PWM-controlled Three Level Stacked Structure LLC Resonant Converter And Method Of Controlling Same

The invention discloses a novel control scheme/strategy for the stacked structure LLC resonant converter. The control scheme includes a control signal as a gating signal of the fourth switch, and gating signals of the first, second and third switches that are operably generated according to the gating signal of the fourth switch. The gating signals of the second switch has a same duty ratio as and a phase shift of 180 degrees from the gating signal of the fourth switch. The gate signals of the first and third switches are complementary with the gate signals of the second and fourth switches, respectively. By adopting the control strategy, a three level LLC resonant network input voltage is generated, which includes Vin, Vin/2 and 0

PWM-controlled Three Level Stacked Structure LLC Resonant Converter And Method Of Controlling Same

The invention discloses a novel control scheme/strategy for the stacked structure LLC resonant converter. The control scheme includes a control signal as a gating signal of the fourth switch, and gating signals of the first, second and third switches that are operably generated according to the gating signal of the fourth switch. The gating signals of the second switch has a same duty ratio as and a phase shift of 180 degrees from the gating signal of the fourth switch. The gate signals of the first and third switches are complementary with the gate signals of the second and fourth switches, respectively. By adopting the control strategy, a three level LLC resonant network input voltage is generated, which includes Vin, Vin/2 and 0

Comparative Analysis of Patch Lesions in the Chick Inner Ear Following Acoustic Trauma: Optical Versus Scanning Electron Microscopy

Neonatal chicks were exposed to an octave band noise with a center frequency of 1.5 kHz at 116 dB SPL for 4 hours. Seven days following overstimulation, the birds were sacrificed. Their basilar papillae were re-moved, fixed in 4% paraformaldehyde, and processed in two steps. First, the ears were immunostained with a supernatant of mouse anti-tectorial membrane antibodies, followed by a diaminobenzidine process. Examinations of the papillae under an optical stereo microscope revealed a patch site with a partially regenerated tectorial membrane (referred to as the honeycomb). After the optical studies, the same ears were post-fixed in 1% osmium tetroxide, dehydrated in ethanol, and processed for scanning electron microscopy (SEM). SEM examinations demonstrated a honeycomb-covered patch lesion in the papilla. Patch lesion perimeters were traced from both the optical and SEM images, and patch areas were calculated. Also, papilla height was measured at the midpoint of the inner ear in both groups. These calculations showed that the patch area and papilla height had shrunk by approximately 37% and 33% , respectively, following the SEM methodology. The decrease in these dimensions may be attributed to several steps required for the SEM specimen preparation, such as critical point drying

Method for modeling and parameter extraction of LDMOS devices

A method for modeling the performance of a laterally diffused metal oxide semiconductor (LDMOS) device across a wide temperature range is disclosed. The method comprises the steps of positioning the device in an environment chamber operable to create a plurality of environment temperatures; connecting the pins of the device to a measurement system operable to measure at least one device characteristic; operating the environment chamber to set a series of four environment temperatures, acquiring a value of the device characteristic from the measurement system at each temperature, and extracting a temperature parameter set based on the value of the device characteristic at each temperature, then generating a temperature-scaling model for the device

Novel High Frequency Silicon Carbide Static Induction Transistor-Based Test-Bed for the Acquisition of SiC Power Device Reverse Recovery Characteristics

A test system is presented that utilizes a high-frequency Silicon Carbide (SiC) Static Induction Transistor (SIT) in place of the traditional MOSFET to test reverse recovery characteristics for the new class of SiC power diodes. An easily implementable drive circuit is presented that can drive the high-frequency SIT. The SiC SIT is also compared to a commonly used Si MOSFET in the test circuit application

Role of Laboratory Education in Power Engineering: Is the Virtual Laboratory Feasible? Part I

IEEE PES sponsors a panel session in the summer power meeting in Seattle on laboratory education in power engineering. Six short papers and one full paper summarize the opinions of the panelist. This paper contains the summary of four of the presentations. The objective of the panel is to discuss the role of laboratory education in power engineering at both the graduate and undergraduate level. The question is what type of laboratory course is needed? Power electronics, electric machines, system simulation, etc? the second objective is to assess the status and value of computer based virtual laboratories. This includes the presentation of experience with virtual laboratories and a list of available tools. The teaching of power system operation can be improved using a simulation laboratory. The available simulation tools and the assessment of their values will be an important topic of the panel. The last presentation gives opposing views, arguing for the traditional laboratory us

Electron transport in quantum dot chains: Dimensionality effects and hopping conductance

Detailed experimental and theoretical studies of lateral electron transport in a system of quantum dot chains demonstrate the complicated character of the conductance within the chain structure due to the interaction of conduction channels with different dimensionalities. The one-dimensional character of states in the wetting layer results in an anisotropic mobility, while the presence of the zero-dimensional states of the quantum dots leads to enhanced hopping conductance, which affects the low-temperature mobility and demonstrates an anisotropy in the conductance. These phenomena were probed by considering a one-dimensional model of hopping along with band filling effects. Differences between the model and the experimental results indicate that this system does not obey the simple one-dimensional Mott\u27s law of hopping and deserves further experimental and theoretical considerations

A Review of Current Research Trends in Power-Electronic Innovations in Cyber-Physical Systems.

In this paper, a broad overview of the current research trends in power-electronic innovations in cyber-physical systems (CPSs) is presented. The recent advances in semiconductor device technologies, control architectures, and communication methodologies have enabled researchers to develop integrated smart CPSs that can cater to the emerging requirements of smart grids, renewable energy, electric vehicles, trains, ships, internet of things (IoTs), etc. The topics presented in this paper include novel power-distribution architectures, protection techniques considering large renewable integration in smart grids, wireless charging in electric vehicles, simultaneous power and information transmission, multi-hop network-based coordination, power technologies for renewable energy and smart transformer, CPS reliability, transactive smart railway grid, and real-time simulation of shipboard power systems. It is anticipated that the research trends presented in this paper will provide a timely and useful overview to the power-electronics researchers with broad applications in CPSs.post-print2.019 K