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For the fully resonant wireless power transfer (WPT) system, the high coupling of the converter and the resonant network introduced many problems, such as frequency splitting, the power curve peak limit, and the strict switch strategy. To solve these problems, this paper proposed a new six-switch topology based on the full–-bridge converter. With the unique structures containing two capacitor-isolated switches and a source-isolated diode, the system decouples the converter and the resonant network, and its modes have been decoupled, called the independent power injection and free resonance WPT (IPIFR–WPT) system. The capacitor-isolated switches and the source-isolated diode make the converter operate only when the voltage on the primary capacitor is equal to the source voltage, and the source will be isolated by the diode when the capacitor voltage is great than the source, which provides a wide time margin for the switches of the converter to turn on in advance. In this margin, the operation point is self-determined the same whenever the switches turn on so that the system’s performance is consistent. Based on this characteristic, the system can self-adapt a dynamic change in system parameters, with at least 15% tolerance for the coupling coefficient and 14% for the load resistance.

Large share of solar energy imposes a higher system flexibility to resolve the increased demand/supply imbalance due to the inherent intermittency and variability of the resource. In this work, we demonstrate that the additional solar-induced flexibility requirement can be fully provided by a special kind of solar farms, namely flexible PV. These plants are able to provide ancillary services by proactive generation curtailment and storage power injection and they can be managed exactly as the secondary reserve currently used. At the current and future penetration levels, we sized the flexible PV fleet required to reduce the Italian imbalance by 36 % (with respect to its 2016 value) while keeping the curtailment at 6 % of the national PV generation. We show how this result can be achieved at an equal or lower dispatching cost than current cost (depending on the solar share). In addition, we found that a fleet composed of many flexible PV plants with different capacity randomly distributed throughout the country provides an optimal solar regulation performance. Finally, we showed that the effectiveness of the proposed imbalance mitigation strategy depends only slightly on the year-specific load, wind, PV and energy prices profiles used to size the capacity of the flexible fleet.

As plentiful roof-top photovoltaic (PV) panels and battery energy storage systems (BESSs) have been installed in residential houses, smart homes which provide reliable and cost-efficient energy for customers have been increasingly developing. This study proposes a smart home coordinated operation framework consisting of day-ahead scheduling of a BESS and deferrable appliances as well as real-time BESS affinely adjustable control. The scheduling aims to minimise daily energy usage bills and the affinely adjustable control aims to eliminate fluctuations of intermittent PV output and at-will uncertain appliances. This study proposes an affinely adjustable robust energy management system (AAREMS) which can optimise the day-ahead scheduling with full consideration of the real-time BESS control under uncertainties. Moreover, affinely adjustable robust counterpart formulation is developed to solve the AAREMS under the worst case of real-time uncertainty realisation. The simulation results verify the high efficiency of the proposed AAREMS in minimising the energy usage bills for the customers and providing certain and invariable power injection for the utility grid.

This paper presents a new computational attractive interval power flow (PF) approach with correlated uncertain power injections while maintaining high estimation accuracy. The key idea is to integrate the ellipsoid convex model with the evidence theory. This allows us to effectively account for uncertain power injection correlations and eliminate irrelevant focal elements, yielding significantly improved computational efficiency. Extensive comparisons with other approaches demonstrate its effectiveness under various conditions.

Corey A Kemper,1 Casper Mihl,2,3 Bibi Martens,2,3 Michael C McDermott,2,4 Babs MF Hendriks2,3 1Bayer U.S. LLC, Bayer Pharmaceuticals, Radiology R&D, Indianola, PA, USA; 2Department of Radiology & Nuclear Medicine, Maastricht University Medical Center, Maastricht, the Netherlands; 3Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, the Netherlands; 4Bayer AG, Radiology R&D, Berlin, GermanyCorrespondence: Corey A Kemper, Bayer U.S. LLC, Bayer Pharmaceuticals, Radiology R&D, 1 Bayer Dr, Indianola, PA, USA, Tel +1 412 225 3907, Email corey.kemper@bayer.comPurpose: To compare an investigational device (MEDRAD® Centargo CT Injection System, “Centargo”) to the currently available MEDRAD® Stellant CT Injection System (“Stellant”), in terms of efficiency, injector performance, and user satisfaction.Patients and Methods: A total of 425 patients at two sites were enrolled; 198 patients in phase one, a randomized study (98 Stellant and 100 Centargo). The second observational phase included 227 patients who were injected with Centargo. Phase one recorded times for setup, disassembly, and patient changeovers. Demographic data, subjective image quality, and injection parameters were collected. Phase two assessed usability via a questionnaire provided to all end-users of both systems (radiographers).Results: Patient changeover times were statistically significantly faster with Centargo (15.4s ± 8.7s vs 53.7s ± 19.6s, p < 0.001). Centargo day-setup times were similar to Stellant (138.1s ± 92s vs 151.8s ± 30.6s, p = 0.33) and end-of-day-disassembly times were significantly slower (60.6s ± 27s vs 17.1s ± 12.9s, p < 0.001). Based on four different scenarios modelling patient throughput, the projected time savings with Centargo over Stellant was 40– 63%, with the highest efficiency improvements for higher throughputs and the use of larger contrast medium bottles. Both Centargo and Stellant usability averaged between “Very Easy” and “Easy” in all responses to the questionnaire. There were no instances of interrupted injections due to communication loss or detected air and no insufficient images due to injector performance. No safety issues were identified.Conclusion: Centargo was able to demonstrate improved efficiency as compared to Stellant while maintaining injector performance and high usability scores.Keywords: power injection, efficiency, time savings, usability, Centargo

This paper deals with power injection on single phase grid connected inverter. The simple method is introduced to understand the concept of grid connected systems. A phase Lock Loop (PLL) method estimates the phase-angle of grid system. The output of PLL is used to defines Iref , and the current of inverter becomes a feedback (IL). Both current are derived to produce PWM using current mode controller method. As long as the grid system on fault condition like voltage distortion, therefore the single-phase inverter that connected into the grid should change the role and keep stabilization. The voltages sag and swell are the possible conditions that occurred on a power system. Voltage Sag is an event where the line voltage decreases from the nominal line-voltage for a short period of time. Voltage swell is the event when the line voltage increase from the nominal line voltage. By using PSIM software, the injection and absorption of power into a grid system is verified during a voltage sag, swell, and normal. The simulation shows voltage grid vg, current inverter iinv, current grid, active power P, reactive power Q. The waveform of the measured parameter is analized to define the role of inverter toward grid. the The result shows performance of the proposed inverter to absorb reactive power during swell, and inject reactive power when sagging.

This paper aims to propose the vector form implementation into three-phase power flow analysis. The developed algorithm is based on Newton-Raphson method with voltage is represented in rectangular coordinate. The Python programming language and its mathematical libraries are used in this works. Three-phase power flow analysis in vector form utilizes sparse matrix ordering algorithm, so the elements of the coefficient correction matrix can be rearranged easily. This method was used to solve three-phase power flow for balance or unbalance network in two actual distribution system feeders in Lampung, i.e. 119 nodes and 191 nodes. Comparison with traditional Newton-Raphson method (non-vector) shows the vector form is able to solve computation up to eight times faster than non-vector. Keywords : Three-phase power flow, Vector form, Newton-Raphson, Rectangular, Python

In the AC/DC hybrid microgrids equipped with power electronic transformer (PET), different AC grids and DC grids are connected through multiport PET to operate the entire network in a secure and economic manner. This paper proposes a decentralized optimal power flow model, considering the multiport coordinated control strategy of PET, for running autonomous AC/DC hybrid microgrids. To optimize the power flow in the network, the steady state model of PET is established, including voltage source converter power injection model and Kriging model. By introducing a secondary droop control layer can realize the autonomous operation of AC/DC hybrid microgrids and increase the utilization efficiency of distributed generations. Then using the analytical target cascading approach, each AC/DC sub-microgrid is regarded as different autonomous subjects. The distributed PET is as power coupling node and information interaction node to decompose the optimal problem of AC/DC hybrid microgrids equipped with PET which is solved in parallel. The obtained subproblems for these grid levels are solved with a nested solution process. The simulation results verify the correctness and effectiveness of the proposed model in this paper.

This paper characterizes the immunity of I/Os under different supply voltages for fault-tolerant circuit designs against electromagnetic interference. The direct power injection approach is used as a means to characterize the immunity of circuits. In this work, the immunity characterization has been performed under two scenarios: (1) an input buffer of a Field Programmable Gate Array (FPGA) followed by a single flip-flop, and (2) the FPGA input buffer followed by a redundancy-based fault-tolerant circuit. The experimental results show that when downscaling the supply voltage through a set of nominal values (i.e., 3.3, 2.5, 1.8, 1.5, 1.2 V), the immunity of I/Os is decreased from the highest level at 3.3 V to the lowest at 1.2 V. Particularly, the maximum difference in the immunity is about 16.8 dB at the frequency of 600 MHz. Moreover, experiments demonstrate that I/O buffers followed by the redundancy-based fault-tolerant circuit can improve the immunity of the circuit up to 4 dB below the frequency band of 400 MHz. Thus, the redundancy-based fault-tolerant circuit can support I/Os to operate reliably in the harsh environment.

Growing penetrations of distributed energy resources (DERs) increase the power injection variability in distribution systems, which can result in power quality issues such as voltage unbalance. To measure unbalance, organizations such as IEC, NEMA and IEEE define phase unbalance in their power quality standards. However, the definitions in these different standards are not consistent, and voltages that are considered acceptable by one standard may violate good practices defined by another standard. To address this issue, this paper provides analytical comparisons of the most common voltage unbalance definitions, which are supplemented with numerical simulations. The analytical relationships suggest that it is possible to approximately bound the symmetrical-component-based voltage unbalance factor (which depends on the magnitude and relative phase angle) by limiting the line-to-line voltage unbalance, whereas applying line-to-ground voltage unbalance definitions neglects all information about phase angle offsets.

Venous air embolism as a complication of contrast media administration from power injection systems in CT is found to occur in 7%-55% of patients, impacting patient safety, diagnostic image quality, workflow efficiency, and patient and radiographer satisfaction. This study reviews the challenges associated with reactive air management approaches employed on contemporary systems, proposes a novel air management approach using proactive methods, and compares the impact of reactive and proactive approaches on injected air volumes under simulated clinical use.Injected air volumes from three power injection systems were measured under simulated clinical use via custom air trap fixture. Two of the systems employed reactive air management approaches, while a new system implemented the proposed proactive air management approach.The proactive system injected significantly less air (average of 0.005 mL ± 0.006 mL with a maximum of 0.017 mL) when compared to two systems with reactive approaches (averages of 0.130 mL ± 0.082 mL and 0.106 mL ± 0.094 mL with maximums of 0.259 mL and 0.311 mL, respectively) (p0.05). CT images were taken of static and dynamic 0.1 mL air bubbles inside of a vascular phantom, both of which were clearly visible. Additionally, the dynamic bubble was shown to introduce image artifacts similar to those observed clinically.Comparison of the injected air volumes show that a system with a proactive air management approach injected significantly less air compared to tested systems employing reactive approaches.The results indicate that the use of a proactive approach could significantly reduce the prevalence of observable, and potentially artifact-inducing, venous air embolism in contrast-enhanced CT procedures.

This paper presents a theoretical study of damping, synchronizing and inertial control laws, implemented using controllable power injection devices like HVDC, FACTS or renewable-energy/storage systems which have power-electronic grid interfaces. The approach is to use a simplified dynamical model of a power system to arrive at generalized results regarding the effect of the strategies on the electro-mechanical dynamics of the system. These results are not dependent on the size, network topology and operating condition of the power system. This paper presents a differential-algebraic formulation and generalized eigenvalue analysis to facilitate a unified study of the effects of the control laws on the electro-mechanical modes. The damping, synchronizing and inertial control laws can themselves be extended to include the possibility of mutual-damping, synchronizing and inertial effects when multiple devices are present. The control laws are not only simple and intuitive, but also are found to have a predictable and generally beneficial impact on the electro-mechanical dynamics of the grid, even when detailed models are considered.

The objective of this paper is to improve the voltage profile of the grid in pertinence to grid due to power injection from distributed solar photovoltaic (PV) arrays. Weak grids are modeled as worldwide adaptation of net metering, transactive energy systems, and the possibility of further deterioration of power quality with higher grid penetration. In this paper, a solar PV integrated weak distribution grid modelled as the PV arrays being frequently connected in rural areas, due to various reasons like cheap real estate and lack of accessibility. In this paper, three case studies of PV generation are simulated, i.e., scheduled solar PV generation less than load requirement, PV generation equal to load requirement, and PV generation more than load requirement, by considering the daily solar irradiation and load demand profiles of a residential area under study.

The increasing penetration of Renewable Energy Sources (RES), the liberalization of the electricity markets across the world and devices such as smart meters to realize bidirectional communication with centralized computer systems present the end-users of the power system withnew opportunities to decrease their electricity costs or become active electricity market participants. However, the intermittent nature of RES and dynamic electricity prices require tools against uncertainty to protect the end-users from under utilizing their assets. In this work, we examine theeffectiveness of Robust Optimization (RO)in maximizing the economic benefit of the owner of a home battery storage system in the presence of uncertainty in dynamic electricity prices. The advantage of the robust model is that it keeps its linear class, thus it is not too computationally intensiveto be included in the control algorithm of a residential energy storage controller. We examine the effectiveness of the RO model in doing dynamic electricity price arbitrage and in providing fast response to requests from an aggregating entity for power injection or absorption. In the use-case,the aggregating entity makes requests for flexibility and coordinates 100 such devices using a price signal. The results indicated that the RO approach can be beneficial for a non-conservative agent in the case of low daily price fluctuations. However, if the daily price fluctuations are higher, as in summer, the agent is better off by ignoring uncertainty in the dynamic electricity prices.

The rise in electrical power demand and corresponding transmission or distribution loss is affecting the efficiency of power delivery. A new method for loss allocation in radial distribution system based on proportional sharing is proposed. Based on allocated loss, optimal location of distribution generation (DG) is selected. After selecting the location, optimal size of DG is obtained for that location. Loss allocation to DGs is based on formation of two matrices, power contribution matrix and power sharing matrix. Loss share of DGs and loads are decided based on both power injection by DGs and loss minimisation due to presence of DGs. Results of the proposed method are shown on 69 bus radial distribution system.

This paper presents a novel method of hydro power plant operation, based on the control of the injectors&rsquo, or wicked gates opening time as a function of the upper reservoir level. In this way, a faster power injection, depending on the current water level on the upper reservoir, could be achieved. When this level is higher, the opening time could be shorter, hence, hydropower ramps could be steeper. Due to this control, frequency excursions and load shedding trips are smaller, thus the power quality is enhanced. This method has been tested and validated by computer simulations in a case study located in El Hierro island, Canary Archipelago (Spain). The simulations made show significant improvements, dependent on upper reservoir water level, in power quality.

Displacement of peripherally inserted central catheter (PICC) lines during contrast-enhanced computed tomography examinations is an underappreciated phenomenon. We report a case of iatrogenic PICC line displacement following the power injection of contrast during a computed tomography pulmonary angiogram. During the study, the PICC line was shown to move on 2 occasions, resulting in 2 nondiagnostic studies. We review the available literature on the topic and suggest possible strategies to avoid this phenomenon. Radiologists should be aware of PICC line migration, and it should become common practice to review the catheter tip position after computed tomography examinations.

This study presents a strategy using the synchronized output regulation method (SOR) for controlling inverters operating in stand-alone and grid-connected modes. From the view point of networked dynamic systems, SOR involves nodes with outputs that are synchronized but also display a desirable wave shape. Under the SOR strategy, the inverter and grid are treated as two nodes that comprise a simple network. These two nodes work independently under the stand-alone mode. An intermediate mode, here is named the synchronization mode, is emphasized because the transition from the stand-alone mode to the grid-connected mode can be dealt as a standard SOR problem. In the grid-connected mode, the inverter operates in an independent way, in which the voltage reference changes for generalized synchronization where its output current satisfies the required power injection. Such a relatively independent design leads to a seamless transfer between operation modes. The closed-loop system is analyzed in the state space on the basis of the output regulation theory, which improves the robustness of the design. Simulations and experiments are performed to verify the proposed control strategy.

WOS: 000375816300004, Statistical energy analysis is a widely used high frequency vibro-acoustic analysis tool. It is based on power flow balance between subsystems. Its accuracy mainly depends on precise determination of energy loss factors. In the paper, three different types of composite structures (point-connected I, L and T types) made of laminated plates are of concern to determine in-situ energy loss factors by using power injection methods (PIM). The results are compared with those obtained by approximate analytical determinations, thus accuracy of numerical and experimental PIM is discussed for point-connected composite plates. Analytical loss factors are computed by an iterative procedure to consider indirect coupling for the structures having more than two subsystems. (C) 2015 Elsevier Ltd. All rights reserved., Scientific and Technological Research Council of Turkey, TUBITAK [112M836], This study is a part of a research project with number of 112M836 which is supported by The Scientific and Technological Research Council of Turkey, TUBITAK.

Increased penetration of renewable energy leads to increased challenges for the Transmission System Operators (TSOs) to operate their system in a secure way. Through the limited means available to the TSOs to manage power flows in the system, reliability is jeopardized. Reliability must be managed differently, replacing the current ways of reliability management which fails as uncertainty increases. In this paper a novel risk-based approach of system operation is proposed that can be helpful for the TSOs to assess the confidence of system operation day-ahead, that is, the probability of the forecasted system to end up in an insecure state is calculated. This paper only focuses on violation of power flow constraints in the system. It also demonstrates the increase of this operation confidence using already installed Power Flow Controlling devices. It is shown that these devices aid in enhancing confidence of system operation by shifting power flows to a more optimal one in the light of generation uncertainty. The main emphasis is laid on preventive action. The proposed approach is demonstrated on test systems. ispartof: IEEE Transactions on Power Systems vol:30 issue:6 pages:3082-3092 status: published

The transmission network is an important part of the power system to deliver electrical energy from the power plant to the load, therefore the power system must be maximized to achieve optimal power flow, Unified Power Flow Control (UPFC) is one of the Flexible AC Transmission System (FACTS ) capable of controlling the power of the transmission line separately on electrical transmission and can be mounted on both the sender and the receiving end of the power. The UPFC power injection model to the transmission line is made in a power flow equation. In the Java Bali (Jali) 500 kV system analyzed by the Genetic Algorithm method, to produce a power injection that minimizes the active and reactive power losses of the transmission line without exceeding the UPFC device limit. In the Java Bali (Jali) 500 kV system analyzed by Genetic Algorithm method, the optimum UPFC value of Reactive Power injected to the system for bus 39 is 9695.593207MVar, bus 15 is 10598.78754 MVar, and on bus 37 is10755.88608 MVar. The total loss of channel power on the system prior to installation of UPFC is1815.775809 MW, while the total loss of channel power in the system after installing UPFC with GA is1537.391648 MW.

The simulation study was conducted for the new venous catheter with side holes of contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) to evaluate the infusion pressure on four contrast media and several injection speeds. All infusion pressure of the new venous catheter with side holes were less than 15 kg/cm2 as limitation of extension tube and also reduced the infusion pressure by 15% at the maximum compared to the catheter with single hole. The results suggest that the new venous catheter with side holes can reduce the infusion pressure by power injection of contrast-enhanced CT and MRI.

Many investigations have been published on the transferability of RF immunity test results between system and IC-levels. The RF signal level at DUT (Device under Test) inputs, i.e. either RF voltage amplitude or RF input current, is used as a reference value for the load on the DUT. Existing approaches analyze the DUT response as a function of the RF signal level at a single input pin, e.g. supply voltage. Sufficient accuracy of such an approach could be shown in several cases, but results are not sufficient as a general solution for complex DUT. This paper proposes both theoretical analysis and practical implementation of a DPI setup, where a disturbance, equivalent to system-level BCI setup, can be delivered to multiple DUT input ports.

This paper proposes a novel dc power-flow controller for a multiterminal HVDC system, which can be inserted in series on transmission lines to manage the dc power flow. Its key features include: 1) simpler circuit topology; 2) fewer components; and 3) the elimination of an external power supply and low-frequency high-voltage-insulation isolated transformer. A three-terminal HVDC system, including the dc power-flow controller, is studied and its operation principle and characteristics are analyzed. A simulation mode is built to test the feasibility and effectiveness of the proposed dc power-flow controller with cases of power injection step down, power loss of one terminal, and power-flow reversal. A three-terminal dc system is built in the lab to validate the dc power-flow controller. The results show that the proposed dc power-flow controller can enhance the performance and controllability of a multiterminal HVDC system.

The definition of Statistical Energy Analysis (SEA) models for large complex structures is highly conditioned by the classification of the structure elements into a set of coupled subsystems and the subsequent determination of the loss factors representing both the internal damping and the coupling between subsystems. The accurate definition of the complete system can lead to excessively large models as the size and complexity increases. This fact can also rise practical issues for the experimental determination of the loss factors. This work presents a formulation of reduced SEA models for incomplete systems defined by a set of effective loss factors. This reduced SEA model provides a feasible number of subsystems for the application of the Power Injection Method (PIM). For structures of high complexity, their components accessibility can be restricted, for instance internal equipments or panels. For these cases the use of PIM to carry out an experimental SEA analysis is not possible. New methods are presented for this case in combination with the reduced SEA models. These methods allow defining some of the model loss factors that could not be obtained through PIM. The methods are validated with a numerical analysis case and they are also applied to an actual spacecraft structure with accessibility restrictions: a solar wing in folded configuration.

Smart grid is critical to the success of next generation of power grid, which is expected to be characterized by efficiency, cleanliness, security, and privacy. In this paper, aiming to tackle the security and privacy issues of power injection, we propose an efficient and privacy-aware power injection (EPPI) scheme suitable for advanced metering infrastructure and 5G smart grid network slice. In EPPI, each power storage unit first blinds its power injection bid and then gives the blinded bid together with a signature to the local gateway. The gateway removes a partial blind factor from each blinded bid and then sends to the utility company aggregated bid and signature by using a novel aggregation technique called hash-then-addition. The utility company can get the total amount of collected power at each time slot by removing a blind factor from the aggregated bid. Throughout the EPPI system, both the gateway and the utility company cannot know individual bids and hence user privacy is preserved. In particular, EPPI allows the utility company to check the integrity and authenticity of the collected data. Finally, extensive evaluations indicate that EPPI is secure and privacy-aware and it is efficient in terms of computation and communication cost.

In automotive electronics, IC outputs are connected to a wide range of impedances generated by external circuitry or wiring harness. This load alteration, which is not fully covered by the established standard direct power injection (DPI), impacts the EMC immunity and should therefore be taken into account during susceptibility analyses. This paper introduces two S-parameter-based approaches which enable a simplified but sufficiently accurate assessment of the load dependency of the immunity. The proposed methods have been tested experimentally for a low-side driver and their validity is analyzed by comparison with measurement and large-signal simulation results.

Non-local measurements from wide area measurement systems can be used to synthesize feedback signals for FACTS or HVDC based power oscillation damping controllers. Although non-local feedback signals may have better damping influence than local feedback signals, they involve greater complexity and reduced robustness due to the possibility of partial or complete loss of communication. A composite control strategy is proposed in this paper, which uses both local and non-local feedback channels to achieve enhanced damping and improved robustness. Special local signals and their non-local equivalents are identified for series reactive and shunt real power injection devices, which facilitate the design of controllers with a simple structure and fewer parameters. Unlike modal speed signals, synthesis of these signals does not require an online eigen-solution. Case studies are presented which demonstrate the efficacy and robustness of this strategy.

Fair allocation of transmission loss among market participants is essential in the present restructured electricity markets. This paper proposes a direct method to find the loss allocation. The methodology is based on simple circuit laws and does not involve any assumptions. Considering the real power injection and real power loss contribution factors loss alloca- tion can be done. Case study of the proposed loss allocation methodology is conducted on an IEEE 14 bus system. Results are compared with the results of the existing methods in the literature.

Rationale and Objectives Modern computed tomographic scanners and examination protocols often require high injection rates of iodinated contrast media (CM). The purpose of this study was to investigate the maximum injection pressures (MIPs) with different CM at different temperatures in the most common intravenous cannula (IVC) sizes. Materials and methods Three IVC sizes, 22, 20, and 18 gauge, were evaluated. All examinations were performed with a pressure-limited (300 psi) power injector. The MIPs of three different CM (Solutrast 300, Imeron 350, and Imeron 400) were measured at room temperature (20°C) and at 37°C using increasing flow rates (1–9 mL/s). The intactness of the IVCs was checked after injection. Results Heating the CM led to reductions in injection pressures (P Conclusions Heating of CM effectively reduces MIPs using power injection in common IVCs. Although the manufacturer's suggested MIP was exceeded at higher flow rates, safe CM injection seems to be possible even in small cannulas using power injection. The compilation of the obtained data is meant to serve as guidance for future decisions on parameters of the power injection of iodinated CM.

Power injection variations that occur in power systems are generally nonlinear. A continuation power flow method with multiple nonlinear power injection variations is presented in this paper. To model the nature of nonlinear power injection variations, a piecewise-linear model is proposed to approximate the nonlinear model of power injections. The piecewise-linear model is studied and incorporated into continuation power flow, making it capable of handling nonlinear power injection variations. The impacts of linear as well as nonlinear load variations on the P-V curve, Q-V curve, and P-Q-V curve are numerically analyzed on test power systems. Numerical studies indicate that the direction of power injection variation can significantly affect the load margin and that the differences between uniform linear power injection directions and multiple nonlinear power injection variations can be significant. The importance of accurately modeling power injection variations on simulated power system quasi-state behaviors is stressed.

This paper introduces a complete simulation model of a direct power injection (DPI) setup, used to measure the immunity of integrated circuits to conducted continuous-wave interference. This model encompasses the whole measurement setup itself as well as the integrated circuit under test and its environment (printed circuit board, power supply). Furthermore, power losses are theoretically computed, and the most significant ones are included in the model. Therefore, the injected power level causing a malfunction of an integrated circuit, according to a given criterion, can be identified and predicted at any frequency up to 1 GHz. In addition to that, the relationship between immunity and impedance is illustrated. Simulation results obtained from the model are compared with measurement results, and these demonstrate the validity of this approach.

The unified power-flow controller (UPFC), with its unique combination of fast shunt and series compensation, offers a versatile device for the relief of transmission constraints. However, in order to realise this potential benefit, appropriate local and global power-system control strategies must first be developed. UPFC steady-state model and its implementation in normal (open-loop) power flow has been investigated by a number of investigators. This paper further develops the power-injection method based on optimal multiplier power flow for the steady-state control of UPFC for power-flow control and voltage support. The proposed power injection power-flow control can be effectively used to derive UPFC control parameters to achieve the required control objectives.

An original and reliable prototype injection setup has been developed in order to carry out accurate conducted susceptibility measurements up to 1.5 GHz. The prototype has been proposed as an alternative solution to typical injection setups such as a coupling capacitor, bias tee or cross-talk system, frequently used with the direct power injection standard IEC62132-4. Simple to build and mechanically sound, the prototype injection setup is used to merge continuous conducted electromagnetic disturbances with wanted signals by using merely a semi-rigid coaxial cable. It offers good stability on a wide frequency range. Furthermore, it is neither expensive nor complicated to build.

Made available in DSpace on 2016-03-02T13:04:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2015 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Elektroniczny konwerter mocy PEC używany jako interfejs rozproszonych źródeł energii został poszerzony o możliwości poprawy jakości energii. Prądowe źródło odniesienia bazuje na Teorii Zachowania Mocy CPT. In this work the functionalities of Power Electronic Converters (PEC) used as grid interface device for distributed generation sources are extended to deal with Power Quality (PQ) issues. It is proposed an alternative strategy to obtain current references based on the Conservative Power Theory (CPT). The proposed strategy contributes to the full exploitation of the PEC power capacity, allowing the PEC to act as a multifunctional device performing simultaneously selective compensation of PQ issues and power injection into the utility grid. Universidade Tecnológica Federal do Paraná (UTFPR), Campo Mourão, PR, Brasil Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP), Instituto de Ciência e Tecnologia de Sorocaba (ICTS), Departamento de Engenharia de Controle e Automação, Sorocaba, SP, Brasil Universidade Estadual de Campinas (UNICAMP), Faculdade de Engenharia Elétrica e de Computação (FEEC), Campinas, SP, Brasil Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP), Instituto de Ciência e Tecnologia de Sorocaba (ICTS), Departamento de Engenharia de Controle e Automação, Sorocaba, SP, Brasil FAPESP: 2011/15884-6 FAPESP: 2013/08545-6

This letter provides a comparison between the current and power injection models for angle and voltage stability analysis of power systems. Traditionally, it is believed that the current injection model is computationally more efficient. On the other hand, the power injection model requires computing the products of currents and voltages and, hence, is expected to be computationally more demanding than the current injection one. This letter compares the two approaches using a unique framework. The two formulations are compared through a dynamic 1479-bus model of the all-island Irish transmission system.