Inverters That Mimic a Synchronous Condenser to Improve Voltage Stability in Power System

The shift to renewable energy generation increases risks of frequency and voltage instability. This transition can cause significant voltage and frequency fluctuations during load changes, generation interruptions, and grid faults. One potential solution is the deployment of synchronous condensers to mitigate these issues; however, this approach may also increase operational and maintenance costs. To address this limitation, this paper proposes a method called the virtual synchronous condenser (VSCon) that enables renewable energy systems such as PV-solar energy systems or wind farms to emulate the behavior of synchronous condensers. Unlike traditional VSGs with simplified models, VSCon uses the mathematical equivalent circuit of a real synchronous condenser. This enables sub-transient and inertial behavior. Voltage support improves by adjusting sub-transient reactance, and frequency support enhances by tuning inertia and damping coefficients, thereby enhancing the local voltage and frequency stability. The proposed approach has been validated through case studies, demonstrating both its effectiveness and practicality.