Phase Compensation Multiresonant Control of CVCF PWM Converters

In this paper, phase compensation is proposed for a multiple resonant control (MRSC) scheme to compensate system delays on the basis of phase compensation repetitive control (RC). The inherent relationship between RC and resonant control (RSC) is comprehensively developed: the partial equivalence between RC and MRSC, the advantages and disadvantages of MRSC over RC-much faster convergence rate at the cost of heavier parallel computation burden. Stability criterion of MRSC systems, zero-phase compensation at each harmonic frequency, and rules of thumb for choosing RSC gains are developed for synthesis of phase compensation MRSC. The proposed phase compensation scheme enables MRSC to independently choose compensation phase angle and control gain at each resonant frequency. Accurate phase compensations and optimal weighted control gains at each selected harmonic frequency enable MRSC systems to significantly improve the control performance: wide stability range, high tracking accuracy, and fast error convergence rate. Experimental results of a three-phase PWM inverter illustrate the validity of the phase compensation MRSC scheme.