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We tackle the problem of sharing eHealth data across different jurisdictions. As a general rule, and due to the sensitive nature of the information, different national regulations impose severe limits on what can be exchanged, even in case of emergencies. Furthermore, different systems in different jurisdictions do not communicate. We propose BRUE as a scheme that allows eHealth data to be securely exchanged, with the data subject always in the position of mediation. We combine several technologies, namely, Blockchain, OAuth and User-Managed Access, and concept Receipts, to achieve our aim.

In this paper, an LCL filter is proposed to replace L-type filter in a dc/dc converter for battery charging applications. The merits of using an LCL filter are compact size, and extremely low ripple of charging current. The ripple free charging can reduce the heat generated by the ripple of the charging current and improve the battery lifetime. Filter based controller is proposed to solve the control loop instability issue caused by LCL filter. Low-pass filter and notch filter based controllers are designed and compared. The controller robustness to the variation of the filter parameters is investigated. The proposed system and control methods are verified by simulation and experiment.

Using hperspectral remote sensing information method to extract geothermal resources information, choosing different objects feature parameters and classification methods, such as false color composite and enhanced processing, single-band pseudo-color image synthesis, spectral angle mapping, linear spectral unmixing, extracting geothermal energy information, achieved good results.

Solid state transformer (SST) is considered the key unit for power processing and conversion in the future distributed renewable energy network. The role of SST is to enable the active management of distributed energy resources, energy storage devices and different type of loads in a distribution grid. Inverter stage of SST supplies sinusoidal voltage to the users. In this paper an improved inductor current control based on active harmonics injection is proposed to overcome the drawback of inferior performance of conventional inductor current feedback control for the nonlinear loads. The inductor current overshoot during the load transient is investigated by using both capacitor current feedback control and inductor current feedback control. The inductor current feedback control has the capability to limit current overshoot even with a smaller inductor, which shows the potential to further reduce the size and weight of the passive components.

The digital controller is the “heart” of the PV system: it will track the maximum power point (MPP) and regulates the output current to meet the utility inter-connection standards. This paper introduced a new approach “model based design” to develop digital controller for PV inverter. This design methodology filled the gap between computer simulation and hardware implementation of the digital controller and made an easy way for the implementation of complex and high level algorithm in a digital signal processor (DSP) [1]. With the model based technique, a double loop current controller is designed based on inverter's small signal model in D-Q rotating frame. Also a Perturbation & Observation (P&O) algorithm [2] is implemented for maximum power point tracking (MPPT). The digital controller model has been verified by simulation in MATLAB. Then the controller has been implemented with a TI's DSP TMS320F28335 and tested on a PV inverter prototype with solar panels.

In this paper, a bi-directional battery charger is applied as an interface between plug-in hybrid electric vehicles and the grid. The major issue of using power electronics interface for grid integration of PHEVs is high frequency resonance. This resonance is caused by a high order filter, which is composed of the charger's LC filter and the grid impedance. An active damping method is proposed to mitigate the resonance. The modeling and controller design are presented. The damping performance to both the converter output harmonics and the grid harmonics are analyzed. The proposed controller can effectively reduce the high frequency resonance on the grid current. The proposed method is verified by the simulation and experiment.

This paper proposes a simplified current controller for any general N-level converter based on space vector (SV) theory. Through the presented mapping technique between the subhexagon of the N-level converter and the hexagon of the two-level converter, the proper output voltage vector of the N-level converter can be identified to suppress harmonic current content in steady state and attain fast current response in transient state. Meanwhile, the redundant switching states of the voltage vectors can be used to reduce or balance the device power losses, and regulate floating capacitor voltages. The controller complexity is greatly reduced due to the use of very simple lookup tables, thus it can be easily extended to any general N-level converter. The proposed scheme is explained for a five-level active NPC converter and the simulation results are presented to prove its correctness.

There is a growing interest on plug-in hybrid electric vehicles (PHEV's) due to energy security and green house gas emission issues, as well as the low electricity fuel cost. As battery capacity and all-electric range of PHEV's are improved, and potentially some PHEV's or EV's need fast charging, there is increased demand to build high power off-board charging infrastructures. A charge station architecture for municipal parking decks has been proposed, which has a DC microgrid to interface with multiple DC-DC chargers, distributed renewable power generations and energy storage, and provides functionalities of normal and rapid charging, grid support such as reactive and real power injection (including V2G), current harmonic filtering and load balance. Several non-isolated bidirectional DC-DC converters suited for charge station applications have been reviewed and compared, as the major focus of this paper. Half bridge converter is a good candidate but it is difficult to maintain high efficiency in wide battery pack voltage range. A variable frequency pulse width modulation (VFPWM) scheme is proposed to mitigate this issue. Finally three-level bi-directional DC-DC converter is suggested to be employed in this application. A 10kW prototype verifies that 95.1–97.9% full load efficiency can be achieved in charging mode with 180–360V battery pack voltage. In addition, the inductor size is only one third of the half bridge counterpart, which is a great advantage for high power converters.

The Solid State Transformer (SST) is one of the key elements proposed in the National Science Foundation (NSF) Generation-III Engineering Research Center (ERC) “Future Renewable Electric Energy Delivery and Management” (FREEDM) Systems Center. The SST is used to enable active management of distributed renewable energy resources, energy storage devices and loads. In this paper, the Generation-I SST single-phase 20kVA, based on 6.5kV Si-IGBT is proposed for interface with 12kV distribution system voltage. The SST system design parameters, overall system efficiency, high frequency transformer design, dual active bridge converter, auxiliary power supply and gate drives are investigated. Design considerations and experimental results of the prototype SST are reported.

The main objective for a grid-tied photovoltaic (PV) inverter is to feed the harvested energy from PV panels to the grid with high efficiency and high power quality. A digital controller is the “heart” of the PV system: it calculates the maximum power point (MPP) and regulates the output current to meet the utility inter-connection standards. This paper introduced a new approach “model based design” to develop current controller for PV inverter. This design methodology filled the gap between computer simulation and hardware implementation of the digital controller and made an easy way for the implementation of complex and high level algorithm in a digital signal processor (DSP) [1]. The inverter's small signal model in D-Q rotating frame is derived and a double loop current controller is designed. The performance of the developed controller has been verified by both of the simulation in MATLAB and experimental results from a 2kW single phase PV inverter prototype.

Vehicle-to-Grid (V2G) technology is one promising feature of plug-in hybrid electric vehicles. A comprehensive comparison between the three-leg converter and H-bridge converter applied to vehicle-to-grid applications is made. This comparison focuses on the converter's passive components, power consumption and control effort. A three-leg converter with an LCL filter designed for a typical American household electric system is proposed. This converter has both vehicle-to-grid function and stand-alone function with high performance.

A new multi-function bi-directional battery charger for plug-in hybrid electric vehicles (PHEV) is proposed based on the power circuitry configuration of an American house. This bi-directional charger can achieve three functions including battery charging, vehicle to grid (V2G) and vehicle to home (V2H), all of which are the major research areas of PHEV's integration with the power grid. The integration infrastructure and practical design issues are analyzed. The multiple control loop designs are presented for the three operation modes. Simulation and experimental results verify the functions and performance of the proposed charger. With the capability of achieving multiple functions, the bi-directional charger will contribute and enhance grid related research of PHEVs.

The distributed power flow controller (DPFC) based-on Emitter Turn-Off (ETO) light converter is one newly proposed solid state power electronics technology based Flexible AC Transmission System (FACTS) devices which is effective to control the active power flow through the transmission lines. This modular DPFC has low cost, high reliability and makes it possible to have the transformerless connection to the existing power grid. In this paper, the development and analysis of modeling techniques and feedback schemes based on per phase control of DPFC are proposed. The simulation results and experimental results show the consistency of the propose model and the feasibility of the feedback control design for the DPFC per-phase operation.

A new bi-directional power converter for Plug-in Hybrid Electric Vehicles (PHEV) is proposed based on a typical household circuitry configuration. This converter can achieve three major functions: battery charger mode, vehicle to grid mode (V2G) and vehicle to home mode (V2H), which are the main topics of integration of PHEVs with the grid. The detailed converter design is presented. An improved AC/DC controller is proposed in order to achieve low input current harmonics for the charger mode. The Proportional resonant+harmonics selective compensation method is utilized for the V2G mode, and capacitor current feedback and proportional resonant control methods are adopted for the V2H mode. Compared with conventional PI controllers, the proposed controllers greatly enhance the grid-connected converter's performance in the aspects of low harmonics output and robustness against background noise.

W kV SiC MOSFETs are currently under development by a number of organizations in the United States with the aim to enable their applications in high voltage high frequency power conversion applications. The aim of this study is to demonstrate their high frequency high temperature operation capability in the application of a DC/DC boost converter. A DC/DC boost converter based on a 10 kV 10 A SiC MOSFET and a 10 kV 5A Junction Barrier Schottky (JBS) diode is designed and tested for continuous conditions up to a switching frequency of 25 kHz, an output voltage of 4 kV, an output power of 4 kW and a junction temperature of 174degC for the SiC MOSFET. In the steady state of the 20 kHz boost converter operation, the input power is 4335 W, the output power is 4030 kW and the efficiency is 93%. The power loss analysis shows the total power loss in the 30.45 mm2 SiC MOSFET is 115 W, and the operating junction temperature of the SiC MOSFET is 140degC at the 20 kHz switching frequency. The power losses and the junction temperature of the SiC MOSFET as a function of the switching frequency, load current and input voltage in the boost converter are investigated extensively. The fast switching, low loss and high temperature operation capability of 10 kV SiC MOSFETs demonstrated in the DC/DC boost converter make them attractive in high frequency high voltage power conversion applications.