Evaluation of actively clamped resonant link inverter forlow-output harmonic distortion high-power-density power converters

The suitability of a soft-switched actively clamped resonant DC-link (ACRDCL) inverter for low-output harmonic distortion/high-power-density power conversion is evaluated. Modulation and control techniques for achieving low-output harmonic distortion are described. Performance and power density of the ACRDCL inverter are maximized through the optimal design of the clamp circuit, resonant components, and output filter components. The ACRDCL inverter simulation and design are validated experimentally. For the same output kilovoltamperes, efficiency and harmonic performance as the ACRDCL inverter, hard-switched designs are compared. Methods to increase the power density of the ACRDCL are proposed, including the use of recently developed nonpunchthrough insulated gate bipolar transistors     

Hexagonal /spl Sigma//spl Delta/ modulators in power electronics

Design techniques for /spl Sigma//spl Delta/ modulators from communications are applied and adapted to improve the spectral characteristics of high frequency power electronic applications. A high frequency power electronic circuit can be regarded as a quantizer in an interpolative /spl Sigma//spl Delta/ modulator. We review one dimensional /spl Sigma//spl Delta/ modulators and then generalize to the hexagonal sigma-delta modulators that are appropriate to three-phase converters. A range of interpolative modulator designs from communications can then be generalized and applied to power electronic circuits. White noise spectral analysis of sigma-delta modulators is generalized and applied to analyze the designs so that the noise can be shaped to design requirements. Simulation results for an inverter show significant improvements in spectral performance.     

Power quality and reliability

Industrial and commercial electricity consumers and utility companies that serve them need access to power quality and reliability (PQ&R) information. This article presents several case studies from industrial applications, providing a glimpse at the potential uses of corporate-wide PQ&R information gathering, aggregation, and reporting. The system has been independently tested by several industrial users, utilities and EPRI-PEAC. Deployment of monitors continues through individual industrial and commercial sites, corporate and utility programs, and cooperative program with the DOE (Department of Energy).