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Equipment malfunction in electric power plant may lead to catastrophic losses which can lead to significant economic losses, as well as harm to the reputation of the utility who is operating the power plant. Therefore, it is desirable to detect anomalous behavior in equipment, that in the future, might lead to damage or failure of that or other connected equipment. Equipment damage can increase operations...
This paper describes a model free method for monitoring and fault diagnosis of the elements in a rotor system for a wind turbine. The diagnosis as well as the monitoring is done without using any model of the wind turbine and the applied controller or a description of the wind profile. The method is based on available standard sensors on wind turbines. The method can be used both on-line as well as...
A new fault diagnosis scheme based on the monitoring of main air gap flux of the three phase squirrel cage induction motor is proposed. Most of the existing electrical techniques of condition monitoring are based on the stator current and/or leakage flux measurement outside the motor. Besides, most of these methods only concentrate on the time harmonics analysis of the acquired signal. We propose...
For the mechanical parts of helicopter easily damaged and often inducing accident, the key system to ensure flight safety of helicopter and achieve the on-condition maintenance is HUMS. In the paper the key technologies of HUMS are researched including position optimizing of the sensors, flight safety monitoring and diagnosing technology, the method of setting threshold, and it is dissertated in detail...
A new fault diagnosis scheme based on the monitoring of main air gap flux of squirrel cage induction motors is proposed. Most of the existing flux monitoring techniques are based on the leakage or stray flux measurement outside of the motor. A few methods, however, use the main air gap flux as the fault signature, where search coils are used to monitor the derivative of the flux, which eventually...
This paper presents a new approach of an integrated distributed monitoring system for an autonomous unmanned helicopter. The navigation mission consists of reaching areas of interest on a path composed of specific waypoints. The task of such a monitoring system is to determine whether the helicopter behaves as intended in order to detect faults in the mission execution early and to enable a re-planning...
Harmonic analysis of motor current has been used to track the speed of motors for sensorless control. Algorithms exist that track the speed of a motor given a dedicated stator current measurement, for example. Harmonic analysis has also been applied for diagnostic detection of electro-mechanical faults such as damaged bearings and rotor eccentricity. This paper demonstrates the utility of harmonic...
Large low speed hydro-generators (Fig. 1) have a very small specific air-gap to stator bore diameter ratio making it virtually impossible to have a perfect centering of the rotor within the stator during the assembly process. Therefore the machines are operated with an eccentricity that, though small, is not negligible, and is the cause of undesirable effects: considerable unbalanced magnetic pulls,...
A diagnostic strategy for the monitoring of the transmission properties and sparking of doubly-fed induction generators with slip rings is introduced in this paper. Modifications in the transmission properties can be recognized by measurement and evaluation of the rotor currents without additional sensors. The existing current transformers in the system can be used for the diagnostic
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