Dalam tempoh masa kebelakangan ini, topik kualiti kuasa elektrik telah menjadi isu utama di pihak utiliti dan pengguna itu sendiri. Masalah besar dalam kualiti kuasa ialah kejatuhan nilai voltan dan pengeherotan harmonik, disebabkan oleh beban tidak linear. Hal ini kerana kebanyakan beban – beban elektrik sekarang ialah beban yang berkapasiti tinggi seperti motor induksi tiga fasa, dan beban yang bersifat elektronik. Kehadiran masaalah kualiti kuasa ini boleh mengundang pelbagai masalah kepada pihak utiliti dan pengguna itu sendiri. Oleh itu badan – badan antarabangsa (IEC, IEEE) telah mewujudkan dan menetapkan satu piawaian dalam menangani dan mengawal masaalah pencemaran kualiti kuasa pada masa sekarang.
Ekoran dari permasaalah ini, satu kajian mengenai kualiti kuasa di kawasan pembahagian voltan rendah telah dijalankan untuk mengetahui dan memahami dengan lebih lanjut lagi tentang permasaalah ini. Fenomena kejatuhan sementara voltan, kesan pengherotan harmonik pada kehilangan kuasa dan faktor kuasa di kawasan pembahagian telah dimasukkan kedalam skop kajian. Selain itu, kesan daripada ketidak seimbangan
xi
beban pada sistem pembahagian 3 fasa empat wayar terhadap arus neutral juga disertakan di dalam kajian ini.
Untuk lebih memahami permasaalahan kualiti kuasa dengan lebih mendalam, satu lawatan dan pengukuran telah dilakukan di Pusat Pengajian Kejuruteraan Elektrik dan Elektronik dan Pusat Pengajian Kejuruteraan Mekanik telah dijalankan. Mengambil kira beban – beban yang terdapat di pusat pengajian tersebut, satu pengukuran terhadap paras harmonik telah dijalankan.
_____________________________________________________________________________________
In recent years, power quality has become a prolific buzzword and becomes the main issues on utility and customer side. The major problems in power quality are voltage sags and harmonic distortion, cause by a large capacity load and non – linear load. Recently, most of the electrical loads are on electronic based equipment and large capacity load. These problems could lead to another problem to utility and customer as well. Therefore, international organizations (IEC, IEEE) had created and stated a guidance and limitation in order to reduce and prevent the power quality problem nowadays.
Regarding that problem, a study about power quality in low voltage distribution network has been carried out in order to get more understanding about that particular matter. Voltage sag phenomena, effect of harmonic on power loss and power factor on power distribution been included in the study. Besides, effect of unbalance load on three phase four wire distribution system on neutral current is also investigated. In order to get more understanding about power quality, a site survey and monitoring also been carried out at School of Electrical and Electronic Engineering and School of Mechanical Engineering. Considering the type of loads at that particular site, a measurement on harmonic content been carried out.In order to get more understanding about power quality, a site survey and monitoring also been carried out at School of Electrical and Electronic Engineering and School of Mechanical Engineering. Considering the type of loads at that particular site, a measurement on harmonic content been carried out.