POWER ENGINEERS SUPPORTING TRUTH



Print this page

Table of Contents

Review Required of Electric Power System Operations

Prepared by F. J. Delea, J. A. Casazza, G.C. Loehr and R.M. Maliszewski

Power Engineers Supporting Truth

 

 

Electric power system reliability is the result of the effective interaction of institutions, numerous technological systems and operators.

  • Each of the institutions has its policies and requirements for the implementation of those policies,
  • Each of the technologies has its own characteristics and capabilities.  Included are different types of generation, power lines including terminal equipment,  power line protection, systems to monitor system status, metering of system information, data transmittal, computers and software, voice and data communications, control capabilities, etc.
  • Each of the operators has to work based on the training he has received in the environment determined by the institutions and the technologies available to him.

 

The increasing complexity of the operational requirements of the electric power system demands a thorough review of the role of each of these components and their impacts on reliability of the entire operating environment.  The investigation must determine if the operator has the authority, instructions, information, training, tools and capability to operate the system in a reliable state and to respond to system incidents in a timely and effective manner.  If not, the investigators must identify what has to be done to achieve the desired capabilities and times.  They also must establish a system to monitor and ensure that the capabilities are achieved and maintained.

 

The recommendations made to date in response to the request for comments on the draft report on the August 2003 blackout are a series of “Band Aids” in that they do not address the broader operating issue; i.e. in a significantly more complex operating environment, what exactly do we want our systems and our operators to accomplish? 

 

We recommend that teams of experienced operators and engineers define the overall requirements needed to operate a reliable power system.  The recommended investigation requires that the industry clearly and specifically state its mission, goals and objectives with regard to reliability.  The team should identify the full range of issues that can affect the reliable operation of a power system.  Once identified, the relative contribution of each issue to the reliable operation of the power system can be accessed and dealt with.  This investigation should also cover the operational relationship between the operating center and the RTO/ISO.

 

As an illustration of the complexity of just one of the issues involved, the Appendix to this document contains a listing of some, but not all, of the questions that could be asked when evaluating the system operator’s role and responsibility.  This material is not intended to be a thorough list of all the questions that need to be considered.  Another of the issues that should be examined in detail is the adequacy, in terms of numbers and skills, of the support staff at the operating center.

 

What we have to date is a scattered set of recommendations addressing parts of the issues impacting system operation but nothing that looks at the issues in a broad context.  Nothing tells us if we will achieve a set of overall objectives.  All relevant components of the operating environment (institutions, technological systems and operators) should be examined by groups of experienced operators and engineers to see if they contribute to meeting reliability objectives.  If not, recommendations should be made as needed for improvements.  If, after due deliberation, reliability goals cannot be achieved by normal means, different strategies may need to be developed; under no circumstance, however, should reliability standards be watered down.

 


 

Review Required of Electric Power System Operations

Appendix

 

 

As an illustrative example, consider a few, but not all, of the issues that could be addressed when evaluating whether a system control center/operator can meet the requirement to adjust power flows power flows following a contingency within a specified time period so as to be able to survive another contingency. 

 

  • How does an operator know a contingency has occurred?
  • How is the information presented to him?
  • How long does it take him to receive and digest the information?
  • How reliable and accurate is the information?
  • Does the operator need confirmation that the information is correct?
  • Does he know the full impact of the contingency - all lines and generators out of service, all line flows and voltages?
  • Does he have to request an impact analysis indicating to him the severity of the outage or is it done automatically for him?
  • Does the analysis consider all relevant issues; thermal line loadings, voltage and stability limits?
  • How good is the data about the system needed for the analysis, i.e. generators and transmission lines in service, their ratings/capabilities, the line impedances, the generator impedances, time constants etc?
  • Are there sufficient personnel, both operating and support, at the control center to ensure reliable operation?
  • What reliability criteria are being used?
  • When power flows, voltages, or other system conditions are found to be beyond the range of the specified criteria, how much time is permitted to get system conditions within appropriate limits?
  • Does the operator have the necessary human or computer help analyzing the situation or is he on his own?
  • Is the operator able to devote his full attention to analyzing the situation or are there distractions that interrupt him? 
  • What are his corrective action options?
  • How does he know them?
  • Are the options fully capable of doing what they are supposed to do? 
  • Which one(s) does he select?
  • How does he make this determination?
  • What tools does he have to help him decide on what to do?
  • How long does it take him to decide?
  • Does he have the authority to take all required actions?
  • If not, who does he have to contact for permission?
  • Is he trained to take the actions?
  • How current and adequate is his training?
  • What tools/capabilities does he have to implement the actions?
  • Are these tools/capabilities sufficient?
  • Do these tools/capabilities require actions by others?
  • Do those individuals who must implement corrective actions know of and acknowledge the authority of the operator
  • How quickly can these tools/capabilities be implemented (i.e. does he have to make phone calls to individual generating units, can he shed load from his control room or does he have to call field operators?
  • If not sufficient, what does he do?
  • If not fast enough, what does he do?

HOME

To participate in Pest activities contact:

 Jack Casazza
www.pest-o3.org
(703) 569-2543