Abstract. The problem of structural-parametric optimization of system for uninterruptible power supply of responsible consumers is considered. Mathematical models of the problem are developed. An economic criterion (minimization of capital investment or the annual cost) is taken for the optimality criterion, while required level of power supply system reliability with the account for redundancy of the uninterruptible sources is considered as the constraints. The dependence of the efficiency coefficient for parallel-working static uninterruptible power supply units from their load is investigated. Based on analysis of methods of discrete optimization problem solution, the method of "branches and limits" is justified. A developed computer program for solution of the problem is presented. As an example, the problem of the structural and the parametric optimization of the uninterruptible power supply system for specific initial conditions is considered. 

Keywords: optimization, uninterrupted power supply system, responsible consumer, discounted costs, capital inputs, electric reliability

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