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Power components definitions contained in the IEEE Standard 1459-2000 for unbalanced three-phase systems with nonsinusoidal situations are represented in the frequency domain based on Fourier transform (FT). However, FT suffers from the high computational effort especially when the number of phases increases and it is unable to provide information concerning time content because it provides only an amplitude-frequency spectrum. On the other hand, the discrete wavelet transform (DWT) preserves both time and frequency information while reducing the computational effort through dividing the frequency spectrum into bands and thus overcomes the limitations of FT. In this paper the three-phase power components definitions contained in the IEEE Standard 1459-2000 are reformulated using the DWT and thus redefined in the time-frequency domain. Also in order to study system unbalance, the concept of symmetrical components is defined in the wavelet domain. The results obtained from applying the IEEE Standard definitions and the DWT-based definitions to balanced and unbalanced three-phase systems under nonsinusoidal operating conditions, indicate that the DWT-based definitions are very accurate and the problem of spectral leakages can be reduced by suitable choice of the mother wavelet and the wavelet family. The DWT-based definitions are useful in studying nonstationary waveforms. Index Terms--Active power, apparent power, Daubechies wavelet (dbl0), harmonics, nonsinusoidal conditions, reactive power, three-phase systems, wavelet transform (WT).

IEEE Standard 1459-2000 establishes that in an efficient electrical system, only the fundamental positive-sequence active power must be present. This paper proposes a new set of reference currents based on the IEEE Standard 1459-2000 for the control of a three-branch four-wire shunt active power compensator. Reactive, unbalance, and harmonic distortion phenomena can be cancelled out upstream from the point of connection, achieving maximum efficiency of the three-phase four-wire electrical system. In addition, a new current control and a three-dimensional space vector pulsewidth-modulation technique are proposed to develop a shunt active power compensator. Simulation and experimental results demonstrate that the proposed shunt active power compensator improves the upstream electrical quality of the power network, achieving maximum efficiency according to IEEE Standard 1459-2000 specifications. Index Terms--Active filters, active power compensators (APCs), current control, harmonic distortion, IEEE standards, power quality (PQ), pulsewidth modulation, reactive power.

In nonsinusoidal situations, power components definitions contained in the IEEE Standard 1459-2000 are based on a frequency-domain approach using Fourier transform (FT). The frequency-domain approach can provide amplitude-frequency spectrum while loosing time-related information. Moreover, the FT carries a heavier computational burden. To overcome these limitations, definitions of power components are reformulated in the wavelet domain using the discrete wavelet transform (DWT). Using the DWT preserves the information concerning time and frequency and also reduces the computational time and effort by dividing the frequency spectrum into bands or levels. The results of applying the reformulated definitions show that the problem of spectral leakage between wavelet levels can be minimized by suitably choosing the wavelet family along with suitable mother wavelet. The reformulated definitions could be useful for setting tariff and evaluating the quality of the electric energy supply especially when considering nonstationary waveforms where the Fourier transform-based power components definitions fail. Index Terms--Active power, apparent power, nonsinnsoidal conditions, power quality, reactive power, wavelet transform (WT).

This paper presents an overview on available tools and methods for the simulation of electromagnetic transients in power systems. Both off-line and real-time simulation tools are presented and discussed. The first objective is to give the reader an overview on the modeling and simulation capabilities in currently available state-of-the-art tools. The second objective is to provide perspectives on research topics and needed enhancements. Index Terms--Electromagnetic transients, EMTP, power system models, real-time digital simulation.

Ensuring self-coexistence among IEEE 802.22 networks is a challenging problem owing to opportunistic access of incumbent-free radio resources by users in co-located networks. In this study, we propose a fully-distributed non-cooperative approach to ensure self-coexistence in downlink channels of IEEE 802.22 networks. We formulate the self-coexistence problem as a mixed-integer non-linear optimization problem for maximizing the network data rate, which is an NP-hard one. This work explores a sub-optimal solution by dividing the optimization problem into downlink channel allocation and power assignment sub-problems. Considering fairness, quality of service and minimum interference for customer-premises-equipment, we also develop a greedy algorithm for channel allocation and a non-cooperative game-theoretic framework for near-optimal power allocation. The base stations of networks are treated as players in a game, where they try to increase spectrum utilization by controlling power and reaching a Nash equilibrium point. We further develop a utility function for the game to increase the data rate by minimizing the transmission power and, subsequently, the interference from neighboring networks. A theoretical proof of the uniqueness and existence of the Nash equilibrium has been presented. Performance improvements in terms of data-rate with a degree of fairness compared to a cooperative branch-and-bound-based algorithm and a non-cooperative greedy approach have been shown through simulation studies.

This paper describes a time domain technique for the detection of fundamental and harmonic components of voltages and currents, which is able to evaluate all the quantities required by IEEE Standard 1459-2000. The technique does not require any spectral analysis to separate the fundamental positive-sequence components from harmonic, negative-sequence and zero-sequence ones. In the paper the development of the proposed technique is presented for three-phase systems, both three-wires and four-wires, as well as for single-phase systems. The implementation of the proposed technique on a PC-based instrument is also described and experimental results are presented. Finally, accuracy specifications are investigated in the presence of the measurement transducers. Index Terms--Harmonic distortion, IEEE Standard 1459-2000, phase-locked loops (PLLs), power measurement, power quality (PQ).

IEEE Standard 1344-1995 [1] on measurement of synchronized phasors of power system currents and voltages has been revised and published as IEEE Standard C37.118-2005 [2]. This paper has been prepared by the IEEE Working Group who developed the revised version. The purpose of the paper is to acquaint the power engineering community of the availability and content of this new standard, highlight some of the key differences between the old and new versions, and introduce several applications of this powerful technology. Index Terms--Global positioning system (GPS) synchronized phasor, phasor measurement unit (PMU), power system measurements, synchrophasor, wide-area measurements.

This report is based on a survey of power engineering education resources in the U.S. and Canada similar to 12 earlier such efforts. This survey is conducted to determine the electric power engineering education resources available in Accreditation Board of Engineering and Technology (ABET)-accredited engineering programs in the U.S. and Canada for the 20115-2006 academic year. The report is limited to colleges and universities that replied to a questionnaire on a voluntary basis. For the 125 colleges and universities (115 U.S., 10 Canadian) that submitted data on their power programs, the report contains a list of faculty active during the 2005-2006 academic year with academic participation and professional experience, each school's research area and funding levels, Ph.D. and M.S. student enrollment by type of support and by domestic versus international, and each school's power course offerings with enrollments and other data. Index Terms--Courses, enrollments, faculty, graduate students, power engineering education, research, survey.

The use of environmentally clean photovoltaic (PV) dispersed generation will become more widespread in the future due to anticipated cost reductions in PV technology. This paper summarizes the results of a power quality (PQ) study performed on a PV generator in order to estimate the effects that inverter-interfaced PV dispersed generation might have upon the quality of electric power. Different interpretations of the harmonic distortion limits set in the IEEE 519-1992 standard are performed together with a comparison with the BC Hydro's harmonic current limits. This paper also includes a statistical analysis of all measurements recorded with the help of two PQ monitors, an evaluation of the results from a connection/disconnection test, and harmonic simulation results. Index Terms--Dispersed generation, harmonic distortion, IEEE standards, IEEE 519-1992, power quality, photovoltaic power generation.

This paper rigorously considers the concept of apparent power in unbalanced three-phase situations. The analysis shows that there are various related but different concepts that can be associated with the apparent power. In particular two approaches are covered, the one relating to the literature on the single-phase sinusoidal case, the other relating to the recent IEEE Standard 1459-2000. The underlying ideas for each concept are given; the relationship and the differences between them are thoroughly discussed. Index Terms--Active power, apparent power, power factor, unbalanced currents, unbalanced voltages.

Energy consumption is an important issue in body area networks (BANs). In this letter, we propose an energy efficient transmission power control scheme for IEEE 802.15.6 BANs, which can improve energy efficiency by adaptively adjusting the transmit power in an on-demand way to adapt to varying channel environments. Simulations are performed to evaluate the performance, and it is shown that the proposed power control scheme outperforms traditional ones in terms of energy efficiency without significant reliability degradation. [ABSTRACT FROM AUTHOR]

This report is based on a survey of power engineering education resources in the U.S. and Canada similar to 12 earlier such efforts. This survey is conducted to determine the electric power engineering education resources available in Accreditation Board of Engineering and Technology (ABET) accredited engineering programs in the U.S. and Canada for the 2001-02 academic year. The report is limited to colleges and universities that replied to a questionnaire on a voluntary basis. For the 115 colleges and universities (107 U.S., 8 Canadian) that submitted data on their power programs, the report contains a list of faculty active during the 2001-02 academic year with academic participation and professional experience, each school's research area and funding levels, Ph.D. and MS student enrollment by type of support and by domestic versus international, and each school's power course offerings with enrollments and other data. Index Terms--Courses, enrollments, faculty, graduate students, power engineering education, research, survey.

This study shows the problem of power saving mechanism (PSM) that sleep intervals of uplink (UL) connections do not synchronize with sleep intervals of downlink (DL) connections. That is, the energy of a mobile station (MS) is not really saved if the DL connections are in the sleep mode while the UL connections are in normal mode, and vice versa. To avoid the asynchronism of power saving (PS) between UL and DL connections, we invent a mechanism of DL connections regulating UL connections, called DL and UL Alignment (DUAL) scheme, to improve the energy efficiency for PS. Considering that the buffer size of MS is limited, DUAL uses the mean packet arrival rate of UL λu and a relatively safe threshold of buffer size QT as the parameters to estimate the maximum allowable waiting time to align the UL with the DL connections. To analyze the performance of DUAL, a system model of PS is proposed to evaluate the performance of DUAL under different conditions. The correctness of performance analysis of DUAL is validated by using simulation with realistic parameters. Numerical experiments show that DUAL improves the energy conservation significantly when UL traffic is greater than DL traffic.

In IEEE 802.11 wireless networks, a mobile station (MS) can power down the transceiver to save energy. To achieve power conservation, an access point (AP) periodically broadcasts beacons to notify the associated MSs about their traffic indications, and the MSs periodically wake up to listen to the beacons. The MS awake time scheduling is an important issue, which affects the number of simultaneously awake MSs to compete for access. We propose a power conservation scheme to optimally schedule the awake times among the MSs, such that the number of MSs awaking at the same time is minimal. Our study indicates that the proposed scheme demonstrates good performance in terms of frame loss and delay time. Index Terms--Access point (AP), power conservation, power save mode (PSM), wireless local area network (WLAN).

We address two issues of contemporary interest in the area of enhancing the performance of ad hoc networks, where the IEEE 802.11 distributed coordination function (DCF) is the adopted medium-access control (MAC). We investigate the effects that transmission power control and tuning carrier sensing (CS) threshold have on network throughput, and we study the interplay between them. To accomplish this, we develop a realistic analytical model that characterizes the transmission activities that are governed by the IEEE 802.11 DCF in a single-channel power-aware multihop wireless network. We observe that selecting a smaller CS threshold will severely impact the spatial reuse, whereas a larger CS threshold will yield excessive interference among concurrent transmissions. Accordingly, we discovered that performing power control has either a minor or negligible effect in both situations, respectively. Furthermore, when the CS threshold is selected appropriately, power control shows its effectiveness in reducing collisions and, hence, improving system performance. Finally, using our model, we demonstrate the potential adverse impacts of request-to-send/clear-to-send (RTS/CTS) control packets on the network capacity and compare its performance with the two-way basic access method. Index Terms--IEEE 802.11, modeling, physical carrier sensing (PCS), power control, throughput.

IEEE Standard 1344, Synchrophasors for Power Systems, was completed in 1995. It sets parameters required to ensure that phasor measurement will be made and communicated in a consistent manner. It specifies requirements for the timing signal used for phasor synchronization and the time code needed for input to a measurement unit. GPS is the recommended time source and IRIG-B is the basic format used for time communication. The standard requires correlating phasors computed from unsynchronized and synchronized sampling to a common basis. Timetagging accurately and consistently is essential for wide area comparison of phase. The standard specifies information exchange and control message formats. These include data output, configuration, and command messages. It includes 7 annexes that discuss the concepts covered in the body of the standard. Keywords: Synchrophasor, Synchronized phasor, Phasor

The improvement of transient stability of power system was one of the most challenging research areas in power engineer.The main aim of this paper was transient stability analysis and improvement of IEEE 9 bus system. These studies were computed using POWER WORLD SIMULATOR. The IEEE 9 bus system was modelled in power world simulator and load flow studies were performed to determine pre-fault conditions in the system using Newton-Raphson method. The transient stability analysis was carried out using Runga method during three-phase balanced fault. For the improvement transient stability, the general methods adopted were fast acting exciters, FACT devices and addition of parallel transmission line. These techniques play an important role in improving the transient stability, increasing transmission capacity and damping low frequency oscillations.

This tutorial paper discusses the drawbacks of the definitions of various types of powers found in the current IEEE Standard Dictionary of Electrical and Electronics Terms (IEEE Std. 100-88). With the exceptions of instantaneous power and active power, all remaining kinds of 'powers' are nonphysical. The concept of power factor in polyphase circuits is ambiguous. Examples that illustrate the shortcomings of many power definitions are included. The impact of these definitions on current power/energy metering practices are discussed. It is recommended that some definitions be either changed or eliminated from the IEEE Dictionary.

This report presents the results of an extensive survey of utility practices for synchronizing a generator to the power system. The survey was constructed to collect data defining the present utility practice of synchronizing, the types of schemes used, why they were selected, and how they have performed. The survey also collected data detailing the number of machines equipped with a manual, semi-automatic, or automatic synchronizing scheme. This data is categorized by generator prime mover type and load classification. KEY WORDS - Synchronizing, Automatic Synchronizer, Synchronizer, Generator Protection, Generator Control

The article focuses on the HVDC technology (high voltage direct current) is used to transmit electricity over long distances by overhead transmission lines or submarine cables. It mentions HVDC allows power transmission between unsynchronized AC transmission systems; and most HVDC links use voltages between 100 kV and 800 kV. A 1,100 kV link in China was completed in 2019 over a distance of 3,300 km with a power of 12 GW.