Study of the generator/motor operation of induction machines in a high frequency link space power system

Static power conversion systems have traditionally utilized dc current or voltage source links for converting power from one ac or dc form to another since it readily achieves the temporary energy storage required to decouple the input from the output. Such links, however, result in bulky dc capacitors and/or inductors and lead to relatively high losses in the converters due to stresses on the semiconductor switches. The feasibility of utilizing a high frequency sinusoidal voltage link to accomplish the energy storage and decoupling function is examined. In particular, a type of resonant six pulse bridge interface converter is proposed which utilizes zero voltage switching principles to minimize switching losses and uses an easy to implement technique for pulse density modulation to control the amplitude, frequency, and the waveshape of the synthesized low frequency voltage or current. Adaptation of the proposed topology for power conversion to single-phase ac and dc voltage or current outputs is shown to be straight forward. The feasibility of the proposed power circuit and control technique for both active and passive loads are verified by means of simulation and experiment

Control strategies for Brushless DC motors

Tato diplomová práce se zabývá strategiemi řízení, které jsou dostupné pro bezkartáčové DC motory, a které mohou být použity pro řízení rychlosti pohonů elektrických vozidel. Úkolem práce je studium rozličných řídicích algoritmů, nalezení způsobů, jak optimalizovat jejich výkon, a zároveň simulovat jejich chování pro ověření jejich vlastností. Závěrečná etapa práce spočívá v přípravě implementovatelného řídicího algoritmu, který je poté spuštěn na laboratorním stanovišti s aktivním řídicím systémem založeným na zpětné vazbě PID regulátoru a uživatelského rozhraní (HMI) pro snadnou interakci v průběhu testu.Master's Thesis researching the various control strategies available for BLDC motor control that can then be employed in the speed control of electric vehicle drive systems. The task involved studying the various control algorithms, finding ways to optimize their performance and simulate them as a proof of concept. The final stage of the thesis involved the preparation of an implementable control algorithm that was then run on a test bench with an active PID feedback-based control system and HMI for easy interaction in runtime

A New Battery/Ultracapacitor Energy Storage System Design and its Motor Drive Integration for Hybrid Electric Vehicles

This paper proposes a new energy storage system (ESS) design, including both batteries and ultracapacitors (UCs) in hybrid electric vehicle (HEV) and electric vehicle applications. The conventional designs require a dc-dc converter to interface the UC unit. Herein, the UC can be directly switched across the motor drive dc link during the peak power demands. The resulting wide voltage variation due to UC power transfer is addressed by the simple modulator that is introduced in this paper, so that the motor drive performance is not disrupted. Based on this new methodology, this paper further introduces two ESS schemes with different topologies, namely 1) UC rating and 2) energy flow control. They are applicable to both lightly and heavily hybridized HEVs. Both schemes have the benefits of high efficiency (without a dc-dc link) and low cost. The simulation and experimental results validate the new methodology

THREE-STAGE SYNCHRONOUS OVERMODULATION CONTROL OF FIVE-PHASE INVERTERS

Novel three-stage algorithm of synchronous PWM control of five-phase inverter in the zone of overmodulation has been proposed and investigated. It provides smooth transition from linear modulation range to the ten-step operation mode of five-phase system at the maximum fundamental frequency, with full DC-bus voltage utilization. Simulations give the behavior of five-phase system during synchronous PWM control in the zone of overmodulation

Serangga dan mitos suku kaum jakun, Kampung Peta, Mersing Johor

This study focuses on seeing insects from the mythical perspective of the Orang Asli tribe of Jakun, Kampung Peta, Mersing Johor. The existence of insects in the life of every ethnic in Malaysia has brought various elements of myths. Therefore, when combining myths and insects, it could be said that myth is a human way of understanding, expressing and linking insects to him/herself as well as a group/culture. The practice of using insects among ethnic groups in daily life is called etnoentomology. In this study, the insects studied are the butterfly (Lepidoptera), the odonates (Odonata) and the cicadas (Homoptera). This is because these insects are very popular in the community and have their own myths that are brought into the local culture of belief

Control strategy for a modified cascade multilevel inverter with dual DC source for enhanced drivetrain operation

This paper presents a new control strategy for a modified cascade multilevel inverter used in drivetrain operations. The proposed inverter is a three-phase bridge with its dc link fed by a dc source (battery), and each phase series-connected respectively to an H-bridge fed with a floating dc source (ultracapacitor). To exploit the potentials of the inverter for enhanced drivetrain performance, a sophisticated yet efficient modulation method is proposed to optimise energy transfer between the dc sources and with the load (induction motor) during typical operations, and to minimise switching losses and harmonics distortion. Detailed analysis of the proposed control method is presented, which is supported by experimental verifications

Design and Control of Electrical Motor Drives

Dear Colleagues, I am very happy to have this Special Issue of the journal Energies on the topic of Design and Control of Electrical Motor Drives published. Electrical motor drives are widely used in the industry, automation, transportation, and home appliances. Indeed, rolling mills, machine tools, high-speed trains, subway systems, elevators, electric vehicles, air conditioners, all depend on electrical motor drives.However, the production of effective and practical motors and drives requires flexibility in the regulation of current, torque, flux, acceleration, position, and speed. Without proper modeling, drive, and control, these motor drive systems cannot function effectively.To address these issues, we need to focus on the design, modeling, drive, and control of different types of motors, such as induction motors, permanent magnet synchronous motors, brushless DC motors, DC motors, synchronous reluctance motors, switched reluctance motors, flux-switching motors, linear motors, and step motors.Therefore, relevant research topics in this field of study include modeling electrical motor drives, both in transient and in steady-state, and designing control methods based on novel control strategies (e.g., PI controllers, fuzzy logic controllers, neural network controllers, predictive controllers, adaptive controllers, nonlinear controllers, etc.), with particular attention to transient responses, load disturbances, fault tolerance, and multi-motor drive techniques. This Special Issue include original contributions regarding recent developments and ideas in motor design, motor drive, and motor control. The topics include motor design, field-oriented control, torque control, reliability improvement, advanced controllers for motor drive systems, DSP-based sensorless motor drive systems, high-performance motor drive systems, high-efficiency motor drive systems, and practical applications of motor drive systems. I want to sincerely thank authors, reviewers, and staff members for their time and efforts. Prof. Dr. Tian-Hua Liu Guest Edito

Induction Motors

AC motors play a major role in modern industrial applications. Squirrel-cage induction motors (SCIMs) are probably the most frequently used when compared to other AC motors because of their low cost, ruggedness, and low maintenance. The material presented in this book is organized into four sections, covering the applications and structural properties of induction motors (IMs), fault detection and diagnostics, control strategies, and the more recently developed topology based on the multiphase (more than three phases) induction motors. This material should be of specific interest to engineers and researchers who are engaged in the modeling, design, and implementation of control algorithms applied to induction motors and, more generally, to readers broadly interested in nonlinear control, health condition monitoring, and fault diagnosis

Design and Measurement of Integrated Converters for Belt-driven Starter-generator in 48 V Micro/mild Hybrid Vehicles

With reference to a 48 V belt-driven starter-generator, used in micro/mild hybrid vehicles, the paper shows the design and measurement of an integrated H-bridge and of a compact DC/DC converter, both fabricated in low-cost HV-MOS technology. The H-bridge is in charge of rotor excitation and, thanks to a direct copper bonding of the HV-MOS devices on a ceramic substrate, it ensures a full-integrated solution with low ON-resistance values. The compact DC/DC converter interfaces the 48 V power domain with the lower voltage domain of sensing and control electronics, such as 5 V and 1.65 V in this case study, without using cumbersome inductors and transformers. The latter are difficult to integrate in silicon technology. The converter has a multi stage architecture, where each stage implements a switched capacitor regulation. Multiple voltage outputs are supported, with a configurable regulation factor, sustaining an input voltage variation from 6 V (in case of cranking) up to 60 V. Specific design techniques have been implemented to reduce electromagnetic interference (EMI), typical of switching converters. Experimental measurements on fabricated prototype chipsets confirm the suitability of the presented designs for low-EMI 48 V application