Primary Frequency Response Reserve Products for Inverter-Based Resources

Primary frequency control in power systems is being challenged by the large-scale integration of inverter-based resources (IBRs) because they do not typically respond to frequency fluctuations. This paper suggests introducing new reserve products into the electricity market that provide incentive for IBRs to contribute to primary frequency control in ways that take advantage of their fast-acting capabilities. In addition to a Primary Frequency Response (PFR) reserve product, which accommodates standard droop control, we suggest introducing a Fast Frequency Response (FFR) reserve product, a reserve product for Virtual Inertia (VI), which is also known as synthetic inertia, and an inertia product. We adopt a reserve requirement that guarantees sufficient primary frequency response reserve to adequately arrest frequency decline in response to a large generator outage within a certain margin. We place this reserve requirement into a real-time co-optimization problem, derive prices for each product and analyze the incentives provided to IBRs

Voltage Control Performance Evaluation using Synchrophasor Data

With increasing availability of synchrophasor technology, enabled by phasor measurement units (PMUs), applications based on this technology are being implemented as a practical approach for power systems monitoring and control. While synchrophasor data provides significant advantages over SCADA data it has limitations, especially in the area of model validation and estimation. With the increasing complexity of the power system, the need for equipment monitoring and performance evaluation becomes more relevant, traditionally model validation and estimation process can be used to look at control equipment performance. However, due to the challenges associated with these processes there are limitations on the performance evaluation. This work introduces am improved signal-processing based algorithm to monitor control system performance during disturbance events in the power system and during ambient conditions, or normal power system operation, additionally the algorithm is demonstrated on data obtained from the interconnection point of a STATCOM device and a synchronous generator during ambient and disturbance operation

Effects of Wind Turbine Generators on Inter-Area Oscillations and Damping Control Design

This paper analyzes the effect of wind turbine integration (WT) on the inter-area oscillation mode of a test two-area power system. The paper uses a root-locus based design method to propose a pair of controllers to provide damping to the inter-area mode of the system. The controllers are selected from the best combination of feedback signal and WT control action. One of the controllers uses the active power control part of the WT while the other uses the reactive power part. The paper analyzes the impact that increases on the transmission line connecting the WT to the system have on the controllers’ performance. Time domain simulations are provided to evaluate the effectiveness of the controllers under different conditions

Identification of Linear Power System Models Using Probing Signals

This paper compares the accuracy of two methods to identify a linear representation of a power system: the traditional Eigensystem Realization Algorithm (ERA) and the Loewner Interpolation Method (LIM). ERA is based on time domain data obtained using exponential chirp probing signals and LIM system identification method is based on frequency domain data obtained using sinusoidal probing signals. The ERA and LIM methods are evaluated with the noise produced by the nonlinear characteristics of the system, these characteristics are caused by increasing the amplitude of the applied probing signal. The test systems used are: the two-area Kundur system and a reduced order representation of the Northeastern portion of the North American Eastern Interconnection. The results show that the LIM method provides a more accurate identification than the ERA method

Development and assessment of second generation WTG models in an open source platform

Currently, there is a substantial demand for mathematical models of wind power generators in power system simulation tools. This can be explained by two factors: (i) wind now contributes a significant part of the power produced in different power systems around the world; (ii) one requirement to design an intelligent renewable power infrastructure is to rely on accurate and open models to simulate the different components of an electric power system (EPS). This article presents the development and implementation of second-generation generic wind turbine generators (WTGs) models in the Power System Toolbox (PST)—open source software for power system transient simulation. The evaluation of these models is performed using simulation studies on two test systems: a single machine infinite bus (SMIB) system, and the IEEE 68-Bus system. Transient stability and small signal analysis are performed using Type-3 and Type-4 wind turbines models to assess the performance of such modelsCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPnão tem2016/08645-

Traveling Wave Energy Analysis of Faults on Power Distribution Systems

This paper explores the most important factors that define the Traveling Wave (TW) propagation on distribution systems. The factors considered in this work are: the distance to the fault location, the fault type, and the crossing of system elements (such as regulators, capacitor banks, laterals, and extra loads within the protection zones). This work uses a realistic, yet simplified, distribution system composed of two protection zones, in which, several combinations of the previously mentioned factors are considered. The simulated fault measurements undergo a signal processing stage in which, first, they are decomposed into independent modes using the Karrenbauer transform. Second, a time–frequency representation is obtained using the Stationary Wavelet Transform (SWT), dividing the signal into several frequency bands. Finally, the Parseval’s Energy (PE) theorem is applied to calculate the signal energy in each frequency band. A qualitative analysis is performed based on the previously calculated energies to outline which are the factors that most affect the TW energy during propagation. The results show that distance, the presence of regulators, either in the propagation path or upstream, and the type of fault are the main factors that affect TW propagation across the system, and therefore they should be considered for TW-based protection schemes for distribution systems

A Survey of Traveling Wave Protection Schemes in Electric Power Systems

As a result of the increase in penetration of inverter-based generation such as wind and solar, the dynamics of the grid are being modified. These modifications may threaten the stability of the power system since the dynamics of these devices are completely different from those of rotating generators. Protection schemes need to evolve with the changes in the grid to successfully deliver their objectives of maintaining safe and reliable grid operations. This paper explores the theory of traveling waves and how they can be used to enable fast protection mechanisms. It surveys a list of signal processing methods to extract information on power system signals following a disturbance. The paper also presents a literature review of traveling wave-based protection methods at the transmission and distribution levels of the grid and for AC and DC configurations. The paper then discusses simulations tools to help design and implement protection schemes. A discussion of the anticipated evolution of protection mechanisms with the challenges facing the grid is also presented