Module Details for the Academic Year 2018/2019

EEEN40340 Power System Stability

The module explains the mathematical background of the phenomena that lead to power system instability, studying numerical methods to tackle such phenomena. The module is divided into four parts.

Part I: long term voltage stability. Bifurcation theory (saddle-node, limit-induced and singularity-induced bifurcations) and the voltage collapse phenomenon. Continuation power flow analysis. Direct methods. Voltage stability constrained OPF. Voltage stability indexes. Cascade line tripping phenomenon.
Part II: large perturbation angle stability (transient stability). Lyapunov theory. Direct methods. Time domain analysis methods. Hybrid methods (e.g. SIME). Transient stability constrained OPF. Multi-swing phenomenon.
Part III: small-signal angle stability analysis. Hopf bifurcations and limit cycles. Monodromy matrix. Routes to chaos, Poincaré maps and Lyapunov exponents. Small-signal stability constrained OPF. Effect of delays and analytical methods to assess the stability of delayed DAEs.
Part IV: frequency stability. Load shedding problem. Frequency stability with renewable energy sources. Effect of thermostatically controlled loads.

Each part is completed by real-world examples (large scale blackouts), practical remedial actions and several computer-based simulation examples to support theoretical aspects.

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Basic principles of stability analysis of nonlinear differential-algebraic equation systems. Definitions, causes and concepts of voltage, transient, angle and frequency stability. Applied numerical methods to assess power system stability of large power systems. Practical control and protection strategies to avoid power system instabilities and blackouts.  
Item Workload




Autonomous Student Learning


Online Learning




Description % of Final Grade Timing
Examination: Examination


2 hour End of Semester Exam
Lab Report: Frequency stability analysis


Week 12
Lab Report: Numerical stability of power flow analysis


Week 4
Lab Report: Small-signal stability analysis


Week 8
Lab Report: Transient stability analysis


Week 10
Lab Report: Voltage stability analysis


Week 6
Presentation: Description and analysis of a blackout


Week 12


This module is passable by compensation

Resit Opportunities

End of Semester Exam


If you fail this module you may repeat, resit or substitute where permissible

Module Requisites and Incompatibles

Pre-Requisite: Electrical Machines (EEEN30090), Power system Engineering (EEEN30070)

Co-Requisite: Apps of Power Electronics (EEEN40120), Control Theory (EEEN40010)

Equivalent Modules

Prior Learning

Students taking this module must have a strong understanding of electrical power systems and control theory, and be fully conversant with the underlying mathematics.
Curricular information is subject to change