Fig. 3c shows performance of the system under non-linear load and
sudden voltage swell. Before time t = .3 s, the system is under
steady-state conditions along with nominal grid voltage. At time t = .3
s, a sudden voltage swell (230–270 V) is observed. No appreciable
effect is observed in PV voltage (vpv), current (ipv) and power (Ppv) as
a result of swell. The load power is increased whereas PV power
remains the same, and hence a decrement in the grid current is
observed. Owing to an increment in voltage at PCC the VSC has to
feed reduced current to feed the same real power, hence a decrease in
VSC current is also observed. The dynamic performance of the system
is found satisfactory even under sudden voltage swell