Project Details
Fundamentally new method for analysis and setting of protections for power systems with a large share of grid-connected converters
Applicant
Professor Dr. Willem Leterme
Subject Area
Electrical Energy Systems, Power Management, Power Electronics, Electrical Machines and Drives
Term
since 2024
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 542328356
The transition to a low-carbon economy requires a shift from fossil-fueled power plants to renewable energy sources, such as solar photovoltaic or offshore wind, as main source of electrical power. To enable this shift, the design and operation of the electric power system must undergo a radical transformation. In this project, we focus on power system protection against short-circuits and more in particular on a fundamental update for analysis and setting of protection functions that detect and identify faults. The correct operation of protection functions is critical for safely operating the power system, as to ensure continuity of power supply and avoid damage to components. Present literature has qualitatively shown that most of presently used protection functions malfunction in an electrical power system fed by renewable energy sources. The main cause for this loss of reliability are the short-circuit currents provided by power-electronic converters that connect renewable energy sources to the electrical power system. These converters provide short-circuit currents that are six to eight times lower and less predictable compared to those supplied by the rotating electrical machines associated with fossil-fueled power plants. Present methods that are used within the field of power system protection fail to quantify the loss of reliability and are not efficient for adapting protection functions to grids with a large share of grid-connected converters associated with renewable energy sources. The objective of this project is to fundamentally update power system protection theory, by developing a method for quantitative analysis and setting of protection functions which is accurate, computationally efficient and generally applicable. In previous research, we have shown that a mathematical rewriting of presently used indicators for quantifying protection performance enables to establish a link between power system protection and modern classification theory. For the first time, we introduced probabilistic models to analyze protection functions and applied Bayesian analysis and decision theory. Building upon this research, this project will develop new probabilistic models for various types of protection functions and develop efficient methods and performance indicators to evaluate these. The method to be developed shows potential not only for quantitative analysis of protection function performance, but also for protection function setting and design of new protection functions. It is intended for application to any type of electrical power systems, but will especially prove valuable in systems with a large share of renewable energy sources.
DFG Programme
Research Grants