Sökning: "Pulse-width modulation"
Visar resultat 1 - 5 av 39 avhandlingar innehållade orden Pulse-width modulation.
1. Pulse-Width Modulated RF Transmitters
Sammanfattning : The market for wireless portable devices has grown signicantly over the recent years.Wireless devices with ever-increased functionality require high rate data transmissionand reduced costs. LÄS MER
2. Modulation, efficiency and lifetime of two-level and multilevel converters for a hydropower application
Sammanfattning : Along with the integration of the renewable energy in the electrical grid, the pumped-storage hydropower has gained more and more attention due to its fast response and energy storage ability. To have a higher overall efficiency and more flexibility of the system, variable speed is preferred in the operation of the pumped-storage hydropower applications. LÄS MER
3. Control and Analysis of Pulse-Modulated Systems
Sammanfattning : The thesis consists of an introduction and four appended papers. In the introduction we give an overview of pulse-modulated systems and provide a few examples of such systems. Furthermore, we introduce the so-called dynamic phasor model which is used as a basis for analysis in two of the appended papers. LÄS MER
4. Modeling and Control of Voltage Source Converters Connected to the Grid
Sammanfattning : This thesis deals with the modeling and control of pulse width modulated (PWM) voltage source converters connected to the grid. When voltage source converters are connected to the grid, the power quality and the dynamic performance are affected by the line filter connected between the converter and the grid, and by nonlinearities caused by the switching converter. LÄS MER
5. Reduction of Audible Noise of a Traction Motor at PWM Operation
Sammanfattning : A dominating source for the radiated acoustic noise from a train at low speeds is the traction motor. This noise originates from electromagnetic forces acting on the structure resulting in vibrations on the surface and thus radiated noise. It is often perceived as annoying due to its tonal nature. LÄS MER