Finite-Time Settling Control Based Current Controller for Thyristor Dual Converter

A finite-time settling control (FTSC) is used aptly for digital control systems because of deadbeat performance. A thyristor converter, which is regarded as a voltage controller including a sampler and a holder, apparently is acceptable for FTSC-based current control. The output current of the converter, however, frequently overshoots the reference current on account of time delay due to line commutation. Application of the FTSC method to current control of thyristor dual converters is described. The authors introduce a softening filter, or interpolation method, in addition to the finite-time settling control to maintain a completely deadbeat performance. The proposal is verified by simulations and experiments.