Energy-Driven Analysis of Electronically-Interfaced Resources for Improving Power System Dynamic Performance

This dissertation investigates the strengthening of power system dynamics with regard to electromechanical oscillations by using electronically-interfaced resources (EIR). The dissertation addresses (1) the modeling and control design of a flywheel energy storage system and a large-scale solar PV plant. The latest is enabled to participate in oscillation damping control without the need for power curtailment. (2) A new dynamic performance evaluation and coordination of damping controller is also developed to analyze systems with several critically low damping ratios. This is studied by using the system oscillation energy to define the total action and total action sensitivity, which allow the identification of control action that benefit exited modes, rather than fixed targeted modes. Finally, (3) this dissertation proposes a solution for the site selection of EIR-based damping controllers in a planning stage. The effect of wind power variability and correlation between geographically closed wind farms is modeled to analyze the system performance and determine the site selection that maximizes the probability of dynamic performance improvement. Mathematical description as well as simulations in different multi-machine power systems show the advantages of the methods described in this work. The findings of this thesis are expected to advance the state-of-the-art of power system control by effectively and efficiently utilizing the fast power capabilities of EIR in systems with high penetration of renewable energy

Oscillation energy based sensitivity analysis and control for multi-mode oscillation systems

This paper describes a novel approach to analyze and control systems with multi-mode oscillation problems. Traditional single dominant mode analysis fails to provide effective control actions when several modes have similar low damping ratios. This work addresses this problem by considering all modes in the formulation of the system kinetic oscillation energy. The integral of energy over time defines the total action as a measure of dynamic performance, and its sensitivity allows comparing the performance of different actuators/locations in the system to select the most effective one to damp the oscillation energy. Time domain simulations in the IEEE 9-bus system and IEEE 39-bus system verify the findings obtained by the oscillation energy based analysis. Applications of the proposed method in control and system planning are discussed.Comment: Conference paper, IEEE PESGM 201

Real-Time Area Angle Monitoring Using Synchrophasors: A Practical Framework and Utility Deployment

This article develops a practical framework of Area Angle Monitoring (AAM) to monitor in real time the stress of bulk power transfer across an area of a power transmission system. Area angle is calculated from synchrophasor measurements in real time to provide alert to system operators if the area angle exceeds pre-defined thresholds. This article proposes a general method to identify the warning threshold of area angle and a simplified method to quickly update area angle thresholds under significant topology change. A mitigation strategy to relieve the area stress is also proposed. In order to handle the limited coverage of synchrophasor measurements, this article proposes a method to estimate phase angles for boundary buses without synchrophasor measurements, which extends the application scenario of AAM. AAM is verified for a power transmission area in the Western Electricity Coordinating Council system with both simulated data and synchrophasor measurements recorded from real events. A utility deployment for real-time application of AAM with livestream and recorded synchrophasor data is described.This is a manuscript of an article published as Ju, Wenyun, Ian Dobson, Kenneth Martin, Kai Sun, Neeraj Nayak, Iknoor Singh, Horacio Silva-Saravia, Anthony Faris, Lin Zhang, and Yajun Wang. "Real-Time Area Angle Monitoring Using Synchrophasors: A Practical Framework and Utility Deployment." IEEE Transactions on Smart Grid 12, no. 1 (2021): 859-870. DOI: 10.1109/TSG.2020.3020790. Posted with permission.</p