Critical clearing time estimation of multi-machine power system transient stability using fuzzy logic

<span lang="EN-US">Studying network stability requires determining the best critical clearing time (CCT) for after fault has occurred. CCT is an essential issue transient assessment (TSA) in operation, security, and maintenance of electrical power system. This paper proposes algorithm to obtain based on fuzzy logic (FL) under conditions, a multi-machine was estimated using two-step algorithm: first step calculate Δt, which represents output FL, while maximum angle deviation (δmax) input. The second classify system if it stable or unstable system, two inputs mechanical input (Pm), average accelerations (Aav). results proposed method were compared with domain simulation (TDS) method. showed accuracy speed estimation FL method, error rate not exceeding 5%, reduced performance by about half time. approach tested both IEEE-9 bus IEEE-39 systems MATLAB.</span>