DVAR

Dynamic VAR compensation, commonly abbreviated DVAR, refers to a category of power-electronics-based devices designed to provide or absorb reactive power to regulate voltage on electrical networks. DVAR systems are used to improve voltage stability, reduce voltage sags, and mitigate flicker on transmission and distribution infrastructures. They typically operate alongside traditional capacitor banks and reactors as part of an overall power quality strategy.

A DVAR system typically comprises a high-power converter connected to the grid, often through transformers, and may include energy storage or a DC link in some configurations. Control is achieved with voltage-based algorithms (Q-V control) and, in more advanced deployments, with automated VAR optimization coordinated by energy management systems or SCADA. The device rapidly injects or absorbs reactive power in response to voltage deviations, following predefined curves or droop characteristics to maintain target voltage levels and improve dynamic performance.

Applications span transmission and distribution networks, industrial facilities, and substations that require enhanced voltage regulation, reduced capacitor switching, and better handling of power-quality disturbances. DVAR solutions offer fast response and precise control compared with fixed capacitor banks, making them particularly effective during transient events and during voltage sags or disturbances.

Note: DVAR is an acronym with multiple possible meanings in different fields; in electrical engineering, it most commonly denotes Dynamic VAR compensation devices used for voltage regulation and reactive-power management.