Quantitative power loss analysis and optimisation in nth-order low voltage multilevel converters

Focusing on cascaded H-bridge converters for grid-tie battery energy storage, a practical, analytical method is derived to evaluate the switching-associated power loss in multilevel converters, evaluated from a number of sources of loss. This new method is then used to find performance trends in the use of converters of increasing order over a range of switching frequencies. This includes an experimental analysis into predicting the performance of MOSFET body diodes. Our analysis with this model shows that a multilevel converter can have lower losses than the equivalent single bridge, three-level converter, particularly at higher switching frequencies, due to the availability of suitable switching devices. It also has interesting implications for enabling the use of cutting-edge non-silicon power switching devices to further improve potential efficiencies

The design of high efficiency power amplifiers for in-car audio use

SIGLEAvailable from British Library Document Supply Centre-DSC:DXN036338 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Effect of dead time on harmonic distortion in class-D audio power amplifiers

A model is described for predicting the harmonic levels introduced by the use of dead time in class-D, PWM-driven audio power output stages. The model demonstrates that the harmonic levels are a function of load impedance, modulation depth, dead time and switching frequency. In addition, measurements show that, for audio applications, dead time is the dominant cause of power stage nonlinearit