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Power Quality and Utility Interface Issues
Published in Timothy L. Skvarenina, The Power Electronics Handbook, 2018
Wayne Galli, Timothy L. Skvarenina, Badrul H. Chowdhury, Hirofumi Akagi, Rajapandian Ayyanar, Amit Kumar Jain
Harmonic generation is attributed to the application of nonlinear loads (i.e., loads that when supplied a sinusoidal voltage do not draw a sinusoidal current). These nonlinear loads not only have the potential to create problems within the facility that contains the nonlinear loads but also can (depending on the stiffness of the utility system supplying energy to the facility) adversely affect neighboring facilities. IEEE 519-1992 [3] specifically addresses the issues of steady-state limits on harmonics as seen at the point of common coupling (PCC). It should be noted that this standard is currently under revision and more information on available drafts can be found at http://standards.ieee.org.
Harmonic Mitigation and Filters
Published in J.C. Das, Power System Analysis, 2017
Alternative technologies can be adopted to limit the harmonics at source, for example, phase multiplication, operation with higher pulse numbers, converters with interphase reactors, active wave-shaping techniques, multilevel converters, and harmonic compensation built into the harmonic-producing equipment itself to reduce harmonic generation.
Alkali metals in the attosecond pulse train
Published in Journal of Modern Optics, 2022
HHG refers to the problem of generating high-frequency pulses from a low-frequency one. Harmonic generation, generally speaking, is a feature of driven non-linear systems. In particular, when a very intense laser pulse is focused on an atomic gas, strong nonlinear laser-atom interactions can lead to the generation of harmonics of the optical frequency of the pulse of a very high order [1,2]. It is an extreme form of nonlinear frequency conversion and in general, only odd harmonics of the incident radiation frequency are emitted. The most significant manifestation is the existence of a plateau in the harmonics spectrum in which the harmonics up to the characteristic cutoff have fairly uniform intensity. Thus, HHG, as the specific form of secondary radiation, has recently become a base for attosecond pulses production [3–5].
Power Quality Analysis for Ship-Photovoltaic Power System: A Case Study
Published in Electric Power Components and Systems, 2018
Yuanchao Qiu, Chengqing Yuan, Yuwei Sun, Xujing Tang
In addition, the waveform distortions are expressed as harmonic generation in the electrical power system. Harmonics are produced by non-linear loads such as inductive motors and main propulsion, etc., these loads draw non-linear currents which when flowing through the power system impedances produce distortion in the voltage waveform, that finally affects the whole power system. Harmonics in current and voltage are frequency components that are integer multiple of the fundamental frequency of the electrical power system. The harmonic of the ship power system is usually described by two evaluated parameters, namely, the maximum single harmonic content and the THD. The maximum single harmonic contents of voltage and current are described by where Uh and fh denote the voltage harmonic content and the frequency harmonic content, respectively, and h denotes the harmonic order, i.e., an integer multiple of 60 Hz).