Differential mode Three-phase Micro inverter DTMI has many features in low voltage application su... more Differential mode Three-phase Micro inverter DTMI has many features in low voltage application such as module integrated PV architectures. It has the ability to increase the PV module voltage using single stage with low components count. Differential inverter is implemented using three DC-DC converters with their input terminals connected in parallel and their outputs terminals connected differentially to perform three-phase voltages. Isolated DC-DC converters such as Flyback, Cuk and SEPIC converters have imperative inherent features to be utilized in differential inverter such as high voltage gain and voltage isolation. Moreover, the wide voltage range provided by buck-boost feature and low Common Mode Voltage CMV is substantial for micro inverters. This paper introduces full performance analysis for the three candidate differential inverters. Basic features such as voltage gain, voltage stress, efficiency and number of components are compared and illustrated in details. Also, simulation results for the three candidates are demonstrated to conclude the principal features of each one.
In this paper, New asymmetric cascaded half H bridge multilevel inverter MLI is proposed. It is d... more In this paper, New asymmetric cascaded half H bridge multilevel inverter MLI is proposed. It is driven from the conventional asymmetric cascaded half H Bridge multilevel inverter. Thus, the proposed topology inherits its simplicity, flexibility and modularity in both construction and control. By proper choice of the input DC sources values and interconnection, proposed topology can eliminate the need for polarity generation circuit which normally associated with the cascaded half H-bridge. Therefore, reduces number of switches that require high blocking voltage. The selective harmonic elimination SHE method is applied to generate switching pattern to eliminate harmonics inherently associated with MLI. The proposed topology switching pattern naturally reduces component's voltage stress, switching losses and finally decrees MLI size and cost. Mathematical expressions and analysis have been driven as well as comparison with other topologies. The validity of the proposed topology is verified with Matlab/Simulink model and then a prototype is built and experimental results are presented.
PV systems have the drawbacks of high initial cost. The power electronics portions represents abo... more PV systems have the drawbacks of high initial cost. The power electronics portions represents about 50% of this cost for no-battery systems. Therefore, it is important to act to decrease this cost through designing a power conditioning circuit with lower cost. This paper proposes implementation of economic and efficient multilevel inverter for PV applications. Packed U Cell (PUC) multilevel inverter is employed as a competitive converter with minimum components compared to the existing ones. Boost DC-DC converter is designed to extract the maximum power point using P&O algorithm. Only six switches and single DC source (PV) are used to deliver a better power quality output in terms of number of voltage levels, low THD, small output filter. Simulink and experimental prototype are built to investigate the effectiveness of this topology. Results show a good matching.
In this paper, an enhanced version of whale optimization algorithm (EWOA) is presented to be appl... more In this paper, an enhanced version of whale optimization algorithm (EWOA) is presented to be applied in adaptive control techniques as a parameter tuner. One weakness point in this control scheme is the low efficiency of its objective function. Balloon effect (BE) is a modification introduced to increase the efficiency of the objective function of the optimization method and the ability of the controller to deal with system problems increase consequently. Controlling of the temperature of electric furnaces is considered as one of the important issues in several industrial applications. Conventional controllers such as PID controller cannot deal efficiently with the problem of parameters variations and step disturbance. This paper proposes an adaptive controller, in which the gain of the temperature controller is tuned online using EWOA supported by balloon effect. System responses obtained by the proposed adaptive control scheme using EWOA + BE have been compared with an electric fu...
Electrical power networks are expanded regularly to meet growing energy requirements. Reactive po... more Electrical power networks are expanded regularly to meet growing energy requirements. Reactive power dispatch (RPD) optimization is a powerful tool to enhance a system’s efficiency, reliability, and security. RPD optimization is classified as a non-linear and non-convex problem. In this paper, the RPD optimization problem is solved based on novel hybrid genetic algorithms—equilibrium optimizer (GAEO) optimization algorithms. The control variables are determined in such a way that optimizes RPD and minimizes power losses. The efficiency of the proposed optimization algorithms is compared to other techniques that have been used recently to solve the RPD problem. The proposed algorithm has been tested for optimization RPD for three test systems, IEEE14-bus, IEEE-30bus, and IEEE57-bus. The obtained results show the superiority of GAEO over other techniques for small test systems, IEEE14-bus and IEEE-30bus. GAEO shows good results for large system, IEEE 57-bus.
A static VAR compensator (SVC) is a critical component for reactive power compensation in electri... more A static VAR compensator (SVC) is a critical component for reactive power compensation in electric arc furnaces (EAFs) that is used to relieve the flicker impacts and maintain the voltage level. A weak voltage profile can not only reduce the power-quality services, but can also result in system instability in severe cases. The cybersecurity of EAFs is becoming a significant concern due to their cyber-physical structure. The reliance of SVC controllers on reactive power measurement and network communications has resulted in a cyber-vulnerability point for unauthorized access to the EAF, which can affect its normal operation. This paper addresses concerns about cyber attacks on EAFs, which can cause network communication issues in measurement data for SVCs. Three significant and different types of cyber attacks that are launched on SVC controllers—a replay attack, delay attack, and false data injection attack (FDIA)—were simulated and investigated. In order to stop the activities of c...
When a photovoltaic (PV) system is exposed to physical objects and cloud coverage and connected t... more When a photovoltaic (PV) system is exposed to physical objects and cloud coverage and connected to bypass diodes, a partial shading condition (PSC) occurs, which causes a global maximum power point (GMPP) and numerous local maximum power points (LMPPs) on the power-voltage (P-V) curve. Unlike conventional MPPT techniques that search for multiple LMPPs on the P-V curve, it is possible to track GMPP straightaway by designing a simple but robust MPPT technique that results in faster tracking speed and low power oscillations. Hence, in this study, an improved proportional-integral (PI) coordinated Maximum Power Point Tracking (MPPT) algorithm is designed to enhance the conversion efficiency of a PV system under PSC with fast-tracking speed and reduced power oscillations. Here, PI controllers are used to mitigating the steady-state errors of output voltage and current of PV system that later on passed through an incremental conductance (INC) algorithm to regulate the duty cycle of a dc–d...
The main aim of this work was the maximization of the energy saving of balanced and unbalanced di... more The main aim of this work was the maximization of the energy saving of balanced and unbalanced distribution power systems via system reconfiguration and the optimum capacitor’s bank choice, which were estimated by using a new algorithm: modified Tabu search and Harper sphere search (MTS-HSSA). The results demonstrated that the proposed method is appropriate for energy saving and improving performance compared with other methods reported in the literature for IEEE 33-bus adopted systems, including large scale systems such as IEEE 119 and the IEEE 123 unbalanced distribution system. Moreover, it can be used for unbalanced distribution systems distributed generators (DGs). The results demonstrated that the proposed method (the optimal choice of shunt capacitor (SC) banks and the optimal reconfiguration via the proposed algorithm) is appropriate for energy saving compared with different strategies for energy saving, which included distributed generation (DG) at different cost levels.
Unit commitment problem (UCP) is classified as a mixed-integer, large combinatorial, high-dimensi... more Unit commitment problem (UCP) is classified as a mixed-integer, large combinatorial, high-dimensional and nonlinear optimization problem. This paper suggests solving the UCP under deterministic and stochastic load demand using a hybrid technique that includes the modified particle swarm optimization (MPSO) along with equilibrium optimizer (EO), termed as MPSO-EO. The proposed approach is tested firstly on 15 benchmark test functions, and then it is implemented to solve the UCP under two test systems. The results are basically compared to that of standard EO and previously applied optimization techniques in solving the UCP. In test system 1, the load demand is deterministic. The proposed technique is in the best three solutions for the 10-unit system with cost savings of 309.95 USD over standard EO and for the 20-unit system it shows the best results over all algorithms in comparison with cost savings of 1951.5 USD over standard EO. In test system 2, the load demand is considered sto...
This paper proposes a three-phase 7 levels voltage source inverter employing space vector modulat... more This paper proposes a three-phase 7 levels voltage source inverter employing space vector modulation (SVM) control scheme and with natural dc bus voltages balancing. The proposed inverter is a modular type that can increase its level by adding more cells to each arm. A high frequency transformer (HFT) is proposed in this paper to generate the dc bus voltage of the auxiliary cell from the main cell dc bus voltage. As a result of that the number of isolated dc bus voltages required is reduced by half. In addition, a natural balancing between the main and auxiliary cell dc bus voltages of each arm will be attained due to the HFT turns ratio which result in simplifying the overall control of the whole system. In order to reduce the size of the HFT a judicious modulation index (MI) will be chosen. The proposed system has been simulated using induction motor load. Analyses and simulation have been provided to validate the proposed system. Index Term— MLI, Isolated DC bus sources, HFT, SVM...
This paper presents a new approach of control algorithm for single phase inverter with minimum ha... more This paper presents a new approach of control algorithm for single phase inverter with minimum harmonics values. Minimum harmonics is based on elimination of selected low order harmonics. The calculated switching angles are utilized in the control algorithm which is simply written in matlab using m-file to finally generate inverter switches pulses. The code is very simple and it is written in C-language very close to that written in the experimental results. The low order harmonics up to the 21 are eliminated. An LC filter with low size is utilized leading to full elimination of low and high order harmonics. Implementation of the system is carried out and an inexpensive dspic30F2010 microcontroller is used resulting in extremely reduction in hardware complexity. Experimental results verify the effectiveness of the proposed inverter and they are very close to simulation results. Keywords— Harmonics Elimination, Switching Angles, Filter.
This paper presents the computation of the cable ampacity and the temperature distribution throug... more This paper presents the computation of the cable ampacity and the temperature distribution through long duration based on the equivalent thermal circuit based on IEC 60287 standard and the Finite element method using COMSOL (Multiphysics environment, version 5.5). This study investigated the cable ampacity and the temperature rise of the cable core and sheath at steady state and emergency conditions. The cable ampacity was investigated at different conditions such as the variation of cable depth, soil properties, and soil temperature. The results confirmed the adaptation between the thermal circuit results and the COMSOL results as well as the effectiveness of using the numerical method to compute the cable ampacity. Using the COMSOL-based thermal properties evaluations, the transient performance of the cable is ascertained. The transient study is performed for different cable loading currents and dry zone sizes.
Energy demand has been overgrowing in developing countries. Moreover, the fluctuation of fuel pri... more Energy demand has been overgrowing in developing countries. Moreover, the fluctuation of fuel prices is a primary concern faced by many countries that highly rely on conventional power generation to meet the load demand. Hence, the need to use alternative resources, such as renewable energy, is crucial in order to mitigate fossil fuel dependency, while ensuring reductions in carbon dioxide emissions. Algeria—being the largest county in Africa—has experienced a rapid growth in energy demand over the past decade due to the significant increase in residential, commercial, and industry sectors. Currently, the hydrocarbon-rich nation is highly dependent on fossil fuels for electricity generation, with renewable energy only having a small contribution to the country’s energy mix. However, the country has massive potential for renewable energy generation, such as solar, wind, biomass, geothermal, and hydropower. Therefore, the government aims to diversify away from fossil fuels and promote...
Automatic voltage regulators (AVRs) in electrical grids preserve the voltage at its nominal value... more Automatic voltage regulators (AVRs) in electrical grids preserve the voltage at its nominal value. Regulating the parameters of proportional-integralderivative (PID) controllers used for AVRs is a nonlinear optimization issue. The objective function is designed to minimize the settling time, rise time, and overshoot of step response of resultant voltage with subjugation to constraints of PID controller parameters. In this study, we suggest using an Archimedes optimization algorithm (AOA) to tune the parameters of the PID controllers for AVRs. In addition, using an AOA to optimize the parameters of a fractional-order PID (FOPID) controller and a PID plus second-order derivative (PIDD 2) controller for AVRs is also investigated to validate their effectiveness. The disturbance repudiation and robustness of the AOA-PID controllers are also examined and confirmed. To validate the results of the AOA-PID controllers, they are compared with those of other optimized controllers for convergence speed, the quality of the step response. The results indicate that the AOA functions perfectly and it has good potential for optimizing the PID controller parameters with better step response compared with the PID controller based on other approaches while preferring the results of the AOA-PIDD 2 controller over other kinds of the AOA-PID controllers.
Recently, most transportation systems have used an integrated electrical machine in their tractio... more Recently, most transportation systems have used an integrated electrical machine in their traction scheme, resulting in a hybrid electrified vehicle. As a result, an energy source is required to provide the necessary electric power to this traction portion. However, this cannot be efficient without a reliable recharging method and a practical solution. This study discusses the wireless recharge solutions and tests the system’s effectiveness under various external and internal conditions. Moreover, the Maxwell tool is used in this research to provide a complete examination of the coils’ position, size, number, and magnetic flux evolution when the coils are translated. In addition, the mutual inductance for each of these positions is computed to determine the ideal conditions for employing the wireless recharge tool for every charging application. A thorough mathematical analysis is also presented, and the findings clearly demonstrate the relationship between the magnet flux and the v...
The paper is concerned with designing an effective controller for a linear tubular homopolar (LT-... more The paper is concerned with designing an effective controller for a linear tubular homopolar (LT-H) motor type. The construction and operation of the LT-H motor are first described in detail. Then, the motor model is represented in the direct-quadrature (d-q) axes in order to facilitate the design of the control loops. The designed control system consists of two main loops: the current control loop and velocity adaptation loop. The determination of the regulator’s gains is accomplished through deriving and analyzing the transfer functions of the loops. To enhance the system’s robustness, a robust variable estimator is designed to observe the velocity and stator resistance. Different performance evaluation tests are performed using MATLAB/Simulink software to validate the controller’s robustness for variable-speed operation and load force changes as well. The obtained results reveal the appropriate dynamics of the motor thanks to the well-designed control system.
International Journal of Power Electronics and Drive Systems (IJPEDS), 2018
This paper proposes an asymmetrical cascaded single phase H-bridge inverter. The proposed inverte... more This paper proposes an asymmetrical cascaded single phase H-bridge inverter. The proposed inverter consists of two modules with unequal and isolated dc sources. Each module is composed of dc source, conventional four switches H-bridge and single bidirectional switch. To increase the output voltage levels, the tertiary ratio, 1:3, between its two dc sources is adopted. Both the fundamental frequency and the multicarrier pulse width modulation (PWM) control schemes are employed to generate switches signals. By controlling the inverter modulation index, the proposed inverter can generate an output voltage having up to seventeen levels by using only two modules. The proposed topology has also the feature of modularity which means that it can be extended to any levels by adding new modules. The proposed topology is simulated using an inductive load and some selected simulation results have been provided to validate the proposed inverter.
IEEE Journal of Emerging and Selected Topics in Power Electronics, 2019
This paper proposes a general mathematical solution for a selected harmonic elimination (SHE) tec... more This paper proposes a general mathematical solution for a selected harmonic elimination (SHE) technique. The proposed procedure is valid for both symmetrical and unsymmetrical MLI inverter configurations with a wide range of modulation indexes (mi). The proposed procedure eliminates targeted number of harmonics 'l ' for switching angles NS= 2l regardless to the MLI output waveform levels. The proposed procedure receives the DC sources values and ratios, and then it calculates the NS values to generate a suitable set of harmonic equations. In this proposed algorithm, the nonlinear transcendental harmonic equations were transformed into a linear system of equations (A X=B); the resulting equations can be solved online easily by formulating matrix A and matrix B, then multiplying the inversion of matrix A in matrix B. It has been found that, only the last element in matrix B needs to be updated for each change in modulation index or in the ac output fundamental component, resulting in reduced computation time. The proposed technique generates the switching angles 1,2,...,k based on a preset objective functions. The simulation and experimental results in some selected cases are provided to validate the proposed algorithms.
Journal of Electrical Systems and Information Technology, 2018
This paper presents theoretical analysis and experimental implementation of a classical controlle... more This paper presents theoretical analysis and experimental implementation of a classical controller with intelligent properties. The controller has constant parameters, but it performs as an intelligent controller. The controller design mimics the fuzzy logic controller in a classical form and combines the advantages of classical controllers and properties of intelligent controllers. The designed controller parameters force the controlled variable to behave such as a first order system with a desired time constant. DC motor practical system is used to demonstrate the effectiveness of the presented controller. Root locus and frequency response using Bode diagram are used to help the design of the controller parameters. Simulation and experimental results verify the high performance of the presented controller.
Differential mode Three-phase Micro inverter DTMI has many features in low voltage application su... more Differential mode Three-phase Micro inverter DTMI has many features in low voltage application such as module integrated PV architectures. It has the ability to increase the PV module voltage using single stage with low components count. Differential inverter is implemented using three DC-DC converters with their input terminals connected in parallel and their outputs terminals connected differentially to perform three-phase voltages. Isolated DC-DC converters such as Flyback, Cuk and SEPIC converters have imperative inherent features to be utilized in differential inverter such as high voltage gain and voltage isolation. Moreover, the wide voltage range provided by buck-boost feature and low Common Mode Voltage CMV is substantial for micro inverters. This paper introduces full performance analysis for the three candidate differential inverters. Basic features such as voltage gain, voltage stress, efficiency and number of components are compared and illustrated in details. Also, simulation results for the three candidates are demonstrated to conclude the principal features of each one.
In this paper, New asymmetric cascaded half H bridge multilevel inverter MLI is proposed. It is d... more In this paper, New asymmetric cascaded half H bridge multilevel inverter MLI is proposed. It is driven from the conventional asymmetric cascaded half H Bridge multilevel inverter. Thus, the proposed topology inherits its simplicity, flexibility and modularity in both construction and control. By proper choice of the input DC sources values and interconnection, proposed topology can eliminate the need for polarity generation circuit which normally associated with the cascaded half H-bridge. Therefore, reduces number of switches that require high blocking voltage. The selective harmonic elimination SHE method is applied to generate switching pattern to eliminate harmonics inherently associated with MLI. The proposed topology switching pattern naturally reduces component's voltage stress, switching losses and finally decrees MLI size and cost. Mathematical expressions and analysis have been driven as well as comparison with other topologies. The validity of the proposed topology is verified with Matlab/Simulink model and then a prototype is built and experimental results are presented.
PV systems have the drawbacks of high initial cost. The power electronics portions represents abo... more PV systems have the drawbacks of high initial cost. The power electronics portions represents about 50% of this cost for no-battery systems. Therefore, it is important to act to decrease this cost through designing a power conditioning circuit with lower cost. This paper proposes implementation of economic and efficient multilevel inverter for PV applications. Packed U Cell (PUC) multilevel inverter is employed as a competitive converter with minimum components compared to the existing ones. Boost DC-DC converter is designed to extract the maximum power point using P&O algorithm. Only six switches and single DC source (PV) are used to deliver a better power quality output in terms of number of voltage levels, low THD, small output filter. Simulink and experimental prototype are built to investigate the effectiveness of this topology. Results show a good matching.
In this paper, an enhanced version of whale optimization algorithm (EWOA) is presented to be appl... more In this paper, an enhanced version of whale optimization algorithm (EWOA) is presented to be applied in adaptive control techniques as a parameter tuner. One weakness point in this control scheme is the low efficiency of its objective function. Balloon effect (BE) is a modification introduced to increase the efficiency of the objective function of the optimization method and the ability of the controller to deal with system problems increase consequently. Controlling of the temperature of electric furnaces is considered as one of the important issues in several industrial applications. Conventional controllers such as PID controller cannot deal efficiently with the problem of parameters variations and step disturbance. This paper proposes an adaptive controller, in which the gain of the temperature controller is tuned online using EWOA supported by balloon effect. System responses obtained by the proposed adaptive control scheme using EWOA + BE have been compared with an electric fu...
Electrical power networks are expanded regularly to meet growing energy requirements. Reactive po... more Electrical power networks are expanded regularly to meet growing energy requirements. Reactive power dispatch (RPD) optimization is a powerful tool to enhance a system’s efficiency, reliability, and security. RPD optimization is classified as a non-linear and non-convex problem. In this paper, the RPD optimization problem is solved based on novel hybrid genetic algorithms—equilibrium optimizer (GAEO) optimization algorithms. The control variables are determined in such a way that optimizes RPD and minimizes power losses. The efficiency of the proposed optimization algorithms is compared to other techniques that have been used recently to solve the RPD problem. The proposed algorithm has been tested for optimization RPD for three test systems, IEEE14-bus, IEEE-30bus, and IEEE57-bus. The obtained results show the superiority of GAEO over other techniques for small test systems, IEEE14-bus and IEEE-30bus. GAEO shows good results for large system, IEEE 57-bus.
A static VAR compensator (SVC) is a critical component for reactive power compensation in electri... more A static VAR compensator (SVC) is a critical component for reactive power compensation in electric arc furnaces (EAFs) that is used to relieve the flicker impacts and maintain the voltage level. A weak voltage profile can not only reduce the power-quality services, but can also result in system instability in severe cases. The cybersecurity of EAFs is becoming a significant concern due to their cyber-physical structure. The reliance of SVC controllers on reactive power measurement and network communications has resulted in a cyber-vulnerability point for unauthorized access to the EAF, which can affect its normal operation. This paper addresses concerns about cyber attacks on EAFs, which can cause network communication issues in measurement data for SVCs. Three significant and different types of cyber attacks that are launched on SVC controllers—a replay attack, delay attack, and false data injection attack (FDIA)—were simulated and investigated. In order to stop the activities of c...
When a photovoltaic (PV) system is exposed to physical objects and cloud coverage and connected t... more When a photovoltaic (PV) system is exposed to physical objects and cloud coverage and connected to bypass diodes, a partial shading condition (PSC) occurs, which causes a global maximum power point (GMPP) and numerous local maximum power points (LMPPs) on the power-voltage (P-V) curve. Unlike conventional MPPT techniques that search for multiple LMPPs on the P-V curve, it is possible to track GMPP straightaway by designing a simple but robust MPPT technique that results in faster tracking speed and low power oscillations. Hence, in this study, an improved proportional-integral (PI) coordinated Maximum Power Point Tracking (MPPT) algorithm is designed to enhance the conversion efficiency of a PV system under PSC with fast-tracking speed and reduced power oscillations. Here, PI controllers are used to mitigating the steady-state errors of output voltage and current of PV system that later on passed through an incremental conductance (INC) algorithm to regulate the duty cycle of a dc–d...
The main aim of this work was the maximization of the energy saving of balanced and unbalanced di... more The main aim of this work was the maximization of the energy saving of balanced and unbalanced distribution power systems via system reconfiguration and the optimum capacitor’s bank choice, which were estimated by using a new algorithm: modified Tabu search and Harper sphere search (MTS-HSSA). The results demonstrated that the proposed method is appropriate for energy saving and improving performance compared with other methods reported in the literature for IEEE 33-bus adopted systems, including large scale systems such as IEEE 119 and the IEEE 123 unbalanced distribution system. Moreover, it can be used for unbalanced distribution systems distributed generators (DGs). The results demonstrated that the proposed method (the optimal choice of shunt capacitor (SC) banks and the optimal reconfiguration via the proposed algorithm) is appropriate for energy saving compared with different strategies for energy saving, which included distributed generation (DG) at different cost levels.
Unit commitment problem (UCP) is classified as a mixed-integer, large combinatorial, high-dimensi... more Unit commitment problem (UCP) is classified as a mixed-integer, large combinatorial, high-dimensional and nonlinear optimization problem. This paper suggests solving the UCP under deterministic and stochastic load demand using a hybrid technique that includes the modified particle swarm optimization (MPSO) along with equilibrium optimizer (EO), termed as MPSO-EO. The proposed approach is tested firstly on 15 benchmark test functions, and then it is implemented to solve the UCP under two test systems. The results are basically compared to that of standard EO and previously applied optimization techniques in solving the UCP. In test system 1, the load demand is deterministic. The proposed technique is in the best three solutions for the 10-unit system with cost savings of 309.95 USD over standard EO and for the 20-unit system it shows the best results over all algorithms in comparison with cost savings of 1951.5 USD over standard EO. In test system 2, the load demand is considered sto...
This paper proposes a three-phase 7 levels voltage source inverter employing space vector modulat... more This paper proposes a three-phase 7 levels voltage source inverter employing space vector modulation (SVM) control scheme and with natural dc bus voltages balancing. The proposed inverter is a modular type that can increase its level by adding more cells to each arm. A high frequency transformer (HFT) is proposed in this paper to generate the dc bus voltage of the auxiliary cell from the main cell dc bus voltage. As a result of that the number of isolated dc bus voltages required is reduced by half. In addition, a natural balancing between the main and auxiliary cell dc bus voltages of each arm will be attained due to the HFT turns ratio which result in simplifying the overall control of the whole system. In order to reduce the size of the HFT a judicious modulation index (MI) will be chosen. The proposed system has been simulated using induction motor load. Analyses and simulation have been provided to validate the proposed system. Index Term— MLI, Isolated DC bus sources, HFT, SVM...
This paper presents a new approach of control algorithm for single phase inverter with minimum ha... more This paper presents a new approach of control algorithm for single phase inverter with minimum harmonics values. Minimum harmonics is based on elimination of selected low order harmonics. The calculated switching angles are utilized in the control algorithm which is simply written in matlab using m-file to finally generate inverter switches pulses. The code is very simple and it is written in C-language very close to that written in the experimental results. The low order harmonics up to the 21 are eliminated. An LC filter with low size is utilized leading to full elimination of low and high order harmonics. Implementation of the system is carried out and an inexpensive dspic30F2010 microcontroller is used resulting in extremely reduction in hardware complexity. Experimental results verify the effectiveness of the proposed inverter and they are very close to simulation results. Keywords— Harmonics Elimination, Switching Angles, Filter.
This paper presents the computation of the cable ampacity and the temperature distribution throug... more This paper presents the computation of the cable ampacity and the temperature distribution through long duration based on the equivalent thermal circuit based on IEC 60287 standard and the Finite element method using COMSOL (Multiphysics environment, version 5.5). This study investigated the cable ampacity and the temperature rise of the cable core and sheath at steady state and emergency conditions. The cable ampacity was investigated at different conditions such as the variation of cable depth, soil properties, and soil temperature. The results confirmed the adaptation between the thermal circuit results and the COMSOL results as well as the effectiveness of using the numerical method to compute the cable ampacity. Using the COMSOL-based thermal properties evaluations, the transient performance of the cable is ascertained. The transient study is performed for different cable loading currents and dry zone sizes.
Energy demand has been overgrowing in developing countries. Moreover, the fluctuation of fuel pri... more Energy demand has been overgrowing in developing countries. Moreover, the fluctuation of fuel prices is a primary concern faced by many countries that highly rely on conventional power generation to meet the load demand. Hence, the need to use alternative resources, such as renewable energy, is crucial in order to mitigate fossil fuel dependency, while ensuring reductions in carbon dioxide emissions. Algeria—being the largest county in Africa—has experienced a rapid growth in energy demand over the past decade due to the significant increase in residential, commercial, and industry sectors. Currently, the hydrocarbon-rich nation is highly dependent on fossil fuels for electricity generation, with renewable energy only having a small contribution to the country’s energy mix. However, the country has massive potential for renewable energy generation, such as solar, wind, biomass, geothermal, and hydropower. Therefore, the government aims to diversify away from fossil fuels and promote...
Automatic voltage regulators (AVRs) in electrical grids preserve the voltage at its nominal value... more Automatic voltage regulators (AVRs) in electrical grids preserve the voltage at its nominal value. Regulating the parameters of proportional-integralderivative (PID) controllers used for AVRs is a nonlinear optimization issue. The objective function is designed to minimize the settling time, rise time, and overshoot of step response of resultant voltage with subjugation to constraints of PID controller parameters. In this study, we suggest using an Archimedes optimization algorithm (AOA) to tune the parameters of the PID controllers for AVRs. In addition, using an AOA to optimize the parameters of a fractional-order PID (FOPID) controller and a PID plus second-order derivative (PIDD 2) controller for AVRs is also investigated to validate their effectiveness. The disturbance repudiation and robustness of the AOA-PID controllers are also examined and confirmed. To validate the results of the AOA-PID controllers, they are compared with those of other optimized controllers for convergence speed, the quality of the step response. The results indicate that the AOA functions perfectly and it has good potential for optimizing the PID controller parameters with better step response compared with the PID controller based on other approaches while preferring the results of the AOA-PIDD 2 controller over other kinds of the AOA-PID controllers.
Recently, most transportation systems have used an integrated electrical machine in their tractio... more Recently, most transportation systems have used an integrated electrical machine in their traction scheme, resulting in a hybrid electrified vehicle. As a result, an energy source is required to provide the necessary electric power to this traction portion. However, this cannot be efficient without a reliable recharging method and a practical solution. This study discusses the wireless recharge solutions and tests the system’s effectiveness under various external and internal conditions. Moreover, the Maxwell tool is used in this research to provide a complete examination of the coils’ position, size, number, and magnetic flux evolution when the coils are translated. In addition, the mutual inductance for each of these positions is computed to determine the ideal conditions for employing the wireless recharge tool for every charging application. A thorough mathematical analysis is also presented, and the findings clearly demonstrate the relationship between the magnet flux and the v...
The paper is concerned with designing an effective controller for a linear tubular homopolar (LT-... more The paper is concerned with designing an effective controller for a linear tubular homopolar (LT-H) motor type. The construction and operation of the LT-H motor are first described in detail. Then, the motor model is represented in the direct-quadrature (d-q) axes in order to facilitate the design of the control loops. The designed control system consists of two main loops: the current control loop and velocity adaptation loop. The determination of the regulator’s gains is accomplished through deriving and analyzing the transfer functions of the loops. To enhance the system’s robustness, a robust variable estimator is designed to observe the velocity and stator resistance. Different performance evaluation tests are performed using MATLAB/Simulink software to validate the controller’s robustness for variable-speed operation and load force changes as well. The obtained results reveal the appropriate dynamics of the motor thanks to the well-designed control system.
International Journal of Power Electronics and Drive Systems (IJPEDS), 2018
This paper proposes an asymmetrical cascaded single phase H-bridge inverter. The proposed inverte... more This paper proposes an asymmetrical cascaded single phase H-bridge inverter. The proposed inverter consists of two modules with unequal and isolated dc sources. Each module is composed of dc source, conventional four switches H-bridge and single bidirectional switch. To increase the output voltage levels, the tertiary ratio, 1:3, between its two dc sources is adopted. Both the fundamental frequency and the multicarrier pulse width modulation (PWM) control schemes are employed to generate switches signals. By controlling the inverter modulation index, the proposed inverter can generate an output voltage having up to seventeen levels by using only two modules. The proposed topology has also the feature of modularity which means that it can be extended to any levels by adding new modules. The proposed topology is simulated using an inductive load and some selected simulation results have been provided to validate the proposed inverter.
IEEE Journal of Emerging and Selected Topics in Power Electronics, 2019
This paper proposes a general mathematical solution for a selected harmonic elimination (SHE) tec... more This paper proposes a general mathematical solution for a selected harmonic elimination (SHE) technique. The proposed procedure is valid for both symmetrical and unsymmetrical MLI inverter configurations with a wide range of modulation indexes (mi). The proposed procedure eliminates targeted number of harmonics 'l ' for switching angles NS= 2l regardless to the MLI output waveform levels. The proposed procedure receives the DC sources values and ratios, and then it calculates the NS values to generate a suitable set of harmonic equations. In this proposed algorithm, the nonlinear transcendental harmonic equations were transformed into a linear system of equations (A X=B); the resulting equations can be solved online easily by formulating matrix A and matrix B, then multiplying the inversion of matrix A in matrix B. It has been found that, only the last element in matrix B needs to be updated for each change in modulation index or in the ac output fundamental component, resulting in reduced computation time. The proposed technique generates the switching angles 1,2,...,k based on a preset objective functions. The simulation and experimental results in some selected cases are provided to validate the proposed algorithms.
Journal of Electrical Systems and Information Technology, 2018
This paper presents theoretical analysis and experimental implementation of a classical controlle... more This paper presents theoretical analysis and experimental implementation of a classical controller with intelligent properties. The controller has constant parameters, but it performs as an intelligent controller. The controller design mimics the fuzzy logic controller in a classical form and combines the advantages of classical controllers and properties of intelligent controllers. The designed controller parameters force the controlled variable to behave such as a first order system with a desired time constant. DC motor practical system is used to demonstrate the effectiveness of the presented controller. Root locus and frequency response using Bode diagram are used to help the design of the controller parameters. Simulation and experimental results verify the high performance of the presented controller.
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Papers by Mahrous Ahmed