The development of the transformer insulation failure undergoes three stages: insulation aging, incipient faults and a short circuit. This paper presents a complete scheme to simulate single-phase transformers with insulation deterioration and arcing phenomena i.e. in the first two stages. The approach incorporates Transmission Line Methods (TLM), Jiles-Atherton Hysteretic Model, Composite Cass...

The development of the transformer insulation failure undergoes three stages: insulation aging, incipient faults and a short circuit. This paper presents a complete scheme to simulate single-phase transformers with insulation deterioration and arcing phenomena i.e. in the first two stages. The approach incorporates Transmission Line Methods (TLM), Jiles-Atherton Hysteretic Model, Composite Cass...

Continuous monitoring of Power transformer is very much essential during its operation. Incipient faults inside the tank and winding insulation needs careful attention. Traditional ratio methods and Duval triangle can be employed to diagnose the incipient faults. Many times correct diagnosis due to the borderline problems and the existence of multiple faults may not be possible. Artificial inte...

Abstract: Since incipient faults often have small amplitudes and obscure symptoms, those observer-based or output residual-based fault indicators are ineffective for incipient faults, especially in the presence of system disturbances. The ToMFIR-based fault detection approaches use both controller and output residuals to construct a fault indicator, which make them sensitive to incipient faults...

This paper presents the characterization of transients resulting from faults in transformers using discrete wavelet transform (DWT). This characterization will aid in the development of an automatic detection method for internal incipient faults in the transformers. The detection method can provide information to predict failures ahead of time so that the necessary corrective actions are taken ...

Because of the development of electric power industry accurate analysis of incipient faults in generators becomes very important. This paper presents a method for simulating the internal faults in synchronous generators using artificial intelligence technique. The internal faults like single line to ground, double line to ground & triple line to ground of generator stator current, rotor speed, ...

tree analysis is widely used in industry for fault diagnosis. The diagnosis of incipient or 'soft' faults is considerably more difficult than that of 'hard' faults, which is the case considered normally. A detailed fault tree model reflecting signal variations over a wide range is required in the case of soft faults. This paper presents comprehensive results describing the diagnosis of incipien...

In this article we propose a combined signed directed graph (SDG) and qualitative trend analysis (QTA) framework for incipient fault diagnosis. The SDG is the rst level in our framework and provides a possible candidate set of faults based on the incipient response of the process. The search for the actual fault is performed based on a QTA, which uses the temporal evolution of the sensors for f...

Faults and damage in oil-filled power transformers has a devastating effect on the overall reliability of electrical power systems. Several factors, especially electrical and thermal stresses age the transformer and subject them to incipient faults. These faults, if left undetected will cause deterioration and eventually lead to failure of the transformer [1]. The presence of faults such as arc...

Detection of incipient (slowly developing) faults is crucial in automated maintenance problems where early detection of worn equipment is required. In this paper, a general framework for model-based fault detection and diagnosis of a class of incipient faults is developed. The changes in the system dynamics due to the fault are modeled as nonlinear functions of the state and input variables, wh...