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Tsai, Fu-Sheng

Publications and source records attributed to Tsai, Fu-Sheng.

High-frequency ac power distribution in Space Station

A utility-type 20-kHz ac power distribution system for the Space Station, employing resonant power-conversion techniques, is presented. The system converts raw dc voltage from photovoltaic cells or three-phase LF ac voltage from a solar dynamic generator into a regulated 20-kHz ac voltage for distribution among various loads. The results of EASY5 computer simulations of the local and global performance show that the system has fast response and good transient behavior. The ac bus voltage is effectively regulated using the phase-control scheme, which is demonstrated with both line and load variations. The feasibility of paralleling the driver-module outputs is illustrated with the driver modules synchronized and sharing a common feedback loop. An HF sinusoidal ac voltage is generated in the three-phase ac input case, when the driver modules are phased 120 deg away from one another and their outputs are connected in series.

Tsai, Fu-Sheng↗

A complete dc characterization of a constant-frequency, clamped-mode, series-resonant converter

The dc behavior of a clamped-mode series-resonant converter is characterized systematically. Given a circuit operating condition, the converter's mode of operation is determined and various circuit parameters are calculated, such as average inductor current (load current), rms inductor current, peak capacitor voltage, rms switch currents, average diode currents, switch turn-on currents, and switch turn-off currents. Regions of operation are defined, and various circuit characteristics are derived to facilitate the converter design.

Tsai, Fu-Sheng↗

Computer modeling and simulation of a 20kHz ac distribution system for Space Station

A computer model of a 20 kHz, ac distribution testbed for Space Station is presented. The system consists of six resonant inverters, a one-hundred-meter transmission line, and three load receivers: a dc receiver, a bidirectional receiver, and an ac receiver. A model library is generated characterizing all system components. The system's local and global behaviors are investigated using the EASY5 dynamic analysis program.

Tsai, Fu-Sheng↗

Constant-frequency, clamped-mode resonant converters

Two novel clamped-mode resonant converters are proposed which operate at a constant frequency while retaining many desired features of conventional series- and parallel-resonant converters. State-plane analysis techniques are used to identify all possible operating modes and define their mode boundaries. Control-to-output characteristics are derived that specify the regions for natural and forced commutation. The predicted operating modes are verified using a prototype circuit.

Tsai, Fu-Sheng↗