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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.

DC power flow controller (PFC)s are suitable equipment to provide secure/reliable operation of the multiterminal HVDC (MT-HVDC) networks. Also, they enhance the controllability of these grids. This paper proposes a new representation of the Newton-Raphson (NR) based DC power flow (PF) solver to provide suitable DC PF studies of PFC compensated/flexible MT-HVDC grids. To achieve this aim, the power injection model (PIM) (under static condition) for an interline DC PFC (IDC-PFC) is proposed and embedded within the presented DC PF solver (DC-PFS) while the symmetry and original framework of the conductance matrix of the system is yet preserved and the proposed concept imposes a few changes on the related Jacobin matrix. In the proposed model, resistive shunt admittance of HVDC lines is also taken into account. Modifying the physical and control state variables of the whole system (IDC-PFC and MT-HVDC grid) in a common collaboration, the predetermined control objective(s) are obtained. The accurate concept and effectiveness of the presented IDC-PFC models and new representation of the NR-based DC-PFS are verified by performing dynamic and static simulations on an 8-bus MT-HVDC test network.

The IC stripline, an IEC radiated electromagnetic susceptibility (EMS) method, is utilized for evaluating the injection pulling and locking effects of the voltage-controlled oscillator (VCO). An IC stripline with the bandwidth of 2.5 GHz is realized and the test setup is built. A commercial VCO is tested for demonstration. Another IEC conducted EMS test, direct power injection, is also performed for comparison. The results show the effectiveness of characterizing injection pulling and locking of VCO by using the proposed solution.

The CAN controller with silicon on insulator (SOI) CMOS technology is designed to compare the electromagnetic compatibility (EMC) characteristics between SOI and SI technologies. The immunity test bench and the conducted emission test bench are built following direct power injection (DPI) method and 150 Ω method. The test results show that the chip with SOI technology has better immunity; the chip with SI technology has lower emission level.

This paper presents verification and implementation of two three-phase four-wire $(3\Phi 4\mathrm{W})$ 350 kVA multi-function converters. In the paper, direct digital control laws for achieving multiple functions, including power injection, rectification, active power filtering (APF), and three-phase power balancing, are presented and derived in detail. Because of the limitations of test-equipment and components, this study conducts circulating power test. Experimental and simulated results from two 350 kVA multifunction converters are used to verify the analyses, designs and discussions.

This paper proposes a multi-objective preventative-emergency coordinated control (MO-PECC) method for high wind-penetrated power systems. The method facilitates utility-grade energy storage (ES) to realize post-contingency emergency control, and can generate indicator of system instability risk for solution sets. Once an unstable post-contingency system is detected, the ES systems immediately react for power injection/retraction, thus achieving emergency control to alleviate short-term system power imbalance and stabilizing the system together with synchronous generators. Numerical tests are performed on a modified IEEE-39 system, in which 3 synchronous generators are replaced by 3 same-scale wind farms. The test results verified the effectiveness of the proposed coordinated method, and the calculating time is relatively small, which is suitable for online calculation.

This paper presents two models of AC optimal power flow based Financial Transmission Rights (FTRs) allocation auction. Both models were compared with the conventional DC optimal power flow (DC-OPF) based model. Considering an FTR between two nodes as a real power injection at the source node and a power withdrawal at the sink node; the first model assumes that the net power due to FTRs equals zero. FTRs do not consider loss and the slack node is compensating for the total system losses. In the second model, it is suggested that each FTR's source node is taking care of a portion of the system loss by introducing a power injection. The portion of loss compensation is proportional to each FTR allocated amount, i.e., if one FTR is to use the grid more, then it should compensate more for the loss. To show the validity of all models and the advantages of the new suggested model, numerical examples of a 3-bus system and the IEEE 14-bus system are presented. All results are compared and explained.

The existence of new power injection at a system will effect system stability that existed before, so stability analyze was needed to know the system conditioning before and after power injection, and performance system after disturbance, by observe rotor angle, frequency, and voltage. The result of dynamic system show that power injection of Gen XY can supply 0,021 pu at bus 1, 0,001 at bus 2, 0,001 at bus 3, 0,0261 pu at bus 4, 0,0366 pu at bus 5, 0,0186 pu at bus 6, 0,0101 pu at bus 7, 0,0083 pu at bus 8, 0,0061 pu at bus 9. When 3 phase fault during 1–2 second happened, the frequency and rotor angle increasing. When generator XY inject system with 50 MW, the modified IEEE 3 Generator 9 Bus become increase with frequency 60.27 Hz, voltage profile increasing, rotor angle decreased close to normal conditions.

This paper introduces two circuit-level reactive sensor-based countermeasures against malicious implementation attacks exploiting EM-radio leakage from and injection to cryptographic processors. An LC-oscillator-based sensor detects a tiny micro-EM probe approaching proximity to the processor for a passive EM analysis attack. A PLL-based sensor detects intentional high-level EM power injection for an active EM fault injection attack. Hardware-level security enhancement of the crypto processor has been demonstrated with successful sensor operations silicon-proven by ASIC and FPGA test-chip measurements.

This proposal presents a 0.55V and low power divided-by-2 injection-locked frequency divider (ILFD) using native nMOS as the injection MOSFET with threshold voltage nearly equal to zero. The measured locking range is 6.1 to 7.45 GHz at injection power of 0dBm. Excluding output buffers, the ILFD consumes the power 0.69 mW under a standard supply of 0.55 V for biomedical application.

The change towards future distribution networks requires new and updated monitoring and control functions, which involve a large amount of information. The treatment of a significant part of this information can be simplified by introducing the concept of Load Area, a group of prosumers whose power injection has a similar impact on the distribution grid operating conditions. Thanks to the Load Area concept, a compact yet accurate representation of distribution networks can be obtained. The Load Areas allow to select the relevant data for both monitoring and control functionalities of distribution systems, as well as to represent the relationships between such data in a compact representation. In this paper, the Load Area concept is recalled, and specialized methods are applied to get a compact representation that exploit the radiality. The results from two test cases confirm the viability of the proposed methods and highlight the computational gains deriving from their adoption.

In this paper, we propose a secure and privacy-preserving communication scheme for power injection for the smart grid storage units. The idea is based on collecting masked bids from storage units at an aggregator and send aggregated bids to the utility rather than the individual ones. The utility company can ensure the integrity and authenticity of the aggregated bid without accessing the individual bids. In this way, no party will have access to the storage units' data and make use of it to achieve unfair financial gains. Our evaluations have demonstrated that the proposed scheme is secure and can achieve the privacy requirements. Moreover, the scheme requires acceptable communication and computation overhead.

This paper introduces a new Direct Power Injection (DPI) set-up used to characterize the conducted immunity of integrated circuits (IC) with differential inputs. It allows injecting common-mode, differential-mode signals or any combination of both. For a given kind of injection, it is necessary to calculate power and phase-shift at generators. To do so, an analytic model is developed based on S-parameters of all blocks involved in the set-up including the IC. This model is validated by simulation under PSpice and by measurement in [1 MHz – 800 MHz] band for pure common-mode and pure differential-mode injections. With this set-up, IC immunity can be characterized as functions of common-mode and differential-mode voltages versus frequency.

This paper presents a study about temperature effect on the conducted susceptibility level of a microcontroller. Based on direct power injection, the electromagnetic susceptibility of microcontroller is measured under different temperatures. Measurement results show that different temperature conditions could result in fluctuations of conducted susceptibility level. To analyze the temperature effect on susceptibility level, several potential threats in passive part, microcontroller input/output buffer and clock signal are presented in this paper.

In this paper we examine different scalar vulnerability metrics that account for system topology and power injection profile. We pose calculable metrics related to the ratio of power disrupted along a cutset to the number of lines on a cutset. It is intended that the metrics can be used to assess the system's susceptibility to large disturbances.

This paper deals with direct power injection (DPI) simulations and it focuses on the simulation framework and post processing strategies to be performed during the design phase of automotive integrated circuits (ICs). The aim of such susceptibility simulations is to assist a designer to predict the ICs susceptibility to radio frequency interferences (RFI) during the design phase of the IC. For this purpose a complete DPI simulation model according to the standardized DPI measurement setup is introduced. Based on a simple example the methodology and several DPI simulation results are shown together with possible post processing strategies.

The electromagnetic compatibility (EMC) performance of the voltage regulators is the significant factor in the EMC performance of the complete electronic system. In this paper the characterization of the voltage regulator by direct power injection (DPI) method is presented. Although, the DPI method is defined by various standards, the repeatability of the measurement can be compromised by several factors. The DPI method measurement results are presented for the L4949 voltage regulator. The repeatability of the method is assessed by various factors related to the operating point of the voltage regulator and to the measurement set-up. The obtained results are compared to the results presented by other authors.

The updated and new monitoring and control functionalities for distribution systems make available a huge amount of information. Indeed, not all the available information is needed to be considered; a significant simplification could be achieved by selecting and treating only the relevant information. With this aim, the concept of Load Area (LA) was recently introduced: a LA is a group of prosumers whose power injection has a similar impact on the distribution grid operating conditions. In the paper, the concept of LA is adopted to select the relevant data needed for the monitoring and control of distribution systems; a possible compact equivalent representation of the relationships between those data is proposed. The results from two test cases confirm the viability of the proposed modeling and highlight a relevant reduction in the amount of information used to describe the network.

The susceptibility to Electromagnetic Interference (EMI) of Battery Management Systems (BMSs) for Li-ion and LiPo battery packs employed in emerging electric and hybrid electric vehicles is investigated in this paper. To this purpose, a specif c test board is developed to experimentally assess the EMI susceptibility of a BMS front-end integrated circuit by direct power injection (DPI) and radiated susceptibility measurements. Experimental results are discussed highlighting different EMI-induced failure mechanisms observed during the tests.

Phasor Measurement Units (PMUs) are being employed in power system to achieve better monitoring and control of power grid. Due to their high cost, PMUs are placed at some strategic locations. However, while upgrading a power system monitoring structure, engineers may face problem of no communication facility at a bus. PMUs need a sound communication structure so that it can perform time-synchronized measurements by communicating with the GPS Satellites. This paper presents an optimal placement algorithm of Phasor Measurement Units (PMU) placement approach in a system where communication facility is limited. IEEE 14 bus system was selected and existing optimal PMU placement algorithms are modified considering the presence of power flow and power injection measurements.

Re-supplying loads on outage through cross-connect from adjacent feeders in a distribution system may cause voltage drop and hence require load shedding. However, the surplus PV generated in some of the LV feeders can prevent load shedding, and improve reliability. In order to measure these effects, this paper proposes the application of Direct Load Flow method[1] in reliability evaluation of distribution systems with PV units. As part of this study, seasonal impacts on load consumption together with surplus PV output power injection to higher voltage networks are also considered. New indices are proposed to measure yearly expected energy export, from LV to MV and from MV to higher voltage network.

Dispersed photovoltaic generation integrated in the low voltage distribution grids leads their operation towards an active approach. In that context, new methodologies are needed in order to identify and to accurately quantify the impact of this massive renewable penetration on the grid operation. For this purpose, the authors of this study have developed in a previous analysis a probabilistic load flow tool directly based on the use of smart meters data. The goal of this tool was to quantify probabilities of overvoltage in radial low voltage grids with increased photovoltaic penetrations. However, the drawback of this approach was the too long (15 minutes) sampling time step of smart meters that did not allow the consideration of fast fluctuations of photovoltaic generation. In the present paper, an original adaptation of the existing tool is therefore presented, which enables the consideration of short temporary photovoltaic power fluctuations. Thanks to this new development, it is shown that a more accurate estimation of overvoltage situations, due to photovoltaic generation, is permitted.

The latest development of Convertible Static Compensators (CSC) drives the importance of the Flexible AC Transmission System controllers to higher levels because of their controllable nature and effective power flow management of multi-line systems. To realize the effect of CSC on a given power system Interline Power Flow Controller (IPFC) is considered and Power Injection Model (PIM) for the same device is proposed in this paper. The comfort in mathematical modeling and the incorporation procedure in Newton-Raphson load flow with PIM increase its importance. In this paper, proper location to install device using contingency analysis is discussed. Numerical results without and with IPFC for the variation of device control parameters is presented. The obtained results show the performance of the proposed IPFC model.

The increasing penetration of Distributed Generation (DG) in distribution electrical systems may cause alteration of voltage profiles on the lines. Traditionally, distribution networks with radial configuration are designed as a passive top-down architecture where voltage regulation is mainly performed by an On-Load Tap Changer (OLTC) transformer located at the Primary Substation. Therefore it becomes rather difficult to compensate lines radiating out from the same bus-bar where some of these are subject to overvoltages due to the power injection by DGs connected whereas others are subject to voltage drops due to the presence of passive loads only. A first step in regulation and managing the voltage levels, in order to be consistent with the contingent needs of the network, may be a decentralized local control strategy performed by the DG units, however better results will be obtained with a coordinated OLTC intervention. In this paper an OLTC control strategy, based on only few remote measurements, is proposed. This procedure allows the tap changer controller to infer the state of network node voltages and to act accordingly. The performance of the proposed control method is demonstrated through simulations on a realistic MV distribution network.

In this paper, method to identify strong nodes in a transmission grid is shown. The method can be used to identify transmission system investment needs and can serve as filter for transmission system investment optimization. Based on an optimal power flow calculation, the maximum power injection capability of buses is calculated. In this context AC OPF and DC OPF methods are compared in terms of accuracy, convergence and computational effort. To take uncertainties in generation and load into account, the Gaussian Component Combination Method (GCCM) is used, which is compared to Monte Carlo Simulation (MCS). The importance of considering security aspects while determining strong nodes is depicted using N-1 analysis. Additionally, the effect of power flow controlling devices on the maximum power injection capability of investigated grid nodes is shown, in particular with phase shifting transformers and HVDC links.

In order to build an accurate impedance model, we provide a parameter determination method by using an artificial intelligence algorithm—acceleration particle swarm optimization (APSO). Comparing with the impedance model that is provided by IC-EMC 2.5, our impedance result is more close to the measurement result. The parameter determination of impedance model is validated by applying to the direct power injection (DPI) coupling path model.

Low frequency inter-area oscillations have been identified as a significant problem in utility systems due to the potential for system damage and the resulting restrictions on power transmission over select lines. Previous research has identified real power injection by energy storage based damping control nodes as a promising approach to mitigate inter-area oscillations. In this paper, a candidate energy storage system based on UltraCapacitor technology is evaluated for damping control applications in the Western Electric Coordinating Council (WECC), and an analytical method for ensuring proper stability margins is also presented for inclusion in a future supervisory control algorithm. Dynamic simulations of the WECC were performed to validate the expected system performance. Finally, the Nyquist stability criteria was employed to derive safe operating regions in the gain, time delay space for a simple two-area system to provide guaranteed margins of stability.

This paper presents results of target location specific direct injection on a 8051-based microcontroller in a development board versus a custom test board. Three target locations showed no failure in both environments. Using the custom board, an effect was found in a target location which was not observed using the development board.

DPI (Direct Power Injection) testing according to IEC 62132-4 has been widely adopted as an effective test method for IC-level pin-selective RF immunity testing. To enable DPI testing of an IC, a dedicated test board needs to be designed that basically makes up the whole EMC test set-up. Boards that are designed in accordance with IEC 62132-4, should work well up to 1 GHz. However, various anomalies can occur if no proper care is taken of all possible RF phenomena. This paper explains our design approach to effectively deal with these issues and at the same time even extend the useful frequency range up to 2 GHz. Specific guidelines to achieve this objective are given.

Accurate prediction of the response of integrated circuit (IC) to electromagnetic interferences (EMI) is increasingly important. In this paper, a precise integrated circuit immunity model (ICIM) of electrostatic discharge (ESD) protection pads is developed and validated. The model consists of a parasitic RC network model and an ESD snapback model. The parameters of the physically-based parasitic RC network model are extracted from specifically designed structures with ESD pads and validated by S-parameter measurement data. The combined model is able to predict the immunity level more precisely and better support the immunity simulation of circuit under direct power injection (DPI) test.

In particular applications, integrated circuits (ICs) have to be designed to guarantee safe operations during severe electromagnetic aggressions stresses such as Direct Power Injection (DPI). Unfortunately, the simulation of functional failures during DPI events remains very challenging for analogue products due the large frequency domain and to the lack of models for internal parasitic coupling. This paper describes a test method to identify the design functions and the physical mechanisms that lead to functional failures when integrated circuits are submitted to EMC stress.

Parameter validation is a required task in power systems in order to improve the confidence of the simulation models. This paper shows the hybrid simulation as a smart method to perform the validation task. Available methods are discussed and a new one is proposed. The forced power injection method proposed is tested using virtual data recordings. Real PMU recordings from the Colombian System are used in hybrid simulations, showing large differences in the simulation models. It is suggested the need for developing smart tools for model and parameter assessment.

Based on additional nodal power injection method, this paper presents nodal power injection model of UPFC for three phase power flow calculation. Based on this model, use decoupling-compensation theory to calculate three phases power flow. Finally, the rationality and effectiveness of three phase load flow with UPFC is verified by the simulation. And the results reflect the effect of UPFC for improving the non-symmetry of three-phase flow.

Available Transfer Capability (ATC) is an operating index that plays an important role in guiding intra-area electricity trade for interconnected systems. Continuation power flow (CPF) is the main calculation approach used to determine ATC. But in the conventional CPF method, a specific proportional linear nodal power injection mode is widely adopted, accordingly, ATC achieved by this kind of the CPF approach is a specific value corresponding to certain an operation state, but not a reliable and economic ATC from the viewpoint of practical operation. In this paper, we focus on the selection of nodal power injection mode for ATC determination, and making comparison studies for different nodal power injection modes. Modal analysis is used to search for a load increase mode that mostly affect ATC, economic dispatch (ED) is incorporated into the CPF in a piecewise linear way. A master-slave iterative CPF method is proposed to calculate ATC. The IEEE-30 bus test system is used to testify the proposed approach, the simulation results show that the proposed approach can provide a more reliable and economic ATC.

The paper proposes a novel multi-area state estimator based on wide area measurements where only boundary buses are considered in the coordination level. The power injection measurements are not used during the coordination level reducing the number of states and therefore size of the problem. Instead, a set of pseudo-measurements are included whenever a power injection measurement is available in boundary buses. The proposed method was validated using the IEEE 300 bus system split into 7 different areas.

Susceptibility of radio frequency (RF) circuits against environmental noises was evaluated by way of direct power injection. Measurements performed on a 90-nm 2.45 GHz CMOS RF driver amplifier show that the injection of RF power into on-die p+ guard bands creates tones at the primary and up-converted frequencies. Simulation achieves the error of less than 2dB against the measured susceptibility of −40dB, with the models of passive impedance networks covering probing tips, die pads, metal wirings, as well as a silicon substrate.

This paper introduces complete simulation models of typical electromagnetic immunity tests for integrated circuits (ICs). Direct Power Injection (DPI), Near-field (NF) and Very- Fast Transmission Line Pulsing (VF-TLP) experiments are modeled accurately, and comparisons between simulations and measurements for each set-up demonstrate the validity of this approach and lead to the development of an immunity prediction method for ICs.

The purpose of this paper is to present a practical method for parallel operation of two or more UPS supplying an isolated load. The paper describes the mathematics and the implementation of the method. The control calculation delay have been thoroughly included within the method derivation. The method is further discussed to independent parallel operation of the UPS.

In this paper, focus is on the UPFC steady-state modeling for the implementation of the device in the Newton-Raphson load flow algorithm. Two models, deriving from the known voltage source model (VSM), are presented and analyzed in detail. One is a power injection model (PIM) and the other one is the new shunt admittance model (SAM). Each one of these models represents a more robust and feasible alternative to the VSM because it bypasses the difficulties arising from the VSM, maintaining its advantages, though. Different simulations are presented in the paper to test and compare the models: Newton's quadratic convergence of the load flow algorithm is guaranteed by implementing the PIM and the SAM, with high convergence speeds.

Corresponding to the increasing capacity utilization of power systems, a systematic use of the load-flow controlling capabilities of multifunctional FACTS devices can increase the available transfer capability (ATC) enabling additionally demanded power transits. For an effective power transit control, the aptitude of possible locations of FACTS devices is assessed by a sensitivity analysis based on the generation shift distribution factors (GSDF) and the power injection model (PIM). "Active lines" are introduced enabling a simplified examination without modifying the power system model. With these analysis methods, superimposed power transits can be evaluated regarding their feasibility and necessary installation of load-flow controllers (LFC) under consideration of contingency cases. A method for the determination of the ATC for a certain number of LFC is also presented. Finally an example of a computer-aided determination of favorable LFC locations for enhancing the ATC in extended power systems is discussed.