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Showing 1 to 20 of 42 for “"thyristor"”.
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Optically triggered thyristor for capacitor discharge applications
… of the use of light to trigger semiconductor thyristors for capacitor discharge applications has been conducted. The investigation consisted of a technical literature and background search, design and analysis of optically silicon thyristors, and simulations of a capacitor discharge circuit …
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3-Phase gate-turn off thyristor inverter
… designed, constructed and tested. Gate Turn-Off Thyristors (GTO's) are used as the main switching elements in the Inverter stage of the Drive. The drive requirements of GTO's are studied in detail.
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Design and fabrication of Emitter Controlled Thyristor
The Emitter Controlled Thyristor (ECT) is a new MOS-Gated Thyristor (MGT) that combines the ease of a MOS gate control with the superior current carrying capability of a thyristor structure for high-power applications. An ECT is composed of an emitter switch in series with the thyristor, an …
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Design and Fabrication of the Emitter Controlled Thyristor
The Emitter Controlled Thyristor (ECT) is a new MOS-Gated Thyristor (MGT) that combines the ease of a MOS gate control with the superior current carrying capability of a thyristor structure for high-power applications. An ECT is composed of an emitter switch in series with the thyristor, an …
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Development of the Advanced Emitter Turn-Off (ETO) Thyristor
… semiconductor device, the emitter turn-off (ETO) thyristor, which is targeted to improve the limitations of the present high power devices. Major improvements in electrical and mechanical designs of the ETO for high power and high frequency operation are proposed which result in improved …
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Direct digital control of thyristor networks : an investigation into the on-line control of thyristor networks by means of a small digital computer
… of a digital computer to the on-line control of thyristor networks. This will involve producing hardware and software to determine firing sequences, firing delays, etc., and to execute the firing instructions. These are to be determined by the computer from the initial instructions and …
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DC thyristor circuit breakers: An investigation of current interruption ability
The aims of the project were to investigate DC Thyristor Circuit Breaker (TCB) current interruption and appraise the current interruption performance in simulated systems. A generalized analysis was developed which enabled succinct assessment of the current interruption performance of different …
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Innovative GTO Thyristor Based Switches Through Unity Gain Turn-Off
The Gate Turn-Off (GTO) Thyristor has the best voltage blocking and current conducting capabilities among all known high power semiconductor devices. To improve its dynamic performances to meet the increased demand in high-performance high-power applications, a special driving technique, namely …
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Robust decentralized control of power systems through excitation systems and thyristor controlled series capacitors
… of power systems through excitation systems and Thyristor Controlled Series Capacitors (TCSC). Hence the dissertation consists of two parts. In the first part an algorithm for the design of nonlinear decentralized excitation control is developed based on a feedback linearization technique. …
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A study of the turn-on mechanisms in thyristors
Mechanisms of thyristor turn-on wore studied. An attempt was made to relate the ‘on’ plasma spreading velocity to the small signal current gain value of the n-p-n transistor section of the thyristor. The extent to which the thyristor turns on initially largely affects the speed of turning-on the …
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Direct digital control of a synchronous machine
With the advancement of thyristor technology, variable speed alternating current drives are providing improved performance over conventional systems. The aim of this thesis is to investigate the possibilities of direct digital control of a thyristor converter and to determine the major parameters …
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A DC chopper controller for a battery electric vehicle
… conditions. The operation of transistor and thyristor choppers is described, and their suitability for use in a vehicle drive system is discussed. A proposed vehicle control system, incorporating a thyristor array and associated logic for implementing the mode selection, is described and …
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Novel Power Semiconductor Devices and Technologies
… and 1700V fast recovery diodes and two MOS gated thyristor structures viz. the Accumulation Layer enhanced Emitter Switched Thyristor (ALEST) and the Clustered IGBT (CIGBT). Furthermore the insight into the principles of operation and modern optimisation techniques of fast recover diodes, IGBT’s …
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Electrical, Magnetic, Thermal Modeling and Analysis of a 5000A Solid-State Switch Module and Its Application as a DC Circuit Breaker
… semiconductor switch, the emitter turn-off (ETO) thyristor as the main interruption switch. In order to meet the requirement of being a high-current circuit breaker, ETO parallel operation is needed. Therefore the major effort of this dissertation is dedicated to the development of a high-current …
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Application of High-Power Snubberless Semiconductor Switches in High-Frequency PWM Converters
… switches. These switches, including the thyristor and the Gate Turn-Off (GTO) thyristor, had the capacity to handle very high voltages and currents but lacked the ability to perform high frequency switching. Low-power converters, such as computer power supplies and low horsepower motor …
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Modelling and Performance Evaluation of the Virtual Air Gap Variable Reactor
… reactor is most commonly implemented as a thyristor controlled reactor (TCR) by switching in and out a constant reactance to achieve an averaged variable reactance. By using a virtual air gap, a continuously variable reactance is possible. The VAG-VR offers a better dynamic response, …
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Investigation of Control Concepts for High-Speed Induction Machine Drives and Grid Side Pulse-Width Modulation Voltage Source Converters
… end converters commonly operate in parallel to thyristor converter fed dc drives. Behavior of the voltage-oriented controlled active front end converter with L-filter in the presence of a parallel thyristor converter is investigated. The design of the LCL-filter components according to the given …
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Novel MOS-gated bipolar device concepts towards a new generation of power semiconductor devices.
… Transistor (IGBT) and the IVIOS Controlled Thyristor (MCT) have been among the first :tvIOS-gated bipolar devices with high blocking capability and reduced on-state power losses. Presently these devices are fabricated using the conventional DIVIOS technology. Recently, a new technology, …
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Z-source circuit breakers in naval power systems
… a circuit through regenerative turn-on of the thyristor. An electrically-scaled model and a simulation model are used to characterize voltage transients that could lead to this false triggering. The results of this experiment show that these transients are within the specifications of …
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