07 verification of fault condition behaviour of synch 2-pole generator using flux 2d w-doorsamy uni...

7/30/2019 07 Verification of Fault Condition Behaviour of Synch 2-Pole Generator Using Flux 2D W-Doorsamy UNI Witwatersrand

1/31

Flux Conference 2012

Verification of fault condition behaviour of asynchronous 2-pole generator using Flux 2-Dfinite element analysis software

W. Doorsamy

University of the WitwatersrandDate : 18 October 2012


2/31

Verification of fault condition behaviour of a synchronous 2-pole generator

2012 Flux Conference - Rome, Italy, October 17-18, 20122

Overview

Introduction

Background

Methodology

Experimental Setup

Flux Model

Fault Conditioning

Measurement

Results

Conclusion


3/31



Introduction

Increased load demands

Alternative methods of energy generation/ sources as a solution

Integrity of current generation systems have to be increased

Need for simple, reliable and cost effective condition monitoring


4/31



Introduction


5/31

Background

Online and offline methods of conditioning monitoring

Fault diagnosis accomplished through various methods:

Chemical

Mechanical

Electrical

5




6/31

Background

Diagnosis of incipient faults is essential prevention of extended

downtime and even catastrophic failure

Current methods utilise symptoms of damage/deterioration

Unacceptable

Previous work conducted on use of shaft signals for fault

diagnosis

6




7/31

Methodology

Consolidation of previous work conducted on fault diagnosis

Identification of exact effects of faults on shaft and flux probe

Simulation of fault conditions Experimental testing

Validation

Extend to use in multiple fault diagnosis

7




8/31

Experimental Setup

Miniature Generator designed to mimic large turbo-generators

Some Capabilities of Generator

20 kVA, 2 Pole, 340 V (line)

Cylindrical Rotor Core

Insulated Bearings

Open stator slots

8




9/31

Experimental Setup

Mini-Gen designed with additional features

Access to stator and rotor windings

Outboard slip rings for static excitation

Finished landings on shaft for use of specialised brushes

Stator position relative to rotor may be manipulated

Flux probes/search coils at various angular positions

9




10/31

Experimental Setup

10




11/31

Experimental

Setup

Three Phase

Rectifier

Mini-Gen

Shaft Brushes

Induction Motor(Prime Mover)

11




12/31

Flux Model

Casing

Stator

Slots

Air Gap

Rotor Core

Rotor Slots

12




13/31

Flux Model



13


14/31

Fault Conditioning

Incipient faults to analyse

3 Rectifier

Excitation winding short-circuit

Static Eccentricity

14




15/31

Fault Conditioning Rectifier Fault

15




16/31

Fault Conditioning Rectifier Fault

16




17/31

Fault Conditioning Rotor Short



17


18/31




18


19/31


19




20/31

Fault Conditioning Eccentricity

20




21/31

Fault Conditioning Eccentricity

21




22/31

Measurement

22



Probe

Brushes


23/31

Measurement

23



Flux probe connector Shaft brush insert


24/31

Results

24



% Changetends toinfinity due to

normalcondition 6th

harmonic 0


25/31

Results Rectifier Fault

25



Flux Probe


26/31

Results Rectifier Fault

26



ConditionHarmonic

(Hz)

Simulation Measurement

Percentage Change (%)

No Load200 657.10 94.00

250 43.99 38.24

With Load200 95.04 140.11

250 51.83 124.17

Shaft Brushes


27/31

Results Eccentricity

Reasons for large harmonic change (Simulation)

Simulation baseline (without fault) value at 300 Hz 0, therefore

% change

Real machine baseline (without fault) value has asymmetries

(imperfections)

Presence of noise

Sensitivity of simulation i.e. no observation effects unlike with real

setup



27


28/31

Results Fault Diagnosis System

28




29/31

Conclusion

Reasons for large harmonic change (expected)

Simulation predict behaviour and optimise experiment

Experimental results validate simulation predictions

Algorithm -> viable



29


30/31

Acknowledgements

EIE - University of the Witwatersrand

Professor W. A. Cronje

National Research Foundation

Cedrat



30


31/31

Thank you



07 verification of fault condition behaviour of synch 2-pole generator using flux 2d w-doorsamy uni...

Documents