J. A. Carrasco

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This paper describes a baseline solution of a Power Conditioning and Distribution Unit (PCDU) for Electrical Propulsion (EP) systems. The solution adopted uses two high efficiency, low-mass power regulators; a solar array regulator (SAR) based on the classical Sequential Switching Shunt Regulator with Maximum Power Point Tracking (MPPT) capability followed(More)
This work describes the principles of the sequential switching shunt series regulator, S4R, an innovative solution proposed by the European Space Agency and other partners to power the next generation of high power telecommunications satellites. A comparative study between, the S4R regulated bus vs. the traditional option, the sequential switching shunt(More)
A novel maximum power point estimator (MPPE) for photovoltaic solar arrays is proposed, evaluated and implemented. Unlike maximum power point trackers (MPPT), the MPPE extracts the solar array maximum power with no tracking process. The operation is based on solving the solar array electronic equivalent model by a microcontroller in real time. Only four(More)
This letter characterizes, in terms of the bandwidth and limit cycle frequency of its constituent subsystems, the sequential switching shunt series regulator -S/sup 4/R, a high-efficiency, low-mass and volume power cell devised to power the next generation of regulated power buses in telecommunication spacecrafts. Transconductance power source modeling is(More)
This paper presents a post-regulator based on the use of a controlled transformer, which adds or subtracts an additional voltage to the output filter of a converter in order to regulate its output voltage. So, their actuation is complementary to that of more known post-regulators, such as the magnetic amplifier (magamp) and synchronous switch post-regulator(More)
This work describes the principles of the sequential switching shunt regulator-digital shunt regulator, S3R-DSR, a novel approach to implement the solar array regulator. This is especially devoted to overcome the problems derived from the high solar array parasitic capacitance that exhibits the present (high power) telecommunications satellites
In this work, two alternative printed antennas for wireless sensor networks applications in the ISM band are presented. The antennas are based on the well- known Yagi-Uda antenna and the principal difference between them is on the printed dipole design; in only one face of the substrate or in both faces. The design has been performed by using an in house(More)
This work deals with the effect produced by the solar array capacitance on the sequential switching shunt regulator, S4R. In the past, silicon solar cells were widely used with practically no effect upon the solar array regulator, so that the solar array capacitance was a minor problem in the design. Nowadays, the usage of triple junction GaAs solar cells(More)
The sequential switching shunt series regulator-S4R, is a fully regulated bus and battery charger power cell devised for high power telecommunication spacecrafts. A mathematical characterization is obtained by means of the modeling of its power sources as nonlinear transconductances. Simulations and experimental measurements are presented to check the model(More)