The effect of load uncertainty on unit commitment risk

This paper describes a method for analyzing the effect of load uncertainty on unit commitment risk, which is the probability of having insufficient committed capacity to compensate for unit failures and/or unanticipated load variation. This risk is evaluated using the usual Markov model for unit failures and a Gauss-Markov load model for load uncertainty. A rescheduling policy is essential for stochastic risk evaluation; thus one is described in this paper. The risk and the average operating reserve are evaluated using Monte Carlo simulation, and the Monte Carlo simulation is applied to the IEEE-RTS in order to demonstrate the effect of load uncertainty on the risk and on the average amount of required operating reserve. This paper is the first to combine a stochastic load model with the usual Markov unit failure model for unit commitment risk evaluation. >