Multi-objective and multi-period power dispatch of distributed generation model with penalties based on the concept of intrinsic cost

Abstract

Currently, distribution systems face the challenge of adapting to the new paradigm of smart grids. Among the main aspects requiring research, it is observed that the participation of generators, whose primary sources are both conventional and renewable, located in higher-voltage networks (sub-transmission), coexisting with supply from multiple points of the interconnected system, establishes the need to reformulate traditional economic dispatch models. In this work, a multi-objective and multi-period dispatch model for distributed generators and multi-point supplies from the interconnected system, considering the latter as equivalent generators, is proposed. Given the need to incorporate both the operating constraints of the generating units and all network constraints, an optimal power flow is used. The objective functions to be minimized in each dispatch period are: total operating cost, total carbon dioxide emissions produced by the generators, and total power losses. From the optimal values obtained, the marginal costs associated with the two endogenous variables not directly monetizable (emissions and losses) can be estimated using the concept of intrinsic cost. These serve to penalize contingencies due to the unavailability of a generator, particularly those from renewable primary sources due to their intermittency. Simulations are presented for a 24-hour (hourly period) real-time dispatch, on a system based on the modified IEEE-14 bus single-line diagram, operating at 132 kV. In particular, the effect of a wind farm on each dispatch, depending on its availability, is studied and discussed.