Omar Abdel-Rahim

Grid-tie switched inductor with voltage multiplier inverter

This paper presents a novel high gain two-stage inverter for Photovoltaic (PV) applications. First stage consists of very high gain Switched Inductor with Voltage Multiplier (SIVM) dc-dc converter. Construction of the second stage consists of five-switch dc-ac inverter. The proposed converter mainly designed for grid-connected PV applications. The proposed system can do the following functions: boost low dc-input voltage to higher level suitable for grid connection, convert dc-voltage into ac voltage and inject sinusoidal current in phase with the grid voltage. Control of the proposed system is performed using Model Predictive Control (MPC). MPC has some inherent features such as Simple and easy to implement, it can be applied to a great variety of systems. Simple treatment of constraints. Control Algorithm is designed to perform the following functions: extract maximum power from PV module, boost low dc-voltage of PV module and inject sinusoidal current synchronized with the grid voltage.

Modified maximum power point tracking technique based on fixed frequency model predictive control for PV applications

A novel Maximum Power Point Tracking Technique (MPPT) based on Fixed Frequency Model Predictive Control (FFMPC) for Photovoltaic (PV) is developed through this paper. The Proposed control system consists of two-stage. The first stage is a Modified Incremental Conductance (MIC) algorithm and the second stage is FFMPC. The proposed control system has some inherent features such as fast MP tracking under different environmental conditions, working at fixed frequency, and this gives the advantages of controlling the output quality and EMI, and smaller transient time. Switched Inductor Quadratic Boost Converter (SIQBC) is used as an interface stage for MPPT. SIQBC has very high gain with acceptable efficiency.

Novel Predictive Maximum Power Point Tracking Techniques for Photovoltaic Applications

This paper offers two Maximum Power Point Tracking (MPPT) systems for Photovoltaic (PV) applications. The first MPPT method is based on a fixed frequency Model Predictive Control (MPC). The second MPPT technique is based on the Predictive Hysteresis Control (PHC). An experimental demonstration shows that the proposed techniques are fast, accurate and robust in tracking the maximum power under different environmental conditions. A DC/DC converter with a high voltage gain is obligatory to track PV applications at the maximum power and to boost a low voltage to a higher voltage level. For this purpose, a high gain Switched Inductor Quadratic Boost Converter (SIQBC) for PV applications is presented in this paper. The proposed converter has a higher gain than the other transformerless topologies in the literature. It is shown that at a high gain the proposed SIQBC has moderate efficiency.

Novel fixed frequency predictive hysteresis maximum power point tracking control for photovoltaic applications

A novel Maximum Power Point Tracking (MPPT) control for Photovoltaic applications is proposed in this paper. The proposed control algorithm is two-stage control system. The first stage is a Modified Incremental Inductance (MIC) algorithm and the second stage is based on Fixed Frequency Predictive Hysteresis Control (FFPHC). The purpose of the MIC stage is to generate the required reference current that achieves the maximum power. And the function of the FFPHC is to force the system to track that reference. The proposed control algorithm has some inherent features such as ability to achieve maximum power even in case of rapid environmental changes, ability to achieve maximum power in case of partial shading. Operation of predictive hysteresis control at fixed frequency gives the advantages of better power stage parameters design and enables controlling the switching losses.

An efficient MPPT technique with fixed frequency finite-set model predictive control

This paper proposes Fixed Frequency Model Predictive Control (FFMPC) based MPPT algorithm and SIQBC for PV Applications. The proposed control algorithm consists mainly from two stages, the first stage is a modified Incremental Conductance (IC) algorithm and the second stage is a modified fixed frequency model predictive control. The proposed MPPT algorithm has a fast response, able to extract maximum power under different environmental conditions, reach to steady state faster than traditional IC algorithm and it operates at fixed switching frequency. The proposed algorithm has the advantages of fast tracking, fixed switching frequency and less ripple at Maximum Power Point (MPP). The proposed algorithm was implemented and applied on high gain Switched Inductor Quadratic Boost Converter (SIQBC). As described and illustrated on the experimental results, the proposed algorithm can track the maximum power in very small time, even in case of fast environmental change. The proposed algorithm is presented using PE Expert III.

Pseudo single stage flyback current source inverter for grid connected PV applications

Pseudo single stage flyback current source inverter designed for photovoltaic applications is presented in this paper. The proposed inverter consists of flyback current source converter and h-bridge unfolding stage. The proposed system is intended to do the following functions: extract maximum power for the Photovoltaic (PV) module, inject a sinusoidal current into the grid. Flyback converter is designed to operate in Discontinuous Conduction Mode (DCM), the purpose of DCM operation is to inject a sinusoidal current into the grid without measuring the grid current. Rectified sinusoidal modulation is used to control the flyback converter switch. The purpose of this modulation strategy is to let the output of the flyback converter current to be a rectified sinusoidal waveform. H-bridge unfolding stage is used to convert the rectified current at the fundamental frequency of the grid voltage to full sinusoidal current. All switches of the h-bridge unfolding circuits are operating at fundamental frequency of the grid. Operating at fundamental frequency reduces the switching losses of the h-bridge inverter to be approximately zero.

Multiphase Wind Energy generation with direct matrix converter

This paper proposes a multiphase power generation with matrix converter for Wind Energy Conversion System (WECS). The proposed system consists of five-phase Permanent Magnet Synchronous Generator (PMSG), to generate five-phase voltage with variable amplitude and frequency. The grid is a three-phase system and hence deployment of multiphase generator needs some sort of phase conversion system. Therefore, a five-to-three phase Direct Matrix Converter (DMC) is used to interface the five-phase PMSG with the grid. The choice of multiphase machine comes from the inherent advantages of multiphase machine such as higher output power, reduced phases losses, reduced sized for the same amount of output power compared to three phase generator. The proposed control strategy for the converter is Model Predictive Control (MPC). The proposed algorithm does the following functions: extract maximum power from the WECS, and ensures unity power factor at the grid terminal and machine terminal.

An experimental investigation of modified predictive hysteresis control based MPPT strategy for PV applications

Simple DC micro grid is presented in this paper. The dc micro grid consists of PV module, Switched Inductor with Voltage Multiplier Converter (SIVMC), DC load or battery and maximum power point tracking controller. Switched Inductor with Voltage Multiplier Converter (SIVMC) is used due to its inherent features such as high gain, low voltage stress on the switch and better efficiency. For maximum power point tacking, modified maximum power point tracking algorithm based on fixed frequency predictive hysteresis controller is proposed in this paper. The MPPT controller includes two stages, the first stage is the well-known Incremental Conductance algorithm and the second stage is based on the predictive hysteresis controller. Adding predictive hysteresis stage to the IC algorithms give some advantages such as: fast tracking response, less ripple at the power due to the use of small incremental value.

Switched inductor quadratic boosting ratio inverter with proportional resonant controller for grid-tie PV applications

This paper presents High-gain power conditioning system for grid connected PV applications. The construction of the proposed system consists of high-gain Switched Inductor Quadratic Boost Inverter (SIQBI) and five-switch h-bridge inverter. The proposed system is controlled to satisfy the following criteria: extract maximum power from PV module, boost dc voltage to higher level and inject sinusoidal current in phase with the grid voltage. Proportional Resonant Controller (PRC) is used to control the inversion stage to inject sinusoidal current into the grid. Simulation results and detailed analysis are discussed in details through this paper. Experimental prototype is built, samples of the experimental results are figured out and discussed.

High gain inverter based on the 3S inverter with model predictive control for PV applications

This paper presents two-stage power conditioning system for grid integrated Photovoltaic (PV) applications. The proposed system has distinct feature such as: high voltage gain, high efficiency, low voltage stress and galvanic isolation. The system is controlled via Model Predictive Control (MPC) to do the following functions: extract maximum power from the PV generator, and inject a sinusoidal current into the utility with unity power factor.