Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 36 for “"hard switching"”.
-
A Soft-Switched Grid-Connected DC/AC Inverter with Low Current Ripple
… are based on simple full-bridge circuits with hard switching. However, hard-switching imposes several difficulties on the performance of DC/AC inverters. Thus, increasing the efficiency and decreasing the switching losses of these inverters have been an active research area. In particular, …
-
Pulse Density Modulated Soft Switching Cycloconverter
… stage cycloconverters generally incorporate hard switching at turn on and soft switching at turn off. This hard switching at turn on combined with the slow switching speeds of thyristors (the switch of choice for standard cycloconverters) limits their use to lower frequency applications. This …
-
Prediction of the power losses of PWM inverter drives for permanent magnet synchronous motors
… is developed for predicting power losses for a hard-switching threephase IGBT inverter drive for synchronous motor applications. For a given set of motor parameters, semiconductor device parameters and motor operating conditions, the various losses and the temperature rises of semiconductor …
-
Multilevel capacitor-clamped DC-DC boost converter structure with soft-switching technique implementation for high power density achievement
… DC-DC boost converter (CCBC) with soft-switching implementation for high power density achievement. The proposed 4-level CCBC has an ability to reduce the size and volume of passive components and have similar characteristics with the conventional DC-DC converter. Principally, the …
-
Implementation of a Novel Soft-Switching Topology for Switched Reluctance Motor Drives
… design, develop, implement and test a novel soft-switching inverter topology suitable for switched reluctance motor drives. Present research being done in the field of switched reluctance motor drive inverters, including soft-switching inverters, is discussed. The novel topology is presented and …
-
Experimental investigation of semiconductor losses in cryogenic DC-DC converters
… at temperatures down to 20 K. In particular hard switching, synchronous rectifier, zero-voltageswitching and multi-level circuit prototypes are examined, focusing on the losses in the semiconductor devices. The prototypes operated from 120 V and 500 V DC supplies at power levels up to 500 W …
-
Analysis and Evaluation of Soft-switching Inverter Techniques in Electric Vehicle Applications
… and the critical assessment of the AC side soft-switching inverters in electric vehicle (EV) applications. Although numerous soft-switching inverter techniques were claimed to improve the inverter performance, compared with the conventional hard-switching inverter, there is the lack of …
-
Fully Soft-Switching Modulation Methods for SRC-Unfolding Inverter
… converters, which suffer from hard switching, the need for auxiliary components, and/or high current stresses. Meanwhile, the series resonant converter has been prevalent in past decades due to its simplicity and high efficiency. Therefore, it is intriguing to design a …
-
Hard Switched Robustness of Wide Bandgap Power Semiconductor Devices
… promise enhanced capabilities (e.g., higher switching speed, smaller die size, lower junction capacitances, and higher thermal conductance) over legacy Si devices, thus making the traditional qualification experiments ineffective. This work begins by introducing a new methodology for …
-
A zero voltage switching boost converter using a soft switching auxiliary circuit with reduced conduction losses
… to reverse recovery of the boost diode and high switching losses caused by hard switching of the boost switch. Many variations of the original boost topology have been suggested to overcome these problems. The Zero Voltage Transition Boost converter is one such solution. In such a converter an …
-
Zero voltage switching flyback and forward converter topologies
… performance improvements. Improved zero voltage switching (ZVS) flyback and forward dc/dc converter topologies are developed in this thesis. They employ an auxiliary circuit, with only a few small components and switching devices, to achieve ZVS of the main switch. Steady state analyses are …
-
High Power Inverter EMI Characterization and Improvement by Auxiliary Resonant Snubber Inverter
… of EMI have been commonly identified as high switching dv/dt and di/dt rates interacting with inverter parasitic components. The reduction of parasitic components relies on highly integrated circuit layout and packaging. This is the way to deal with noise path. On the other hand, switching …
-
Design of a 405/430 kHz, 100 kW Transformer with Medium Voltage Insulation Sheets
… for their ability to operate at higher switching frequencies. High frequency (HF) operation enables soft switching which, when achieved, reduces switching losses via either zero voltage switching (ZVS) or zero current switching (ZCS) depending on the converter topology. In addition to …
-
Stacked-Switched Electrolytic Capacitor-less AC/DC Power Converters
… electrolytic capacitors, diode bridges, and hard-switching circuits, leading to reduced reliability, increased losses, and limited power density. Additionally, the need for bidirectional energy flow—such as Vehicle-to-Grid (V2G) and Vehicle-to-Home (V2H)—requires grid-compliant converters …
-
Reconfigurable and Interference-Tolerant Receivers for Next Generation Wireless Systems
… the sub-7 GHz spectrum, offers significant hardware efficiency for 5G systems. However, addressing strong interferers in this wide and congested spectrum remains a major design challenge. N-path filters offer a promising solution for efficiently suppressing interference, thanks to their …
-
Soft-Switching, Interleaved Inverter for High Density Applications
… the latest transistor technology to push switching frequency to shrink passive filter size. Furthermore, while high efficiency is an important thermal handling strategy, it must be weighed against increases in component size. Google's Little Box Challenge shone light on these challenges in …
-
Describing Cognitive Change in Normal Aging and Early-stage Dementia
… semantically or phonemically related words) and switching (shifting between clusters; Abwender et al., 2001; Lanting et al., 2009; Troyer et al., 1997). The objective of the current research was to investigate measures of clustering and switching on verbal fluency tasks for healthy individuals …
-
Efficiency improvement in nanometre CMOS outphasing power amplifiers
… the supply voltage is shorted to ground during switching. The short-circuit can be prevented by driving the two transistors with dead-time-separated voltages to stop them from switching simultaneously. To investigate this technique, a hard-switching CMOS PA with a novel driver that generates two …
-
Control, Analysis, and Design of SiC-Based High-Frequency Soft-Switching Three-Phase Inverter/Rectifier
… conduction mode (CRM) high-frequency soft-switching three-phase ac-dc converters (inverter and rectifier). The soft-switching technique with SiC devices grounded in CRM makes the operation of the ac-dc converter at hundreds of kHz possible while maintaining high efficiency with high power …
-
Design of dual-input two phase dc/dc converter with modified pulse width modulation (mpwm)
… by proposing the enhanced Modified PWM (MPWM) switching scheme, it is able to solve the issues of the overlapping unregulated input sources. Furthermore, with the proposed multiphase configuration, the input current stresses in the switching devices are reduced and it has the benefit of a …
Page 1 of 2