To develop an efficient variable speed compressor motor system

This research presents a proposed new method of improving the energy efficiency of a Variable Speed Drive (VSD) for induction motors. The principles of VSD are reviewed with emphasis on the efficiency and power losses associated with the operation of the variable speed compressor motor drive, particularly at low speed operation.The efficiency of induction motor when operated at rated speed and load torque is high. However at low load operation, application of the induction motor at rated flux will cause the iron losses to increase excessively, hence its efficiency will reduce dramatically. To improve this efficiency, it is essential to obtain the flux level that minimizes the total motor losses. This technique is known as an efficiency or energy optimization control method. In practice, typical of the compressor load does not require high dynamic response, therefore improvement of the efficiency optimization control that is proposed in this research is based on scalar control model.In this research, development of a new neural network controller for efficiency optimization control is proposed. The controller is designed to generate both voltage and frequency reference signals imultaneously. To achieve a robust controller from variation of motor parameters, a real-time or on-line learning algorithm based on a second order optimization Levenberg-Marquardt is employed. The simulation of the proposed controller for variable speed compressor is presented. The results obtained clearly show that the efficiency at low speed is significant increased. Besides that the speed of the motor can be maintained. Furthermore, the controller is also robust to the motor parameters variation. The simulation results are also verified by experiment

Urban and extra-urban hybrid vehicles: a technological review

Pollution derived from transportation systems is a worldwide, timelier issue than ever. The abatement actions of harmful substances in the air are on the agenda and they are necessary today to safeguard our welfare and that of the planet. Environmental pollution in large cities is approximately 20% due to the transportation system. In addition, private traffic contributes greatly to city pollution. Further, “vehicle operating life” is most often exceeded and vehicle emissions do not comply with European antipollution standards. It becomes mandatory to find a solution that respects the environment and, realize an appropriate transportation service to the customers. New technologies related to hybrid –electric engines are making great strides in reducing emissions, and the funds allocated by public authorities should be addressed. In addition, the use (implementation) of new technologies is also convenient from an economic point of view. In fact, by implementing the use of hybrid vehicles, fuel consumption can be reduced. The different hybrid configurations presented refer to such a series architecture, developed by the researchers and Research and Development groups. Regarding energy flows, different strategy logic or vehicle management units have been illustrated. Various configurations and vehicles were studied by simulating different driving cycles, both European approval and homologation and customer ones (typically municipal and university). The simulations have provided guidance on the optimal proposed configuration and information on the component to be used

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

Study of challenges in technology development and market penetration of hybrid electric vehicles in Canada

Growing concerns of the economic and environmental impact of petroleum combustion by on-road transportation have accelerated the development of alternative fuel vehicles; of these, the hybrid electric vehicle (HEV) is currently the most commercially successful technology. It integrates an electric drivetrain to the internal combustion engine for optimized engine operation giving significantly higher fuel efficiency and lower emissions. However, despite their well recognized benefits, Canadian consumers have shown reluctance in adapting HEVs so far. This thesis discusses the immediate need for Canada to adopt more efficient and eco-friendly transportation systems and analyzes the cost effectiveness and tailpipe emissions of HEVs that offer a suitable alternative. The factors inhibiting market acceptance of hybrids are have been reviewed and a set of comprehensive policy guidelines and measures have been proposed to provide financial incentives, enforce emission regulations and support technology development of hybrid vehicles. As part of the highlighted target, challenges in key areas of HEV technology have been discussed and one such challenge is addressed by proposing a more robust electric motor drive for vehicle traction

The applications of ultrasonic sensor

Ultrasonic sensor usually used for distance measurement and obstacles detection. This sensor is low cost and suitable for range up to few metres for distance measurement applications. However, this sensor has limitations which are wide beam width and sensitivity to the mirror – like surfaces. Despite the disadvantages, there are several applications of these sensors such as wireless obstacle detection, collision control and avoidance, distance measurement and smart parking system. Each of the applications has difference approaches suggested by the researchers. Baharuddin M et al. proposed that in order to give a reliable distance measurement, both infrared and ultrasonic sensors are used together [1]. This paper discussed about four applications of ultrasonic sensors in details which are wireless obstacle detection, collision control and avoidance, distance measurement and smart parking system

Torque Control

This book is the result of inspirations and contributions from many researchers, a collection of 9 works, which are, in majority, focalised around the Direct Torque Control and may be comprised of three sections: different techniques for the control of asynchronous motors and double feed or double star induction machines, oriented approach of recent developments relating to the control of the Permanent Magnet Synchronous Motors, and special controller design and torque control of switched reluctance machine

Field programmable gate array hardware in the loop validation of fuzzy direct torque control for induction machine drive

Introduction. Currently, the direct torque control is very popular in industry and is of great interest to scientists in the variable speed drive of asynchronous machines. This technique provides decoupling between torque control and flux without the need to use pulse width modulation or coordinate transformation. Nevertheless, this command presents two major importunities: the switching frequency is highly variable on the one hand, and on the other hand, the amplitude of the torque and stator flux ripples remain poorly controlled throughout the considered operating speed range. The novelty of this article proposes improvements in performance of direct torque control of asynchronous machines by development of a fuzzy direct torque control algorithm. This latter makes it possible to provide solutions to the major problems of this control technique, namely: torque ripples, flux ripples, and failure to control switching frequency. Purpose. The emergence of this method has given rise to various works whose objective is to show its performance, or to provide solutions to its limitations. Indeed, this work consists in validation of a fuzzy direct torque control architecture implemented on the ML402 development kit (based on the Xilinx Virtex-4 type field programmable gate array circuit), through hardware description language (VHDL) and Xilinx generator system. The obtained results showed the robustness of the control and sensorless in front of load and parameters variation of induction motor control. The research directions of the model were determined for the subsequent implementation of results with simulation samples.Вступ. В даний час пряме управління моментом дуже популярне в промисловості і викликає великий інтерес у вчених у галузі частотно-регульованого приводу асинхронних машин. Цей метод забезпечує розв'язку між керуванням моментом, що крутить, і магнітним потоком без необхідності використання широтно-імпульсної модуляції або перетворення координат. Тим не менш, ця команда представляє дві основні незручності: з одного боку, частота комутації сильно варіюється, а з іншого боку, амплітуда пульсацій моменту і потоку статора залишається погано контрольованою у всьому діапазоні робочих швидкостей. Новизна цієї статті пропонує поліпшення характеристик прямого керування моментом, що крутить, асинхронних машин шляхом розробки нечіткого алгоритму прямого управління моментом, що крутить. Останнє дозволяє вирішити основні проблеми цього методу управління, а саме: пульсації моменту, що крутить, пульсації потоку і нездатність контролювати частоту перемикання. Мета. Поява цього методу породило різні роботи, метою яких є показати його ефективність чи запропонувати рішення стосовно його обмежень. Дійсно, ця робота полягає у перевірці нечіткої архітектури прямого управління моментом, що крутить, реалізованої в наборі для розробки ML402 (на основі схеми Xilinx Virtex-4 з програмованою користувачем вентильною матрицею), за допомогою мови опису обладнання (VHDL) та генераторної системи Xilinx. Отримані результати показали робастність керування та безсенсорного керування при зміні навантаження та параметрів керування асинхронним двигуном. Визначено напрями дослідження моделі для подальшої реалізації результатів на імітаційних вибірках

A New design of fuzzy logic controller optimized By PSO-SCSO applied To SFO-DTC induction motor drive

In this paper, a new strategy for the design of fuzzy logic controllers (FLC) is proposed. This strategy is based on the optimization, by the particle swarm optimization (PSO) Algorithm and by sine-cosine based swarm optimization (SCSO) Algorithm, of the input-output gains and the geometric forms of the triangular membership functions of the proposed FLC. This latter is obtained by the minimizing a cost function based on combining two criterions, the Integral Time Absolute Error (ITAE) and Integral Absolute Error (IAE). A comparison, between the conventional FLC and the proposed FLC is carried out. The PSO-FLC shows a remarkable improvement in the performances of the controlled induction motor