ABSTRACT:
One
of the serious issues that a Power System faces is the Power Quality (PQ)
disturbance which occur mainly because of the non-linear loads. Among these PQ
disturbances, harmonics play a vital role which should to be mitigated along
with reactive power compensation. In this paper, a modified seven-level boost
Active-Neutral-Point-Clamped (7LB-ANPC) inverter is utilized as a Shunt Active
Power Filter (SAPF). Another vital aspect of this work is to retain the link
voltage across the capacitor, which is accomplished through a PI controller tuned
with an Adaptive Neuro-Fuzzy Inference System (ANFIS). An adaptive
instantaneous p-q theory is instigated in the direction of extracting reference
current and the harmonic extraction is carried out by using Radial Basis
Function Neural Network (RBFNN). Gating sequence of inverter is generated for
the outputs, which are attained from ANFIS and RBFNN and thus the opposite
harmonics are injected to the Point of Common Coupling (PCC) by which current
harmonics are eliminated with reactive power compensation. The 7Lb-ANPC
inverter has a minimized number of switching devices with low switching losses
and high boosting ability. By RBFNN based reference current generation, the
source current THD of 0.89% is achieved. The proposed methodology is simulated
through MATLAB and in hardware by utilizing FPGA Spartan 6E.
KEYWORDS:
1. Power
Quality
2. Shunt
Active Power Filter
3. Multi-Level
Inverters
4. Active-Neutral-Point-Clamped
Inverter
5. Radial
Basis Function Neural Network
6. Adaptive
Neuro-Fuzzy Inference System
SOFTWARE: MATLAB/SIMULINK
SCHEMATIC DIAGRAM:
Figure 1 Proposed Seven-Level ANPC Circuit Diagram
EXPECTED SIMULATION RESULTS:
Figure 2: Source Voltage waveform
Figure 3: Load Current waveform
Figure 4: Current injected at the PCC
Figure 5: Source Current
Figure 6: DC-link voltage
Figure 7: THD waveform with the RBFNN approach
Figure 8: THD waveform with PQ theory
CONCLUSION:
In
this paper, harmonic mitigation and reactive power compensation are
accomplished through a modified seven-level boost ANPC inverter, which exhibits
high boosting ability with a minimized number of switches and low switching
losses. The reference current generation is highlighted through the adaptive
instantaneous p-q theory with RBFNN. Link voltage in the capacitor is retained
by using ANFIS and which is compared by the PI controller and Fuzzy. PWM
generator with a hysteresis current controller has generated the required
gating sequence for the modified 7LB-ANPC inverter. A detailed comparison of
modified 7LB-ANPC with the recent strategies has been carried out. The
simulation results has highlighted that the proposed methodology is well suited
for harmonic mitigation.
REFERENCES:
[1] P. S. Harmonics, "Power System Harmonics: An Overview," in IEEE Transactions on Power Apparatus and Systems, vol. PAS-102, no. 8, pp. 2455-2460, Aug. 1983, doi: 10.1109/TPAS.1983.317745.
[2] M. Rastogi, R. Naik and N. Mohan, "A comparative evaluation of harmonic reduction techniques in three-phase utility interface of power electronic loads," in IEEE Transactions on Industry Applications, vol. 30, no. 5, pp. 1149-1155, Sept.-Oct. 1994, doi: 10.1109/28.315225.
[3] R. Arnold, "Solutions to the power quality problem," in Power Engineering Journal, vol. 15, no. 2, pp. 65-73, April 2001, doi: 10.1049/pe:20010202.
[4] D. Graovac, V. Katic and A. Rufer, "Power Quality Problems Compensation With Universal Power Quality Conditioning System," in IEEE Transactions on Power Delivery, vol. 22, no. 2, pp. 968-976, April 2007, doi: 10.1109/TPWRD.2006.883027.
[5] B. Singh, K. Al-Haddad and A. Chandra, "A review of active filters for power quality improvement," in IEEE Transactions on Industrial Electronics, vol. 46, no. 5, pp. 960-971, Oct. 1999, doi: 10.1109/41.793345.
