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The computation speed of computer systems is getting faster and the memory has been enhanced in performance and density through process scaling. However, due to the process scaling, DRAMs are recently suffering from numerous inherent faults. DRAM vendors suggest In-DRAM Error Correcting Code (IECC) to cope with the unreliable operation. However, the conventional IECC schemes have concerns about miscorrection and performance degradation. This paper proposes a pin-aligned In-DRAM ECC architecture using the expandability of a Reed-Solomon code (PAIR), that aligns ECC codewords with DQ pin lines (data passage of DRAM). PAIR is specialized in managing widely distributed inherent faults without the performance degradation, and its correction capability is sufficient to correct burst errors as well. The experimental results analyzed with the latest DRAM model show that the proposed architecture achieves up to 106 times higher reliability than XED with 14% performance improvement, and 10 times higher reliability than DUO with a similar performance, on average. [ABSTRACT FROM AUTHOR]

The convergence of edge computing and deep learning empowers endpoint hardwares or edge devices to perform inferences locally with the help of deep neural network (DNN) accelerator. This trend of edge intelligence invites new attack vectors, which are methodologically different from the well-known software oriented deep learning attacks like the input of adversarial examples. Current studies of threats on DNN hardware focus mainly on model parameters interpolation. Such kind of manipulation is not stealthy as it will leave non-erasable traces or create conspicuous output patterns. In this paper, we present and investigate an imperceptible misclassification attack on DNN hardware by introducing infrequent instantaneous glitches into the clock signal. Comparing with falsifying model parameters by permanent faults, corruption of targeted intermediate results of convolution layer(s) by disrupting associated computations intermittently leaves no trace. We demonstrated our attack on nine state-of-the-art ImageNet models running on Xilinx FPGA based deep learning accelerator. With no knowledge about the models, our attack can achieve over 98% misclassification on 8 out of 9 models with only 10% glitches launched into the computation clock cycles. Given the model details and inputs, all the test images applied to ResNet50 can be successfully misclassified with no more than 1.7% glitch injection. [ABSTRACT FROM AUTHOR]

The article describes the concept connected vehicle remote diagnostic system intended to increase the useful life of the vehicle and provide a simple interaction with the service center. In article the substantiation of mathematical model of communications in system of diagnostics of an electric equipment of cars in a kind, suitable for mathematical processing is resulted. It is offered to use model at which all making systems are represented in the form of structure of final automatic machines. By means of large-scale and large-capacity data exchange across multiple systems, connected car solution performs global traffic control on every connected vehicle and real-time traffic control on every connected road, thereby improving transportation efficiency and ensuring traffic safety. This future-oriented solution also provides predictive maintenance, advanced driver assistant system analysis, artificial intelligence (such as personal assistant), vehicle-road coordination services, and fault demarcation capabilities. Remote diagnostics allow service centers and emergency support to diagnose at a distance and to prepare for dealing with a vehicle that is in the path or in the service center. [ABSTRACT FROM AUTHOR]

The representation of analyzed data by complex network brings different views on the problem which could lead into the increase of the number of valuable features. The study described in this paper aims on the representation of the similarities of pulses from the classified signal into the complex network. The analysis of signals' pulses is purposed by correct classification of the signals measured on medium voltage (MV) overhead lines with application of covered conductors (CC). There is plenty of features available to extract from complex network, therefore they should be properly analyzed and evaluated according their relevancy. [ABSTRACT FROM AUTHOR]

This paper introduces a generalized reduced model of AC-DC-AC converters which enables techniques of model-based control design. A Proportional-Multi-Integral (PMI) observer for fault detection, isolation and reconstruction (FDIR) is proposed based on the previously introduced generalized model. It is shown that the model-based FDIR scheme is able to isolate and reconstruct sensor and actuator faults in AC-DC-AC converters. [ABSTRACT FROM AUTHOR]

This paper follows four main objectives. Firstly, to provide an overview of the latest and most demanding Fault Ride Through requirements from various international jurisdictions. Secondly, to support power system operators in understanding Fault Ride Through capabilities of modern wind turbines. Thirdly, an overview of state of the art validation of FRT is provided. Finally, to give an outlook of what additional functionalities will be available from wind turbines in the near to medium future. [ABSTRACT FROM AUTHOR]

With the increasing demand of super high scale of integration and small form factor in advanced semiconductor products, especially those that integrate DRAM and logic dies, 3D IC and Wafer-Level Chip-Scale Packaging (WLCSP) are considered promising approaches. In Integrated Fan-Out (InFO) WLCSP, a large number of fine-pitch pads, where neighboring pads cannot be probed simultaneously due to insufficient pitch, are used as the contact interfaces of inter-die interconnections. If the fine-pitch pads cannot be probed, the interconnections between the pads and boundary scan cells (BSCs) cannot be tested, which can lead to higher defect level. From industrial investigation, untested finepitch pads lead to 1-2% test coverage loss. To improve the overall test coverage, in this paper, we propose a pre-bond probing methodology for fine-pitch pads of InFO WLCSP. By the proposed probing schemes, open/short faults on the interconnects between the fine-pitch pads and BSCs can be all tested by the ATE. Moreover, for short faults that only occur between adjacent pads (interconnects), we propose a grouping method to determine the test patterns at each probing stage, which can minimize the test time. We also show that our method can achieve 100% test coverage of open/short faults. [ABSTRACT FROM AUTHOR]

In the discussions carried out in this paper, we acknowledge the main ideas and principles of distribution networks based on distributed generation (DG). We can see a growing trend of generation from renewable energy sources and automatically distributed occurrence for energy sources. Distributed energy sources are nodes that produce electric energy locally, to power consumers in the immediate vicinity. After fleshing DG nodes, it was found, that in some cases, groups of distributed generation units work alone, forming islands. These islands are areas of networks are energized before, during and after disconnecting the primary source of energy, but which continue to be fueled through the grid fault by the DG units. Consequently, worldwide, there have been made investments in research and development of solutions to protect electrical grids, if they succumb to different faults, by turning the protections of antiislanding, and disconnect generators from the power injection of PCC (Point of common coupling). In parallel with solving problems that grid islanding poses, there are also studies of achieving intentional islanded networks. These networks function in the form of Micro Grid sites, independent of the network or in parallel to the primary network feed. Although there are some advantages for supplying power in an islanded configuration, until now, projects that support the creation of Micro Grid are relatively few. Given the technical problems to be solved, in some communities, it's required to install anti-islanding protection, not being allowed to function as an island connected to RED. To address the issues raised by intentional islanding, we have developed methods for monitoring, operating and automatic interpretation of states. One of the technical solutions is Micro Grid Controller (MGC), researched, manufactured and implemented by ABB. It comes with solutions based on smart grid concept, which enables management of energy resources in the Micro Grid automatically using units installed at each generation. Knowing the theoretical details of implementing a system islanding with distributed generation, simulations have been done to assess the possibility of a network islanding. Based of the values extracted, a hypothesis was formed that shows the possibility of islanding, through simulation, of an entire grid. The simulation process imposed a theoretical and graphical study of the general hypothesis [2]. [ABSTRACT FROM AUTHOR]

The increasing risk of negative sequence phenomena during large-scale substitution of synchronous generators by converter-based generation has been widely discussed in recent years. Such negative sequence phenomena may be over-voltages in healthy phases and tripping of protection relays during asymmetrical faults. This has led to the introduction of requirements for asymmetric current injection into the new German high voltage grid code (VDEAR-N 4120). This guideline, which all new 110kV-connected power plants will have to fulfill from January 1st 2017, defines a negative sequence contribution in asymmetrical faults similar to the positive sequence current contribution during grid faults. In order to fulfill these requirements, a new inverter control strategy was developed by ENERCON, which brought about several performance enhancements, such as an improved accuracy of measurement and current control and high flexibility to meet a variety of grid requirements. As part of their mandatory certification, each Wind Energy Converter (WEC) model needs to undergo a comprehensive measurement and validation process that shall prove compliance with the given requirements. Measurements have recently been completed on the first WEC model. In this paper, test results will be presented to show the enhanced behavior during symmetrical and asymmetrical grid faults as well as further improvements of the new control system. [ABSTRACT FROM AUTHOR]

the rapidly increasing share of wind power in the electrical power system is both concerning and challenging for the system operators. This leads to stringent requirements for the connection and operation of Wind Power Plants (WPPs) and respectively Wind Turbines (WTs). Taking these and other challenges into account, the Siemens Wind Power (SWP) 3.X MW variable-speed direct-drive WT series or D3 platform (SWT-3.0 MW, SWT-3.2 MW and SWT-3.4 MW) employ direct-drive technology that reduces the components' wear and tear; thus improving performance, reliability and maintainability. Furthermore, for the very purpose of grid assessment and system studies, SWP has developed and provides dynamic electrical simulation models for the D3 platform in various power system simulation tools, such as DIgSILENT PowerFactory, Siemens PTI PSS®E, PSCAD, EMTP-RV and PSS®NETOMAC. The dynamic simulation models are validated against fault-ride through tests and other specific purpose measurements in order to ensure accurate model performance. This paper presents measurements and model validations of SWT-3.2 MW WT. Measurement results are scalable and the results and performance can be easily extended to other Wind Turbines of the D3 platform including SWT-3.0 MW and SWT-3.4 MW as they all share a common converter hardware and software core. The presented results as well as other benchmarking results show relatively good match between measured and simulated results. [ABSTRACT FROM AUTHOR]

The rapid expansion of wind power has led many transmission system operators (TSOs) to demand modern wind power plants (WPPs) to comply with strict grid interconnection requirements. Such requirements involve various aspects of wind power plant operation, including fault ride-through and power quality performance as well as the provision of ancillary services to enhance grid reliability. During recent years, the National Renewable Energy Laboratory (NREL) of the U.S. Department of Energy has developed a new, ground-breaking testing apparatus and methodology to test and demonstrate many existing and future advanced controls for wind power generation (and other renewable generation technologies) on the multi-MW scale and medium-voltage (MV) levels. This paper describes the capabilities and control features of NREL's 7-MVA power electronic grid simulator (also called a controllable grid interface, or CGI) that enables testing many active and reactive power control features of modern wind turbine generators-including inertial response, primary and secondary frequency responses, and voltage regulation under a controlled medium-voltage grid environment. In particular, this paper focuses on the specifics of testing the balanced and unbalanced fault ride-through characteristics of wind turbine generators under simulated strong and weak MV grid conditions. This paper also describes the test results for some advanced control features, such as wind generation's participation in power system oscillation damping. In addition, the paper provides insights on the power hardwarein-the-loop (PHIL) feature implemented in the CGI to emulate (in real time) the conditions that might exist in various types of power systems under normal operations and/or contingency scenarios. Using actual test examples and simulation results, this paper describes the value of CGI as an ultimate modeling validation tool for all types of "grid-friendly" controls by wind generation. [ABSTRACT FROM AUTHOR]

Previous work has shown that ultrasonic inspection provides a means of assessing electrical crimp quality that ensures the electrical and mechanical integrity of an initial crimp before the installation process is completed. The amplitude change of a compressional ultrasonic wave propagating at right angles to the wire axis and through the junction of a crimp termination was shown to correlate with the results of destructive pull tests, which is a standard for assessing crimp wire junction quality. Of additional concern are crimps made at high speed assembly lines for wiring harnesses, which are used for critical applications, such as in aircraft. During high-speed assembly it is possible that many faulty crimps go undetected until long after assembly, and fail in service. The position and speed of the crimping jaw become factors as the high-speed crimp is formed. The work presented in this paper is designed to cover the more difficult and more subtle area of high-speed crimps by taking into account the rate change of the measurements. Building on the previous work, we present an analysis methodology, based on transmitted ultrasonic energy and timing of the first received pulse that is shown to correlate to the gauge of the crimp/ferrule combination and the position of the crimping jaw. Results demonstrating the detectability of a number of the crimp failure pathologies, such as missing strands, partially inserted wires and incomplete crimp compression, are presented. The ability of this technique to estimate crimp height, a mechanical measure of crimp quality, is discussed. [ABSTRACT FROM AUTHOR]

In this paper electric studies considering an oil upstream facility with wind power and conventional generators are presented. Static power flows are performed. The voltage variations and reactive power requirements are analyzed. Also dynamic fault simulations, with and without the island formation are performed. The objective is to assess the impact of wind power generation to be included in a typical facility, in order to achieve a satisfactory performance. This work simulates a typical upstream facility, conformed by a 10.1 kV oil network a conventional motogenerator and different types of wind power plants. Wind turbine models and controls for electromechanical transients are used. [ABSTRACT FROM AUTHOR]

The predominant North-South active power flows across the border between Scotland and England are currently limited by stability considerations. As the penetration of variable-speed wind power plants in Great Britain grows, it is imperative that stability limits, operational flexibility, efficiency and system security are not unnecessarily eroded as a result. The study reported in this paper illustrates the impacts on critical fault clearing times and power transfer limits through this North-South corridor in the presence of increasing levels of wind power plants on the GB transmission system. By focussing on the behaviour of a representative reduced test system following a three-phase fault occurring on one of the two double-circuits of the B6 boundary, the impacts on transient stability margins are qualitatively identified. By altering the immediate post-fault active power recovery ramp-rate of the wind power plants, the transient stability performance of the grid with additional wind power can be significantly improved. The outputs of the project are intended to provide a basis for further detailed studies on a more realistic network model. [ABSTRACT FROM AUTHOR]

This article gives an overview of power system services provided by HVDC-connected wind power plants. With the help of a large set of references, the state-of-art in the field is discussed, with particular focus on VSC-based HVDC technology, and, where relevant, possible alternative solutions. This allows understanding where industry and academia stand as of today and trace the line for future work in the subject. Sample simulation results from the authors' own work are also used to elucidate some of the concepts. The following services are within scope: active power balance control, AC voltage control, power oscillation damping and fault-ridethrough. [ABSTRACT FROM AUTHOR]

A study of the integration of 1100 MW of offshore wind power in the Baltic Sea into the onshore transmission system of 50Hertz Transmission has revealed the risk of severe temporary overvoltages following electrical faults. The duration of the overvoltages could range between seconds and minutes, and significantly increase the risk of both offshore and onshore generation losses. It is proposed to mitigate the risks through improved high voltage ride-through capability of generation plants and the installation of a STATCOM in the onshore transmission system. [ABSTRACT FROM AUTHOR]

This paper presents a methodology for model-based fault detection and diagnosis underpinned by Modelica models and using a qualitative approach to diagnosis, which has been applied to diagnosis of an air handling unit based on data recorded by a building management system. The main steps from model development to component diagnosis are discussed and illustrated using a heating coil component. [ABSTRACT FROM AUTHOR]

Frequency stability is one of the most crucial aspects of large transmission power systems. Until now the conventional power plants have ensured that the frequency is maintained within the permissible band. This paper deals with the Fully Rated Converter (FRC) wind generators since they do not contribute to the power system's inertia and constitute one of the most common used concept to boost wind power penetration. The theoretical FRC and both the original Enercon model and the PowerFactory Template will be used to analyze the dynamic behavior in case of faults using a Test System implemented in DigSILENT PowerFactory Simulation Software. The different dynamic response between the models demonstrates the appropriateness of each one regarding the faults and the network model in question. [ABSTRACT FROM AUTHOR]

The European Transmission System Operators specify grid codes to ensure a safe and reliable operation of the electrical power system. Wind Power Plants have to comply with specific requirements prior installation and operation but some of the requirements are open to interpretation due to a lack of specificity. This paper focuses on the rise time requirement specified in European grid codes where different interpretations leave an open debate whether the requirement can be fulfilled or not. The definitions present in European grid codes are evaluated in this paper with the following methodology: first the uncertainties in some Transmission System Operators' definitions of rise time, step response time and settling time are presented; then a comparative analysis is performed among calculation methods, such as instantaneous reactive current in alpha-beta reference frame, direct and quadrature reference frame, and Root Mean Square of the positive sequence component. All the calculations are first performed on an ideal data test case, and thereafter on a real site data test case. Finally, the reactive current rise time is computed from all test cases with all calculation methods, and the rise times computed with different methods are then compared. The comparison shows that the rise time of the reactive current is significantly affected by the calculation methods: this effect in some cases can make the difference between fulfilling the requirement or not. As a result of that, both manufacturers and Transmission System Operators can draw different conclusions about a turbine's compliancy with the grid code. [ABSTRACT FROM AUTHOR]

In converter-dominated grid structures, the converter controls and non-linearities of the converters dominate the behaviour of the system including the overall system stability. Especially in grids with no conventional generators, where a group of converters has to define the grid voltage, an adequate converter control is essential and, therefore, has to be assessed in a very early project phase. Within this paper, the modelling approach for power-electronic systems including control algorithms is presented. The typical structure of the control algorithms and its interaction with simulations in period domain is described briefly, where period domain denotes a type of analysis suitable for systems including DFT or FFT in their control path. Furthermore, a new solving approach for steady-state period-based systems is introduced. The capability of the approach is demonstrated using simulation results of a converter-dominated offshore-wind farm challenged by a representative unsymmetrical fault scenario. [ABSTRACT FROM AUTHOR]

In the recent grid codes, wind power plants are required to stay connected and inject reactive and active currents during grid short-circuit faults, even when the grid voltage drops down to zero. However, the physical fact, Loss of Synchronism (LOS) of wind turbines during these very low voltage faults has been underestimated in the grid codes; and the LOS has recently been explored only in few studies. In this paper the LOS phenomenon is studied, especially focusing on the case of a string of wind turbines, rather than an aggregated one. It is shown that the LOS affects the wind power plant as whole. Additionally, existing methods to solve the LOS problem are briefly reviewed, and a closed loop frequency based solution is implemented within PowerFactory simulations of a detailed generic wind power plant model. [ABSTRACT FROM AUTHOR]

This paper concerns with the fault analysis and the protection design for offshore wind farms with a series-dc collection system and a voltage source converter (VSC) based HVDC transmission to the onshore grid. Different fault conditions are identified and the system behavior during these faults is discussed. Threats to post-fault operation of the system and its components that each fault condition implicates are presented along with the protection requirements. Measures to mitigate these threats and to reduce the speed requirement of breakers are proposed. To quantify the protection needs, detailed fault analysis is presented for a wind farm with the most obvious grounding scheme and the cable layout using numerical simulations. It is found that, for faults in the sending network, tripping of the healthy terminals due to overcurrent and instability during fault are major concerns for the postfault system operation. On the other hand, transmission line faults make the system operation impossible. Nonetheless, a transmission line fault still needs to be isolated to protect the terminal diodes from large freewheeling currents. Effects of cable layout and the grounding scheme on the system fault behavior are discussed. [ABSTRACT FROM AUTHOR]

This paper analyzes effects of squirrel cage faults on submersible induction motors efficiency at steady-state condition. There are a lot of studies about effects of the cage faults on motor performance. Especially, the effects of the cage faults on the motor parameters such as current, torque and speed are well known. Unlike the literature, cage fault effects on efficiency are analyzed in this study. Furthermore, fluctuations and mean value changes resulting from the rotor faults are ranked according to size of these faults. Healthy and five different faults were investigated by using 10 HP, 25 HP, 30 HP and 50 HP submersible induction motors in both simulations and experiments. Time stepping finite element method solution was used to compute motor quantities in the simulation. Good agreement was achieved between simulation and experimental results. The effects of rotor faults on motor efficiency were clearly ranked according to size of faults. [ABSTRACT FROM AUTHOR]

Semiconductor technology evolution enables the design of resource-constrained battery-powered ultra-low-cost chips required for new market segments such as environment, urban life and body monitoring. Caches have been shown to be the main energy and area consumer in those chips. This paper proposes simple, hybrid-operation (high Vcc, ultra-low Vcc), single-Vcc domain Adaptive Performance-Predictable Low-Energy (APPLE) L1 cache designs based on replacing energy-hungry SRAM cells by more energy-efficient and smaller cells enhanced with extra cache lines set up in an adapted victim cache to still enable strong performance guarantees. APPLE caches are proven to largely outperform existing solutions in terms of energy and area efficiency. [ABSTRACT FROM AUTHOR]

By allowing the occurrence of infrequent timing errors and correcting them online, circuit-level timing speculation is one of the most promising variation-tolerant design techniques. How to effectively test timing-speculative circuits, however, has not been addressed in the literature. This is a challenging problem because conventional scan techniques cannot provide sufficient controllability and observability for such circuits. In this paper, we propose novel techniques to achieve high fault coverage for timing-speculative circuits without incurring high design-for-testability cost. Experimental results on various benchmark circuits demonstrate the effectiveness of the proposed solution. [ABSTRACT FROM AUTHOR]

The Fault level determination through fault level studies is a basic requirement for the connection of any generation or load to the electrical network. Thereby, the standard IEC 60909 is internationally either directly used or referred to. The developed methods presented within the standard have not undergone major revision and are based upon traditional synchronous machine dominated networks. While other types of generators are discussed and an attempt is made to improve their representation through updates of the standard, there is currently no accurate representation of wind turbines with doubly fed induction generators (DFIG). These 'unconventional' machine types have fault characteristics dominated by power electronic control system operation rather than rotating machine principles. While suitable for representing upstream network faults, the existing IEC 60909 fault current representation becomes less accurate the closer the fault occurs to the wind turbine itself. The fault contribution of Wind turbines with DFIG generators is often overestimated, contributing to over specification of HV-equipment and erroneous grading of protection equipment. As such, recognizing the influence of the controlled fault in-feed from wind turbines is important for static fault level studies based on IEC 60909 which are commonly performed for protection designs. Specifically the initial symmetrical short circuit current, symmetrical short circuit breaking current and the short circuit impedance are of interest. This paper discusses the difficulties experienced with existing approaches for representing fault current in-feed when applied to wind turbines equipped with DFIG generators. Further, the paper proposes a new method to achieve meaningful values and results when performing IEC 60909 studies for this generator type. [ABSTRACT FROM AUTHOR]