Augmentation of Generalized Multivariable Grid-Forming Control for Power Converters with Cascaded Controllers

The classic design of grid-forming control strategies for power converters\nrely on the stringent assumption of the timescale separation between DC and AC\nstates and their corresponding control loops, e.g., AC and DC loops, power and\ncascaded voltage and current loops, etc. This paper proposes a multi-input\nmulti-output based grid-forming (MIMO-GFM) control for the power converters\nusing a multivariable feedback structure. First, the MIMO-GFM control couples\nthe AC and DC loops by a general multivariable control transfer matrix. Then,\nthe parameters design is transformed into a standard fixed-structure H-infinity\nsynthesis. By this way, all the loops can be tuned simultaneously and optimally\nwithout relying on the assumptions of loop decoupling. Therefore, a superior\nand robust performance can be achieved. Experimental results verify the\nproposed method.\n