This page is part of a course at Michigan Tech under Dr. Pearce.
Literature
Combined low-cost, high-efficient inverter, peak power tracker and regulator for PV applications
Enslin, J.H.R.; Snyman, D.B., "Combined low-cost, high-efficient inverter, peak power tracker and regulator for PV applications," Power Electronics, IEEE Transactions on , vol.6, no.1, pp.73,82, Jan 1991 doi: 10.1109/63.65005
A novel compound power converter that serves as a DC-to-AC inverter, maximum power point tracker (MPPT), and battery charger for stand-alone photovoltaic (PV) power systems is introduced. A theoretical analysis of the proposed converter is performed, and the results are compared with experimental results obtained from a 1.5 kW prototype. The overall cost of PV systems can thus be reduced by using load management control and efficiency-optimization techniques. Power flow through the converter is controlled by means of a combination of duty cycle and output frequency control. With load management, large domestic loads, such as single phase induction motors for water pumping, hold-over refrigerators, and freezers, can be driven by day at a much higher energy efficiency. This is due to the high efficiency of the inverter with high insolation, and because the inverter uses the energy directly from the solar array. The battery loss component is thus reduced
Optimum sizing of photovoltaic-energy storage systems for autonomous small islands
J. K. Kaldellis, D. Zafirakis, and E. Kondili, “Optimum sizing of photovoltaic-energy storage systems for autonomous small islands”, International Journal of Electrical Power & Energy Systems, vol. 32, no. 1, pp. 24–36, Jan. 2010.
The electrification of autonomous electrical networks is in most cases described by low quality of electricity available at very high production cost. Furthermore, autonomous electrical networks are subject to strict constraints posing serious limitations on the absorption of RES-based electricity generation. To by-pass these constraints and also secure a more sustainable electricity supply status, the concept of combining photovoltaic power stations and energy storage systems comprises a promising solution for small scaled autonomous electrical networks, increasing the reliability of the local network as well. In this context, the present study is devoted to develop a complete methodology, able to define the dimensions of an autonomous electricity generation system based on the maximum available solar potential exploitation at minimum electricity generation cost. In addition special emphasis is given in order to select the most cost-efficient energy storage configuration available. According to the calculation results obtained, one may clearly state that an optimum sizing combination of a PV generator along with an appropriate energy storage system may significantly contribute on reducing the electricity generation cost in several island electrical systems, providing also abundant and high quality electricity without the environmental and macroeconomic impacts of the oil-based thermal power stations.
Improved Energy Capture in Series String Photovoltaics via Smart Distributed Power Electronics
L. Linares, R. W. Erickson, S. MacAlpine, and M. Brandemuehl, “Improved Energy Capture in Series String Photovoltaics via Smart Distributed Power Electronics”, in Twenty-Fourth Annual IEEE Applied Power Electronics Conference and Exposition, 2009. APEC 2009, 2009, pp. 904–910.
This paper proposes an improved module integrated converter to increase energy capture in the photovoltaic (PV) series string. Prototypes for self-powered, high efficiency dc-dc converters that operate with autonomous control for tracking the maximum power of solar panels locally and on a fine scale are simulated, built and tested. The resulting module is a low-cost, reliable smart PV panel that operates independently of the geometry and complexity of the surrounding system. The controller maximizes energy capture by selection of one of three possible modes: buck, boost and pass-through. Autonomous controllers achieve noninteracting maximum power point tracking and a constant string voltage. The proposed module-integrated converters are verified in simulation. Experimental results show that the converter prototype achieves efficiencies of over 95% for most of its operating range. A 3-module PV series string was tested under mismatched solar irradiation conditions and increases of up to 38% power capture were measured.
Photovoltaic converter system suitable for use in small scale stand-alone or grid connected applications
J. A. Gow and C. D. Manning, “Photovoltaic converter system suitable for use in small scale stand-alone or grid connected applications”, Electric Power Applications, IEE Proceedings -, vol. 147, no. 6, pp. 535–543, Nov. 2000.
Of the commercially-available solutions for the conversion of energy from photovoltaic arrays into a usable form, a large number consist of systems which have been developed for a dedicated application and are thus very inflexible. Those that are available as a generic module for use in a variety of environments are often restricted to a single mode of operation, for example utility supply only. A generic modular photovoltaic power conversion system is presented, aimed at single-phase applications which can supply passive AC and DC loads with a regulated voltage or by way of a maximum power tracking system with the maximum power available from the array. In addition a live AC load such as the utility can be supplied with maximum array power. The system is small, light and can be constructed from readily available components.