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Multiwavelets possess better properties than traditional wavelets. Multiwavelet packet transformation has more high-frequency information. Spectral entropy can be applied as an analysis index to the complexity or uncertainty of a signal. This paper tries to define four multiwavelet packet entropies to extract the features of different transmission line faults, and uses a radial basis function (RBF) neural network to recognize and classify 10 fault types of power transmission lines. First, the preprocessing and postprocessing problems of multiwavelets are presented. Shannon entropy and Tsallis entropy are introduced, and their difference is discussed. Second, multiwavelet packet energy entropy, time entropy, Shannon singular entropy, and Tsallis singular entropy are defined as the feature extraction methods of transmission line fault signals. Third, the plan of transmission line fault recognition using multiwavelet packet entropies and an RBF neural network is proposed. Finally, the experimental results show that the plan with the four multiwavelet packet energy entropies defined in this paper achieves better performance in fault recognition. The performance with SA4 (symmetric antisymmetric) multiwavelet packet Tsallis singular entropy is the best among the combinations of different multiwavelet packets and the four multiwavelet packet entropies. [ABSTRACT FROM PUBLISHER]

We propose in this paper a novel configurable multi-power-rail pad that combines power supply support circuits and a digital input/output (I/O) buffers designed for a wafer-scale system. This wafer-scale platform includes a reconfigurable wafer-scale circuit, the WaferIC, comprising an alignment-insensitive surface that can be configured to interconnect any digital components manually deposited on its surface. The proposed multi-power-rail pad minimizes power losses and heat dissipation within the circuit. The pad that is fed from two distinct voltage sources providing power at 1.8 and 3.3 V has been implemented and tested. This pad has two merged configurable control loops that can select the power source. Merging takes place through shared transistors. This dual supply pad embeds a voltage regulator that achieves a fast response time of 21.1 ns and that can operate over a wide range of configurable regulated output voltage, from 500 mV up to 2.955 V. This regulator is capable of providing a maximum output current of 40 mA while needing only a very small quiescent current of 126 \muA. The regulator's power supply noise rejection ranges from -25 down to -40 dB for frequencies ranging from 1 kHz up to 1 MHz. The embedded digital I/O pad shares a common output with the power distribution and can be configured from 0.5 up to 3.3 V for a maximum speed of 250 MHz. [ABSTRACT FROM PUBLISHER]

It is known that any scalar function f(p) of the complex frequency variable p that is the admittance function of a passive finite network is in fact the admittance function of a network that can be realized without transformers. This paper shows that an m x m matrix-valued function Y(p), m ≥ 2, given that it is an admittance matrix, is the admittance of a network that contains no transformers if and only if it enjoys two further properties: 1) for each real p > 0 Y(p) is the admittance of a passive resistive network specific to p; and 2) a property defined as the null space property. It is shown that property 1) severely limits the class of m-terminal networks, m > 1, that can be realized without transformers. The author concludes that, for passive systems, transformers are here to stay. [ABSTRACT FROM AUTHOR]

Research on the smart grid is being given enormous supports worldwide due to its great significance in solving environmental and energy crises. Electric vehicles (EVs), which are powered by clean energy, are adopted increasingly year by year. It is predictable that the huge charge load caused by high EV penetration will have a considerable impact on the reliability of the smart grid. Therefore, fair energy scheduling for EV charge and discharge is proposed in this paper. By using the vehicle-to-grid technology, the scheduler controls the electricity loads of EVs considering fairness in the residential distribution network. We propose contribution-based fairness, in which EVs with high contributions have high priorities to obtain charge energy. The contribution value is defined by both the charge/discharge energy and the timing of the action. EVs can achieve higher contribution values when discharging during the load peak hours. However, charging during this time will decrease the contribution values seriously. We formulate the fair energy scheduling problem as an infinite-horizon Markov decision process. The methodology of adaptive dynamic programming is employed to maximize the long-term fairness by processing online network training. The numerical results illustrate that the proposed EV energy scheduling is able to mitigate and flatten the peak load in the distribution network. Furthermore, contribution-based fairness achieves a fast recovery of EV batteries that have deeply discharged and guarantee fairness in the full charge time of all EVs. [ABSTRACT FROM PUBLISHER]

We study battery filling policies with hard deadlines when the supply of energy can be modulated. This occurs for example with an electric plug-in vehicle using an adjustable electricity service for charging; such a service is offered in some countries as a means to provide flexibility to operators, and typically involves non-scheduled service reductions combined with a service guarantee that constrains these reductions. The problem for the battery user is to determine a charging policy, which we call a “consumption policy,” that meets a given “full battery” deadline while minimizing the energy cost (i.e., the bill paid to the electricity provider). As the charging efficiency is diminishing with respect to consumption, it is not optimal to charge as much and as early as possible. On the other hand service reductions cannot be predicted but it is possible to gain some information on the worst case reduction by analyzing past reductions. In this context, the computation of a causal consumption policy is an open problem. In this paper we consider a battery user interested in charging her battery while minimizing the worst case cost, where the total cost is a sum of two terms that reflect ( i) the total energy consumption and ( ii) the distance to a full battery at the deadline. We prove that there exists a causal consumption policy that minimizes the worst-case cost of the user. We find that the policy is threshold-based and give an efficient method to explicitly compute it at any time based solely on knowledge of past reductions, of the service guarantees and on the current distance to completion. Our method is based on the use of service curves and game theory. [ABSTRACT FROM PUBLISHER]

This paper describes a time-limited power distribution control technique that can be used for single-inductor multiple-output (SIMO) DC–DC converter with many unbalanced loads. Furthermore, the true all-comparator control technique that raises no stability or complexity issues is proposed. This all-comparator technique for SIMO converters is realized only with a single shared hysteresis comparator at a constant switching frequency of 800 kHz. This leads to the development of a new inductor peak-current control technique that does not require compensators and a phase-locked loop. This converter is analyzed and compared with existing SIMO converters with respect to the requirements of next-generation power management ICs. The maximum efficiency of the converter reaches 92%. The fabricated chip supporting eight-channel outputs is implemented in a 0.35-\mu\ m CMOS process and occupies an area of 2.4\times 2.1\ \ mm^2. [ABSTRACT FROM PUBLISHER]

In this paper, a bus design scheme that achieves both impedance matching and uniform power distribution for a multidrop bus is presented. In contrast to conventional schemes, the proposed scheme lets the line impedance of each segment of the bus vary, and the impedance-matching resistance values are determined accordingly, thereby providing higher degrees of freedom for optimization. General formulas for determining the optimal line impedances and matching resistances are derived. The voltage and power ratios between the master driver and branch receivers are also established, showing that such ratios depend only on the master-to-branch impedance ratio and the number of branches. Similar relations are also derived for the backward direction. The measurement results of the fabricated FR4 printed circuit boards demonstrate good agreement with the theoretical results, and show reliable performance up to a bit rate of 5 Gbps. [ABSTRACT FROM PUBLISHER]

This paper deals with the design of single-stage differential low-noise amplifiers for ultra-wideband (UWB) applications, comparing state-of-the-art planar bulk and silicon-on-insulator (SOI) FinFET CMOS technologies featuring 45-nm gate length. To ensure a broadband input impedance matching, the gm-boosted topology has been chosen. Furthermore, the amplifiers have been designed to work over the whole UWB band (3.1-10.6 GHz), while driving a capacitive load, which is a realistic assumption for direct conversion receivers where the amplifier directly drives a mixer. The simulations (based on compact models obtained from preliminary measurements) highlight that, at the present stage of the technology development, the planar version of the circuit appears to outperform the FinFET one. The main reason is the superior cutoff frequency of planar devices in the inversion region, which allows the achievement of noise figure and voltage gain comparable to the FinFET counterpart, with a smaller power consumption. [ABSTRACT FROM AUTHOR]

Abstract-Ensuring the integrity of the power supply in the power distribution networks (PDNs) of a chip is essential for building reliable high-performance chips. To ensure the power integrity, accurate, and memory-and time-efficient simulation approaches for simulating the power-supply noise in the on-chip PDN are essential. In this paper, a finite-difference formulation based on the latency insertion method (LIM) has been employed for simulating the power-supply noise in the on-chip PDN. A new common-mode type equivalent circuit has been proposed. In this equivalent circuit, a capacitance to ideal ground may not be present at all the nodes. Further, the nodes can be capacitively coupled to each other. To avoid inverting a large nonbanded matrix, a small capacitance to ground is added to a node that did not have any capacitance to ground, and a small series inductance is added to any floating capacitor that did not have any series inductance. Approximate closed-form expressions to compute the values of these capacitances to ground and series inductances have been proposed. The accuracy of the LIM-enabled transient simulation and the accuracy of the proposed closed-form expressions have been demonstrated. The memory and time complexity of the simulation for each time step have been shown to be O(Nn) each, where Nn is the number of nodes in the equivalent circuit. Stability condition is derived for the first time for multidimensional inhomogeneous RLC circuit. A upper bound of the time step is derived from the stability condition. Using this bound on the time step, the runtime of the overall transient simulation has been estimated to be approximately proportional to Nn2-2.5 for Nn in the order of millions. [ABSTRACT FROM AUTHOR]

Cyber-physical systems are ubiquitous in power systems, transportation networks, industrial control processes, and critical infrastructures. These systems need to operate reliably in the face of unforeseen failures and external malicious attacks. In this paper: i) we propose a mathematical framework for cyber-physical systems, attacks, and monitors; ii) we characterize fundamental monitoring limitations from system-theoretic and graph-theoretic perspectives; and ii) we design centralized and distributed attack detection and identification monitors. Finally, we validate our findings through compelling examples. [ABSTRACT FROM PUBLISHER]

An efficient and frequency-dependent model describing the crosstalk noise on power distribution networks due to inductive links in contactless 3-D ICs is presented. A two-step approach is followed to model the crosstalk effect. During the first step, the mutual inductance between the power distribution network and the inductive link is analytically determined. Due to the weak dependence of mutual inductance to frequency, a magnetostatic model is proposed for this step. The model includes the physical and electrical characteristics of both the on-chip inductor and the wires of the power distribution network. In this way, different power network topologies can be modeled facilitating noise analysis in the vicinity of the on-chip inductor. This approach is justified by the typical use of regular power network topologies in modern integrated circuits. In the second stage, the noise is assessed with SPICE simulations, considering the mutual inductance between the two structures from the first step and the resistance variations due to high frequency effects. Thus, an efficient, scalable, and accurate method for the analysis of the crosstalk effects due to inductive links is provided, without resorting on computationally expensive and time consuming full-wave simulations. Compared with the full-wave simulations, the induced noise is evaluated four orders of magnitude faster with the proposed model. The accuracy of the proposed model is within 10% of the respective noise computed with a commercial electromagnetics simulator using the finite element method. An analysis including the effect of substrate resistivity on the crosstalk noise is also presented. [ABSTRACT FROM AUTHOR]

The electric power grid is spatially and temporally complex, nonconvex, nonlinear, and nonstationary system with uncertainties at many levels. The integration of renewable sources of energy, such as wind and solar farms, energy storage, and plug-in hybrid electric vehicles, further adds complexity and challenges to efficient, reliable, and safe operation of electric power grids. A smart grid is aimed at improving power system’s reliability, security, sustainability, efficiency, and flexibility through distributed and coordinated intelligence at all levels of the electric power grid—generation, transmission, and distribution. The challenges faced in evolving a smart grid include variable and uncertain generation (such as wind and solar), stochastic load profiles and power flows, cyber attacks (unintentional and malicious), communication latencies and data loss, and so on. [ABSTRACT FROM PUBLISHER]

We have developed a grid network that broadcasts spikes (all-or-none events) in a multichip neuromorphic system by relaying them from chip to chip. The grid is expandable because, unlike a bus, its capacity does not decrease as more chips are added. The multiple relays do not increase latency because the grid's cycle time is shorter than the bus. We describe an asynchronous relay implementation that automatically assigns chip addresses to indicate the source of spikes, encoded as word-serial address-events. This design, which is integrated on each chip, connects neurons at corresponding locations on each of the chips (pointwise connectivity) and supports oblivious, targeted, and excluded delivery of spikes. Results from two chips fabricated in 0.25-μm technology are presented, showing word-rates up to 45.4 M events/s. [ABSTRACT FROM AUTHOR]

As the number of charging Plug-in Electric Vehicles (PEVs) increase, due to the limited power capacity of the distribution feeders and the sensitivity of the mid-way distribution transformers to the excessive load, it is crucial to control the amount of power through each specific distribution feeder to avoid system overloads that may lead to breakdowns. In this technical note we develop, analyze and evaluate charging algorithms for PEVs with feeder overload constraints in the distribution grid. The algorithms we propose jointly minimize the variance of the aggregate load and prevent overloading of the distribution feeders. [ABSTRACT FROM PUBLISHER]

We consider the problem of optimal reactive power compensation for the minimization of power distribution losses in a smart microgrid. We first propose an approximate model for the power distribution network, which allows us to cast the problem into the class of convex quadratic, linearly constrained, optimization problems. We then consider the specific problem of commanding the microgenerators connected to a microgrid, in order to achieve the optimal injection of reactive power. For this task, we design a randomized, leader-less, gossip-like optimization algorithm. We show how a distributed approach is possible, where microgenerators need to have only a partial knowledge of the problem parameters and of the state, and can perform only local measurements. For the proposed algorithm, we provide conditions for convergence together with an analytic characterization of the convergence speed. The analysis shows that, in radial networks, the best performance is achieved when we command cooperation among microgenerators that are neighbors in the electric topology. Numerical simulations are included to validate both the proposed model and the analytic results about the performance of the proposed algorithm. [ABSTRACT FROM PUBLISHER]

The article discusses issues relating to flexible alternating current (AC) transmission, which is the ninth in the "IEEE Spectrum" magazine's top 11 technologies of the decade for 2000s. Topics covered include the history of the technology, impact on the energy sector and on electric power distribution and speculations on future upgrades or developments.