This paper reports the novel design of a touch mode capacitive pressure sensor (TMCPS) system with a wireless approach for a full-range continuous monitoring of ventricular pressure. The system consists of two modules: an implantable set and an external reading device. The implantable set, restricted to a 2 × 2 cm2 area, consists of a TMCPS array connected with a dual-layer coil, for making a reliable resonant circuit for communication with the external device. The capacitive array is modelled considering the small deflection regime for achieving a dynamic and full 5–300 mmHg pressure range. In this design, the two inductive-coupled modules are calculated considering proper electromagnetic alignment, based on two planar coils and considering the following: 13.56 MHz frequency to avoid tissue damage and three types of biological tissue as core (skin, fat and muscle). The system was validated with the Comsol Multiphysics and CoventorWare softwares; showing a 90% power transmission efficiency at a 3.5 cm distance between coils. The implantable module includes aluminum- and polyimide-based devices, which allows ergonomic, robust, reproducible, and technologically feasible integrated sensors. In addition, the module shows a simplified and low cost design approach based on PolyMEMS INAOE® technology, featured by low-temperature processing.

A solar cell model that combines the photovoltaic and electro-thermal processes is proposed. The bond graph methodology is used as a reference frame, allowing the representation of the whole structure in a unified approach. The solar cell structure is modeled as a three-dimensional object allowing observation of a nonuniform solar radiation on the surface. Subsequently, the proposed model is used in the solar cell design.

In this paper, an alternative strategy for the design of a bidirectional inductive power transfer (IPT) module, intended for the continuous monitoring of cardiac pressure, is presented. This new integrated implantable medical device (IMD) was designed including a precise ventricular pressure sensor, where the available implanting room is restricted to a 1.8 × 1.8 cm2 area. This work considers a robust magnetic coupling between an external reading coil and the implantable module: a three-dimensional inductor and a touch mode capacitive pressure sensor (TMCPS) set. In this approach, the coupling modules were modelled as RCL circuits tuned at a 13.56 MHz frequency. The analytical design was validated by means of Comsol Multiphysics, CoventorWare, and ANSYS HFSS software tools. A power transmission efficiency (PTE) of 94% was achieved through a 3.5 cm-thick biological tissue, based on high magnitudes for the inductance (L) and quality factor (Q) components. A specific absorption rate (SAR) of less than 1.6 W/Kg was attained, which suggests that this IPT system can be implemented in a safe way, according to IEEE C95.1 safety guidelines. The set of inductor and capacitor integrated arrays were designed over a very thin polyimide film, where the 3D coil was 18 mm in diameter and approximately 50% reduced in size, considering any conventional counterpart. Finally, this new approach for the IMD was under development using low-cost thin film manufacturing technologies for flexible electronics. Meanwhile, as an alternative test, this novel system was fabricated using a discrete printed circuit board (PCB) approach, where preliminary electromagnetic characterization demonstrates the viability of this bidirectional IPT design.

A PhotoVoltaic (PV) system with a Linear Parametric Varying (LPV) average model of a buck converter modelled by bond graph methodology, is considered. It is assumed that the voltage generated by the PV panel is a smooth function of time under changes in atmospheric conditions. A model reference is proposed representing the PV system with buck converter operating at the Global Maximum Power Point (GMPP). An LPV control is designed, and an algorithm is proposed in a model reference tracking control configuration assuring that the PV system with buck converter tracks the proposed model reference and hence guaranteeing that this system operates at the GMPP. The proposed algorithm changes the voltage reference based on the power measurement of the PV system assuring that this reference represents the GMPP under shading conditions. The LPV control is designed for an average model of the buck converter solving a feasibility problem based on linear matrix inequalities that assure quadratic stability and minimize a quadratic criterion. The feedback system is tested under shading conditions, and its performance is compared with a standard Perturb and Observe method and with an ideal algorithm based on the irradiance measurement in each section of the PV system.

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