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Nowadays, the demand for power electronics technology has increased due to the importance of its applications such as power inverters. The power inverter is required to modify the DC power from PV cells to AC power. One of the most common issues of on-grid PV systems is the high variations of the generated DC voltage. This will affect the stability of the generated AC voltage at the Point of Common Coupling (PCC) with the grid. This paper combines the Feed-Forward and Feedback (FFFB) controller in a novel way to reduce the variation of the PV cells DC voltage. This paper presents both mathematical and Simulink models of single-phase voltage source inverters VSI. Then, a case study of 15% disturbance of DC-generated voltage is considered. The static and dynamic behaviour of the single-phase H-bridge inverter is analysed under different loads. The new combination is used to reduce the effect of the disturbance on the performance of the system. Also, the proposed closed-loop controller (FFFB) can reduce the overshoot by 50% less than the feedback controller only. The settling time has been improved by 41%, 61% for RL and induction motor.

The Internet of Things (IoT) introduces innovative real-time applications that use sensors to collect data that exchange between things to things and things to humans through the network. In this aspect, security and privacy is the primary concern for researchers to protect these systems. This paper proposes a real-time authentication algorithm based on the one-time pad (OTP) principle. The keys are dynamically exchanged, and the data is encrypted via dynamic encryption, depending on random sensors’ data. The key is generated and exchanged dynamically using the dynamic encryption technique, thus enhancing the users’ data privacy and security. Moreover, a lightweight key generation, exchange, and authentication protocol are proposed for data collecting from smart home sensors. The proposed protocol guarantees security and privacy demand, which are the user’s primary concern. The proposed protocol is developed for smart home applications with interfacing requirements, which makes the system real and applicable. The operation principle of the proposed protocol is illustrated sufficiently if there is any desynchronization or emergency.

DC-DC converters play a crucial role in recent and advanced applications, enabling efficient power conversion and management for renewable energy systems, electric vehicles, portable devices, and advanced communication systems. In line with this, the objective of this paper is to introduce a new DC-DC configuration based on the Cuk converter named as Mahafzah converter, which utilizes a coupling capacitor with a lower rated voltage. The paper aims to demonstrate the effectiveness of the proposed converter in terms of improved efficiency, reduced size, and reduced semiconductor device currents compared to the conventional Cuk converter. The proposed configuration comprises the same components as the Cuk converter, but in a different arrangement, without any additional elements. The main advantage of the proposed converter is using a coupling capacitor with a much lower rated voltage than the Cuk converter, resulting in a smaller capacitor size, reduced printed circuit board (PCB) size, and manufacturing cost. Additionally, the proposed converter reduces the currents of the semiconductor devices compared to those in the Cuk converter. To demonstrate its effectiveness, the converter is operated under continuous current mode (CCM) with a constant duty cycle and switching frequency. The study provides an in-depth discussion of the various operating modes by making use of equations relating to currents, voltages, duty cycles, and voltage gains. It also provides detailed illustrations of the limits between CCM and discontinuous current mode (DCM). The effectiveness of the proposed converter is demonstrated through a design example with operating parameters of 1 kW, 200 V/−300 V, and 20 kHz. Additionally, a low voltage–low power prototype (12/−18 V, 3.24 W, 20 kHz) is established to verify the operation of the proposed converter. Simulation and experimental verification of the proposed configuration achieved the desired results to improve efficiency and reduce the rate. The results clearly indicate that the efficiency of the proposed converter surpasses that of the conventional Cuk converter under identical operating conditions, reaching approximately 88% at rated load conditions.

Induction motors are commonly used in many different applications. The importance of these motors comes from their ruggedness, reliability, and low maintenance cost. Generally, the driving system of these motors can be vulnerable to injury of different types of faults during the operation, which leads to failure in continuous optimal operation of the system. This paper proposes a new simple algorithm to detect and classify the fault may occur in the driving system (in the Voltage Source Inverter VSI) of induction motor. The proposed method uses three parameters: First, the per phase average value of the stator current. Second, the Pulse Width Modulation (PWM) signal. Third, the switch voltage (drain to source voltage). The method is designed based on using the logic system. It is designed to decide whether the driving system is healthy or faulty. Moreover, the logic system can specify the fault location over the driving system. MATLAB 2020a is used to validate the results.

This paper explores the use of Space Vector Pulse Width Modulation (SVPWM) instead of Sinusoidal Pulse Width Modulation (SPWM) to evaluate dynamic response of the synchronous inverter (synchronverter). The paper presents a comprehensive comparison between the SVPWM and SPWM for the dynamic response of synchronverter. This comparison aspects contain: the grid frequency, the active and reactive power, line current and its THD and rate of change of frequency (RoCoF) in case of using both modulation techniques. Despite the complexity of using SVPWM, it has several advantages over SPWM. With the increased penetration of renewable energy sources in power systems, the system inertia is reduced, and the frequency deviations becomes greater and faster. The results of this paper show that SVPWM contributes to reducing the rate of change of frequency (RoCoF) which enhances the system inertia. The results show a more stable behavior of SVPWM than the SPWM. Moreover, SVPWM reduces the total harmonics distortion (THD) of the current by 7% as compared to SPWM. Furthermore, the use of SVPWM reduces the complexity and the cost of the used filter. Matlab/Simulink is used for results validation.

Artificial intelligence (AI) techniques are widely used in fault diagnosis because they are superior in detection and prediction. The detection of faults in power systems containing electronic components is critical. The switch faults of the voltage source inverter (VSI) have a severe impact on the driving system. Short-circuit switches increase the thermal stress due to their fast and high stator currents. Additionally, open-circuit switches cause unstable motor operation. However, these issues are not sufficiently addressed or accurately predicted for VSI switch faults in the literature. Thus, this paper investigates the use of different AI classifiers for three-phase VSI fault diagnosis. Various AI methods are used, such as naïve Bayes, support vector machine (SVM), artificial neural network (ANN), and decision tree (DT) techniques. These methods are applied to a VSI-fed permanent magnet synchronous motor (PMSM) to detect the faults in the inverter switches. These methods use the drain–source voltage and PWM signals to decide whether the switch is healthy or unhealthy. In addition, they are compared in terms of their detection accuracy. In this regard, the comparative results show that the DT method has the highest accuracy as compared to other methods in the fault diagnosis process. Moreover, this paper proposes a novel and universal voltage compensation loop to compensate for the absence of the voltage portion due to the open switch fault. Thus, the driving system is assisted in operating under its normal operating conditions. The universal term is used because the proposed voltage compensation loop can be implemented in any type of inverter. To validate the results, the proposed system is implemented using two software programs, LTSPICE XVII-USA, WEKA 3.9-New Zealand.

This paper proposes a new hybrid flyback-Cuk (HFC) converter. The new converter consists of a single switch, a single isolated input, and dual output based on flyback and Cuk topologies. The new HFC topology is proposed to reduce switching losses and improve the duty cycle range over which voltage can be stepped down, which would ultimately lead to an increase in efficiency. For step-down capability, the traditional single topologies (flyback or Cuk) require a less than 50% duty cycle. The low duty cycle of conventional converters leads to low operational efficiency. Therefore, the developed HFC can operate at a duty cycle of up to 85% for the same capability. The analysis, derivations, design, and simulation of the proposed HFC are thoroughly discussed for two different applications at two different power levels. The simulation results are obtained using MATLAB 2020a. The developed HFC’s efficiency as a function of the duty cycle is plotted, which reaches 89%, representing a significant efficiency improvement. The proposed converter can supply and absorb power simultaneously, giving it a significant edge over other converters. It is suitable for energy conversion and storage systems, such as renewable energy systems and electric vehicles (EV). To show the effectiveness and validate the new topology proposed, an EV along with battery energy storage (BES), is applied to charge (EV) and recharge (BES) simultaneously. The simulation results of 1.5 kW of HFC-PFC over the universal voltage range show that the proposed HFC can achieve a high power factor up to 97.5% at 260 Vrms. Moreover, the total harmonics distortion is measured between 36.25 and 27.69%. Thus, the results can achieve all required functions efficiently with minimum losses at a high range of duty cycles.

A novel step-up/step-down DC-DC converter with improved voltage gain characteristics is suggested in this paper. The proposed converter combines flyback and single-ended primary inductance converter (SEPIC) converters. The voltage control loop design is simplified due to the use of only a single controlled switch. It has been discussed how switch duty cycle affects voltage gain. This relationship demonstrates that the proposed converter voltage gain is improved compared with flyback and SEPIC converters. However, compared to flyback and SEPIC converters, it has a higher voltage gain at any given duty cycle. The proposed converter operation is thoroughly discussed, the associated equations are derived, and its parameters are expertly designed. Moreover, it is designed to supply a DC load of 2.5 kW, 500 V, and 5 A. The proposed converter efficiency exceeds 84% under rated load conditions. Additionally, it is also presented as an adapter for electric vehicles. The waveforms associated with the simulation of the converter across the universal line voltage of 110-260 Vrms are shown. At both line voltages, the total harmonics distortions (THDs) of the line current are 17.12% and 27.26%, respectively. MATLAB/Simulink is utilized for validation in order to validate the topology for different applications.

Induction motors are commonly used in different industrial, housing and medical applications, such as air conditioners, transportation, elevators and others. These motors are rugged, reliable and economical. Generally, the reliable operation of the motor and its drive system is very important in industry so that any expected fault must be detected immediately by a monitoring system. This paper reviews and simulates a three-phase induction motor model and different types of faults that may happen in the drive system. Due to short circuit severity on the overall drive system, this study focuses only on short circuit faults, e.g., when any Insulated Gate Bipolar Transistor (IGBT) is shorted out and DC link capacitor is shorted out. Also, an Adaptive Neuro Fuzzy Interface System (ANFIS) algorithm is programmed to detect different types of faults and classify them. The ANFIS system takes two parameters as input from the motor: the first one is the load torque whereas the second one is the stator current. Whereas, the previously published works analyze only the motor's stator current. MATLAB is used to train the ANFIS system and also to analyze samples. Additionally, LTSpice is used simulate the drive system. The ANFIS system shows very high accuracy in short circuit fault detection and classification.

This paper proposes a Single Ended Primary Inductance Converter Power Factor Correction circuit (SEPIC PFC). The proposed SEPIC PFC is operated in CRitical Conduction Mode (CRM) with Constant On Time (COT). Due to CRM operation, the SEPIC switch is turned on at Zero Current Switching (ZCS), thus, reducing the switching losses. A unity power factor of line current is nearly achieved, resulting in low Total Hrmonics Distortion (THD), over the universal line voltage (90V-260V). The simulation results show that the proposed design does have a smoothed line current and it is suitable for low power applications e.g., Laptops and mobiles chargers.