Design of electronic optimizer for solar electric drive system

Abstract

There has been considerable interest in the use of solar electrical converters for supplying electric drive motors in pumping schemes for rural areas. The optimum control of solar electric drive motors is desirable because it leads firstly, to higher apparent efficiency of solar energy conversion, and, secondly, to reduced cost per useful watt. Although the ‘fuel’ for solar drives is free, the cost of solar cells is high. Optimization means that smaller areas of solar panels are required, thus reducing the overall cost of the solar drive system. The present investigation has been directed towards the development of a reliable electronic controller, which would ensure stable and optimal performance characteristics of solar electric‐powered pumping scheme over a broad range of operating conditions. The design goals are low cost, reasonable accuracy, control capability and efficient utilization of the electrically converted solar power. The developed electronic optimizer provides constant voltage operation of the solar generator so that maximum power can be delivered to the drive motor for any light intensity. The main part of the optimizer is a servo chopper. The chopper operation is automatically adjusted so that the overall system efficiency is always maintained at a maximum value. Details of the electronic optimizer circuits are given and the overall system performance is investigated. Valuable information for the design and operation of the solar electric drive system with the electronic optimizer is gained from this analysis.

Maximum‐power operation of a stand‐alone PV system using fuzzy logic control

“…In general, if the sawtooth waveform has a DC offset E b ; the switch duty cycle can be written as [12] …”

A novel method to optimize photovoltaic generator operation

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