Open AccessFrequency‐constrained unit‐commitment using analytical solutions for system frequency responses considering generator contingencies
Author(s) -
Rabbanifar Payam,
Amjady Nima
Publication year - 2020
Publication title -
iet generation, transmission and distribution
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.92
H-Index - 110
eISSN - 1751-8695
pISSN - 1751-8687
DOI - 10.1049/iet-gtd.2020.0097
Subject(s) - voltage droop , control theory (sociology) , electric power system , generator (circuit theory) , power system simulation , frequency deviation , frequency response , computer science , power (physics) , automatic frequency control , mathematical optimization , mathematics , engineering , telecommunications , voltage regulator , physics , control (management) , quantum mechanics , artificial intelligence , electrical engineering
The frequency responses of a power system following a generator outage are closely related to the commitment states of generators, which describe the droop and inertial characteristics and system pre‐contingency power dispatch. This study presents a new model to estimate the transient and steady state frequency responses of two‐area power systems at any moment following the loss of an online generator. In the proposed model, the deviations of tie‐flow, area frequencies and rate of change of area frequencies as well as the extreme values of these functions and their associated time of occurrence following the outage of a generation unit are derived as modified analytical functions. A new approach is also proposed to linearise the modified extreme deviations based on pseudo‐Boolean function theorem. In addition, a frequency‐constrained unit commitment model with modified frequency‐dependent constraints incorporating primary frequency regulation reserve is presented as a mixed‐integer linear programming problem. The results indicate that the proposed method gives acceptable approximations for post‐contingency responses and can ensure power system security from frequency viewpoint.