Traditionally linear actuator applications are addressed by the use of hydraulic systems. The high maintenance cost and poor reliability will always be the most critical problem in the real applications. Benefited from both the high mechanical advantage of the roll screw and the simple structure of the switched reluctance motor,...
This thesis presents algorithms and tools for the automated design of RF LC CMOS voltage controlled oscillators (VCOs) with low phase noise given a set of specifications. The electromagnetic solver, ASITIC, combined with the circuit simulator, SpectreRF, allows optimization of the VCO circuit parameters and inductor layout. This approach gives...
Amorphous oxide semiconductor (AOS) thin-film transistors (TFTs) constitute the central theme of this thesis. Within this theme, three primary areas of focus are pursued.
The first focus is the realization of a transparent three-stage ring oscillator with buffered output and an output frequency in the megahertz range. This leads to...
A new comprehensive wide-band compact modeling methodology for single-ended spiral inductors and differential spiral inductors is presented. The new modeling methodology creates an equivalent circuit model consisting of frequency-independent circuit elements for use in circuit simulators. A fast automated extraction procedure is developed for determining the circuit element values from...
Low noise oscillators are universally needed in digital systems for clock generation and synchronization, and in radio-frequency communication front-ends for frequency up- and down-conversion. Noise in oscillators results in timing jitter, and limits the clock frequency of digital systems. In radio-frequency communication systems, phase noise in oscillators lowers the signal-to-noise...
This thesis presents the development of a supervisory controller for a pre-commercial
Brushless Doubly-Fed Machine (BDFM) drive system. In addition,
characterizations of new diecast rotors for the BDFM are presented. Using the
characterization results from the new rotors, a control scheme was developed to allow a
BDFM to be packaged...
Electricity is the name given to an invisible agent known to us only by its attendant phenomena and by various manifestations called electrical. These manifestations, at first obscure and even mysterious, are now well understood. Indeed its great importance to mankind can only be realized when we remember that it...
Industry today is pushing personal portable handheld communication de- vices, from cellular telephones to personal navigation systems, and society is embracing the push. The goal is to make compact multi-functional handheld products that can transfer information to those around us through high bandwidth mobile communications. These modules rely heavily on...
In an effort to fill an existing need two small electric service
vehicles were designed, constructed, and tested. The first
acted as a feasibility study and the second as a design prototype.
The vehicles had low cost and the capability of being fabricated by
their users as two main design...