Marginal Unit Generation Sensitivity and its Applications in Transmission Congestion Prediction and LMP Calculation


Conventional optimization technique suggests that marginal unit generation sensitivity (MUGS) may be calculated based on perturbation at optimality. The calculated MUGS however only applies to the perturbed operating point. Often times it is not advisable to apply this local information to predict generations at another loading level with considerable load change, and therefore another calculation has to be performed to obtain the generation and its sensitivity at that loading level. It is of high interest to obtain a global pattern of the sensitivity in a wider range of loading levels, which bears great potential in applications such as congestion prediction and LMP calculation. Existing work have shown MUGS can be well approximated by a linear function of load. In this paper, explicit formulations are derived for some special cases and show that MUGS is precisely a linear function or constant in those cases. The usefulness of MUGS is demonstrated with two applications, congestion prediction and LMP (sensitivity) calculation. Based on MUGS, optimal load shift factor (OLSF) is proposed to facilitate predicting future binding constraints such as transmission congestions. As a function of MUGS, LMP and its sensitivity can be easily obtained.

Meeting Name

2011 IEEE/PES Power Systems Conference and Exposition, PSCE 2011 (2011: Mar. 20-23, Phoenix, AZ)


Electrical and Computer Engineering

Keywords and Phrases

Congestion Management; DCOPF; Energy Markets; Generation Sensitivity; Locational Marginal Pricing; Marginal Units; Optimal Power Flows; Power Markets; Transmission Planning; Electric Load Flow; Electric Power Transmission; Forecasting; Loading; Optimization; Power Transmission; Sensitivity Analysis; Locational Marginal Pricing (LMP); Marginal Unit; Optimal Power Flow (OPF)

International Standard Book Number (ISBN)


Document Type

Article - Conference proceedings

Document Version


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© 2011 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 Mar 2011