The paper presents a transmission-constrained unit commitment method using a Lagrangian relaxation approach. The transmission constraints are modeled as linear constraints based on a DC power flow model. The transmission constraints, as well as the demand and spinning reserve constraints, are relaxed by attaching Lagrange multipliers. The authors take a new approach in the algorithmic scheme. A three-phase algorithm is devised including dual optimization, a feasibility phase and unit decommitment. A test problem involving more than 2500 transmission lines and 2200 buses is tested along with other test problems

Meeting Name

31st Hawaii International Conference on System Sciences, 1998


Engineering Management and Systems Engineering

Keywords and Phrases

DC Power Flow Model; Lagrange Multipliers; Lagrangian Relaxation Approach; Buses; Demand Constraints; Dual Optimization; Economic Dispatch; Economics; Feasibility Phase; Integer Programming; Linear Constraints; Load Dispatching; Power System Analysis Computing; Power System Planning; Power Transmission Lines; Relaxation Theory; Scheduling; Spinning Reserve Constraints; Three-Phase Algorithm; Transmission Constraints; Transmission Lines; Transmission-Constrained Unit Commitment Method; Unit Decommitment

Document Type

Article - Conference proceedings

Document Version

Final Version

File Type





© 1998 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.