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Interleaving techniques in DC-DC converters enhance the operational redundancy and reduce the current ripple. However, the phase-shifted operation of the interleaved branches results in different mathematical models for high and low values of duty ratio. In applications such as renewable energy integration where wide variations in duty ratios are bound to occur due to the dynamic nature of the source, a single mathematical model cannot represent the interleaved converter for the entire duty ratio range. This is due to the fact that when the duty ratio increases beyond a threshold the conduction period of the interleaved phases overlap, resulting in a different set of operating modes of the converter. Existing literature has not investigated this effect while formulating the mathematical model as it becomes evident only when the parasitic circuit elements are accounted for in the model. Firstly, this paper presents an extensive small-signal of a two-phase interleaved boost converter considering all the internal voltage drops due to parasitic circuit elements. Secondly, this work investigates the variations in the mathematical model due to the presence of parasitic circuit elements, when the interleaved converter operates in phase-shifted mode over a wide range of duty ratio. The proposed model is tested by simulation in MATLAB/Simulink® and validated with a 300W hardware prototype. [ABSTRACT FROM AUTHOR]

In a power system, the incurred transmission loss and the associated sensitivity factors are dependent on the selection of the slack bus and the dispatch. In this paper, a fast two-stage, hydro-thermal generation scheduling process, which is also inclusive of the system power loss, is proposed. A novel approach towards estimating power loss sensitivity factors is presented which is independent of the choice/location of the slack bus in the network. In addition to this, the approach identifies the loss incurred by the operation of different market players including the generation and distribution companies for penalizing. Mixed integer linear programming is used to model the said optimal day-ahead scheduling problem. The two-stage process employed is such that the first stage is applied only in the planning stage, while second is a fast responsive algorithm suitable for very short-term applications. A real network, Vietnam Power Grid, is used for testing this proposed approach, and the results obtained demonstrated that there is significant reduction in the electricity cost and total transmission loss. [ABSTRACT FROM AUTHOR]