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Conventionally, the parameters of a fuzzy logic controller (FLC) are obtained by a trial and error method or by human experience. In this paper, the problem of designing a FLC for maximum power point tracking (MPPT) of a photovoltaic system (PV) that consists of a PV generator, a DC-DC boost converter and a lead-acid battery is studied. The normalization gains, the membership functions and the fuzzy rules are automatically adjusted using a particles swarm optimization algorithm (PSO) in order to maximize the criterion based on the integration of the PV module power under standard temperature condition (STC) (T=25ºC and S=1000 W/m2). The robustness test of the optimized fuzzy logic MPPT controller (FLC-MPPT) is carried out under different scenarios. Simulation results of the system clearly show that the proposed optimized FLCMPPT controller outperforms in terms of maximum efficiency the FLC-MPPT controller not optimized, the FLC-MPPT controller with optimized normalization gains and the FLC-MPPT controller with optimized normalization gains and membership functions.

This paper describes the development and implementation of a hybrid energy system combining photovoltaic (PV) panels and battery storage (BS), This choice stems from the imperative need to overcome challenges posed by solar energy's intermittency, load variability, and efficient battery management. The proposed hybrid system incorporates a photovoltaic (PV) generator employing a fuzzy logic controller (FLC) based maximum power point tracking (MPPT) technique. The harnessed solar energy is then used to power a variable load connected to a battery, all orchestrated by a PI controller in a buck-boost configuration. The objective of this system is to optimize the utilization of solar energy and enhance the overall performance of the hybrid energy system. This research contributes to the advancement of renewable energy technologies, enabling efficient utilization of solar energy and improving the overall performance and reliability of hybrid energy systems. The Matlab/Simulink results show that the suggested PI controller delivers a stable DC bus with reduced chatter under quick irradiation and load changes. [ABSTRACT FROM AUTHOR]

This paper deals with the modeling and control of a new two-stage photovoltaic conversion cascade composed of a Three-Level Boost (3LB) converter and a three-phase NPC fivelevel inverter (5LI). The main objective is to ensure the continuity of energy transfer from a renewable continuous source to the electrical grid while regulating the voltages of the DC bus capacitors with a new proposed configuration. The 3LB is controlled in MPPT based on fuzzy logic. A PI regulator is introduced into the 3LB regulation loop in order to maintain the equality of the two output voltages. The overall voltage of the DC bus being regulated by the control of the multilevel inverter interconnected to the grid, using synchronous reference frame control. Therefore, in our case there is the problem of voltages imbalance caused by the 5LI. We propose in this work to introduce two Clamping Bridges (CBs) each one is composed by a transistor in series with a resistor. These CBs are introduced in parallel with two capacitors of the DC bus. This solution avoids us to use the control algorithm by redundant configurations in the regulation loop of the 5LI. The results obtained show the effectiveness of the proposed control in stabilizing and maintaining the four DC bus voltages at equal values. With four balanced capacitor voltages, we get symmetrical inverter output voltage waveforms, which directly affects the quality of the current injected to the grid. [ABSTRACT FROM AUTHOR]

finite control set model predictive control (FCS-MPC) based controller has a fast dynamic response and robustness. furthermore, the presence of a cost function gives designers a degree of freedom to include system control targets, constraints and system non-linearities. On the other hand, Multilevel inverter (MI) topologies are becoming a strong alternative in distributed power generation system (DPGS), among these topologies is the three-phase three-level NPC (TTLNPC) inverter. Generally, to properly operate this topology, the applied current control ensures the achievement of two main objectives. First, the output current must be controlled to track its reference. Second, the two dc-link capacitor voltages have to be equal and balanced. In this paper, FCS-MPC is proposed to control the TTLNPC inverter based parallel active power filter (APF) adopted to connect a photovoltaic system (PVS) to the grid and perform a harmonic mitigation. The proposed FCS-MPC exploit the model of the system to predict the future values of the inverter currents by selecting the best voltage vector that aims to minimize a predefined cost function. Instead of using the popular redundant vectors algorithms to balance the twosplit dc-link capacitor voltages, another term will be added to the expression of the cost function to achieve this goal. The PV panel is coupled directly to the inverter without DC/DC converter, the P&O MPPT algorithm is responsible to generate the capacitor reference voltage whatever the climatic conditions are. Simulations using Matlab/Simulink were performed to prove the efficiency of the proposed technique to mitigate the grid current harmonics, and to ensure a continuous power injection and perform a load power sharing. [ABSTRACT FROM AUTHOR]

This paper proposes a regulation method of back-to-back connected two-level PWM rectifier-five-level Voltage Source Inverter (VSI) in order to reduce the torque ripple in induction motor. First part is dedicated to the presentation of the feedback control of two-level PWM rectifier. In the second part, five-level Neutral Point Clamped (NPC) voltage source inverter balancing DC bus algorithm is presented. A theoretical analysis with a complete simulation of the system is presented to prove the excellent performance of the proposed technique.

This paper proposes a new optimized control of photovoltaic two stages conversion cascade composed by Three Levels Boost (TLB) and Three Levels Neutral Point Clamped (TLNPC) inverter. In order to extract the maximum power from photovoltaic generator and get a balanced DC bus voltage, the duty cycles of the two TLB switches are determinate from a Fuzzy Logic Controller (FLC) for the first switch and by adding to the first duty cycle an additional duty cycle obtained by integration of the error between the two capacitors voltages of DC bus. Balancing the bus voltages by the TLB using a single regulator avoid us to use a complex balancing algorithm by the redundant vectors of TLNPC inverter. For the control of the inverter, we used a Proportional Integral (PI) regulator optimized by PSO. This command allows us to have on one side a constant DC bus voltage and a current injection in phase with the grid voltage. To have an efficient follow-up of the TLNPC inverter reference voltages, the Space Vector Pulse Width Modulation (SVPWM) is applied. The simulation is carried out in MATLAB/SIMULINK platform. The results obtained from the application of the FLC command associated with PI PSO are better compared to the simulation without optimization in terms of sum of the absolute values of the errors at the inputs of the three PI regulators. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to develop a control and regulation method for the input DC voltages of a 5-level neutral point clamping (NPC) active power filter (APF). This APF is applied for the enhancement of medium-voltage network power quality by compensation of harmonic currents produced by an induction motor speed variator. In the first part, the authors present a topology of a 5-level NPC voltage source inverter and its simplified space vector pulse width modulation (SVPWM) control strategy. In the second part, the control strategy of the 5-level pulse width modulation current rectifier is presented. In the third part, to remedy to instability problem of the input DC voltages of the APF, the authors propose the feedback control of the 5-level rectifier associated with a simplified SVPWM with the redundant vectors method for the 5-level APF. After that, the sliding mode regulator used to control the APF is developed. The application of the proposed control algorithm offers the possibility of stabilizing the DC voltages of the APF. The stable DC bus supply associated with the sliding regulator of the APF allows the obtainment of low-harmonic content network currents with unity power factor. The instability problem associated with the use of the multilevel APF is solved. The obtained results are full of promise for the use of the multilevel APF in medium-voltage and high-power applications. [ABSTRACT FROM AUTHOR]

This paper proposes an open switch faults detection and localization algorithm for shunt three phase active filter topology. It mainly details converter configuration and examines a simple and reliable optimized fault diagnosis method. The converter topology is based on classical three-leg active power filter topology. New fault diagnosis method is proposed, based on classical currents measurements. It includes combinatory logic to analyze and validate error signals. Hysteresis control is applied before and after fault detection, which avoids any controller reconfiguration. Simulation results obtained with Matlab/Simulink/Plecs tools prove the effectiveness of this method. [ABSTRACT FROM AUTHOR]

One of the most important drawbacks of the three phases five-level NPC (Neutral Point Clamped) Active Power Filter (APF) is the neutral point balance. As the consequence, the capacitors voltages of the input DC bus of the APF are not equal which constitutes the major limitation for the use of this power converter. In order to stabilize these DC voltages, it is proposed in this paper to study the cascade constituted by three phases three-level PWM rectifier-clamping bridge filter-five-level NPC APF. In the first part, the authors present a topology of five-level NPC Voltage Source Inverter (VSI), and then, they propose a model of this converter and its PWM control strategy. In the second part, the modeling and control of three-level PWM current rectifier is presented. In the third part, to remedy to instability problem of the input capacitors DC voltages of the APF, the authors propose feedback control of the three-level PWM rectifier followed by clamping bridge filter. After that, the sliding mode regulator used to control the active filter is developed. The obtained results are full of promise to use this topology of APF in high voltage and high power applications. [ABSTRACT FROM AUTHOR]

In renewable system control engineering, Maximum Power Point Tracking (MPPT) techniques are considered as one of the key steps in photovoltaic (PV) system development. Indeed, some MPPT techniques provide high performance under uniform irradiation and temperature conditions. However, their performance significantly degrades when the two preceding climatic conditions suddenly change. Therefore, this paper proposes a new voltage regulation based on Fuzzy Logic Control (FLC) strategy and small-signal model of DC–DC booster converter. The proposed control scheme is mainly based on the indirect incremental conductance (Inc) technique, equipped with an optimal integrator controller (OIC). It is implemented in a PV system, consisting of a DC–DC boost converter connected to a resistive load, with the main objective of ensuring a good MPP tracking behavior for variable operating conditions. To achieve this objective, the proposed MPPT strategy is designed around two stages. First, the smooth reference voltage is ensured by a Single-Input Single-Output (SISO) fuzzy logic controller using the Inc technique based on the MPPT approach. Then, the optimal integrator controller stabilizing the closed-loop system is integrated with optimization of its parameter according to Routh’s criterion for resistive load variations. Simulation results confirm the effectiveness of the proposed MPPT technique compared to some commonly used MPPT approaches. The superiority of the proposal is proven by using efficiency ratio, which rises more than 98% in all case studies. These objectives are ensured for both uniform and critical sudden change in weather conditions, regardless of resistive load variations. [ABSTRACT FROM AUTHOR]