The system matrices optimization order reduction method calculates models of lower order but of high complexity. Secondary conditions can be formulated to calculate reduced systems with low complexity. One of the methods to find these secondary conditions is exploiting genetic algorithm in order to perform a global search within the search space and in advanced methods tabu search algorithm is used to perform a local search within the region found by the genetic algorithm. Another solution is proposed to simplify the complexity of the reduced order system and to reduce the computation effort.