Comparison of Open and Short-Circuit Switches Faults Voltage Source Inverter (VSI) Analysis Using Time-Frequency Distributions

Abstract

Voltage source inverter (VSI) plays an important roles in electrical drive systems. Consistently, expose to hash environmental condition, the lifespan of the electronic component such as insulated-gate bipolar transistor (IGBT) may shorten and many faults related to the inverter especially switches can be occur. The present of VSI switches faults causing equipment failure and increased the cost of manufacturing process. Therefore, faults detection analysis is mandatory to identify the VSI switches faults. This paper presents the analysis of VSI switches faults using time-frequency distributions (TFDs) which are short times Fourier transform (STFT) and spectrogram. From time-frequency representation (TFR) obtained by using the TFDs, parameters of the faults signal are estimated such as instantaneous of average, root mean square (RMS), fundamental, Total Waveform Distortion (TWD), Total Harmonics Distortion (THD) and Total non-Harmonic Distortion (TnHD) of current signals. Then, based on the characteristics of the faults calculated from the signal parameters, VSI switches faults can be detected and identified. The performance of TFD for the faults analysis is also demonstrated to obtain the best TFD for switches faults detection and identification system. The results show that, STFT is the best technique to classify and identify VSI switches faults and can be implemented for automated system.

Accurate harmonic source identification using S-transform

“…Total harmonic distortion, THD, is used to measure of how much harmonic content in a waveform [40]. The instantaneous total harmonic distortion of a waveform is defined mathematically as (4),…”

An Accurate Classification Method of Harmonic Signals in Power Distribution System by Utilising S-Transform

“…Instantaneous RMS Fundamental Voltage: Instantaneous Total Nonharmonic Distortion: (8) Where P x (t, f) is the TFR of a signal, f 0 is the fundamental frequency, f s is sampling frequency, V 1rms(t) is instantaneous RMS fundamental voltage, V rms(t) is instantaneous RMS voltage and V h,rms (t) is RMS harmonic voltage. f hi =f 0 +25Hz, f lo =f 0 -25Hz, 25 Hz is chosen for f hi and f lo , it can represent the fundamental frequency value and use for calculating the value of the frequency element.…”

“…ST is a hybrid of STFT and WT, and can be utilized to characterize the harmonic components [5]. The benefit of ST gives a great multiresolution analysis while characterizing the harmonic components [6][7][8]. …”

An Improved Detection and Classification Technique of Harmonic Signals in Power Distribution by Utilizing Spectrogram

“…Time-frequency distributions are great techniques that represent a signal in, jointly, time and frequency representation as known as time-frequency representation (TFR). From TFR, spectral information of a signal can be observed with changes of time [8]. Therefore, the TFD are very applicable to analyse power quality signals that consist of non-stationary and multi-frequency components signal.…”