Mode converters are critical for frequency-tunable terahertz gyrotrons. This study reports the development of a broadband TE(02) mode converter centered at 0.2 THz. An octafeed sidewall coupling structure was employed and the mode purity was analyzed. The converter was built using the technique of x-ray microfabrication. The x rays irradiated on the SU-8 resist and generated a template of very ...

Solid-state transformer (SST); Medium frequency transformer; AC/AC converter; Matrix converter Abstract This paper presents a novel topology of solid-state transformer (SST). In the design process, the AC/DC, DC/AC and AC/AC converters have been integrated to achieve higher efficiency. To obtain higher efficiency from other SST with DC-link topologies, the AC/DC and DC/AC converters have been i...

In this thesis a predefined design parameters are used to present theoretical guidelines for design of low voltage, and low power DC-DC converter with high power efficiency and low levels of EMI (Electro-Magnetic Interference). This converter is used to alter the DC voltage supplied by the power source. Several DC-DC converters of different types and topologies are described and analyzed. Switc...

In this paper, a high-efficiency fuel cell implemented by an LLC resonant dc–dc converter is proposed to save the cost and energy of fuel cell. The proposed converter has zero-voltage switching (ZVS) operation of the primary switches and zero-current switching (ZCS) operation of the rectifier diodes. By frequency modulation control, the output impedance of an LLC resonant converter can be regul...

As the sampling frequency of new ADCs and DACs increases, it gets more difficult to accurately convey the analog stimulus or response to or from the converter under test – there is a bandwidth bottleneck. This paper describes a technique that uses a <100 kHz analog bus, such as the standard 1149.4 bus, to convey an arbitrary analog signal, and converts the signal to or from a high frequency at ...

This paper presents a new single to three phase converter using rotating magnetic field transformer. Conventional transformers have been used in many converters aiming at supplementary improvements and they usually have no critical effect on the conversion technique. In this paper, the conversion technique is based on a special rotating magnetic field transformer in which there are two windings...

The digital pulse width modulator (DPWM) is the crucial building block for digitally-controlled DC-DC switching converter, which converts the digital duty ratio signal into its analog counterpart to control the power MOSFET transistors on or off. With the increase of switching frequency of digitally-controlled DC-DC converter, the DPWM with higher time resolution is required. In this paper, a 1...

A circuit configuration of a single-phase nonisolated online uninterruptible power supply (UPS) with 110-V/220-V input–output voltage ratings is proposed, allowing the bypass operation without a transformer even if the input voltage is different from the output voltage. The converter consists of an ac–dc/dc–dc three-level boost converter combined with a double half-bridge inverter. In this type...

Received Feb 13, 2017 Revised Apr 30, 2017 Accepted May 15, 2017 Switching frequency modulation (SFM) as spread-spectrum technique has been used for electromagnetic interference reduction in switching power converters. In this paper, a switching-frequency-modulated boost power factor correction (PFC) converter operating in continuous conduction mode is analysed in detail in terms of its input p...