CONTROL OF SHUNT ACTIVE PHOTOVOLTAIC COMPENSATOR FOR SMART GRIDS

In the electrical distribution networks and smart grids, the widespread adoption of the power electronics components among customer loads poses diverse challenges to power quality. The integration of Renewable energy sources, to these networks and grids, further exacerbates these challenges due to voltage fluctuations, frequency deviations, and waveform distortion inherent in these sources, which its performances are significantly dependence on weather conditions. Within this framework, this thesis addresses these challenges through three distinct solutions involved for power quality improvement in the distribution networks, with a focus on integrating renewable energy sources, particularly photovoltaic (PV) systems, in the third solution. The first solution introduces an innovative multi-level structure of AC/DC/AC Converter. This solution opts to regulate the voltage amplitude, ensure sinusoidal-like output stepping voltage, and mitigate a wide harmonics rank, including the predominant harmonics whose suffer sensitive loads such as asynchronous motor drives. To address these aspects, this work develops a novel modulation technique to control the DC/AC part of the converter, which is configured via Asymmetrical Cascaded H-Bridge Inverter. The second solution involves An Advanced Hybrid Control System Developed for Shunt Active Filter Based on Multi-Level Inverter. This solution improves the performance of the shunt active filter, raises its apparent switching frequency, and then, reduces the size of its output coupling filter. Furthermore, the hybrid controller, implemented using Petri Nets (PNs), ensures high performance tracking of the compensating current, in addition to stabilize, control, and balance the DC voltages across the MLI inputs. However, the practical stability of the DC voltage errors is analytically proved via the Lyapunov theorem. This solution is explored in detail for n H-Bridge modules per phase, while the real measurement and simulation validations are evaluated for 2 and 3 H-Bridge modules per phase within real industrial environment to prove the structure effectiveness. The third solution presents a Grid-Connected PV Structure Incorporated with Shunt Active Filter Based on Multi-Level Inverter structure. This configuration not only enhances power quality but also provides renewable energy for both loads and grid. In this innovative structure, the DC inputs of the multi-level inverter are connected directly to PV subsystems or via DC-DC converters. Linear controllers are employed to establish the control strategy for the shunt active filter based on (n) H-bridge modules, which include injecting compensating current, maximizing the produced power of the PV system, and regulating DC voltages across capacitors. Multi-carrier PWM modulation relatively ensures balanced power distribution among the modules. Maximum Power Point Tracking (MPPT) algorithms, such as Perturb & Observe (P&O), with three control strategies including Proportional Integral, Duty-cycle, and Model Predictive Controller, are employed to maximize PV subsystem power generation. Additionally, the DC-DC converter utilizes PWM modulation techniques across all three control strategies to maintain a consistent switching frequency. The performance of the three aforementioned solutions is validated, for finite HB modules, within a textile factory suffering from harmonic impact on sensitive load of 50 kVA which represents asynchronous motor drive. This motor drive is extremely sensitive to predominant ranks of torque and voltage harmonics, Therefore, on-site measurements using power quality analyzer devices are collected to accomplish numerical model of the entire factory's network. Finally, the performance of each solution is investigated on the Sensitive Load operating of the textile factory.