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A new bidirectional Z-source Matrix Converter is introduced and designed to be implemented in a Wind Energy Conversion System (WECS) using a direct-drive Permanent Magnet Synchronous Generator (PMSG). It is designed to overcome the main constraints of matrix converters such as their relatively complex modulation techniques, their high number of semiconductor switches and their voltage gain limited to 0.866. It is implemented in a PMSG-based WECS. The control strategy is based on the Rotor-Flux-Orientation Control and the optimal Tip Speed Ratio (TSR) Maximum Power Point Tracking (MPPT) algorithm while the modulation technique is the Space Vector Modulation (SVM). The performances of the overall WECS with the proposed control strategy are examined under wind speed variations. The impact of wind speed intermittency on the frequency responses is evaluated and results show that the Series Z-Source Very Sparse Matrix Converter (SZS-VSMC) is a promising solution for storage-free step-up AC-AC conversion applied in PMSG-based WECSs. The effectiveness of the proposed power converter and its implementation are verified using MATLAB/Simulink simulations performed initially with a RL load and then connected to the grid.

This paper discusses an existing Direct Power Control algorithms for three-phase three-level with neutral-point clamped (NPC) rectifiers. Direct Power Control, or DPC, implies the creation of the control algorithm in order to directly control both the active and reactive powers consumed by the rectifier, increasing the grid's power factor and reducing its current total harmonic distortion. Throughout this document, we will focus on one control algorithm directly related to DPC, through which we can achieve the rectifier control. The chosen method is the virtual flux based on DPC with space vector modulation. We will develop the mathematical model stemming from this algorithm and its operation under variable load. These tests and implementations will allow us to assert the superiority of virtual flux DPC with space vector modulation algorithm over conventional control techniques, verify the results obtained through the studied literature, and demonstrate the capacity of the algorithm to abide by the requirements and constraints. These tests will valorize, when working with medium to high power loads, the advantages of a multi-level inverter.

The paper proposes a very simple hybrid modulator whose role is to control the rectifier & inverter stages of a five-phase indirect matrix converter topology. The adopted technique combines between two forms of pulse width modulations PWM and due to this combination, the system advantageously requires very little computation efforts, resulting in high quality waveforms on both source & load extremities. This modulator wins over its previous conventional schemes by ensuring reduction in calculation times along with total preservation of voltage and current act.

In this paper, a new control design is developed for the Packed U-Cells (PUC) inverter. A fixed-switching frequency Model Predictive-based (MPC) algorithm is introduced for the sensor-less five-level (PUC5) inverter to regulate the current injected to the utility when it operates in grid connection mode. The proposed method generates the candidate vector that minimizes the well-known Finite Set Model Predictive (FS-MPC) cost function. Besides, the sensor-less voltage control of PUC5 takes in action of stabilizing DC capacitor voltages with no need of additional regulator. Less complexity with no sensors, nor required iterations are obtained. Discrete system model has been introduced and developed. Simulation results on MATLAB/Simulink are provided to confirm the effectiveness and robustness of the proposed algorithm.