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.

A Versatile Three Phase Oscillator

Abstract: This paper presents the design and performance of a versatile three phase oscillator The oscillator is built using digital circuits It provides five distinct output waveforms: sine, triangle, square, trapezoidal and symmetrically clipped sine waves Independent signals control output frequency, amplitude and phase sequence The oscillator has been built and successfully used in a cycloconverter powering a linear synchronous motor

Large signal dynamic stability analysis of synchronised current controlled modulators. Application to sine wave high power inverters

Abstract: This paper deals with a new application of DC/DC regulators for the achievement of a sine wave output More particularly, synchronised current control modulator MC2 in a buck configuration is discribed to generate an AC waveform at 50 Hz Large signal simulation is detailed which concludes on the setting of a sawtooth corrective network to avoid the structural instability for V0 >> V/2 It is shown that small signal analysis can be applied for such application and mathematical models for discontinuous and continuous conduction modes are presented The paper ends with the test of a breadboard generating a pure sine wave without harmonic content at 85 % efficiency

Stochastic resonance with different periodic forces in overdamped two coupled anharmonic oscillators

Abstract: We study the stochastic resonance phenomenon in the overdamped two coupled anharmonic oscillators with Gaussian noise and driven by different external periodic forces. We consider (i) sine, (ii) square, (iii) symmetric saw-tooth, (iv) asymmetric saw-tooth, (v) modulus of sine and (vi) rectified sinusoidal forces. The external periodic forces and Gaussian noise term are added to one of the two state variables of the system. The effect of each force is studied separately. In the absence of noise term, when the amplitude f of the applied periodic force is varied cross-well motion is realized above a critical value (fc) of f. This is found for all the forces except the modulus of sine and rectified sinusoidal forces. For fixed values of angular frequency ω of the periodic forces, fc is minimum for square wave and maximum for asymmetric saw-tooth wave. fc is found to scale as Ae0.75ω + B where A and B are constants. Stochastic resonance is observed in the presence of noise and periodic forces. The effect of different forces is compared. The stochastic resonance behaviour is quantized using power spectrum, signal-to-noise ratio, mean residence time and distribution of normalized residence times. The logarithmic plot of mean residence time τMR against 1/(D − Dc) where D is the intensity of the noise and Dc is the value of D at which cross-well motion is initiated shows a sharp knee-like structure for all the forces. Signal-to-noise ratio is found to be maximum at the noise intensity D = Dmax at which mean residence time is half of the period of the driving force for the forces such as sine, square, symmetric saw-tooth and asymmetric saw-tooth waves. With modulus of sine wave and rectified sine wave, the SNR peaks at a value of D for which sum of τMR in two wells of the potential of the system is half of the period of the driving force. For the chosen values of f and ω, signal-to-noise ratio is found to be maximum for square wave while it is minimum for modulus of sine and rectified sinusoidal waves. The values of Dc at which cross-well behaviour is initiated and Dmax are found to depend on the shape of the periodic forces.

Abnormality detecting apparatus for rotational angle detecting apparatus

Abstract: PROBLEM TO BE SOLVED: To correctly detect the abnormalities of a rotational angle detecting apparatus that uses a resolver. SOLUTION: The resolver 30 outputs a sine wave phase output signal and a cosine wave phase output signal excited by a sine wave signal, amplitude-modulated, in response to a rotation angle of a rotor 31 to a stator 32 and having amplitude changes with a phase difference of π/2. A sine wave phase amplitude calculating section 61 and a cosine wave phase amplitude calculating section 62 calculate the amplitudes of the sine wave phase output signal and the cosine wave phase output signal. A rotation angle calculating section 63 calculates the rotation angle θ by using the amplitudes. An abnormality determining section 68 tentatively determines an abnormality of the resolver 30, when the square root of the sum of squares of the amplitudes does not lie continuously within a predetermined range, and determines the abnormality of the resolver 30, if such conditions continues further. The abnormality determining section 68 avoids determination of the abnormality, when the calculated rotation angle indicates a rotation of the rotor 31 with respect to the stator 32 as 0 or 2π. COPYRIGHT: (C)2006,JPO&NCIPI

ALE behavior for two sinusoidal signal models

Abstract: The adaptive line enhancer (ALE) weight covariance matrix is determined for a complex monochromatic sine wave signal in an independent circular Gaussian noise background. The weight covariance matrix is shown to differ significantly from that obtained when the signal is a narrow-band sine wave process. In spite of this result, the misadjustment factors which characterize the mean-norm squared error behavior of the ALE are essentially indistinguishable for small values of the adaptation parameter-noise power product (μσ2).