Security Assessment in Future Power Systems

  • James Brooks

Student thesis: Doctoral ThesisPhD


The penetration of unscheduleable generation will increase due to legislation and eventually saving on fuel cost. This will cause an increase in uncertainty of power-flow and drive up balancing market costs, the safety margin for N-1 will have to increase. i.e. N-1 will not accurately represent the state of the system. A security assessment scheme (SAS) that considers probabilistic uncertainty could give financial savings and/or better security of supply.In other words a power system with a high penetration of renewables is likely to require a new type of security assessment scheme. Before that is done we must be able to compare and evaluate existing and proposed schemes.This thesis has two goals. Firstly, to be able to compare two security assessment schemes to determine which is better for the current system. The work details a computer program that combines a two stage Monte Carlo Sampler and a power system simulator to generate a level of security. The number of simulations that fail to converge within limits in N-1 and N-2 was compared to the calculated level of security and found to not be a good predictor.The second goal is to see how the level of security changes as the uncertainties of renewable generation get added into a given power system. In doing this, the effect of adding renewables can be quantified. The work found that if 15% of the generation power comes from generators the are unscheduleable or stochastic the security of supply does not greatly change. Whereas if the penetration is increased to 30% the security level become significantly worse in almost all tested scenarios.
Date of Award5 Oct 2013
Original languageEnglish
Awarding Institution
  • University of Bath
SupervisorRoderick Dunn (Supervisor)

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