Patent ID: 11909214
Assignee: SOUTHEAST UNIVERSITY
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  Y | IPC H

Claim 7:
8. The topology of a series-connected MMC converter with a small number of modules according to claim 7, wherein a modulation wave signal of the first half-bridge valve string 1 connected to the midpoint of the phase-A bridge circuit is (vSA1−vSB1)×(⅔×VM)/(N×VSM)−(vA−vB), VM being the voltage across the high-voltage DC port, N being the number of submodules in a half-bridge valve string, and VSM being the capacitor voltage of the submodules in the half-bridge valve string; and
a modulation wave signal of the second half-bridge valve string 2 connected to the midpoint of the phase-C bridge circuit is (vSB1−vSC1)×(⅔×VM)/(N×VSM)−(vB−vC), where three-phase modulation waves vA, vB, vC can be obtained by closed-loop control on the capacitor voltage of the valve strings or control over the AC-side voltages or currents.