scispace - formally typeset
Search or ask a question
Topic

Sine wave

About: Sine wave is a research topic. Over the lifetime, 12183 publications have been published within this topic receiving 93013 citations. The topic is also known as: sinusoid.


Papers
More filters
Journal ArticleDOI
TL;DR: Experimental results indicate the effectiveness of the modulator and control system in providing balanced voltages at the output of the LC filter even under highly unbalanced conditions with nonlinear loads.
Abstract: The time integral of the output voltage vector of a three-phase inverter is often termed the inverter flux vector. This paper addresses the control of a three-phase four-leg sine-wave output inverter having an LC filter at its output, by controlling the flux vector in three dimensions. Flux vector control has the property that an output filter resonance is actively damped by an output voltage control loop alone. Furthermore, an inverter switching action inherently regulates the output voltage rapidly against dc-bus voltage variations. The flux vector control of sine-wave output inverters finds several applications in three-phase four-wire systems. This paper presents a flux modulation method for three-phase four-leg inverters feeding unbalanced and nonlinear loads. All the necessary steps for the digital implementation of the flux modulator are presented. The switching behavior of the modulator has been evaluated, which is useful for the variable fundamental frequency applications of the inverters. To provide experimental validation, the modulator is implemented as a part of the control system for a stand-alone three-phase four-leg inverter with an LC filter at its output. Control system details are also provided. Experimental results indicate the effectiveness of the modulator and control system in providing balanced voltages at the output of the LC filter even under highly unbalanced conditions with nonlinear loads. The resonance damping and voltage regulation properties of the modulator are also apparent from the experimental results.

42 citations

Journal ArticleDOI
TL;DR: These three waveforms are compared in terms of their analytical equations to find a means of distinguishing them experimentally and a Fourier analysis of the variation of tangent angle with arc length is suggested as the best method of discrimination.

42 citations

Journal ArticleDOI
TL;DR: The model predicts that increasing the number of samples per period nonlinearly reduces the difference between measured and ideal root-mean-square (rms) values, and this behavior was confirmed through measurements with thermal converters.
Abstract: Synthesizing Josephson stepwise approximated sine waves to produce an AC quantum standard is limited by errors in the waveform transitions between quantized voltages. Many parameters have an impact on the shape of the transients. A simple model with a single equivalent time constant can be used to evaluate the influence of these parameters. Measurements of the transients allow establishment of the value of the equivalent time constant and prediction of the response to variations of the parameters. We have experimentally confirmed the influence of changes in the bias current used for the quantized voltages and in the microwave power applied. Under usual operating conditions, the model predicts that increasing the number of samples per period nonlinearly reduces the difference between measured and ideal root-mean-square (rms) values. This behavior was confirmed through measurements with thermal converters.

42 citations

Journal ArticleDOI
TL;DR: The results show that the voltage waveform of oscillatory neurons can be predictive of their preferred frequency and thus the network oscillation frequency.
Abstract: Many oscillatory networks involve neurons that exhibit intrinsic rhythmicity but possess a large variety of voltage-gated currents that interact in a complex fashion, making it difficult to determine which factors control frequency. Yet these neurons often have preferred (resonance) frequencies that can be close to the network frequency. Because the preferred frequency results from the dynamics of ionic currents, it can be assumed to depend on parameters that determine the neuron's oscillatory waveform shape. The pyloric network frequency in the crab Cancer borealis is correlated with the preferred frequency of its bursting pacemaker neurons anterior burster and pyloric dilator (PD). We measured the preferred frequency of the PD neuron in voltage clamp, which allows control of the oscillation voltage range and waveforms (sine waves and realistic oscillation waveforms), and showed that (1) the preferred frequency depends on the voltage range of the oscillating voltage waveform; (2) the slope of the waveform near its peak has a strongly negative correlation with the preferred frequency; and (3) correlations between parameters of the PD neuron oscillation waveform and its preferred frequency can be used to predict shifts in the network frequency. As predicted by these results, dynamic clamp shifts of the upper or lower voltage limits of the PD neuron waveform during ongoing oscillations changed the network frequency, consistent with the predictions from the preferred frequency. These results show that the voltage waveform of oscillatory neurons can be predictive of their preferred frequency and thus the network oscillation frequency.

42 citations

Patent
Edward E. Bowles1
26 Nov 1996
TL;DR: In this article, a multistep inverter uses multiple inverter H-bridges connected in series to piecewise approximate a sine wave, bypassing or switching into service as required for sinewave synthesis.
Abstract: A multistep inverter uses multiple inverter H-bridges connected in series to piecewise approximate a sine wave. The inverter H-bridges are bypassed or switched into service as required for sinewave synthesis. After a step is switched in, it creates its portion of the sine wave. Each step is further smoothed using pulse width modulation which leads to a smoother sine wave with the consequent advantages of lower distortion, smaller and lighter filtering circuits, and lower conversion losses during transistor switching.

42 citations


Network Information
Related Topics (5)
Voltage
296.3K papers, 1.7M citations
79% related
Signal
674.2K papers, 4.5M citations
78% related
Artificial neural network
207K papers, 4.5M citations
77% related
Control theory
299.6K papers, 3.1M citations
77% related
Robustness (computer science)
94.7K papers, 1.6M citations
77% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202378
2022157
2021138
2020253
2019344
2018336