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            EV fleet in this study. Simulations to investigate the impact of varying
            threshold values on revenue are presented here. As the threshold value
            increases in Fig. 16.12, the initial revenue drop gets smaller; however, the
            revenue sharply decreases as the threshold increases from 20 to 60 kW, indi-
            cating that most commitments failed to satisfy the constraints defined by
            Eqs. (16.22) and (16.23) because the required power adjustments exceeded
            the capacity of the EV fleet.



            16.5 Distributed optimization with asynchronous ADMM
            and V2G capabilities

            Sections 16.3 and 16.4 have summarized the modeling approaches and the
            performance metrics of the market integration strategies of the controllable
            EVs within microgrid scenarios. Various types of information have been
            considered in the planning problems, including monthly projection of load
            profile, renewable generation, and the aggregate EV energy demand.
            However, the resultant optimal power profile, that is, PtðÞ; tA½1; 2; ... ; TŠ,
            obtained from various market integration strategies, cannot be directly
            applied to control the individual vehicles, so additional steps are needed to
            disaggregate the aggregate power profile. In this section, we extend the
            previous evaluation approach on a monthly basis to an implementable day-
            by-day operation, whose objective is to allow multiple EV agents to follow
            the prescheduled aggregator’s power consumption profile in a decentralized
            and asynchronous fashion, using ADMM.
               Fig. 16.13 indicates the implementation architecture of the decentralized
            load following program, where each EV computes a local optimization prob-
            lem but exchanges information with the aggregator by limited amount of
            communication. The overall problem is defined as follows:





                                    Aggregator



                           Signal 1
                                      Signal 2   Signal N

                                                  ...
                       EV 1            EV 2                 EV N


            FIGURE 16.13 Distribute optimization paradigm.
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