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Key, T. S.

Publications and source records attributed to Key, T. S..

Status of utility-interactive photovoltaic power conditioning technology

Design options for utility-interactive photovoltaic power conditioning technology for unit ratings from 2kW to 5 MW are compared. Line- and self-commutated inverter designs for both single and three-phase applications are described. Efficiency, weight, and cost projections are provided for comparing the design options. New circuit designs that take advantage of advances in power semiconductor devices are found to be the most promising. Hardware efficiencies from 95 percent for single phase to 98 percent for three-phase applications are found.

Key, T. S.↗

Intermediate power conditioners - Where are we now?

It has been recognized in the photovoltaic (PV) industry that even in the event of a dramatic reduction in the price of generating PV cells, the costs for the other components of the system represent still a major obstacle towards commercialization. A project was, therefore, initiated with the aim to develop baseline and conceptual power conditioner designs which would attempt to meet a specified set of cost and performance goals in the 30 to 200 kW (Intermediate) size. Resulting Intermediate Size Power Conditioner Studies led to a number of conclusions. There is a need for a set of guidelines or standards for utility interconnection. The advent of new devices with more power handling capability will change the desired topology.

Klein, J. W.↗

Residential photovoltaic power conditioning technology for grid connected applications

Major advances in photovoltaic (PV) Power Conditioning (PC) with respect to performance and low-cost potential have been made. Solutions have been obtained to interface and control problems related to adapting available inverter designs to the grid-connected, residential photovoltaic experiments. A description is presented to contributing research and development activities. Attention is given to aspects of residential systems experience, conceptual design studies, questions of optimum topology development, and promising advanced designs for residential PV provided by development efforts of the private sector.

Key, T. S.↗