No description available.

No description available.

Static power converters produce harmonics due to the nature of the conversion process. This paper will investigate two variations of current mode control for three-phase power converters ensuring reduced harmonic pollution and power factor improvement. The first method employed uses a Fryze current reference and the second method utilises a balanced three-phase sinusoidal reference. Both control techniques are simulated under unbalanced and distorted supply conditions using the PSIM simulation platform. The results are presented showing that using the Fryze current reference is the best choice.

Abstract-- Static power converters produce harmonics due to the nature of the conversion process. This paper will investigate the effect on the power factor of a sinusoidal and Fryze current reference on a PWM boost type rectifier. It has been shown in previous papers that a Fryze current ref is best. This paper will develop a mathematical model, based on the single sided Fourier expansion. Using this mathematical model it will be shown that even though a high harmonic content could be present in a Fryze controlled PWM boost type rectifier, the power factor has been optimally improved.

Characteristic features of the long atmospheric waves are discussed on the basis of spherical harmonic analysis of global weather charts for September 1957. At first, there is a discussion of the Trapezoidal and Simpson's numerical integration rules as applied to the computation of the Spherical harmonic coefficients. [...]

Spectral analysis (primarily in terms of spherical harmonics) is applied to the atmospheric dynamical equations in general, to truncated barotropic systems in particular and, in addition, to the global geopotential height field of the 500 mb surface for September 1957. [...]

Diss. (sammanfattning) Uppsala : Univ., 2005. / Härtill 4 uppsatser.

Inaug.-diss.--Munich. / Lebenslauf.

Inaug.-dis.--Königsberg.

Inaug.-diss.--Munich. / Lebenslauf.