Tie-Line Constrained Multi-Area Generation Scheduling Using Mixed Integer Programming Part II: Results and Discussion

Abstract

This paper is the part II of the two parts research papers. The objective of this work is to obtain an appropriate generation schedule satisfying system constraints and unit operation constraints with effective spinning reserve without tie-line congestion problem. The hybrid mixed integer programming process includes mixed-integer linear programming and quadratic programming (MILP-QP) is used to find the feasible solutions with total cost minimization while satisfying all important constraints. MILP is used to find generation schedule whereas QP is used to perform economic dispatch. It is tested on a ten unit system in three cases with 1, 2 and 3 areas linking with tie lines under DGS (Decentralized Generation Scheduling) and CGS (Centralized Generation Scheduling). Numerical results show that MILP-QP with DC line flow and virtual load constraints could provide feasible solutions effectively. Without virtual load constraints, line congestions may occur due to unforeseen higher load demand in next few minutes.