On the Commutation of Thyristors for High-Voltage Direct Current Transmission (HVDC)

The commutation of 8.5, 2.5 kA thyristors is experimentally investigated in a wide range of operation conditions. The dependence of the commutation turn-off time t(q) on the commutation di/dt, reverse voltage during commutation, forward blocking dv/dt, and temperature is presented in the range of 20-800 mu s. The t(q) of phase control thyristors (PCT) is carried out for three application relevant combinations of the ON-state voltage V-T and recovery time O(rr )and compared with that of the bidirectional PCT (BiPCT). Growth coefficients of t(q) are provided for practical magnitudes of di/dt, dv/dt, and temperature to be used in the design of high-power converters.

Automated summary

The commutation of 8.5, 2.5 kA thyristors is experimentally investigated in various operating conditions. The relationship between the commutation turn-off time t(q) and commutation di/dt, reverse voltage, forward blocking dv/dt, and temperature is presented. The growth coefficients of t(q) are provided for practical magnitudes of di/dt, dv/dt, and temperature for the design of high-power converters.