University of Pittsburgh researchers have developed a novel method to transform a two-port impedance network (i.e., an electrical circuit composed of interconnected components) into an active, virtual resistance network (VRN). The resulting VRN is designed to consume zero power and eliminate all reactive elements in the impedance network. This novel approach is a low-cost, fast responding, reliable method to transform an impedance network from reactive to resistive. Full optimization of this method should result in resilient power grids preventing power system transient phenomena, congestion, and power imbalances.
AVATAR, a novel system to improve power grid resilience and stability has been developed. Based on the inclusion of two controllable voltage sources at the front and back end of an impedance network (e.g., a transformer), AVATAR can prevent voltage surges or other transient disruptions to power grids without loss of power.
Description
Power grids are increasingly under pressure from aging infrastructure, increased demands, extreme weather, and cyber security threats. Renewables are increasingly being integrated into power grids and while these improve grid resilience and reduce carbon emissions, the intermittent nature of these power sources challenges grid control, coordination, and stability. Power system transient phenomena are a result of sudden changes in system conditions that disturb the steady-state status of voltage, current, or frequency. It could create short-lived spikes in voltages or currents (i.e., surges) and can damage electrical equipment and cause downtime in businesses due to equipment damage and power interruption. With ever-increasing reliance on electrical equipment, there is a pressing need to develop a more resilient and efficient power grid to meet demands from consumers. This novel approach is designed to stabilize power grids by changing the nature of grid components from reactive – the underlying cause of many instability problems – to resistive, ensuring electrical networks are efficient and meet the needs of all users.
Applications
• Power grid stabilization
• Infrastructure systems
Advantages
Current solutions to manage inefficiencies in power grids are usually tailored to the local problems at the grid (e.g., harmonics, congestion, or loop flow) and cannot be broadly applied to solve all issues in the grid and enhance stability.
A novel Active, Virtual And resistive Transformers for Transmission and Distribution (T&D) systems, and Resources (AVATAR) is being developed as a generic solution to all causes of voltage and/or current surges. AVATAR uses two controllable voltage sources which are applied either side of the transformer, the most common component in power grids. These voltage sources change the characteristics of the transformer from reactive to resistive without loss of power and better control the voltage flow, improving the power grid performance and preventing power instability issues. AVATAR could be developed as an autonomous approach to improve efficiency at every step of the power grid from generation to transmission and distribution.
Invention Readiness
Computer stimulations demonstrated the theoretical feasibility of AVATAR to convert a transformer from reactive to purely resistive. The power delivered from the grid and consumed by the load was uniform suggesting no power loss or surge.
IP Status
Patent Pending
