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The use of electronic equipment and other dc-compatible appliances in homes and offices is increasing at a very fast rate, as well as the distributed generation of energy. These two statements will most likely trigger, in a near future, the adoption of district-scale dc grids, connecting dc microgeneration plants and consumers, in an effort to cut the number of conversion steps required to deliver power to dc appliances. DC-DC converters will be fundamental in these systems, allowing the establishment of several voltage levels. The reliability of these converters plays a critical role, ensuring service continuity of the loads connected to them. With the increment of reliability in mind, this paper proposes a simple yet effective open-circuit fault diagnostic method suitable for interleaved dc-dc boost converters, but equally functional for other dc-dc converter topologies. The improvements introduced in this paper greatly simplify the diagnostic action, while making the correct diagnostic of faults independent of the switching duty cycle. Moreover, an alternative reconfiguration scheme is proposed to mitigate the adverse impacts of such faults. To prove the effectiveness of these strategies, a three-phase interleaved boost converter prototype was used in the experiments., Paper 2018-IPCC-0961.R1, presented at the 2017 IEEE 11th International Symposium on Diagnostics for Electrical Machines, Power Electronics and Drives, Tinos, Greece, Aug. 29–Sep. 1, and approved for publication in the IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS by the Industrial Power Converter Committee of the IEEE Industry Applications Society. This work was supported in part by the European Regional Development Fund through the Operational Programme for Competitiveness and Internationalization (COMPETE 2020), under Project POCI-01-0145-FEDER-029494, and in part by National Funds through the FCT—Portuguese Foundation for Science and Technology.

A Phase-Shift-Modulation (PSM) technique is proposed for an Active-Bridge-Active-Clamp (ABAC) topology. This topology is aimed for high power more-electric-aircraft applications. The proposed PSM has a complete switching harmonics cancellation on the low voltage terminal, independently of the operating conditions by effectively interleaving inductor currents. This results in a DC current at the low voltage terminal without any AC components, thus minimizing the passive filtering requirements. Additionally, when terminal voltages vary from their nominal values, the maximum power transfer capability of the ABAC converter can be greatly improved by using the proposed PSM. In this paper, the limitations of the conventional modulation technique for the ABAC converter are introduced and analysed. Then, a PSM scheme is proposed, which can provide high quality power on the low voltage terminal whilst maintaining high power transfer capability and efficiency in a wide operating range. The theoretical claims are validated by both simulation and experimental results on a 10kW 270V/28V ABAC converter.

In the context of IoT applications, together with the use of deep-submicron technologies as FinFET, this paper presents a revision of the gm/ID methodology for radio-frequency analog front-end circuits. Particularly, this methodology is applied for the design of LC-VCOs in the 5.8-GHz band using 20-nm FinFET transistors. To incorporate the FinFET model into the design flow, a semi-empirical model is extracted from electrical simulations. To show the good performance of the methodology, an LC-VCO design, picked from the calculated design maps, is electrically simulated, achieving good match regarding oscillation frequency and phase noise.

Piezoelectric vibration energy harvesters have drawn much interest for powering self-sustained electronic devices. Furthermore, the continuous push toward miniaturization and higher levels of integration continues to form key drivers for autonomous sensor systems being developed as parts of the emerging Internet of Things (IoT) paradigm. The synchronized switch harvesting (SSH) on inductor and synchronous electrical charge extraction are two of the most efficient interface circuits for piezoelectric energy harvesters; however, inductors are indispensable components in these interfaces. The required inductor values can be up to 10 mH to achieve high efficiencies, which significantly increase overall system volume, counter to the requirement for miniaturized self-power systems for IoT. An inductorless bias-flip rectifier is proposed in this paper to perform residual charge inversion using capacitors instead of inductors. The voltage flip efficiency goes up to 80% while eight switched capacitors are employed. The proposed SSH on capacitors circuit is designed and fabricated in a 0.35- $\mu \text{m}$ CMOS process. The performance is experimentally measured and it shows a 9.7 $\times $ performance improvement compared with a full-bridge rectifier for the case of a 2.5-V open-circuit zero-peak voltage amplitude generated by the piezoelectric harvester. This performance improvement is higher than most of the reported state-of-the-art inductor-based interface circuits, while the proposed circuit has a significantly smaller overall volume enabling system miniaturization.

This paper presents a novel design calculation scheme for low voltage Modular Multilevel Converters. One of the most important design values is to estimate the lifetime of the electrolytic cell capacitor. Therefore, a novel calculation method for the arm capacitor root mean square current is presented. Additionally, a new algorithm to estimate the power losses without a detailed simulation of the switching events is introduced. The results from these calculations are used to construct a low voltage Modular Multilevel Converter with 8 cells per arm.