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The positive output elementary superlift-Luo converter (POESLLC) is a type of dc/dc converter. This dc/dc converter has an attractive advantage of a high voltage transfer gain as compared with other conventional dc/dc converters. Because of the voltage and load variations and also switching operation, the dynamic and static performances of the POESLLC are nonlinear and time varying. In order to achieve an excellent performance, a nonlinear controller is required. In this paper, a robust and fast response controller for voltage regulation of a POESLLC is presented. A proportional integral and pulse width modulation sliding mode controller are combined to control a third-order POESLLC. The proposed controller can be applied in the continuous conduction mode. Some simulations and experimental results are presented to show the effectiveness of the developed controller in different operating conditions. Furthermore, it will be shown that the developed controller is successful in suppressing the steady-state error of the output voltage of the POESLLC as well as the number of reduction of sensors. [ABSTRACT FROM PUBLISHER]

The feasibility of a spacecraft power system using lithium-ion capacitors (LICs) as the energy storage source is analyzed and compared with a system that uses lithium-ion batteries (LIBs). The mass of the LIB- and LIC-based power systems, including photovoltaic (PV) arrays, are compared at various depth of discharge (DoD) levels. The LIC-based system at a deep DoD of 60–80% can be comparable with the LIB-based system at a DoD more shallow than 20% with respect to the system mass. [ABSTRACT FROM PUBLISHER]

Presents a study which determined the parameters for four different capacitors from discharge data using standard laboratory equipment such as an oscilloscope. Calculations of equivalent parallel resistance and equivalent series resistance (ESR); Sensitivity of capacitance and ESR to charge rate and voltage; Evaluation of capacitance as a function of terminal voltage.

The design and development of a dc to dc buck converter capable of operating up to 275?C is presented. The control circuitry design is based on the vee-square (V^2) control mechanism. The system converts a raw dc input voltage in the range of 15 V to 25 V to a stepped-down and filtered output voltage in the range of 1.5 V to 18 V. A custom designed user programmable control circuitry is implemented on the low leakage, radiation tolerant silicon-on-insulator technology. Silicon carbide junction field effect transistors (JFETs) are used as power switches to sustain extreme operating temperature. The system is prototyped on the aluminum nitride substrate to meet packaging requirements. Design considerations for the planar transformer coupled gate drive are specifically addressed. The system performance is studied based on a 20 V to 3.3 V prototype converter. The demonstrated system has potential market in extreme environment applications like deep space explorations, down-hole geothermal and deep gas reservoir management, etc. [ABSTRACT FROM PUBLISHER]