We assumed that charging power control will complement
when the LFC capacity is insufficient to accommodate the
fluctuation; hence, the lack of LFC capacity from ACE is
dispersed to all PHEVs in the area as shown in Fig. 10. More
precisely, LFC signal fLFC calculated from (3) is dispersed to all
PHEVs; then, PHEVs control the charging power on the basis
of frequency f and LFC signal fLFC as shown in Fig. 2. These
controls are equivalent to the LFC operation of thermal or
hydro power generators. In other words, the control with f,
which is corresponding to the governor with speed-droop
operation, will handle the fluctuation cycle from a few seconds
to a few minutes; the control with fLFC , which is corresponding
to LFC operation, will handle the fluctuation cycle from a few
minutes to 20 minutes.