Pendeteksian Misalignment Menggunakan Multi Level Transformasi Wavelet Haar dan Coiflet pada Motor Induksi

Abstract

Currently induction motors are widely used in industry due to strong construction, high efficiency, and cheap maintenance. Machine maintenance is needed to prolong the life of the induction motor. As studied, bearing faults may account for 42% -50% of all motor failures. In general it is due to manufacturing faults, lack of lubrication, and installation errors. Misalignment of motor is one of the installation errors. This paper is concerned to simulation of discrete wavelet transform for identifying misalignment in induction motor. Modelling of motor operation is introduced in this paper as normal operation and two variations of misalignment. For this task, haar and coiflet discrete wavelet transform in first level until fifth level is used to extract vibration signal of motor into high frequency of signal. Then, energy signal and other signal extraction gotten from high frequency signal is evaluated to analysis condition of motor. The results show that haar discrete wavelet transform at thirth level can identify normal motor and misalignment motor conditions well

Studi Analisis Perbandingan Pwm Carrier Untuk Multilevel Inverter Tiga Fasa Lima Belas Level Dengan Sumber Input Simetris Terpisah

“…Pada metode POD PWM ini seluruh sinyal carrier memiliki frekuensi dan amplitude yang sama namun berbeda dengan sudut fasanya, dimana pada sisi setengah siklus positif gelombang sinyal referensi sudut fasa carrier sebesar 0 o sementara setengah siklus negative sudut fasa carrier memiliki sudut fasa 180 o [9] seperti ditunjukkan pada gambar 9 sementara gelombang pulsa pensaklarannya dapat dilihat pada gambar 10.…”

“…Pada metode CO PWM ini seluruh sinyal carrier memiliki frekuensi yang sama dan memiliki amplitude puncak ke puncak yang sama, sinyal carrier ditempatkan sedemikian rupa sehingga pita yang mereka dapatkan saling tumpang tindih sampai setengah dari amplitudonya, dan sinyal referensi dipusatkan di tengah sinyal carrier [9] seperti ditunjukkan pada gambar 11 sementara gelombang pulsa pensaklarannya ditunjukkan pada gambar 12.…”