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.

The growing penetration of renewable energy has reduced system inertia and damping, threatening grid stability. This paper proposes a novel control strategy that seamlessly integrates virtual synchronous generator (VSG) emulation with low-voltage ride-through (LVRT) capability for direct-drive permanent magnet synchronous generators (PMSGs). The unified control framework enables simultaneous inertia support during frequency disturbances and compliant reactive current injection during voltage sags—eliminating mode switching. Furthermore, the proposed strategy has been validated through both a single-machine model and actual wind farm topology. Results demonstrate that the strategy successfully achieves VSG control functionality while simultaneously meeting LVRT requirements.

As the market share of electric vehicles (EVs) increases year by year, their charging load forecasting has become a research hotspot and a difficulty. Aiming at the shortcomings of the current research on the charging probability prediction of EVs with different power levels, this paper proposes a multi-power-level EV charging probability prediction method. Firstly, based on the characteristics of electric vehicles, the power of charging facilities, and the travel habits of owners, the SOC mathematical models of charging start time, as well as the start and end state of charge, are established, and the different charging power selection models are established in combination with the parking time. Then, the Monte Carlo simulation method is used to predict the charging probability of electric vehicles with different power levels on typical dates such as working days, weekends, and holidays.

The increasing shift from traditional energy sources to renewable energy generation has heightened the risk of frequency and voltage instability. This transition may result in serious consequences, such as significant voltage and frequency fluctuations during sudden load changes, power 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 that enables renewable energy systems to emulate the sub-transient behavior of synchronous condensers, thereby enhancing local voltage and frequency stability. The proposed approach has been validated through case studies, demonstrating both its effectiveness and practicality.

The journal retracts the article titled “Inverters That Mimic a Synchronous Condenser to Improve Voltage Stability in Power System”