Research on Control Strategy of AC-DC-AC Substation Based on Modular Multilevel Converter

Figure 17

Simulation results without suppressing the negative-sequence current. (a) Phase voltage of AC grid. (b) Phase current of AC grid. (c) DC voltage. (d) DC component of the circulating current. (e) Capacitor voltage.

(a)

(b)

(c)

(d)

(e)