A strategy for improving the SHEPWM commutation speed of CSI through hybrid switches

High-power current source inverters (CSI) usually operate at a low switching frequency to reduce loss. To suppress low-order harmonics and simplify filter design, the selective harmonic elimination pulse width modulation (SHEPWM) technique is feasible common strategy in industrial applications. This paper proposes an operational that uses H7 inverter (H7-CSI) with hybrid switches perform SHEPWM technique. On basis of retaining conventional H6 bridge, commutation speed CSI improved by additional shunt-connected high-performance power switch. The proposed scheme solves problem CSIs built low-speed (such as GTOs) may have difficulty for implementing setting widths null states, while further reducing losses acceptable cost. In addition, mitigating influence overlap-time optimizing driving signal converter bridge. Finally, simulation experiments verified effectiveness scheme.