Issues on solar-generator-interfacing with voltage-fed converter

Reliably operating solar-energy systems composing of solar arrays and their interfacing converters are of prime importance to maximize the solar-energy harvesting. The paper investigates the solar-generator-interfacing problems in terms of voltage-fed maximum-power-point tracking converters and shows that there are two main reasons for the observed stability problems of which the one is the violation of Kirchhoff's current law governing the operation of the solar generator and the other the phenomenon known as negative resistance oscillation. In practice, this means that the voltage-fed converter can reliably operate only in the voltages higher than the maximum-powerpoint voltage. Practical evidence is provided based on a coupled-inductor superbuck converter.