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The fight against weed remains one of the major challenges in agriculture to improve land productivity. The first and most important step of this fight is to detect and locate this weed. Artificial intelligence has played a very important contribution in this detection. Several applications have been developed using Deep Learning techniques to detect and identify weed, but the variety of weed types complicates this operation. We propose a Deep Learning technique to detect and localize the crop, by training the pretrained Faster RCNN ResNet model with a rich dataset. We developed an algorithm able to detect and ultra-localize the pea crop with a prediction up to 100%. The obtained results show the feasibility of this method to distinguish the crop among weed.

In this paper, the authors propose a new three-phase, nine-level inverter with self-balancing of capacitors voltages. The proposed inverter is the result of a serial connection of the SPUC topology and the NPC converter. A single DC source is used, and each phase is made up of nine power switches and three capacitors. Two control techniques are proposed to maintain capacitors voltages at desired values, the first of which is a PWM technique ensures the self-balancing of capacitors voltages in open loop without using any filters or PI regulators, and the second is based on the hysteresis control which offers a nearly sinusoidal waveform of the load current without using any voltage sensors. The authors make use of the Matlab Simulink environment to perform the simulation of the proposed concept. The dynamics of the latter was verified against load change.

In this work, an advanced pulse width modulation (PWM) technique was developed to provide the auto-balancing of the capacitors voltages of the five-level split-packed U-Cells (SPUC5) single-phase inverter, and then, the latter was applied to a photovoltaic (PV) system in standalone mode to evaluate its performance in this kind of application. The SPUC5 inverter makes use of only five switches (four active bidirectional switches and one four quadrant switch), one DC source and two capacitors to generate five levels of output voltage and a current with a quasi-sinusoidal waveform which reduces the total harmonic distortion (THD) without the need to add filters or sensors, and also reduces its cost compared to the other multilevel inverters. In the proposed system; the incremental conductance (INC) algorithm is combined with a DC/DC boost converter to reach the maximum power (MP) of the PV array by tracking the MP point (MPP). The offered concept has been constructed and then simulated in the MATLAB/Simulink environment to evaluate its efficiency. According to the results, the self-balancing of the capacitors voltages has been achieved. A comparative study was performed with the traditional PWM technique. The proposed PV system has been validated by experimental results.

The authors provide a novel hysteresis control method for the SPUC inverter in this paper. The suggested system, which consist of the SPUC inverter and the balancing algorithm can offer eleven levels at output voltage using only seven switches, a closed loop is applied to maintain capacitors voltage at desired values, another hysteresis control that ensures capacitors voltage self-balancing is implemented in open loop which result in the proposed SPUC9 inverter .No voltage sensor or filtering is needed, as a consequence the inverter and installation expenses are kept to a minimum. The authors utilized MATLAB/Simulink environment to simulate the proposed converters. Simulation results prove all the concepts given in this paper. Total harmonic distortion remains reduced and depends on the hysteresis bandwidth

In this paper, a new single-phase grid-connected photovoltaic (PV) system, based on the five-level S-Packed U-Cell (SPUC5) inverter, is presented. This novel topology requires a minimum number of components while providing a maximum number of voltage levels. The Pulse Width Modulation (PWM) controller is applied to the five-level SPUC inverter in order to insure the self-balancing to the capacitors voltages and fix them to the half of the DC-link voltage. The Incremental Conductance (INC) is the method of controlling the DC/DC converter chosen by the authors to reach the Maximum Power Point (MPP) delivered by the PV array. Simulation results obtained using MATLAB/Simulink environment prove the high efficiency and the good dynamic of the proposed system even in case of radiation changes. The Total Harmonic Distortions (THD) of the output current is less than 5% which corresponds to the grid injection standards even without using filters.

A new inverter with natural balancing of capacitors voltages is presented in this paper. The proposed topology which is based on the PUC and NPC topologies allows the possibility of generating nine levels at the output voltage while using a single DC source. A PWM technique is designed to ensure the natural balancing of capacitors voltages in open loop. No PI regulators or filters are needed which result in a very simple implementation. Operation of the topology including dynamics verification is validated through simulations in MATLAB/ Simulink.

In this paper, a standalone single-phase photovoltaic system is proposed, the topology used in this system is the five-level S-Packed U cells (SPUC) inverter. This latter is utilizing only one DC source, two capacitors, four active bidirectional switches, and one four-quadrant switch to generate five levels output voltage with reduced total harmonic distortion (THD). It is controlled by the Pulse Width Modulation (PWM) technique to provide the capacitors balancing. A DC/DC boost converter is used to magnify the voltage produced by the PV array, this converter is controlled by the Incremental Conductance (INC) in order to track the Maximum Power Point (MPP). The proposed system is developed and simulated using the MATLAB/Simulink environment, under constant and variable irradiations, to examine the efficiency of the SPUC five-level inverter applied to the standalone PV system.

This paper describes a grid connected photovoltaic system while using single phase multilevel inverter, the chosen topology is Split Packed-U-Cells inverter (SPUC), this application proved that the SPUC inverter can be used in the single phase grid connected applications generally and in the renewable energy applications particularly. It is characterized by the fact that it gives nine levels with only seven switches and two capacitors as it is able to generate sinusoidal AC current with a total harmonic distortion that meets the standards of the injection on the grid without using filters. A Pulse-Width Modulation (PWM) control technique is developed to balance capacitors in open loop condition. After the production of electrical energy by the PV array; a maximum power point tracking (MPPT) algorithm is performed to generate the maximum power to the grid. The proposed system was verified by simulation in MATLAB/Simulink to prove the efficiency of the proposed system.

A new nine level inverter is presented in this paper. It combines PUC and NPC topologies to create a new competitive converter that makes use of small count of power devices to generate more voltage levels. A PWM technique is designed to insure the self balancing of capacitors voltages. Moreover, no filters or regulation loop is required which permits a low inverter and installation cost. Authors make use of Matlab Simulink environment to perform the simulation of the proposed concept. Dynamics of the latter was verified against load and DC source voltage change.

This paper investigates the application of Model Predictive Control (MPC) for controlling the load current and balance capacitors voltages of a nine-level Packed U-Cell inverter in both grid-connected and stand-alone modes of operations. PUC inverter has the advantage of minimum manufacturing cost compared to other multilevel topologies, but it needs bulky dc capacitors. Therefore, this paper proposes the MPC as a proper solution to optimize the capacitors size of nine-level PUC inverter, which makes it more interesting for various industrial applications particularly for single-phase grid-connected devices. For this purpose, structure of nine-level PUC is firstly investigated in terms of switching states, advantages and disadvantages. Afterwards, MPC control method has been developed and designed based on the mathematical equations of nine-level PUC topology. The proposed control loop is thereafter simulated using Matlab/Simulink software and the obtained results prove the desired load current reference tracking and capacitors voltages balancing with optimized capacitance; while minimum Total Harmonic Distortion (THD) and low capacitors voltages ripple have been observed.

In this paper, a novel PWM technique insuring the self-balancing of the capacitors voltages has been proposed for the attained nine-level packed $\mathbf{U}$ cells (PUC) converter. In the traditional fifteen-level operation, the capacitors voltages have to be maintained around their references using a state variable feedback which requires three sensors, two for the capacitors voltages and one for the load current. By applying the proposed PWM technique to the fifteen-level PUC converter, self-balancing of the capacitors voltages is attained, which results in the proposed nine-level converter. The proposed balancing technique is achieved without any closed loop regulation or sensors. The proposed concept has been verified by mean of simulations performed in the Matlab Simulink environments. Simulation results show that even under severe DC bus voltage and load parameters variations, the capacitors voltages remains around their required values. Harmonics contents of load current depend on the modulating signal frequency. Moreover, even under low frequencies, the total harmonics distortion remains reduced.

This paper discusses the design and topology of the indirect matrix converter. The double space vector modulation technique (DSVPWM) is applied on the system and a unity power factor was accomplished along with desired sinusoidal input and output waveforms. The whole system is simulated using Matlab/Simulink, and the results prove to comply with the existing power quality standards.

In this paper, the authors propose a novel six-band hysteresis technique to efficiently control the seven-level packed U cells (PUC) converter. The proposed PUC combines advantages of the flying capacitor and the cascaded H-bridge topologies. The novel control strategy is proposed in order to insure a good operation of the PUC converter in both inverter and rectifier modes. In case of rectifier operation, the proposed six-band controller is designed to draw a sinusoidal line current (load current in case of inverter operation) with a unity power factor. Harmonics contents of line current (or load current) and rectifier input voltage (or inverter output voltage) are very low which permits the reduction of the active and passive filters ratings resulting on a very high energetic efficiency and a reduced installation cost. The proposed concept was validated through experimental implementation using real-time controller, the DS1103 of dSpace.

In this paper, authors propose a new power multilevel converter topology that is very competitive compared to the existing ones. It consists of packed U cells (PUC). Each U cell consists of an arrangement of two power switches and one capacitor. It offers high-energy conversion quality using a small number of capacitors and power devices and consequently, has a very low production cost. An averaged model of the topology is detailed. The operating principle of the transformerless seven-level inverter is analyzed and detailed. The multilevel sinusoidal modulation has been adapted for use with the PUC-based structure. The control strategy has been designed to reduce the harmonic contents of the load voltage. With such converters, filters' rating is considerably reduced. A comparative study is performed to highlight the advantages of the new packed U cells topology. The operation of the proposed converter topology has been verified through simulation. Experimental validation was performed using DS1103 DSP of dSpace.

In this paper, authors propose an advanced photovoltaic system based on the 15-Level PUC inverter. The proposed inverter has the advantage to operate with a single PV array while generating fifteen voltage levels. Even it is constituted from only eight switches and two capacitors; it can nevertheless offer a fifteen-level output voltage. In order to extract the maximum power from the PV panel, authors makes use of the incremental conduction MPPT technique. Associated to the proposed multiband hysteresis control technique, the load voltage and current are nearly sinusoidal. With such waveforms, there is no need of additional investment in any filters. This also increases the system energetic efficiency. Authors' choice has been focused on the Canadian Solar 220W CS5P-220P Panel which is among the top ranked in PVUSA Test Conditions (PTC) ratings established by the California Energy Commission. The proposed concept was verified by simulations performed in the Matlab Simulink and SimPowerSystem environments.

In this paper, authors presents a novel competitive 31-level converter which makes use of small number of power switches and passive components. In case of DC/AC conversion, the proposed 31-level inverter allows a nearly sinusoidal output voltage resulting on a perfectly sinusoidal load current. In case of AC/DC conversion, it presents a reduced impact on the utility supply and a good energetic efficiency. An average model of the proposed converter is performed and a control strategy is designed in order to draw a nearly sinusoidal current and voltage. Active and passive filters can thus be avoided resulting on a highest energetic efficiency and a reduced installation cost. The proposed converter presents also the possibility and the simplicity of changing the number of voltage levels only by acting on-line on the ratios of the desired output voltages. The modeling and control strategy of the proposed 31-level converter were verified by simulation. The good performance of the control strategy during steady state and transient regimes is reported.

In this paper, the authors present a novel competitive 31-level converter which makes use of small number of power switches and passive components. In case of DC/AC conversion, the proposed 31-level inverter allows a nearly sinusoidal output voltage resulting on a perfectly sinusoidal load current. In case of AC/DC conversion, it presents a reduced impact on the utility supply and a good energetic efficiency. An average model of the proposed converter is performed and a control strategy is designed in order to draw a nearly sinusoidal current and voltage. Active and passive filters can thus be avoided resulting on a highest energetic efficiency and a reduced installation cost. The proposed converter presents also the possibility and the simplicity of changing the number of voltage levels only by acting on-line on the ratios of the desired output voltages. The modeling and control strategy of the proposed 31-level converter were verified by simulation. The good performance of the control strategy during steady state and transient regimes is reported.

In this paper, authors propose a novel fourteen-band hysteresis technique to control the fifteen level packed U cells (PUC) converter. This topology was first introduced in [1]. It combines advantages of the flying capacitor and the cascaded H-bridge topologies. The study of the novel converter allows the establishment of the switches gates signals equations. In case of rectifier operation, the proposed fourteen-band controller is designed to draw a sinusoidal line current with a unity power factor. Harmonics contents of line current and rectifier input voltage are then very reduced which permits the reduction of the rating of active and passive filters resulting on a very high energetic efficiency and a reduced installation cost. The fifteen level PUC transformerless inverter has the advantage to operate with a single DC source. A fourteen-band technique is performed to control the auxiliary DC buses and to draw a nearly sinusoidal load current. The proposed concepts were verified by simulations performed in the Matlab Simulink and SimPowerSystem environments.

In this paper, authors propose a novel six-band hysteresis technique to control the seven level packed U cells (PUC) converter which was first introduced in [1]. This converter combines advantages of the flying capacitor and the cascaded H-bridge topologies. The study of the novel converter allows the establishment of the switches gates signals equations. In case of rectifier operation, the proposed six-band controller is designed to draw a sinusoidal line current (load current in case of inverter operation) with a unity power factor. Harmonics contents of line current (or load current) and rectifier input voltage (or inverter output voltage) are then very reduced which permits the reduction of the rating of active and passive filters resulting on a very high energetic efficiency and a reduced installation cost. The proposed concept was verified by simulations performed in the Matlab Simulink and SimPowerSystem environments.

In this paper, authors propose a six-band hysteresis vector controller based on the seven level packed U cells (PUC) converter to alleviate harmonics contents of stator voltages and currents of the induction machine. Active and passive filters rating can thus be significantly reduced resulting on a high energetic efficiency and a reduced installation cost. The PUC topology was first introduced in [1]. It combines advantages of the flying capacitor and the cascaded H-bridge topologies. In rectifier operation, the study of the novel converter allows the establishment of the switches gates signals equations leading to the proposed six-band controller which is designed to draw a sinusoidal line current with a unity power factor. Harmonics contents of line current and rectifier input voltage are then very reduced. The proposed concepts were verified by simulations performed in the Matlab Simulink and SimPowerSystem environments.

In this paper, authors propose a novel three phase seven level converter which results from a series connection of the new cascaded U cells and the neutral point clamped NPC topologies. A topological optimization of this configuration leads to the proposed scheme characterized by the use of only eight power switches per phase. Modeling, modulation and control technique of the proposed converter are performed in order to draw a nearly sinusoidal lines currents and line-to-line voltages. A method for balancing DC link output voltages is also proposed in order to protect loads, passives and actives power devices. The proposed three phase seven level converter with its control and balancing techniques were verified by simulation.

This paper proposes a strategy of control for multilevel converter that uses capacitors as auxiliary power source. Though this paper emphasis on the inverter control, the method has been proved effective for rectifier as well. In multi-level converter, the regulation of the capacitor is done on different switching state. Depending of the ratio between output and input voltage, two different mode of regulation are used. For a smaller ratio, less levels are necessary and a simple hysteresis is sufficient to achieve regulation. For a larger ratio, the drifting PWM is used, which allow a slight variation in the switching state so regulation can be acheive. Case study where both methods are required is simulated and then tested on a fast prototyping development board, to prove their reliability. Once fully functional, it is implemented on an FPGA board, making the embedded system more affordable. Using this method the output voltage should follow its reference, even when the input voltage changes.

A novel competitive fifteen level power converter is presented in this paper. The proposed scheme is characterized by the use of small number of power switches and passive components. It presents a reduced impact on the supply network in terms of harmonics and energetic efficiency. A control strategy based on an average model is performed and a linear control law is designed in order to draw a nearly sinusoidal line current. The use of the proposed converter reduces or even avoids utilization of active and passive filters which results on an optimized installation cost. The proposed converter presents also the possibility and the simplicity of changing the number of voltage levels only by acting on-line on the ratios of the desired output voltages. The modeling and control strategy of the proposed fifteen level converter were verified by simulation.

In this paper, authors presents a novel competitive multilevel converter. The novel cascaded U cells topology is constituted from two power switches and one capacitor for each cell. In case of DC/AC conversion, the proposed fifteen level inverter allows a nearly sinusoidal output voltage resulting on a perfectly sinusoidal load current. In case of AC/DC conversion, the proposed fifteen level rectifier presents a reduced impact on the utility supply, a good energetic efficiency and a small number of power switches and passive components. An average model of the proposed converter is performed and a control strategy is designed in order to draw a nearly sinusoidal current and voltage. Active and passive filters can thus be avoided resulting on a highest energetic efficiency and a reduced installation cost. The proposed converter presents also the possibility and the simplicity of changing the number of voltage levels only by acting online on the ratios of the desired output voltages. The modeling and control strategy of the proposed fifteen level converter were verified by simulation.

In this paper, authors propose an advanced five level rectifier which results from a series connection of two three level rectifiers. A topological optimization of this configuration leads to the proposed topology characterized by the use of only six power switches per phase. Modeling, modulation and control technique of the proposed rectifier are performed in order to draw a nearly sinusoidal lines currents and line-to-line voltages. A method for balancing DC link output voltages is also proposed in order to protect loads, passives and actives power devices. The proposed three phase five level rectifier with its control and balancing technique were verified by simulation.

In this paper, the authors propose a new technique applied to three level NPC rectifier which permits line currents and neutral point balancing while maintaining unity power factor operation. The idea of line current balancing is based on the symmetrical components theory. Indeed, In order to balance three phase line currents, the negative sequence component of line current references is eliminated. First, we compute for the active power component in synchronous reference frame, and then dq/abc transformation is applied to generate the equivalent line current references. These references are thereafter used to estimate both positive and negative sequences using the complex plan. An inverse transformation imposing zero negative sequence leads finally to balanced current references which are used to control the rectifier switches using SPWM. The obtained simulation results confirm the validity of the proposed algorithm in both steady state and dynamic regimes.