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To face the challenges raised by the qualification of metallic additively manufactured (AM) complex shaped and rough finish parts, non-destructive testing (NDT) volumetric methods are required. X-ray computed tomography (XCT) is presently the favored technique; however, alternative methods are needed to overcome the requirement of technical skills and the high cost of the technique. XCT also has limitations regarding the size and density of parts. Here, we propose an easy to use, fast, and efficient global NDT volumetric method based on resonant ultrasound spectroscopy (RUS) which basic principle relies on the comparative analysis of natural resonant frequency spectra of similar parts from the same family, both of which vibrating as free as possible. The methods have already proven to have the ability to sort parts with defects from flawless parts. In the present study, we demonstrate that RUS can also segregate metallic parts manufactured with different AM system process parameters. Eleven sets of three parts were manufactured, using a metal laser-powder bed fusion process, with different wall thicknesses, laser powers, scanning speeds, and scanning strategies. These parts were tested by RUS and then analyzed using the Z-score statistical method. The AM process parameter changes clearly influenced the resonance responses of the parts, and thus, the method is able to classify the different groups of parts according to their process parameters. Hence, the RUS methods can provide industries convenient tools to not only identify defective parts but to also configure AM machine parameters according to the expected and desired material properties.

A circulating-current-excited switched reluctance generator system using a standard diode rectifier is proposed and examined in this paper. It features a DC power source connected in series with the ring-connected windings, which provides the DC-bias current as the excitation current in the windings. Using a series-connected DC power source, a DC-bias current is easily realized in the AC winding. Compared to the existing machine having DC-bias in the AC winding, the proposed generator can provide DC power with a standard diode rectifier. Less active legs and no rotor position sensor are needed for the control of the circulating current of the proposed generator, which increases the reliability of the generation system. The system configuration and the operation principle are introduced in detail. Then, the electromagnetic performance of the proposed generation system is analyzed at both open-circuit and load conditions. The asymmetric current distributions are deduced and verified by the simulations. At last, the prototype is tested under varied operation conditions and the experiments agree well with the analysis.

The present paper focuses on embedded electrical networks (EEN) under electrical fault conditions. Indeed, the EEN can be affected by small or large disturbances, such as a low voltage ride through or a short-circuit in distribution or consumption parts of the embedded network. In fact, these problems can lead to the network instability and also affect the efficiency of marine vessels. In this work, the EEN can be converted into a flexible network by implementing the dynamic compensation devices. These devices can be considered as a synchronous machine that exchanges only the reactive power with EEN. Indeed, this compensation equipment entitled “Flexible AC Transmission System (FACTS)”, and it is used to improve the dynamic voltage stability of EEN. In this paper, the electrical network performances on the marine vessels are improved when the EEN is affected by small or large disturbances. Moreover, these improvements are achieved by integrating the automatic voltage regulator for ensuring the transient voltage stability, while the static VAr compensator (SVC) and static synchronous compensator (STATCOM) are implemented on the bus-bar of EEN to improve the dynamic voltage stability of the electrical network. The results of this study are obtained by using “Simulink/Matlab” software and a comparative analysis between the efficiency of SVC and STATCOM devices on the EEN stability is also presented.

Modular-multilevel converters (MMCs) are considered a useful technology in high-voltage direct current (hvdc) transmission systems. Since it offers many advantages like modular configuration with scalable output voltage. Voltage ripples on sub-module (SM) capacitors in MMC and circulating currents are two major challenges, which can affect the converter stability and performance. Conventionally, direct modulation method is used to insert or bypass SMs in MMC producing circulating current and SMs capacitor voltage oscillations. The closed loop and open loop control methods are used to overcome drawbacks in direct modulation method. However, these methods rely on the accurate measurements and estimation of SM capacitor voltages. A flat bottom current method is proposed in this paper to minimize the amplitude of ripple voltages on SM capacitors in MMC-based HVDC systems. Limited capacitor energy changes leading to reduce capacitor voltage ripples are observed by the proposed methodology using direct-modulation method without using circulating current suppression controller. The proposed method is tested on a two-terminal MMC-based HVDC system implemented by vector control approach in PSCAD/EMTDC software. Analytical results are verified by simulation results in reducing capacitor voltage ripples based on the direct modulation approach.

This paper is intended to solve a detail in the precautions to avoid the spreading of the coronavirus. Indeed, spreading by contact could lead to a new outbreak of the epidemic and a return of coronavirus. Two applied means to avoid the spread of COVID-19 are wearing masks and using an alcohol gel dispenser. In this paper, a non-contact automatic alcohol gel dispensed (AAGD) is proposed. This device is based on microcontroller device “Arduino Nano”, Ultrasonic sensor “HC-SR05” and servo-motor of 1 Nm. It can be used and integrated in the schools, markets, and different companies. In this focus, the AAGD works without touching by hand that could have touched the nose and not cleaned 100%. This property is important in this crisis period, especially since the appearance of coronavirus delta variant. This real-time device is nice to operate, and could be produced using quite common control devices, a too high or complicated technology level would reduce its application.

A new structure of a linear switched reluctance motor is proposed in this paper. With the permanent magnet inserted in the movers, the performance of the original motor is improved. An electromagnetic analysis is done by using the finite element analysis. The influence of the permanent magnets in different positions of the movers on the electromagnetic force is investigated. Furthermore, a theoretical analysis is made, based on the Schwarz–Christoffel transformation and the Maxwell stress tensor method. The mathematic model is also made with the consideration of the end effect and the cogging effect. The theoretical result of the electromagnetic force is compared with the simulation result. The comparison shows that the error is limited. The analysis of the flux, the magnetic field, and the inductance is then made. The results confirm that the new structure makes the motor more linearized. The new structure of linear switched reluctance motor can contribute to reducing the ripple in the electromagnetic force.

In this paper, a single-phase photovoltaic (PV) inverter fed by a boost converter to supply a freezer motor with variable DC input is investigated. The proposed circuit has two stages. Firstly, the DC output of the PV panel that varies between 150 and 300 V will be applied to the boost converter. The boost converter will boost the input voltage to a fixed 300 V DC. Next, this voltage is supplied to the single-phase full bridge inverter to obtain 230 V AC. In the end, The output of the inverter will feed a freezer motor. The PV panels can be stand-alone or grid-connected. The grid-connected PV is divided into two categories, such as with a transformer and without a transformer, a transformer type has galvanic isolation resulting in increasing the security and also provides no further DC current toward the grid, but it is expensive, heavy and bulky. The transformerless type holds high efficiency and it is cheaper, but it suffers from leakage current between PV and the grid. This paper proposes a stand-alone direct use of PV to supply a freezer, therefore, no grid connection will result in no leakage current between the PV and Grid. The proposed circuit has some features such as no filtering circuit at the output of the inverter, no battery in the system, DC-link instead of AC link that reduces no-loads, having a higher efficiency, and holding enough energy in the DC-link capacitor to get the motor started. The circuit uses no transformers, thus, it is cheaper and has a smaller size. In addition, the system does not require a complex pulse width modulation (PWM) technique, because the motor can operate with a pulsed waveform. The control strategy uses the PWM signal with the desired timing. With this type of square wave, the harmonics (5th and 7th) of the voltage are reduced. The experimental and simulation results are presented to verify the feasibility of the proposed strategy.

The energy from solar can easily harnessed to be used for various applications and grid injection. For cooking, different techniques can be utilized. Some people use the sun to cook. Other people use batteries and inverters even at noon. Hence, the cooking system becomes expensive. In fact, Photovoltaic panels did not decrease considerably in price. This paper proposes a simple electronic circuit that a Photovoltaic system can directly be used for cooking. The circuit aims at facilitating a cooking plate user to set a duty ratio. The duty ratio is limited to maintain the array voltage above a minimal level to avoid that it operates too far away from the maximal power point when less power is available. Moreover, it shows to be cost-effective compared to Photovoltaic grid connected and to charcoal. REFERENCES

This paper presents an IGBT gate driver with low parasitic capacitance between gate collector and low capacitance across the insulation. It shows the advantages of the proposed gate driver which are mainly the single supply with less parasitic capacitance and a desaturation protection. The desaturation can be easily detected at the level of the power supply. Some experimental results are presented in the paper.

Modular multilevel converter (MMC) is considered as a good technology for high-voltage direct current (HVDC) transmission systems. It can generate a good quality staircase output voltage waveform due to the cascaded connection of large number of identical sub-modules (SMs). Energy variations in SM capacitor lead to capacitor voltage fluctuations which affect the size and stability of MMC. Traditionally MMC arm voltages are controlled using direct modulation method. The closed loop and open loop compensated modulation methods are implemented to overcome the drawbacks created in direct modulation method. However, these methods rely on the accurate measurements or estimation of SM capacitor voltages. In this paper, capacitor energy variations in MMC based on direct modulation method under three different categories using proportional-resonant (PR) controllers are discussed as (a) pure sinusoidal arm current (b) sinusoidal arm current with addition of large 2nd harmonic (c) sinusoidal arm current with addition of 2nd +4th harmonics. Analytical and simulation results show reduction in capacitor energy variations in MMC while injecting harmonics in the arm currents using direct modulation method.

The photovoltaic systems sector is in full renovation continually demanding a new system that allows the user to monitor his project from long distance. One of the systems that is currently being implemented in photovoltaic farms is known as the Internet of Things. Through this system, it is intended that the user can know in the real time the status of his photovoltaic systems panels. This paper presents a new solution based on LoRaWAN technology that allows the user to have the necessary information to achieve high efficient of the photovoltaic systems panels. This system is to design and implement a new measuring circuit for measuring the output voltage and current of the PV panels from long distance by using LoRa Technology. To test the correct functioning of the device, two tests have been carried out. The first one corresponds to an essay in which the maximum distance at which a node can communicate with the gateway is measured. While the second test means measuring the voltage and current output of the photovoltaic panel of the full system. The main advantages of the final circuit can be used to monitor PV panels with low-cost, and to have high-efficiency performance from long distance.

This article proposes a new driving method for a switched reluctance motor (SRM) by using a standard full bridge. The windings in the SRM are connected in series to build a ring structure, where a controllable DC source is inserted. Based on the new structure, the theoretical analysis and calculation are made to determine the control parameters. Besides three-phase SRM, the new idea can also be applied to the SRMs with four and five phases. The new driving method is compared with the conventional method by simulation. The results show that with the new method, the ripple of torque and speed in the SRM reduces. The influence of the proposed method on the power rating and losses is then analyzed. The validation is also made to verify the application of the new method and the difference between the conventional driving method and the proposed method. The measured results match the simulated results well.

The nature of losses in ferrites has not been fully revealed yet. To achieve means for further investigation of ferrite core loss due to electric (E) field, we investigated the response of middle and side legs, cut from commercially available PQ core halves, to an applied E-field, by injecting a sine wave current in the samples. Using conventional laboratory instruments, we did impedance measurements in a wide frequency range (133 Hz–50 MHz) at temperatures that are typical for power electronics (25, 85, 100, and 120 °C). In this paper, we discuss a procedure for the extraction of intrinsic ac conductivity and dielectric constant of ferrites through an equivalent electrical circuit model based on the measured impedances. The examined material is of grade N87. The measurements show a clear influence of the investigated shapes. The results obtained start to deviate from “true” electrical properties at about 1 MHz. It appeared also that the inspected ferrites exhibit different conductivities and dielectric constants depending on the core of origin. It is obvious then that core shape, size, and production batch all have an impact on the core losses, which appear to be influenced by the E-field even at frequencies below 1 MHz.

Sophisticated techniques are required for getting accuracy in high frequency power losses of magnetic. This paper presents a high frequency power loss measurement platform (full bridge) tha...

In this paper, the delay problem of a deadbeat current control for a single-phase PWM inverter connected to the grid is investigated by applying z-transform. First, the effect of delay during one sampling period is discussed and then a predictive current observer-based controller is considered. The main objective of the control system is that the current has minimum harmonic distortion, and is in phase with the grid voltage. The control system has fast dynamic response when distortion occurs, and is robust against drift in the system parameters; it also places all the system closed-loop poles at the origin of the z-plane. Hence, it can achieve fast dynamic response with low total harmonic distortion, even under nonlinear loads. The simulation results are performed to verify the feasibility of the proposed control strategy.

Besides their magnetic properties, Mn-Zn ferrites are also characterized by appreciable electrical properties. This electro- magnetic nature of Mn-Zn ferrites material properties causes a dimensional resonance to occur in samples. The latter hinders measurements of the frequency dependences of intrinsic permittivity and electrical conductivity. In the paper, we present a sign in measurement results that shows the frequency range in which dimensional resonance has already occurred. Above this range, properties extracted from measurements are not intrinsic any longer. We refer to the sign to determine the last point of the measurement data set that is used as an input for an equivalent circuit modelling of the electrical properties. This “last point” criterion helps to exclude the possibility of modelling apparent properties instead of intrinsic ones. The results obtained show that the frequency dependent electrical properties may be well modeled even if the upper limit of the input frequency range to the curve fitting is below the frequency range in which the dimensional resonance occurs.

Large inrush currents can be harmful to equipment subjected to it and can also disturb other devices through voltage dips. Traditional ways of dealing with large inrush currents include the usage o...

This paper presents a new operating type of a three phase photovoltaic PID current control system connected to the low voltage distribution grid. This operating type introduces a 120-degree bus clamp PWM control method (120° BC-PWM). A 120° BC-PWM is a special switching sequences technique employing bus clamp sequences that use only one phase under a PWM and PID control state every 60° while the other phases are being clamped. The BC-PWM method was used to generate six PWM signals to control a three phase inverter system every 60° with constant power input and a small dc link film capacitor. The main objective of this paper is to use new PWM techniques with a PID current control method to reduce the switching losses of three phase inverters. The losses were reduced to 1/3th for each transistor by reducing the time operation for each transistor. The simulation results of the BC-PWM method show an improvement in the performance of the three phase inverter system connected to the grid. Simulation setup of the system obtained is built by using a SiC MOSFET, 5 kVA, 400 V line-line and 25 kHz switching frequency. The PID control is not continuously active for each phase but is operational in 60° and saturated at 120° in a half period. Following a proper tuning of the windup, it recovers very easily.

A simple half-bridge, galvanic separated power supply which can be short circuit proof is proposed for gate driver local supplies. The supply is made while hacking a common mode type filter as a transformer, as the transformer shows a good insulation, it has a very low parasitic capacitance between primary and secondary coils, and it is cost-effective. Very low standby losses were observed during lab experiments. This makes it compatible with energy efficient drives and solar inverters.

In this paper, the concept of active cell-balancing technique, by using a multiple-outputs double-forward converter for lithium-ion (Li-ion) batteries, is investigated. It controls two times more cells than secondaries, and it equalizes eight cells in a series. In this method, four secondaries can reasonably be wound with the same back electromotive force (EMF). This means a low pin count on the transformer and a low bill of materials (BOM). The bridge uses four N-channel MOSFETs as switches, which means two times fewer transistors than cells, resulting in fewer switching losses. This scheme is applied for controlling the minimum voltage among the cells of the lithium-ion battery. It uses a multi-winding transformer based on a forward double converter structure. Conventional schemes using a multi-winding transformer for electric vehicles (EVs) require an equal number of secondaries per cell. This scheme requires one secondary for two adjacent cells, thus the number of secondaries is reduced by a factor of two. Also, the redistribution of charge from a high cell to a low cell does not require many switching components and little intelligence to determine low cell voltage detection. The basic principle of this method is to use the overall battery pack voltage as a reference to supply individual cells, using a forward converter containing a transformer with a well-chosen winding ratio. The experimental and simulation results are performed to verify the feasibility of the proposed system.

In this paper, the concept of a forward balancing technique fed by a buck converter for lithium-based batteries in Electrical Vehicle (EV) applications is investigated. The proposed active topology equalizes eight cells in a series in a battery pack, by using a forward converter for each battery pack and the whole battery packs, using a buck converter. The battery bank consists of four battery packs, which are in series. Therefore, the proposed system will equalize 32 cells in series. In this paper, the proposed circuit employs a single transistor used in a Zero Voltage Switch (ZVS) for the forward converter. In practice, this means a capacitor in parallel with the switch at the same time a demagnetizing of the transformer is obtained. The circuit realizes a low Electromagnetic Interference (EMI) and reduces ringing. To overcome the problem of many pins on a coil former, the transformer secondary windings are made by using hairpin winding, on a ring core. It permits, e.g., having eight secondaries and uniform output voltages. Each secondary winding is made by two hairpin turns using two zero-Ohm resistors in series. The proposed topology has less components and circuitry, and it can equalize multiple battery packs by using a single buck converter and several forward converters for each battery pack. Experimental and simulation results are performed to verify the viability of the proposed topology.

Modular multilevel converters (MMCs) are quickly emerging as a suitable technology for a voltage-source converter-based high-voltage direct-current (VSC-HVDC) transmission systems due to its numerous advantages as reported in literature. However, for a large DC-network, MMCs require large numbers of sub-modules (SMs) and switches, which makes its modeling very challenging and computationally complex using electromagnetic transient (EMT) programs. Average Value Model (AVM) provides a relatively better solution to model MMCs by combining cells as an arm equivalent circuit. Circulating current is an important issue related to the performance and stability of MMCs. Due to circulating currents, power loss in a converter increases as root mean square (RMS) values of the arm current increases. The traditional method for inserting SMs in each arm is based on direct modulation, which does not compensate for the arm voltage oscillations, and generates circulating current in each leg of a three-phase MMC. This paper presents a new method for reducing the circulating current by adding 2nd and 4thharmonics in the upper and lower arm currents of an MMC. Less capacitor energy variations reobtained by the proposed method compared to traditional direct modulation methods. The proposed method is tested on a common symmetrical monopole (point-to-point) MMC-HVDC system using vector current control strategy in PSCAD/EMTDC software. Analytical and simulation results show the effectiveness of the new method in minimizing the circulating current and arm voltage oscillation reductions as compared to the direct modulation approach.

This article developed a coupled inductor balancing method to overcome cell voltage variation among cells in series, for Lithium Ion (Li-ion) batteries in Electrical Vehicles (EV). For an "eight cells in series" example, the developed balance circuit has four inductors, one magnetic circuit with one winding per two cells, and one control switch per cell, as compared to the traditional inductor-based equalizer that needs N-1 inductors and magnetic circuits for N number of cells and more switches. Therefore, ultimately, a more efficient, cost-effective circuit and low bill of materials (BOM) will be built up. All switches are logic-level N-Channel metal-oxide-semiconductor field-effect transistors (MOSFETs) and they are controlled by a pair of complementary signals in a synchronous trigger pattern. In the proposed topology, less components and fast equalization are achieved compared to the conventional battery management system (BMS) technique for electrical vehicles based on the inductor balancing method. This scheme is suitable for fast equalization due to the inductor-based balancing method. The inductors are made with a well-chosen winding ratio and all are coupled with one magnetic core with an air gap. Theoretical derivation of the proposed circuit was well-presented, and numerical simulation relevant to the electrochemical storage devices was conducted to show the validity of the proposed balance circuit. A complete balance circuit was built to verify that the proposed circuit could resolve imbalance problems which existed inside battery modules.

In this paper, a new smart monitor and control system has been designed for injected power application to grid from a three-phase photovoltaic inverter (a smart monitor and control system (SMCS)). The system consists two main units. Firstly, the control system unit: this unit connects directly to the inverter to measure the output voltage of three-phase photovoltaic inverter and the control circuit, It can turn the inverter ‘on’ or ‘off’ from a long distance. Secondly, the monitoring unit: this unit is designed to monitor the states of the photovoltaic inverter system from long distances. It has two monitoring options OLED and a smartphone monitoring application. LoRa technique (long range) used to send and receive data between controllers system and monitoring system. LoRa is a new type of wireless communication technology within the Internet of Things (IoT). The SMCS application has been designed by using open source software “MIT App Inventor 2”; this application is used to sends and receives the data from a control unit by using Bluetooth as a wireless communication in order to monitor and control the whole system. The main advantage of the SMCS that it can monitor and control three-phase photovoltaic inverters that have been installed in remote and rural areas.

Photovoltaics is the core of the greatest current system that using solar energy and it is regarded as the basic of sustainable engineering techniques. It is the method of exchanging daylight straightly to electricity power. The LoRa communication technology is a far-range, economic-power, small rate of bit technology. It is sponsored as a basic settling for the Internet of Things (IOT). This technology is applied where equipment is battery-feed with narrow bandwidth was required. In this manuscript, a novel method that depends on the LoRa technology is considered to observes and governs the power generated from a three-phase Photovoltaics inverter scheme that fed to grid directly. This scheme is designed with dual parts. The first one is for evaluating and control invertor part. This part attaches straight through the inverter to recognize the working of the inverter by changing the state of inverter from far spaces. The second part which is uses the liquid crystal display and a smart-phone observing application. The phone program is prepared using MIT App Inventor to observe and govern the entire scheme. The results show that this system is robust against the circumstances around the system and gives accurate results with minimum error when using in urban lands. The benefit of this system is to monitor and control the photovoltaic system located in remote place without need of attend to generating place.

A battery management system (BMS) plays an important role in electric vehicles (EVs) in order to achieve a reasonable-lasting lifetime. An equalizing method is essential in order to obtain the best performance. A monitoring system is required to check if any cell voltage is high or low. In this paper, an equalizing and monitoring system for an ultra-light electric vehicle is proposed. The monitoring system detects if one cell is fully charged or all cells are fully charged and the equalizing system tops each cell at the desired voltage. To solve this issue, a light-emitting diode (LED) band gap is used as a voltage reference to inform the user if any cell is at its high voltage. A smart monitoring displays on the liquid crystal display (LCD), if one cell is high or all cells are high. This detection also provides a signal to the microcontroller to turn on/off the charger if all cells are high. Also, a Bluetooth module was designed to command the microcontroller the charger to turn on/off via voice/text message by using a smartphone. Additionally, a new smart monitoring system based on the Bluetooth model (HC05) and mobile app has been made in order to monitor individual cell voltage. A major feature of the system is to draw a very-low current, so that the system does not contribute significantly to the self-discharge of the battery and the circuit does not need sophisticated control. Manufacturers of large electric vehicles may have more intelligent systems that may require a permanent connection to the grid and allow high standby losses, where more state of charge (SOC) may be lost per day. The paper is rather focused on reducing the standby losses, and to activate the equalizer only when charging and/or driving. The experimental results are performed in order to verify the feasibility of the proposed circuit.

The use of renewable energy such as wind power is one of the most affordable solutions to meet the basic demand for electricity because it is the cleanest and most efficient resource. In Algeria, the highland region has considerable wind potential. However, the electrical power system located is this region is generally not powerful enough to solve the problems of voltage instability during grid fault conditions. These problems can make the connection with the eventual installation of a wind farm very difficult and inefficient. Therefore, a wind farm project in this region may require dynamic compensation devices, such as a distributed-flexible AC transmission system (D-FACTS) to improve its fault ride through (FRT) capability. This paper investigates the implementation of shunt D-FACTS, under grid fault conditions, considering the grid requirements over FRT performance and the voltage stability issue for a wind farm connected to the distribution network in the Algerian highland region. Two types of D-FACTSs considered in this paper are the distribution static VAr compensator (D-SVC) and the distribution static synchronous compensator (D-STATCOM). Some simulation results show a comparative study between the D-SVC and D-STATCOM devices connected at the point of common coupling (PCC) to support a wind farm based on a doubly fed induction generator (DFIG) under grid fault conditions. Finally, an appropriate solution to this problem is presented by sizing and giving the suitable choice of D-FACTS, while offering a feasibility study of this wind farm project by economic analysis.

This paper proposes a new driving method for switched reluctance motors (SRMs) using the standard full-bridge inverter. In spite of changing the internal structure of an SRM, the proposed method uses an extra ring structure circuit to make it possible for the inverter to drive the SRM. Next to the standard converter, a controllable DC source is needed. With theoretical analysis and calculation, the reference value of the circulating current in the ring structure was determined and the new method was proven via simulation. A comparison was made with the conventional method for driving an SRM: the asymmetric H-bridges. Also, the current studies were then made to confirm that the SRM could be controlled without lowering the performance of the machine. Experimental verification was also made under different conditions, as well as comparison with the simulation results.

The concept of active cell equalizing method based on multi-winding transformer balancing for Lithium Ion (Li-ion) batteries is presented in this paper. In a battery pack, voltage differences exist between cells due to charging and discharging process thus, a battery management system (BMS) is required to ensure that all battery cells are equally charged or discharged. An equalizing method is essential to achieve the best performance. A number of cell balancing method have been presented. Among them multi-winding transformer balancing method has fast equalization time, and is easy to control. As compared to the conventional multi-winding transformer (Fly back structure) that uses diodes and requires air gap, this method (Forward) uses MOSFETs as a switch in the output and uses single phase inverter in the input. Fast equalization, easy to control, high efficiency and easy isolation are some of its features. The simulation results are accomplished to demonstrate the viability of the system.

This paper presents the concept of charging of Lithium Iron Phosphate (LFP) battery cells in an Electric vehicle (EV). Charger topologies play an important role in EVs to increase the performance of the batteries. The batteries should be charged and discharged to achieve the best performance and long lifetime. In this paper, the design of a charger with four battery packs, that consist of eight cells in a series is investigated. Two battery chargers are performed in order to feed the whole battery packs. A current driver is proposed to limit the current from the charger and the operational principle is based on a MOSFET constant current driver. The battery should only be connected when the car needs to drive in order to avoid unnecessary losses. Also a resistor is needed to avoid high starting currents, thus the startup system is required and designed to overcome this problem. The operational principle of the proposed circuit is explained in details and the experimental result are performed to verify the feasibility of the proposed system.