MUMBAI, India, May 29 -- Intellectual Property India has published a patent application (202631062890 A) filed by C. V. Raman Global University, Bhubaneswar, Orissa, on May 18, for 'a pll-less multi-mode control methodology and system for distributed energy resource fed voltage source inverters.'
Inventor(s) include Dr. Pragnyashree Ray; Dr. Pradyumna Kumar Behera; Dr. Laxmidhar Senapati; and Dr. Priyanka Sen.
The application for the patent was published on May 29, under issue no. 22/2026.
According to the abstract released by the Intellectual Property India: "The present invention discloses a phase-locked loop less multi-mode control methodology and system for a distributed energy resource fed voltage source inverter in an AC microgrid integrating photovoltaic generation and battery energy storage. The invention enables a single two-level threephase VSI to operate seamlessly in three distinct control modes - constant power control mode for normal grid-connected operation, constant AC voltage grid-forming mode for islanded operation, and constant DC-bus voltage mode for reactive power compensation - without employing any phase-locked loop based synchronization mechanism in any mode. The control framework is based on unit voltage template generation derived from filtered fundamental voltage components during grid-connected operation and from internally created rated-frequency sinusoidal signals during islanding, enabling consistent reference generation across all modes without structural modification. A pre-filtering stage employing an infinite impulse response inverse peak filter centered at the fundamental frequency extracts disturbance-free fundamental voltage and current components from measured signals affected by harmonic distortion, voltage unbalance, and switching noise, ensuring accurate active and reactive power decoupling under non-ideal grid and load conditions. Active and reactive current components are extracted from the filtered inverter current using zero-crossing detection and sample-hold operations applied with reference to in-phase and quadrature unit templates, enabling decoupled current regulation without coordinate transformation. Automatic mode selection is governed by real-time monitoring of grid voltage magnitude, grid frequency, photovoltaic power availability, and battery state-of-charge against predefined thresholds. The invention eliminates computational burden associated with PLL-based coordinate transformations, improves dynamic response, and enhances robustness under grid disturbances, islanding events, and variable renewable energy availability, making it well-suited for practical deployment in distributed energy resource-based AC microgrids across residential, commercial, and industrial applications."
Disclaimer: Curated by HT Syndication.
