Power Quality Disturbance Monitoring and Classification Based on Improved PCA and Convolution Neural Network for Wind-Grid Distribution Systems
Abstract
:1. Introduction
2. Proposed Method for Feature Extraction and Classification
2.1. Improved Principal Component Analysis
Improved Principal Component Analysis Algorithm
2.2. Convolutional Neural Network (CNN)
2.2.1. Architecture of 1-D-CNN
2.2.2. Backpropagation
3. Feature Extraction by IPCA, 1-D-CNN and Statistical Analysis
4. Proposed Algorithm
5. Experiments
5.1. Generation of PQ Disturbances
5.1.1. Modified IEEE 13 Node Distribution Network
5.1.2. Synthetic PQ Disturbances
5.2. Dataset Generation
6. Results and Discussion
6.1. Classification Performance of Proposed Method
6.2. Performance Comparison with SVM and Different Methods
6.3. Performance Comparison with Published Articles
7. Conclusions
Author Contributions
Funding
Conflicts of Interest
Appendix A
PQDs | Label | Equations | Parameter Constrains |
---|---|---|---|
Normal | C1 | ||
Sag | C2 | ||
Notch | C3 | ||
Sag with Swell | C4 | ||
Impulsive Transient | C5 | ||
Oscillatory Transient | C6 | ||
Flicker | C7 | ||
Harmonic | C8 | ||
Sag with harmonic | C9 | ||
Sag, Swell with harmonic | C10 | ||
Sag with Oscillatory Transient | C11 | , | |
Sag, Swell with Oscillatory Transient | C12 |
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Feature Extracted Methods | |||
---|---|---|---|
Energy | Log-energy Entropy | ||
Entropy | Mean | ||
Standard Deviation | Root Mean Square Value | ||
Range | Kurtosis | ||
Crest Factor | Skewness | ||
Form Factor | - | - |
Bus Nodes | Load Model | Load | Capacitor Bank | Modified Data | |
---|---|---|---|---|---|
- | - | kW | kVAr | kVAr | - |
634 645 646 652 671 675 692 611 632–671 650 680 | Y-PQ Y-PQ D-Z Y-Z D-PQ Y-PQ D-I Y-I Y-PQ | 400 170 230 128 1155 843 170 170 200 | 290 125 132 86 660 462 151 80 116 | - - - - - 600 - 100 | - - - - - Switching Fault - Switching Fault - Grid WG/non-linear load |
Transformer | MVA | kV-High | kV-Low | HV Winding | LV Winding | ||
---|---|---|---|---|---|---|---|
Substation(T-1) | 10 | 115 | 4.16 | 29.095 | 211.60 | 0.1142 | 0.8306 |
T-2 | 5 | 4.16 | 0.575 | 0.3807 | 2.7688 | 0.0510 | 0.0042 |
T-3 | 5 | 41.6 | 0.48 | 0.3807 | 2.7688 | 0.0510 | 0.0042 |
Features Vectors | IPC Coefficients | |||
---|---|---|---|---|
D1 | D2 | D3 | D4 | |
RMS | F1 | F7 | F13 | F19 |
Range | F2 | F8 | F14 | F20 |
C-Factor | F3 | F9 | F15 | F21 |
F-Factor | F4 | F10 | F16 | F22 |
Kurtosis | F5 | F11 | F17 | F23 |
Skewness | F6 | F12 | F18 | F24 |
Power Quality Disturbances | Accuracy (%) Comparison between Proposed IPCA-1-D CNN Classifier and IPCA-SVM | |||||||||
---|---|---|---|---|---|---|---|---|---|---|
IPCA-SVM | IPCA-1-D CNN | |||||||||
Class Labelled | Training/Testing Sets | 0 dB | 20 dB | 50 dB | Simulation Data | 0 dB | 20 dB | 50 dB | Simulation Data | |
Normal | C1 | 200 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 |
Sag | C2 | 200 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 |
Notch | C3 | 200 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 |
Flickers | C4 | 200 | 100 | 100 | 100 | 100 | 100 | 100 | 100 | 100 |
Impulsive Transients | C5 | 200 | 99.52 | 99 | 99.32 | 98.8 | 100 | 99.80 | 99.9 | 99.80 |
Oscillatory Transients | C6 | 200 | 100 | 100 | 99.80 | 99.26 | 100 | 100 | 99.95 | 99.78 |
Harmonics | C7 | 200 | 100 | 99.5 | 99.85 | 99.33 | 100 | 99.65 | 99.8 | 99.65 |
Sag with Swell | C8 | 200 | 98.43 | 98 | 98.20 | 97.90 | 100 | 100 | 100 | 99.85 |
Sag with Harmonics | C9 | 200 | 98.29 | 97.88 | 98 | 97.5 | 99.95 | 99.75 | 99.85 | 99.60 |
Sag, Swell with Harmonics | C10 | 200 | 97.10 | 96.83 | 97 | 96.70 | 99.82 | 99.50 | 99.74 | 99.55 |
Sag with Oscillatory Transients | C11 | 200 | 97.75 | 97.15 | 97.25 | 96.84 | 99.75 | 99.20 | 99.42 | 99.3 |
Sag, Swell with Oscillatory Transients | C12 | 200 | 97.50 | 96.80 | 97 | 96.39 | 99.52 | 99.27 | 99.52 | 99.38 |
Accuracy (%) | 99.05 | 98.76 | 98.87 | 98.55 | 99.92 | 99.76 | 99.85 | 99.75 |
Classifier | Feature Extraction Method | |||
---|---|---|---|---|
PCA | IPCA | 1D-CNN | IPCA-1DCNN | |
SVM | 1.565 | 0.859 | 0.725 | 0.792 |
1-D CNN | 1.257 | 0.475 | 0.389 | 0.432 |
Feature Extraction and Classification Algorithms | No of PQ Disturbance | Data Type | PQDs Phase Type | Run Time | No of Features | Classification Accuracy (%) |
---|---|---|---|---|---|---|
WT + LSSVM [64] | 4 | Real | 3- | -- | 21 | 99.71 |
FTT + SR − ELM [4] | 12 | Simulated | 3- | 0.029 | 107 | 99.59 |
OMFST + CA [65] | 12 | Simulated | Single | -- | 67 | 98.92 |
GT + PNN [66] | 9 | Simulated and Real | Single | -- | 6 | 99.51 |
HST + DT + SVM [67] | 7 | Simulated and Real | Single | -- | 13 | 99.5 |
DWT + HST + S VM [68] | 9 | Simulated and Real | 3- | 0.0109 | 20 | 99.44 |
DWT + ABC + PNN [69] | 16 | Simulated and Real | Single | 1.2008 | 72 | 99.875 |
IPCA + 1-D-CNN (Proposed) | 12 | Simulated | 3- | 0.475 | 132 | 99.92 |
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Shen, Y.; Abubakar, M.; Liu, H.; Hussain, F. Power Quality Disturbance Monitoring and Classification Based on Improved PCA and Convolution Neural Network for Wind-Grid Distribution Systems. Energies 2019, 12, 1280. https://doi.org/10.3390/en12071280
Shen Y, Abubakar M, Liu H, Hussain F. Power Quality Disturbance Monitoring and Classification Based on Improved PCA and Convolution Neural Network for Wind-Grid Distribution Systems. Energies. 2019; 12(7):1280. https://doi.org/10.3390/en12071280
Chicago/Turabian StyleShen, Yue, Muhammad Abubakar, Hui Liu, and Fida Hussain. 2019. "Power Quality Disturbance Monitoring and Classification Based on Improved PCA and Convolution Neural Network for Wind-Grid Distribution Systems" Energies 12, no. 7: 1280. https://doi.org/10.3390/en12071280
APA StyleShen, Y., Abubakar, M., Liu, H., & Hussain, F. (2019). Power Quality Disturbance Monitoring and Classification Based on Improved PCA and Convolution Neural Network for Wind-Grid Distribution Systems. Energies, 12(7), 1280. https://doi.org/10.3390/en12071280