This thesis describes the design and construction of a 250 W, 35-60 Vin, 5 Vout dc-dc power converter with a switching frequency of 500 kHz. The converter uses square wave switching and is composed of two power processing stages in series. The first stage, a boost converter, regulates the output voltage of the converter. The second stage, a push-pull converter operating at 100% duty-cycle, prov...

A new CMOS current controlled ring oscillator is investigated. It is based on a 3 stage ring oscillator. Each stage uses a simple NMOS for switching a current source to charge a capacitor and discharging it thereby generating a ramp output. Its oscillation frequency depends on the current source. This simple circuit can have a wide tuning range but has some non-linearity problem. A modification...

A novel topology, Current-Sourcing Push-Pull Parallel-Resonance Inverter (CS-PPRI) was investigated theoretically and experimentally. The proposed power stage is built around a current fed push pull inverter. The main features of the proposed inverter is a load independent output current and Zero Voltage Switching (ZVS). It is suggested that the proposed CS-PPRI is a viable al ternat ive for re...

A new family of single-switch three-phase highpower-factor rectifiers, which have continuous input and output currents, is introduced. By using a multiresonant scheme, the transistor operates with zero-current switching (ZCS), and the diodes operate with zero-voltage switching (ZVS). These multiresonant rectifiers with a single transistor are capable of drawing a higher quality input-current wa...

Current source inverter (CSI) operates to output a specified ac current waveform from dc sources. Talking about power quality, harmonics distortion of is problem an circuit. Generating multilevel will have less content than traditional three-level waveform. In addition non-ideal conditions switches, i.e. voltage drop in diodes, conductors or controlled the performance controller applied circuit...

Cost-effective high-performance IR imaging cameras based on Quantum Well Infrared Photodetectors (QWIP) need CMOS readout structures which allow effective operation at temperatures compatible with inexpensive long-life coolers. At such high temperatures (around 72 K), the QWIP suffers from large background and dark currents (Fig. 1), which have a tendency to saturate the integrating capacitor i...

The purpose of this study is to generate a highly stable DC current by using a superconducting transformer. For the first trial stage, a 100 A class superconducting transformer was designed and fabricated for operation at the temperature of liquid nitrogen. The secondary coil of the transformer was wound with a superconducting Bi-2223 tape, and the turn ratio of the primary and secondary windin...