Sensitivity analysis of an optimal short term hydro-thermal schedule

The authors deal with the sensitivity analysis of an optimal short term hydro-thermal schedule. Methodological and practical aspects of the system economy loss (SEL) calculation caused by incorrect input data are investigated. It was shown and checked by numerical simulations that errors in the hydro plant characteristics can be studied through errors in the short term load forecasting. In a special case when differentiability conditions are satisfied (economic dispatching problem) analytical formulas for the SEL are developed. Some of the important results of sensitivity calculations concerning relevant errors in thermal cost coefficients, hydro plant characteristics, forecasted water inflows and forecasted system demands are presented. The critical input data have been selected and their tolerance margins established to preserve the beneficial effects of an optimal short term schedule.