Pertimbangan tentang kestabilan memainkan peranan yang penting dalam
perancangan sistem kuasa masa kini. Masalah kestabilan biasanya ditakrif mengikut
keadaan operasi yang berbeza. Walau bagaimana pun, masalah kestabilan yang kerap
timbul ialah kestabilan fana. Kestabilan fana, fokus utama dalam tesis ini, melibatkan
gangguan utama secara tiba-tiba, seperti berlakunya kerosakan, operasi penukaran talian
atau perubahan beban dengan tiba-tiba. Objektif tentang kajian kestabilan fana adalah
untuk menentukan sama ada sistem ini boleh menghadapi keadaan fana apabila
tertakluk kepada gangguan yang besar atau tidak. Oleh itu, tiga kaedah iaitu kaedah
Langkah Demi Langkah (step by step), kaedah Modified Euler dan kaedah Kriteria
Sama Luas (equal area criterion) digunakan untuk menganalisis kestabilan fana bagi
sistem kuasa dalam tesis ini. Beberapa program MATLAB telah direka untuk membuat
kajian tentang kestabilan fana bagi suatu mesin yang disambungkan kepada bas infiniti
dengan menggunakan tiga kaedah ini. Program-program ini berguna terutamanya dalam
menentukan waktu pemutusan kritis (critical clearing angle) untuk pemutus litar, sudut
pemutusan kritis (critical clearing time), sudut operasi baru (new operating angle), sudut
ayunan maksimum (maximum angle swing) bagi rotor serta tahap maksimum kuasa
elektrik yang dipindahkan. Selain itu, lengkung ayunan dan lengkung sudut daya
dipaparkan. Analisis ini membolehkan jurutera sistem kuasa untuk menentukan masa
operasi geganti dan pemutus litar supaya reliabiliti dalam sistem kuasa dapat dipastikan.
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Stability consideration plays an important part of power system planning today.
Stability problems are broadly defined according to different operating conditions.
However, frequent considered stability problems are transient stability. Transient
stability, the main focus of this thesis, involves sudden and major disturbances, such as
occurrence of fault, line switching operation or sudden load changes. The objective of
transient stability study is to determine whether or not the system can withstand transient
conditions subjected to large disturbance. Hence, three methods namely step
by step method, modified Euler’s method and equal area criterion method are used to
analyze the power system transient stability in this thesis. MATLAB programs are
developed in order to conduct case studies in transient stability for one machine
connected to infinite bus system by using these three methods. These programs are
useful especially in determining the critical clearing time for circuit breaker, critical
clearing angle, new operating angle, maximum angle swing of rotor as well as the
maximum electrical power transferred. Besides, the swing curve, in other words,
solution of rotor angle with respect to time and power angle curves are displayed. This
analysis enables power system engineers to design the operating times of the relay and
circuit breaker in order to ensure the reliability of the power system.