, the torsional vibration equations and coupled mechanism were validated against experimental results describing the actual torsional vibration and a numerical method was used to verify our theoretical analysis. The results provide a theoretical basis for the parameter design of electromechanical transmission systems.

Study of the induction motor electric drive efficiency in transients during their acceleration

The electric drive with a squirrel-caged induction motor working in frequent start-stop modes is the object of this study. These drives have wide applications nowadays, such as in electric vehicles and hybrid electric vehicles, so improvement of their efficiency during the transients is an important task today. The one of the problems of such drives lays in the high energy consumption during the transients, especially if we talk about the acceleration of the motor. Due to the high starting currents large amount of consumed energy is dispersed as heat on the motor windings. The experimental studies carried out in this work have proved the necessity of limitations of these currents. However, such a decision will lead to the increase of the motor acceleration period which means that the starting currents, even having lesser magnitude, will last longer. This consequence will, therefore, also cause higher energy losses. So, there should be a point of the optimum – the acceleration period, during which the electric drive consumes the least possible energy. In order to determine the optimal acceleration period, the computer model of the electric drive with a squirrel-caged induction motor, controlled by a smooth start device, was developed in this paper. The smooth start device provides the possibility of evenly increasing of the voltage from zero to the rated value. The research has proven the existence of the optimal voltage increasing period, during which the motor acceleration heat losses are minimal. This optimal point depends only on the motor-drive system parameters and remains consistent for any applied load. The research results provide the possibility of improving the efficiency of the electric drives working in frequent start-stop modes due to a slight increasing of the motor acceleration period that leads to the reduction of the starting currents.

The Role of Temperature-Dependent Material Properties in Optimizing the Design of Permanent Magnet Motors

The effects of temperature-dependent material properties, including those of silicon steel and permanent magnet (PM) materials, on the design process of inverter-fed PM motors are investigated in this paper. The magnetization curves of these materials are measured experimentally at different temperatures and are imported into a finite-element package. Then, a statistical study of an integrated motor-drive system consisting of an interior PM motor connected to a space vector modulated inverter is performed by assigning four different temperatures and building a design space of various objectives including the integrated system efficiency, speed limits, motor startup quality, torque ripple, total harmonic distortion, and power factor as the geometrical dimensions are varied. The results reveal that incorporating the realistic material properties into the design process is essential. Moreover, different motor-drive performances have totally different variation rates as the material properties are changed. Finally, a set of optimal designs at different temperatures is proposed to show the effect of changing material properties.

A Computer-Aided Design Process for Optimizing the Size of Inverter-Fed Permanent Magnet Motors

A process for designing an inverter-fed motor while taking into account the performance of the inverter is proposed. To draw a comparison, the classical approach to machine sizing is discussed and its shortcomings in achieving a more optimal solution to the motor-drive system design problem are pointed out. The results prove that designing the motor as an independent system may give less optimal solutions compared to the case where an integrated system is considered. Therefore, the machines and the inverters should be designed simultaneously. An inverter-fed interior permanent magnet motor is investigated, and the corresponding design guidelines are presented. These guidelines are based on the knowledge extracted from an inclusively modeled, sampled, and simulated design space. The reliability of the design, the inverter efficiency, and the priorities of the transient, rated and flux weakening operations are assigned as the selection criteria. Moreover, various user-package interfaces are proposed to show how the designer should be guided towards a more realistic design choice. Finally, four different design cases are presented and compared to the output of the classical machine sizing process. The proposed approach serves as a proposal for the next generation of processes implemented with the aid of a high-performance cloud-computing service.

Design and Advanced Robust Chassis Dynamics Control for X-by-Wire Unmanned Ground Vehicle

X-by-wire Unmanned Ground Vehicles (UGVs) have been attracting increased attention for various civilian or military applications. The x-by-wire techniques (drive-by-wire, steer-by-wire, and brake-by-wire techniques) provide the possibility of achieving novel vehicle design and advanced dynamics control, which can significantly improve the overall performance, maneuverability, and mobility of the UGVs. However, there are few full x-by-wire UGVs prototype models reported in the world. Therefore, there is no book that can fully describe the design, configuration, and dynamics control approach of full x-by-wire UGVs, which makes it difficult for readers to study this hot and interesting topic. In this book, we use a full x-by-wire UGV, developed by our group, as the example. This UGV is completely x-by-wire with four in-wheel motors driven and a four-wheel independent steer steer. In this book, the overall design of the UGV, the design of the key subsystems (battery pack system, in-wheel motor-driven system, independent steer system, remote and autonomous control system), and the dynamics control approach will be introduced in detail, and the experiment's results will be provided to validate the proposed dynamics control approach.

Research status of structure optimisation design for in-wheel motor driven system

As one of the key technologies of the next generation pure electric vehicles, the in-wheel motor driven electric vehicle has been paid plenty of attention by the auto industry, because of its obvious technical advantages in the overall arrangement of the vehicle, the chassis active control and the control convenience. The in-wheel motor (IWM) driven system integrates the motor, the speed reducer, the brake and so on into the narrow space and its integrated structure and performance directly affect the driving/braking performance of the driving wheels and the vehicle performance. Therefore, as one of the core technologies, the optimisation design of the integrated structure has always been a difficult and hot spot in the research institutes. In this paper, the development status of the optimisation design technology for the integrated structure of the in-wheel motor driven system is analysed and summarised, and the future research directions are discussed.

Performance test and analysis of key components of pure electric vehicles

Tests are performed in this article to analyse the lithium iron phosphate (LiFePO4) battery performance and drive motor system performance, so as to give a sufficient understanding of performance characteristics of key components of pure electric vehicles (EV). The EV powertrain system performance test bed is applied for the tests. Applying a LiFePO4 battery (192 V/100 A·h) as the research object, a calculation method is developed for battery charging/discharging efficiency. Tests are performed to analyse the influence of battery temperature on terminal voltage, as well as the influence of battery SOC and charging/discharging current on the battery efficiency. Applying an AC asynchronous motor (rated power 32 kW) as the research object, tests are performed to analyse the influence of battery voltage on the performance of motor system, the efficiency characteristics of drive motor within the high-speed field weakening area, and the efficiency characteristics of drive motor in normal working conditions. Through the tests and analysis for the performance of EV battery and motor, it can provide guidance for the matching of EV powertrain system, and gives basis for development of high-efficient EV control strategies.

Operation of Variable-Frequency Drive Motor Systems With Source Voltage Unbalance

This paper describes efficiency measurement in induction motor and variable-frequency drives systems under imposed voltage unbalance at the drive input. A number of drives from different manufacturers are tested with matching sizes of motors and the results are compared. The results highlight differences in the effect of voltage unbalance on drive performance. The results also indicate that intrinsic motor performance has important influence on motor-drive system efficiency.

A Statistical Solution to Efficiently Optimize the Design of an Inverter-Fed Permanent-Magnet Motor

This paper provides the fundamentals of integrated motor-drive system design knowledge that could be used as a basis to change the existing machine design approach from being a separate machine design tool to a more advanced engineering package in which the inverter performance can also be considered. Various users' preferences including motor performances in the transient, rated, and flux-weakening operations along with the inverter quality are studied by means of a detailed cosimulation process which utilizes finite element method, MATLAB, and SIMULINK packages to build the framework based on which magnetic, electric, and electronic devices and quantities are modeled, simulated, and postprocessed. A case study of an interior-permanent-magnet motor connected to a field-oriented controlled drive is investigated and the design process concepts are developed by means of a comprehensive statistical analysis. It is shown that incorporating the inverter quality into the design process changes the idea of optimum motor design, and hence, not only the design parameters but also the expectations from motor performances have to be revised. In fact, an integrated motor-drive system design process regarding the best motor operations in the transient, rated, and flux-weakening modes is targeted with the purpose of addressing design challenges of interior-permanent-magnet motors. To this end, the start-up torque, the rise time, the motor efficiency, the torque ripple, the constant power speed range, the characteristic current, the inverter efficiency, and the system cost, which cover a group of important objectives of different applications, are investigated. Finally, a design package will be able to address different designers’ expectations more efficiently using the approach proposed herein.

A novel control system simulation modeling method considering the real hardware platform and the software structure

Abstract During the realization of a control algorithm for the practical motor driver system, simulation is an important procedure before the algorithm is implanted into the DSP chip. In most circumstances, the simulation is done before the algorithm is realized, which is simulated under the condition of continuous control system. However, the simulation neglects the effect of the discrete system caused by the software structure, which the algorithm in DSP is triggered by the events trigger interrupt. Moreover, the model is complicated and cannot reflect the real hardware and the pipelined algorithm. Furthermore, the accuracy and running time of the simulation model are controlled by the simulation step setting. In this paper, a novel discrete simulation model is realized and introduced to consider the effect of both hardware and software and to reduce the running time with a considerable accuracy. The unification of the parameters is also considered in the model to make the system more efficient. The result reveals that the proposed method reflects the effect of both the real hardware and the software, which form a close loop between the simulation and algorithm realization. The simulation runtime is reduced, while the accuracy is unchanged, and it is suitable for the simulation of high-speed motor driver system.

Phase fault attenuation in SRM based on generalized predictive control and filter design

The development of fault tolerant control can improve the safety and performance of a driven motor system. In the case of switched reluctance machine, the remaining phases can be used to maintain the machine operation inside certain limits due its independent coils. However, situations where this kind of machine needs to be restarted must be avoided, since the rotation direction and even the start itself cannot be guaranteed. In this sense, a control strategy that achieves a fast attenuation of the effect caused by a phase fault is welcomed. This work proposes the use of generalized predictive control in a RST structure allied to a filter designed to attenuate the disturbance due to phase faults. An disturbance model was identified in different operation points, when the system is submitted to a one- and two-phase faults. That disturbance model is used to design a filter able to compensate the phase faults. Experimental results are presented which demonstrate the effectiveness of the proposed strategy.