Indirect Effective Controlled Split Source Inverter-Based Parallel Active Power Filter for Enhancing Power Quality

Abstract

The existing solutions for reducing total harmonic distortion (THD) using different control algorithms in shunt active power filters (SAPFs) are complex. This work proposes a split source inverter (SSI)-based SAPF for improving the power quality in a nonlinear load system. The advantage of the SSI topology is that it is of a single stage boost inverter with an inductor and capacitor where the conventional two stages with an intermediate DC-DC conversion stage is discarded. This research proposes inventive control schemes for SAPF having two control loops; the outer control loop regulates the DC link voltage whereas the inner current loop shapes the source current profile. The control mechanism implemented here is an effective, less complex, indirect scheme compared to the existing time domain control algorithms. Here, an intelligent fuzzy logic control regulates the DC link voltage which facilitates reference current generation for the current control scheme. The simulation of the said system was carried out in a MATLAB/Simulink environment. The simulations were carried out for different load conditions (RL and RC) using a fuzzy logic controller (FLC) and PI controllers in the outer loop (voltage control) and hysteresis current controller (HCC) and sinusoidal pulse width modulation (SPWM) in the inner loop (current control). The simulation results were extracted for dynamic load conditions and the results demonstrated that the THD can be reduced to 0.76% using a combination of SPWM and FLC. Therefore, the proposed system proved to be effective and viable for reducing THD. This system would be highly applicable for renewable energy power generation such as Photovoltaic (PV) and Fuel cell (FC).

A Review on the Use of Active Power Filter for Grid-Connected Renewable Energy Conversion Systems

“…To obtain every phase of the sinusoidal reference form apply the required voltage for every phase. In such cases, the system performance of medium and high-powered systems, usually in the low power class, does not have any significant impact [146].…”

“…The smooth condenser voltage change, on the contrary, guarantees that the supply/filter loop monitors current variations, which lowers the change frequency further. This technique has the advantage that the supply side does not change the sudden voltage, which reduces the amount that the PWM inverter presents of highfrequency harmonics [146]. for slowly varying or varying loads.…”

Fuzzy Control Systems for Power Quality Improvement—A Systematic Review Exploring Their Efficacy and Efficiency

“…Number of linguistic variables: The most popular number of linguistic variables used in the fuzzification stage for the inputs and outputs was seven [78,79,82,88], followed by five and three [76,80,83]. Considering the differences between the inputs and outputs, the proposed FLCs had the same number of linguistic variables for both inputs and outputs [76], but there were also FLCs characterized by different numbers of linguistic variables [83,87].…”

“…Type of fuzzy numbers (membership functions): The authors extensively used a combination of trapezoidal and triangular membership functions [78,81,83,88], as shown in Figure 4. Close behind are the utilization of the triangular function, the Gauss function [79], and singletons [76]. Other functions used in the fuzzification stage, but rarely, are the bell-shaped, trapeze, and sigmoid functions.…”

“…1. Number of inputs and outputs: The most used configuration is two inputs and one output, with a percentage of more than 75%, of which [76][77][78][79] and [80][81][82][83][84][85][86][87] are typical examples. This aspect is seen clearly in Figure 2, where other configurations that appear in more than one article are one input-one output [88], two inputs-three outputs, two inputs-two outputs, and four inputs-two outputs.…”