Dynamic programming and Munkres algorithm for optimal photovoltaic arrays reconfiguration

In this paper, an original formulation of the control problem for optimal PV array reconfiguration, following a Total Cross Tied layout, is proposed. The formulation follows the well-known subset sum problem, which is a special case of the knapsack problem. The reconfiguration is a measure devoted to mitigate the mismatch effect and maximize the output power of small photovoltaic plants under non-homogeneous working conditions. Therefore, reconfiguration means changing the connections of the solar panels adaptively by a dynamic switching matrix. The control system implements an easy dynamic programming algorithm to change the switches layout. The use of the Munkres assignment method in a post-processing module makes the algorithm able to obtain the optimum configuration for which it is possible to balance and minimize the aging of the switches within the switching matrix. (C) 2015 Elsevier Ltd. All rights reserved.