Mixed Integer Programming of Security-Constrained Daily Hydrothermal Generation Scheduling(SCDHGS)

Abstract

This paper presents the application of Mixed-Integer Programming (MIP) approach for solving the Daily Hydrothermal Generation Scheduling (DHGS). In restructured power systems; Independent System Operators (ISOs) execute the Security-Constrained Unit Commitment (SCUC) program to plan a secure and economical hourly generation schedule for the daily/weekly-ahead market. The DHGS is a highly dimensional mixed-integer optimization problem, which might be very difficult to solve when applied for realistic power system, therefore we use MIP. This approach allows precise modeling of hydro and thermal systems that are represented in high detail. It includes valve point loadings, prohibited operating zones (POZs), dynamic ramp rate limits, non-linear start-up cost functions of thermal units, variable fuel cost, operating services, fuel and emission limits of thermal units and variable head Water-to-Power conversion function of hydro plants. To assess the approach, a study case based on an IEEE 118 bus system is performed. The effectiveness of the proposed model is shown on different test systems.