Advances in reduction of total harmonic distortion in solar photovoltaic systems: A literature review

Abstract

Summary The use of photovoltaic (PV) systems has increased in recent years due to the high demand for clean energy sources. PV systems can utilize abundant and free energy from the sun, which is a substantial advantage. However, compared with other renewable technologies, the PV system still faces major obstacles such as high cost and low efficiency. In addition, fluctuating incident energy from the sun creates harmonics in the generated power that might lead to undesirable system performance. Total harmonic distortion (THD) is the ratio of distorted power to the main power of the signal, and is most commonly used to indicate the amount of signal distortion. THD has become a serious concern as more PV systems are integrated into grid systems. Previous research and reviews have attempted to reduce THD and its effect, but unfortunately focused on reducing THD at individual parts of the PV system. For the first time, this study holistically and systematically reviews the advances in THD reduction techniques for the entire PV system. The causes of harmonics, current solutions, and research gaps for further investigation are described in detail. Moreover, the current THD reduction techniques used in each stage of the PV system are compared, including their main benefits and drawbacks. Finally, this study recommends the use of adaptive filters as a possible solution for THD reduction because these filters have effectively reduced noise and disturbance in other systems.

Design of a master power factor controller for an industrial plant with solar photovoltaic and electric vehicle chargers

“…The mathematical formula to calculate THD i percentage is given as per Eq. 16 [37]: where I n is the root mean square of the output current and n represents the harmonic number. Figure 11 shows the highest THD i percentage of the designed solar PV system (4.33%) with its relevant spectrum in a graphical form by using a fast Fourier transform analysis feature in Matrix Laboratory/Simulink software.…”

Optimal Hybrid PV Array Topologies to Maximize the Power Output by Reducing the Effect of Non-Uniform Operating Conditions

“…The symmetrical sections of S-P topologies are cross-tied (pink colored line). In Figure 3f, the PV modules (31,32,33,34,35,36) and (41,42,43,44,45,46) are connected at the same node. Hence, both the symmetrical sections of S-P topologies are in series connection.…”

“…Thus, the same current flows through the S-P and T-C-T topologies. The S-P topology is modeled with the modules (11,21,31), (12,22,32), (13,23,33), (14,24,34), (15,25,35), and (16,26,36), and the T-C-T topology is modeled with the modules (41,42,43,44,45,46), (51,52,53,54,55,56), and (61, 62, 63, 64, 65, 66). S-P-T-C-T topology performance is superior over S-P, B-L, H-C, and S-P-C-T topologies under most NUOCs.…”

“…Thus, the same current flows through the B-L and T-C-T topologies. The B-L topology modeled with the modules numbered (21,22,31,32), (12,13,22,23), (23,24,33,34), (14,15,24,25), and (25,26,35,36). The T-C-T topology is modeled with the modules same as in the S-P-T-C-T topology.…”

“…However, the presence of bypass diode connection results in more numbers of maximum-power-points in the I-V and P-V characteristics of array topologies [9]. The various other approaches to mitigate the effect of NUOCs are PV array topologies [10][11][12][13], modified maximum-powerpoint-tracking (M-P-P-T) techniques [14][15][16][17], PV system architectures [18][19][20][21] and the use of multi-level power electronic converters [22][23][24][25][26][27][28][29][30][31][32][33].…”