Power System Transient Stability Study Fundamentals - a PDH Online Course for Engineers, Surveyors and Architects

Power System Transient Stability Study Fundamentals

Course Outline

The ability of a power system, containing two or more synchronous machines, to continue to operate after a change occurs on the system is a measure of its stability. The stability problem takes two forms: steady-state and transient. Steady-state stability may be defined as the ability of a power system to maintain synchronism between machines within the system following relatively slow load changes. Transient stability is the ability of the system to remain in synchronism under transient conditions, i.e., faults, switching operations, etc. In an industrial power system, stability may involve the power company system and one or more in-plant generators or synchronous motors. Contingencies, such as load rejection, sudden loss of a generator or utility tie, starting of large motors or faults (and their duration), have a direct impact on system stability. Load-shedding schemes and critical fault-clearing times can be determined in order to select the proper settings for protective relays.

These types of studies are probably the single most complex ones done on a power system. A simulation will include synchronous generator models with their controls, i.e., voltage regulators, excitation systems, and governors. Motors are sometimes represented by their dynamic characteristics as are static var compensators and protective relays.

This course reviews the subject of transient stability calculations in a very structured fashion. First, modelling technique is shown for a generic power system, dynamic equipment is modelled in details and calculations are performed for selected disturbances throughout the system. A detailed explanation of modelling and calculation procedure is offered. Explained techniques can be implemented in any commercial power system software package.

This course includes a multiple choice quiz at the end, which is designed to enhance the understanding of the course materials.

Learning Objective

At the conclusion of this course, the student will:

Power system stability fundamentals;
Problems caused by instability;
System disturbances that can cause instability;
Solution to stability problems;
System stability analysis;
Stability studies for power systems; and
Example.

Intended Audience

This course is intended for electrical engineers.

Benefit to Attendees

Attendee of this course will understand power system stability fundamentals and what problems are caused by system instability. Also solutions to practical instability problems will be introduced and attendee will be able to complete overall system stability analysis.

Course Introduction

For years, system stability was a problem almost exclusively to electric utility engineers. Small independent power producers (IPPs) and co-generation (co-gen) companies were treated as part of the load and modelled casually. Today, the structure of the utility industry is going through a revolutionary change under the process of deregulation. A full-scale competition in the generation market is on the horizon. Increasing numbers of industrial and commercial facilities have installed local generation, large synchronous motors, or both.

The role of IPP/co-gen companies and other plants with on-site generation in maintaining system stability is a new area of interest in power system studies.
When a co-generation plant (which, in the context of this chapter, is used in reference to any facility containing large synchronous machinery) is connected to the transmission grid, it changes the system conﬁguration as well as the power ﬂow pattern. This may result in stability problems both in the plant and the supplying utility.

Course Content

In this lesson, you are required to download and study the following course content in PDF format:

Power System Transient Stability Study Fundamentals

Please click on the above underlined hypertext to view, download or print the document for your study. Because of the large file size, we recommend that you first save the file to your computer by right clicking the mouse and choosing "Save Target As ...", and then open the file in Adobe Acrobat Reader. If you still experience any difficulty in downloading or opening this file, you may need to close some applications or reboot your computer to free up some memory.

Course Summary

Power systems are highly nonlinear and the dynamic characteristic of a power system varies if the system loading, generation schedule, network interconnection, and/or type of system protection are changed. When a co-gen plant is connected to the utility grid, it changes the system conﬁguration and power ﬂow pattern in the utility. This may result in some unwanted system stability problems from low-frequency oscillations. The evaluation of potential problems and solution methods prior to the connection of the co-gen plant becomes a challenging task for the power engineer.

Quiz

Once you finish studying the above course content, you need to take a quiz to obtain the PDH credits.

DISCLAIMER: The materials contained in the online course are not intended as a representation or warranty on the part of PDH Center or any other person/organization named herein. The materials are for general information only. They are not a substitute for competent professional advice. Application of this information to a specific project should be reviewed by a registered architect and/or professional engineer/surveyor. Anyone making use of the information set forth herein does so at their own risk and assumes any and all resulting liability arising therefrom.