A COORDINATED APPROACH FOR REAL-TIME SHORT-TERM HYDRO SCHEDULING

The paper describes a coordinated approach to short-term hydro schedul ing and dispatch that has been developed as a part of the Tasmanian Hy dro Electric Commission's (HEC) new Energy Management System (EMS), wh ich is being delivered by Landis and Gyr Energy Management, Tasmania's hydro generation system consists of 40 reservoirs in six river catchm ents, The daily water release for each plant is scheduled using the HE C's mid-term operation policy, The Hydro Scheduling and Commitment (HS C) function schedules the hydro units on a half hourly basis so that t he allocated water release maximizes the energy production. This maxim ization of energy production is achieved by maximizing the head and th is ensures that operation is always as close as possible to maximum ef ficiency. Mixed Integer Linear Programming is used with detailed model of the interconnected hydro system to determine the half-hourly opera tion schedule, The Hydro Economic Dispatch (HED) function is used to i mplement the schedules produced by HSC in the real-time operation. The HED also uses a detailed model of the hydro system with a Linear Prog ramming algorithm to ensure that each unit operates as close as possib le to its head-dependent theoretical maximum efficiency point while me eting the desired storage levels specified by the HSC solution. HSC an d KED have been tested against a number of operational scenarios and w hen it is fully integrated within the new EMS it is expected to yield annual stored energy savings up to 0.5% through more efficient hydro-e lectric system operation. It is expected to also provide additional sa vings by fostering improvements to the mid-term operating plan.