Notch Filter–Assisted DC‐Link Stabilization for Improved Current Ripple Suppression in SLL Converter–Based BLDC Motor Drives

ABSTRACT Brushless DC motor (BLDCM) drives are highly sensitive to current and torque ripples, which can lead to reduced efficiency, increased acoustic noise, and degraded control performance. A major contributor to these ripples is the presence of undamped AC components in the DC‐link power (DCLP) supply, particularly during rapid switching and commutation events. The DC–DC converters are typically employed to regulate and provide the required input voltage to BLDCM drives; they do not inherently suppress these undamped AC components. To address this limitation, various filter‐based stabilization methods have been proposed, primarily relying on low‐pass filters (LPFs) or band‐pass filters (BPFs). However, such filters often demand complex coordination with active compensation loops, precise current references, and nonlinear interactions. In this context, this paper explores a notch‐filter (NF)–based stabilization approach for the DCLP supply in a super‐lift Luo (SLL) converter‐assisted BLDCM drive. The SLL converter is mainly employed for voltage regulation, while the NF is integrated to suppress the undamped AC signals in the DC‐link. A hardware prototype has been developed to validate the proposed design. Experimental results confirm that the suggested stabilization strategy effectively enhances DC‐link stability and improves the overall performance of the BLDCM drive.