Power Systems Technology

Learning Outcomes

Subject Specific Practical Skills

Having successfully completed this module you will be able to:

• Use the concept of symmetrical components in analysis, solve typical problems associated with faults, apply the notation of per unit system, interpret results from power system analysis

Knowledge and Understanding

Having successfully completed this module, you will be able to demonstrate knowledge and understanding of:

• Fundamental concepts of operation of electrical power systems; representation of various components of the system; theory of balanced and unbalanced faults; basic concepts of stability; control of power, frequency, voltage and VAr flows; simple methods for modelling and simulation of power systems

Transferable and Generic Skills

Having successfully completed this module you will be able to:

• Apply modern modelling techniques, tackle problems of interdisciplinary nature

Subject Specific Intellectual and Research Skills

Having successfully completed this module you will be able to:

• Appreciate the complexity of operation power systems, analyse simple cases of power system stability, identify some elements of automatic control in power systems, benefit from application of per unit system

The physical nature of large interconnected systems.

• The evolution of electrical power systems, the integration and interconnection of the transmission system, the various voltage and current levels.

Introduction to power system analysis.

• Balanced three-phase systems, phasors, calculations in the phasor domain, equivalent line-to-neutral diagrams, complex impedance, star-delta transformation, real, reactive, apparent and complex power, power factor, power in single-phase circuits, power in three-phase circuits.

Relationship between voltage reactive power, power and transmission angle.

• Importers and exporters or positive and negative VArs, power flow between active and passive units, derivation of transmission equation.

Representation of parameters of rotating machines, transformers, lines, cables, switchgear and loads.

• Equivalent circuits, their simplification and justification but also limitations on use, system representation for various conditions.

Per unit system and symmetrical components.

• Review of per unit system and its use, the choice of base quantities for per unit calculations, review of symmetrical component theory and derivation, both graphical and matrix.

Solution of systems with balanced and unbalanced faults.

• Simple fault analysis of single line to ground, double line to ground, line to line and three phase to ground with fault impedances, all using sequence diagrams; the introduction to transformer connections into fault calculations; basic three phase short circuit on a machine; brief review of sub-transient, transient and synchronous reactance and their physical origins; brief introduction to how computer methods are applied.

Control of power and frequency in interconnected systems.

• Governor characteristic and equations; calculation of power sharing; normal methods of frequency control.

Control of voltage and VAr flows.

• AVR response and VAr generation, static VAr compensators, injection of reactive power, tap-changing transformers; power factor correction, calculation of voltage profile and effect on VAr flow.

Stability.

• Definition, types of stability studies, automatic control of synchronous generators, limitation of magnitude of power transmittable, steady state stability, transient stability, swing equation, equal area criterion, effects of type of fault on stability, multi-machine studies, methods for improving.

Summative

This is how we’ll formally assess what you have learned in this module.

Referral

This is how we’ll assess you if you don’t meet the criteria to pass this module.

Repeat

An internal repeat is where you take all of your modules again, including any you passed. An external repeat is where you only re-take the modules you failed.