G536 – ABB UnitrolTM Excitation System

G536 – ABB UnitrolTM Excitation System


ABB UnitrolTM Excitation System reliability and availability can be a matter of skilled routine maintenance activity and proficient troubleshooting capability. Proficient troubleshooting is greatly aided by a solid operational understanding of the excitation system. This course gives technicians and engineers the necessary knowledge to maintain, repair and calibrate the Unitrol Excitation System by:
  1. Using effective routine maintenance practices.
  2. Knowing what checks may be performed on-line and how to perform these checks without causing an equipment shutdown.
  3. Increasing the likelihood of accurate problem diagnosis by thoroughly understanding how the equipment operates.
  4. Increasing the likelihood of accurate problem diagnosis by understanding any given board's impact upon operations; ie., quickly linking the symptom(s) to the faulty board.
  5. Verifying a suspected faulty board by analyzing voltage levels and/or signal traces.
  6. Understanding the necessary calibrations, after the faulty part has been replaced, including how the calibrations are performed.
HPC's Excitation System course makes heavy use of prints, on which the participants are encouraged to take notes. This provides a valuable reference for future use. In addition, the student manuals contain a complete description of the excitation system operation. This course is intended for electrical technicians and engineers


Upon completion of this course, participants will be able to:
  1. Discuss how an excitation system accomplishes voltage and VAR control.
  2. Discuss the primary and secondary roles of an excitation system.
  3. Discuss the major excitation system components, including limit and protective features.
  4. Discuss the Discuss the operation of each module found within the UnitrolTM Excitation System.
  5. With the use of prints, trace a given signal change through the excitation system.
  6. Discuss routine maintenance including what can and cannot be done on-line.
  7. Discuss troubleshooting of the Excitation System, including expected voltage/signal levels.
  8. For a given symptom, list the most probable fault location(s).
  9. Discuss the options available to quickly narrow down the fault location.
  10. Discuss the necessary calibration, for each board, following board replacement

Course Outline

  1. Excitation System Fundamentals
  2. AC Generators
  3. General Excitation System Description - System Purpose and Overview
  4. Major Components : Pilot Generator, Automatic Voltage Regulator, Manual Voltage Regulator, Stationary Uncontrolled Rectifier, Stator Current Regulator, Excitation Current Regulator, Rotor Angle/Load Angle Limiter, Field Breaker and Discharge Resistor, Follow Up Controller, Power Stage and Grid Contro
  5. Routine Maintenance
  6. Troubleshooting & Repair: Six-step Troubleshooting Method, Symptom Analysis, Expected Voltage/Signal Levels, Most Common Failures, Post Replacement Calibration

Course Dates / Location / Fee

On-Site Only

What you will receive

  1. 1 copy of HPC Technical Services' textbook, (ABB) UnitrolTMVoltage Regulator
  2. A "Certificate of Completion" with PDH

Frequently Asked Questions

  • Will HPC Technical Services bring this course to our location for our personnel only? YES, call or email Stephen Parker, Stephen@TurbineGeneratorTraining.com for a price quotation.
  • Will HPC Technical Services customize the presentation at our site to suit our particular needs?
  • Is HPC Technical Services' textbook available for purchase as a reference document? No, this book is not for sale as the course is too dependent upon print reading.
  • What is the cost for HPC Technical Service to deliver this course at our location? Well, of course that can vary, but generally speaking, if you're planning on having 6+ attend, when considering your T&L, it is to your advantage to perform the course at your plant (office).  You gain from the customization and price.
  • Can HPC Technical Services provide "Technical Assistance" in the maintenance troubleshooting of your excitation system? Yes we can.  Call or contact Stephen Parker, Stephen@TurbineGeneratorTraining.com for our rate sheets and any further information required.

Generator I&c Certification

Those who attend this course are automatically qualified to take HPC Technical Services' Certification Examination.  This examination is offered at no additional expense to the participant.  An 80% passing grade is required.  The examination length will not exceed 2-hours.  Those who complete this examination will receive a revised "certificate of completion" that recognizes this accomplishment along with two-copies of a "To Whom It May Concern" letter that states their accomplishment.  (Two copies are provided, one for the participants' employer and one for the participants' personal file.)  Consult HPC's website, www.TurbineGeneratorTraining.com, for detail on this certification program.