...Prof. R. N. Ganguly along with my fellow batchmates who provided valuable support and co-operation during the execution of project. Introduction The basic function of a transmission system is to transfer electrical power from one place to another or from one network to another network. A transmission system includes the terminal substations, transmission lines and intermediate substations. Transmission systems are required for ● Transfer of bulk power from large group of generating stations upto the main transmission network ● System interconnection ● Transfer of power from main transmission from the main transmission network to secondary substations The increasing need of transmitting greater and greater amounts of power over long distances has led to a continuous increase in transmission voltages. As a rule, larger the amount of power to be transmitted, higher is the requirement of transmission voltages. In India, the transmission voltages in use are 33, 66, 110, 132, 220 & 400 kV . The next higher voltage of 765/800kV has been selected for transmission of huge blocks of power from generating stations to load centres. Necessity of EHV Transmission Reduction of Electric Losses , increase in Transmission efficiency , inprovement of Voltage Regulation and reduction in Conductor Material requirement For transmission of given amount of power over a given distance through...
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...16 Upon curing they shrink more as compared to amorphous thermoplastics. Examples are polypropylene (PP), polyethylene (PE) [1]. S. Amin and M. Amin In order to resolve the problem of low thermal and chemical stability of thermoplastic elastomers, dynamic vulcanization techniques were used in late ] plastic. In dynamic vulcanization the thermoplastic and elastomers are both cross-linked and physically mixed together. This gave rise to a second generation of thermoplastic elastomers which had better tensile strength and oil resistance as compared to those formed by physical mixing only [8]. ] ] ] _ were introduced which were made by same dynamic vulcanization process but using natural and butyl rubbers in place of EPR and EPDM. Natural and butyl rubbers have the advantages like low cost, very good over molding properties, reusable and very easily recyclable scrap [9,10]. Butyl rubber based thermoplastic elastomers have excellent adhesion with other thermoplastics hence it is still used to date for many over molding applications [11]. A list of common thermoplastic elastomers used in modern world is given in Table 1. 1.2.2. Amorphous thermoplastics They are usually transparent and have diffused melting point. The molecules are arranged randomly and ] ] _ to crystalline polymers. Upon curing they shrink less as compared to crystalline thermoplastics [3,4]. Examples are polycarbonate (PC), polymethylmethacrylate (PMMA), polystyrene (PS), polyphenylene oxide (PPO), acrylonitrile...
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...MINISTRY OF POWER AND MINERAL RESOURCES OF THE REPUBLIC OF KAZAKHSTAN APPROVED by Prikaz No 189 of the Minister of Power and Mineral Resources of the Republic of Kazakhstan, as of August 26, 2004.) REGULATIONS ON ELECTRICAL INSTALLATIONS OF THE REPUBLIC OF KAZAKHSTAN (PUE) Astana, 2003 TABLE OF CONTENTS SECTION 1: GENERAL REGULATIONS 10 CHAPTER 1.1: GENERAL 10 SCOPE, TERMS AND DEFINITIONS 10 GENERAL REGULATIONS FOR INSTALLATION OF ELECTRICAL EQUIPMENT 11 CONNECTION OF ELECTRICAL INSTALLATIONS TO THE POWER STATIONS 13 COMMISSIONING OF ELECTRICAL INSTALLATIONS 14 CHAPTER 1.2 POWER SUPPLY AND POWER SYSTEMS 14 SCOPE, DEFINITIONS 14 GENERAL REQUIREMENTS 14 CATEGORIES OF POWER CONSUMING DEVICES AND RELIABILITY OF POWER SUPPLY 15 VOLTAGE LEVELS AND CONTROLS, REACTIVE POWER COMPENSATION 16 CHAPTER 1.3 SELECTION OF CONDUCTORS: HEATING, CURRENT DENSITY AND CORONA DISCHARGE CONDITIONS 16 SCOPE 16 SELECTION OF CROSS-SECTION OF CONDUCTORS: HEATING 17 MAXUIMUM CONTINUOUS CURRENTS FOR WIRES, CORDS AND CABLES IN RUBBER OR PLASTIC INSULATION 18 MAXIMUM CONTINUOUS CURRENTS FOR CABLES IN IMPREGNATED PAPER INSULATION 22 MAXIMUM CONTINUOUS CURRENTS FOR BARE WIRES...
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