converter

Open Access Article

1 - A design of Rectangular Waveguide TM11 to TE10 Mode Converter for S-band Applications
Hamed noroozy Hossein Chabok Samane Pakniyat

A design of a compact, easy to fabricate and applicable structure rectangular waveguide TM11 to TE10 mode converter is presented in this paper. The design procedure of the proposed structure can be divided into two parts in sequence. The beginning one is dedicated to th More

A design of a compact, easy to fabricate and applicable structure rectangular waveguide TM11 to TE10 mode converter is presented in this paper. The design procedure of the proposed structure can be divided into two parts in sequence. The beginning one is dedicated to the transformation from TM11 to TEM mode using a central conductor, while the second part is the transformation from TEM to TE10 mode using a dielectric loaded waveguide carrying out 180o phase shift. The proposed structure has the advantage of high efficiency of above 90 %, which are demonstrated in simulation results Manuscript profile

Open Access Article

2 - A New Calibration Method for SAR Analog-to-Digital Converters Based on All Digital Dithering
Ebrahim Farshidi Shabnam Rahbar

10.7508/jist.2017.17.001

In this paper a new digital background calibration method for successive approximation register analog to digital converters is presented. For developing, a perturbation signal is added and also digital offset is injected. One of the main advantages of this work is that More

In this paper a new digital background calibration method for successive approximation register analog to digital converters is presented. For developing, a perturbation signal is added and also digital offset is injected. One of the main advantages of this work is that it is completely digitally and eliminates the nonlinear errors between analog capacitor and array capacitors due to converter’s capacitors mismatch error by correcting the relative weights. Performing of this digital dithering method does not require extra capacitors or double independent converters and it will eliminate mismatches caused by these added elements. Also, No extra calibration overhead for complicated mathematical calculation is needed. It unlike split calibration, does not need two independent converters for production of two specified paths and it just have one capacitor array which makes it possible with simple architecture. Furthermore, to improve DNL and INL and correct the missing code error, sub radix-2 is used in the converter structure. Proposed calibration method is implemented by a 10 bit, 1.87-radix SAR converter. Simulation results with MATLAB software show great improvement in static and dynamic characteristics in applied analog to digital converter after calibration. So, it can be used in calibration of successive approximation register analog to digital converters. Manuscript profile

Open Access Article

3 - Design of UPFC Controller Using Bilinear Equation for Improving Power System Stability
M. Nayeripour A. Yazdian Varjani M. Mohamadian

In this paper the model of UPFC is represented by a bilinear equation. Then with the second method of Lyapunov, the input of converter is derived such that the derivative of energy function is negative. The design of controller is carried out with two methods. In the fi More

In this paper the model of UPFC is represented by a bilinear equation. Then with the second method of Lyapunov, the input of converter is derived such that the derivative of energy function is negative. The design of controller is carried out with two methods. In the first method, the controller is linearized at operating point. In the second method, the nonlinear method is used in the series converter and the PI controller is used in the shunt converter. Reduction of first swing peak after fault clearing is the main advantage of designed controller with respect of PI controller. Manuscript profile

Open Access Article

4 - A Control approach with Controllable Response Time for Power Control of the Power Electronic Based Distributed Generation Resources in Microgrids
E. Zare Abandankeshi مجید شهابی

Most wind turbines, photovoltaic and fuel cells need a DC/AC converter as an interface for connection to the main grid. Power electronics based distributed generation resource has two parts: power circuit and control circuit of converter. In this paper, a new method whi More

Most wind turbines, photovoltaic and fuel cells need a DC/AC converter as an interface for connection to the main grid. Power electronics based distributed generation resource has two parts: power circuit and control circuit of converter. In this paper, a new method which is based on current control by using internal model control method is presented, in order to control active and reactive power of power electronics interfaced distributed generation resource. The main benefit of using internal model control method is that it can reduce number of required parameters for PI controller tuning to one parameter which is desired closed-loop band width (). It should be mentioned that parameter  can be computed regarding response rise time. Therefore, values of KI and KP can be determined with the selection of desired band width. So, the system can be designed just with the selection of one parameter (rise time tr). The proposed control method can be used in micro-grids containing power electronic interfaced DGs, in both modes of operation (connected to grid and islanded micro-grid). Manuscript profile

Open Access Article

5 - Unity Power Factor MPPT for PMSG Wind Turbines Equipped with Matrix Converter
A. Nateghi H. Kazemi Karegar

In this paper, a new control method is proposed for extracting the maximum power of wind turbines equipped with Permanent Magnet Synchronous Generator (PMSG), which is connected to the grid via a matrix converter. The method calculates the optimal rotation speed of wind More

In this paper, a new control method is proposed for extracting the maximum power of wind turbines equipped with Permanent Magnet Synchronous Generator (PMSG), which is connected to the grid via a matrix converter. The method calculates the optimal rotation speed of wind turbine and finds the optimal operation point by hill climbing method. The proposed method is simple and it does not need to use some complex methods such as field oriented and rotor position estimation. Wind turbine speed, electrical torque and consequently maximum output power of wind turbine are obtained by the perfect control of output phases and amplitudes of matrix converter. Moreover, the maximum power is injected to the grid under unity power factor. The proposed method is simulated in MATLAB programming software and the obtained results approve the validity of the method. Manuscript profile

Open Access Article

6 - Design of a High-Voltage Unity Power Factor Charger Based on Bi-directional Boost Converter with Electromagnetic Compatibility Filter
A. Skandarnezhad S. A. Abrishamifar

High voltage chargers are being used in the equipments such as electrical vehicles, uninterruptible power supplies and aircrafts. The converter introduced here is based on bi-directional boost topology. The output voltage of batteries set is larger than the input source More

High voltage chargers are being used in the equipments such as electrical vehicles, uninterruptible power supplies and aircrafts. The converter introduced here is based on bi-directional boost topology. The output voltage of batteries set is larger than the input source voltage amplitude, and this converter can transfer the energy both from the source to the batteries bank and vice versa. Input source voltage is sine wave and the output voltage is DC. Both conversion of AC-to-DC and DC-to-DC is performed in one stage and the control scheme of switches is based on hysteric control method to achieve the unity power factor. One can use the electrical equations presented here to define the converter and EMC filter elements value. Finally, simulation results performed on a typical converter show the control method authenticity and effectiveness of the analyses presented here. Also some suggestion for the future works is proposed. Manuscript profile

Open Access Article

7 - A New Non-Isolated SEPIC Converter with High Gain and High Efficiency for Photovoltaic Application
M. Mahmoudi B. Mirzaeian Dehkordi M. Niroomand

In this paper, a new non-isolated SEPIC converter for photovoltaic application is introduced and analyzed. Regarding to low output voltage PV panel and high voltage application of PV systems, a high gain converter is designed. This converter has advantages such as high More

In this paper, a new non-isolated SEPIC converter for photovoltaic application is introduced and analyzed. Regarding to low output voltage PV panel and high voltage application of PV systems, a high gain converter is designed. This converter has advantages such as high output voltage gain while keeping the switch voltage stress equal to a regular SEPIC converter, improve the turn-on and turn-off transients of the switch and high efficiency. Also, switching losses and EMI noise are reduced by soft switching method. The MOSFET operates at zero-voltage-switching (ZVS) turn-off and near zero-current-switching (ZCS) turn-on. Manuscript profile

Open Access Article

8 - A New Pulse Frequency Waveform Synthesizing Method Using IPT Frequency-Gain Characteristics
M. H. Ameri A. Yazdian Varjani M. Mohamadian

The electrical connection between the load and source can be eliminated using inductive power transfer. Supplying AC Loads, such as V2G and single phase motors, is one of the many applications of IPT. To supply an AC load, the rectified output power of IPT should be del More

The electrical connection between the load and source can be eliminated using inductive power transfer. Supplying AC Loads, such as V2G and single phase motors, is one of the many applications of IPT. To supply an AC load, the rectified output power of IPT should be delivered to an inverter. The sequential dc/ac/dc/ac conversions cause IPT efficiency decreases. To make an output AC voltage with acceptable THD, the carrier frequency of the PWM method should be several times the reference frequency which increases the switching loss. In this paper based on IPT gain-frequency characteristics, a new pulse frequency waveform synthesizing method (PFWS) has been presented. This method eliminates secondary inverter switching losses. It is shown that besides loss reduction, synthesized sinusoidal waveform at secondary of IPT, causes the Total Switching Device Power (TSDP) of secondary converters decrease, therefore their lifetime increase. Simulated and experimental results of the developed laboratory model which verify and illustrate the operation of the proposed method are presented. Manuscript profile

Open Access Article

9 - Designing an Applicable MIMO DC-DC Converter with Multivariable Controller for SMES System
M. R. Alizadeh Pahlavani S. Taghipour Broujeni

In modern power systems, utilization of renewable energy sources makes some difficulties for the power grid. One of these problems is shortage of electrical power during conditions which renewable energy sources cannot generate electrical power. For example, during shad More

In modern power systems, utilization of renewable energy sources makes some difficulties for the power grid. One of these problems is shortage of electrical power during conditions which renewable energy sources cannot generate electrical power. For example, during shading conditions, the output power of the PV array is negligible. Using SMES (Superconducting Magnetic Energy Storage) systems is one of the applicable solutions which has been proposed to solve mentioned problem. In SMES system, energy is stored at high power inductances and during critical conditions; this power can be delivered to the load. One of the important parts of SMES systems is Multi input - Multi Output (MIMO) DC-DC converter. In this paper, at first step, one topology has been designed for the MIMO DC-DC converter. This topology has remarkable advantages such as fewer electrical elements and better controllability than other topologies. In the second part of this paper, based on multivariable controller strategy, an efficient controller has been designed for the SMES system which can set the output voltages of DC-DC converter at predetermined values. The most important feature of proposed controller is its efficiency at different conditions which some of these conditions make serious problems for conventional controllers. Generally, the objective of this paper is designing one SMES systems with an appropriate controller, which can regulate the output voltages at different conditions. Manuscript profile

Open Access Article

10 - Design and Implementation of a New Adaptive Sliding Mode for Current Control in Islanding Mode Operation
M. M. Ghanbarian M. Nayeripour A. H. Rajaei

This paper proposes a new modified adaptive sliding mode controller in order to control the inverters of DGS in the voltage and current (power) control modes in a microgrid. An observer is used to estimate the uncertain parameters in controller design and considering t More

This paper proposes a new modified adaptive sliding mode controller in order to control the inverters of DGS in the voltage and current (power) control modes in a microgrid. An observer is used to estimate the uncertain parameters in controller design and considering these estimated values, the controller is adapted to new condition. In the power management strategy, one of inverter controls the voltage and the other inverter controls the load current and balances the active power. Due to delays in startup power electronic converter and sliding mode controller, the result of controller implementation with classical controllers does not meet the requirement and so, considering these delays with adaptive controller, the performance will be improved considerably and the reference signal will be tracked with lower steady state error in comparison with classical sliding mode controller. Moreover, this controller reduces the total harmonic distortion and improves the rms and peak value tracking. Implementation of system using DSP/TMS320F28335 as well as MATLAB simulation validates the performance of system in different conditions. Manuscript profile

Open Access Article

11 - A Reduced Switch Count Three-Phase AC/AC Converter with Six IGBTs
M. Heydari A. Yazdian Varjani

Reducing the number of semiconductor switches in power electronic converters has been a continuing effort in recent years as a measure to enhance the system reliability and to decrease its size, weight, and component cost. For these reasons, a new reduced switch count t More

Reducing the number of semiconductor switches in power electronic converters has been a continuing effort in recent years as a measure to enhance the system reliability and to decrease its size, weight, and component cost. For these reasons, a new reduced switch count three-phase ac/ac converter is being proposed. Being realized by only six active switches and anti-parallel diodes, the proposed converter topology employs the minimum number of semiconductor devices amongst the converters of its kind. It also features unity power factor, regenerative operation, pulse width modulated output voltage, and sinusoidal input current. The reduced number of switches results in a simplified associated gate drive circuit as well as cooling system which, in turn, may cut the overall manufacture cost, especially in low voltage and low power applications. The modulation scheme of the new converter is developed, and a control algorithm is proposed for the converter’s rectifier side. Moreover, an analysis is performed on the dc link capacitor sizing for the purposes of reducing dc link voltage ripple, balancing the input current, and lowering its THD. The simulation and experimental results corroborate the transient and steady state performance of the proposed converter topology. Manuscript profile

Open Access Article

12 - Speed Control of Matrix Converter-Fed Five-Phase Permanent Magnet Synchronous Motors under Unbalanced Voltages
B. Yousefi S. Soleymani B. Mozafari S. A. Gholamian

Five-phase permanent magnet synchronous motors (PMSM) are often used for specific applications, in which the precise speed control of the motor by an appropriate driver design is important. The use of three-phase to five-phase matrix converter is a suitable technique fo More

Five-phase permanent magnet synchronous motors (PMSM) are often used for specific applications, in which the precise speed control of the motor by an appropriate driver design is important. The use of three-phase to five-phase matrix converter is a suitable technique for constructing such a motor driver. Since the input voltages of such converters are directly supplied by input three-phase supply voltages, an imbalance in the voltages will cause problems such as unbalanced stator currents and electromagnetic torque fluctuations, making it inefficient to use such converters. In this paper, a new method is proposed to remove torque oscillator factors based on direct power control (DPC). In this way, a number of features including speed, torque, and flux of the motor will improve in terms of the above-mentioned conditions. Simulations are analyzed using Matlab/Simulink software. Manuscript profile

Open Access Article

13 - Operational Analysis of the Buck Boost DC–DC Converter with High Step-Up Voltage Gain
M. R. Banaei H. A. Faeghi Bonab

In some applications that we need a high voltage gain such as the photovoltaic cell and fuel cell, high step up dc-dc converters must be used, but conventional boost converter cannot provide the high voltage gain. For this reason, in this paper, a single switch transfor More

In some applications that we need a high voltage gain such as the photovoltaic cell and fuel cell, high step up dc-dc converters must be used, but conventional boost converter cannot provide the high voltage gain. For this reason, in this paper, a single switch transformerless high step-up buck boost dc-dc converter with reduced voltage stress on the semiconductors is proposed. The proposed converter has higher voltage gain in step-up mode in comparison with conventional boost and buck-boost converters. Reduced voltage stress on the active switch allows to choose lower voltage rating MOSFETs to reduce both switching and conduction losses. Low voltage stress on the diodes allows the use of Schottky rectifiers for alleviating the reverse-recovery current. The proposed converter can be operated in the continuous conduction mode (CCM) and the discontinuous conduction mode (DCM). In this paper, different operation modes of the proposed converter, calculation of the voltage gain, the currents that flow through the components, efficiency and capacitors voltage ripple are presented. To verify the operation of the proposed converter, simulation results via PSCAD software and experimental results are provided. Manuscript profile

Open Access Article

14 - A Generalized Relationship for Calculation of Critical Inductance in an n-Input Buck DC-DC Converter
K. Varesi S. H. Hosseini M. Sabahi E. Babaei

critical inductance is one of the factors that decides continuous, boundary or discontinuous conduction mode of dc-dc converters. In applications like mining, the Continuous Conduction Mode (CCM) and consequently safety of converter can be guaranteed by proper selection More

critical inductance is one of the factors that decides continuous, boundary or discontinuous conduction mode of dc-dc converters. In applications like mining, the Continuous Conduction Mode (CCM) and consequently safety of converter can be guaranteed by proper selection of inductance. So, calculation of critical inductance and proper sizing of inductor is an important issue in designing of dc-dc converters. In this paper, a non-isolated n-input buck dc-dc converter is introduced. Then, the operational modes and energy transfer process is investigated and discussed in detail. The critical inductance is calculated for 3 and 4-input versions. Using the inductive reasoning, a generalized relationship is proposed for calculation of critical inductance of converter with any number of inputs (n-input version). The proposed generalized relationship not only reduces the amount and time of calculation in design stage, but also presents a better view of performance of converter. The 3 and 5-input version of converter has been modeled and simulated in PSCAD/EMTDC software. Also, the 3-input version of converter has been practically implemented. The obtained simulation and experimental results confirm the validity of proposed generalized relationship for critical inductance calculation of n-input buck dc-dc converter. Manuscript profile

Open Access Article

15 - Predictive Control of Modular Multilevel Converters Using Sphere Decoding Algorithm
H. Shafaiyeh Hiag R. Mahboobi Esfanjani Mohammad Hejri

Modular Multilevel Converters, by increasing the number of voltage levels the quality of output waveform is improved and the semiconductor switches tolerate low voltage values. However, design of switching strategy in these complicated circuits is challenging. In this p More

Modular Multilevel Converters, by increasing the number of voltage levels the quality of output waveform is improved and the semiconductor switches tolerate low voltage values. However, design of switching strategy in these complicated circuits is challenging. In this paper, based on sphere decoding algorithm, a predictive controller with finite control set is proposed to regulate load current while minimizing both capacitor voltage variations and circulating currents. The suggested scheme decreases the computational burden of optimization stage which is considerable for long prediction horizons and modular converters with high number of voltage levels. The suggested scheme is simulated for a practical modular multilevel converter to demonstrate its performance compared to some rival methods. Manuscript profile

Open Access Article

16 - LMI Robust Control Design for SIDO Boost Converter Based on SFG Modelling Method
M. Abbasi Mohammad Reza Alizadeh Pahlavani Ahmad Afifi

A robust control design process based on a linear Matrix Inequalities (LMI) for a Single Inductor Multi Output (SIMO) boost converter has been presented in this paper. Considering complicated multi-stages operation of SIDO converter, Signal Flow Graph (SFG) modelling wa More

A robust control design process based on a linear Matrix Inequalities (LMI) for a Single Inductor Multi Output (SIMO) boost converter has been presented in this paper. Considering complicated multi-stages operation of SIDO converter, Signal Flow Graph (SFG) modelling was used to predict all behavior of the converter. Using the SFG model, nonlinearities and uncertainties was modelled as a convex polytope for LMI design constraints. This method guarantees a certain perturbation rejection level and a region of pole location. The derived parameters from LMI were applied on state-feedback coefficients in Matlab/Simulink to show the validity of the presented LMI method. Finally, the obtained results have been compared with a conventional PI controller. Manuscript profile

Open Access Article

17 - A DC-DC Interleaved Converter Based on Buck Topology with High Step-Down Conversion Ratio
M. Ghanbari M. R. Yazdani

High step-down conversion ratio cannot be achieved by the conventional buck converter. Also, the switch voltage stress is another drawback of the regular buck converter for high input voltages. In this paper, a DC-DC switching converter using interleaved method is propo More

High step-down conversion ratio cannot be achieved by the conventional buck converter. Also, the switch voltage stress is another drawback of the regular buck converter for high input voltages. In this paper, a DC-DC switching converter using interleaved method is proposed based on the buck topology to achieve a high step-down conversion ratio. In the structure of this converter, a coupled inductor is used without need of another auxiliary winding. After presenting key waveforms and analysis of the proposed converter, the conversion ratio curves are offered. Moreover, simulation waveforms of a 240 W converter prototype with the input voltage of 150 V and the output voltage of 24 V are shown to verify the theoretical analysis. Manuscript profile

Open Access Article

18 - A New Multiport DC-DC Converter Based on T-Source for PV-Battery Applications
saber zare A. Rajaei M. R. Kheyrati Mohammad Mardaneh

A new structure of multi-port DC-DC converter is proposed which is based on T-Source converter. It can be used for hybrid renewable energy applications. Two input ports includes a solar panel and battery. The main advantages of the converter are including; high voltag More

A new structure of multi-port DC-DC converter is proposed which is based on T-Source converter. It can be used for hybrid renewable energy applications. Two input ports includes a solar panel and battery. The main advantages of the converter are including; high voltage gain, continuous input current, independent mode operation of input ports, and high efficiency. Different switching modes are discussed in the relations for steady state operation of the converter are derived. A prototype of the converter is provided and several tests are performed which validates the simulations and theoretical predictions of the converter. Manuscript profile

Open Access Article

19 - Global Hybrid Modeling and Control of a DC-DC Buck-Boost Converter via Mixed Logical Dynamical Systems
Mohammad Hejri

This paper presents a new model for a DC-DC buck-boost converter considering its all controlled and uncontrolled switching phenomena in both continuous and discontinuous conduction modes. The proposed model is developed based on hybrid systems theory using mixed-logical More

This paper presents a new model for a DC-DC buck-boost converter considering its all controlled and uncontrolled switching phenomena in both continuous and discontinuous conduction modes. The proposed model is developed based on hybrid systems theory using mixed-logical dynamical (MLD) systems, and an improved version of these systems called as extended mixed-logical dynamical (EMLD) Systems. Compared to the existing MLD and EMLD models of the DC-DC converters, the proposed model contains fewer numbers of integer variables and inequalities, and, as a result, leads to the less complexity and solution time of the mixed integer optimization problems arising from the corresponding hybrid model predictive controllers. The advantage of the proposed modeling and control method is evaluated via the comparison of the existing MLD models and hybrid predictive controllers as well as classic proportional-integral (PI) controllers. Moreover, the theoretical challenges for the closed-loop stability proof are discussed and in this regard some future research outlines and ideas are introduced. The steady state and transient performance of the closed-loop control system over a wide range of the operation points show the satisfactory operation of the proposed modeling and control scheme for the DC-DC buck-boost converter. Manuscript profile

Open Access Article

20 - Investigation and Analysis of a Soft Switching Multi-Input Converter for Renewable Energy Sources
B. Mazaheri Tehrani M. Khorram Dashti B. Raeisi احسان اديب

Renewable energy sources cannot provide load power continuously which is an important challenge in applying these sources. Therefore, usually several renewable sources; such as, solar cells and fuel cells are applied simultaneously. A converter can be applied for each s More

Renewable energy sources cannot provide load power continuously which is an important challenge in applying these sources. Therefore, usually several renewable sources; such as, solar cells and fuel cells are applied simultaneously. A converter can be applied for each source which results in high implementation cost. Therefore, multi input converters are used to reduce cost and volume of the system. In this paper, a new soft switching multi input converter is proposed. In this converter by applying one additional switch, soft switching is achieved for all main switches. The proposed converter is analyzed and design considerations are discussed. Manuscript profile

Open Access Article

21 - Balancing the DC Bus Voltage of a Cascaded H-Bridge Converter with Adaptive Carrier Phase Shift Method
M. Rahali Asl M. Saradarzadeh A. R. Namadmalan

The cascaded H-bridge converter is one of the useful multilevel converters for high power applications. The unbalancing of cells DC bus voltages is a major issue in this topology especially when the capacitors are charged from the grid, which mainly is caused by the dif More

The cascaded H-bridge converter is one of the useful multilevel converters for high power applications. The unbalancing of cells DC bus voltages is a major issue in this topology especially when the capacitors are charged from the grid, which mainly is caused by the different losses of cells. In this paper a new method is proposed for balancing the cells DC bus voltages without need to measure the cells current. This method is named as “adaptive carrier phase shift”, which is based on the phase shift pulse width modulation. The balancing between the cells DC bus voltages is achieved by measuring the voltages and changing the carrier phase shift. This method is analyzed mathematically and is used to balance a 7-level cascaded H-bridge STATCOM. The feasibility and appropriate function of balancing method is investigated by the simulation studies in the MATLAB/Simulink software. Manuscript profile

Open Access Article

22 - Analysis and Design of a Low Power Analog to Digital Converter Using Carbon Nano-Tube Field Effect Transistors
Saeedeh Heidari D. Dideban

Nowadays, analog to digital (A/D) converters are indistinguishable parts of system on chip (soC) structures because they omit the distance between analog real data and digital logic world. Due to this fact and ever increasing trend for using portable instruments, the fi More

Nowadays, analog to digital (A/D) converters are indistinguishable parts of system on chip (soC) structures because they omit the distance between analog real data and digital logic world. Due to this fact and ever increasing trend for using portable instruments, the figures of merit for design of these converters such as speed, power and occupied area are improved. Different methods are proposed to improve the performance of these converters. In this paper, we design a fast and low power ADC using carbon nano-tube field effect transistor (CNTFET) and then its performance is comprehensively compared with a MOSFET based counterpart at the same technology node. The performance is studied two encoders: ROM and Fat tree. The obtained results are presented using HSPICE simulator at 0.9 V power supply. The simulated data from CNTFET based converter shows significant improvements in delay and power compared with its CMOS based counterpart. The power and delay obtained from CNTFET based converter using ROM encoder are improved by 92.5% and 54% with respect to the same parameters obtained from CMOS based design while the improvements using a Fat tree encoder in CNTFET converter reaches 93% and 72% in comparison with CMOS conventional design. Manuscript profile

Open Access Article

23 - Design of a Fully Integrated Low Voltage, High Efficiency Capacitive, DC-DC Converter for Energy Harvesting Applications
A. Hassanzadeh F. Alirezaei

In this paper, a low voltage boost DC-DC converter has been presented. The circuit can be used for increasing the output voltage of miniature low voltage generators such as TEG, solar and piezoelectric. The converter is fully integrated and works with low voltages as lo More

In this paper, a low voltage boost DC-DC converter has been presented. The circuit can be used for increasing the output voltage of miniature low voltage generators such as TEG, solar and piezoelectric. The converter is fully integrated and works with low voltages as low as 200 mV, and the output voltage can reach 1 V. Body biasing has been used to handle low input voltages. The output power density is 50 µW/mm2, and the converter uses 5 cross coupled stages with 76% efficiency. The maximum total efficiency of the converter for 6 µA load is 52%. The converter uses 0.2 mm2 of chip area using 90 nm technology. Manuscript profile

Open Access Article

24 - Reduction of Magnetic Core Losses in Forward Converter for Driving Magnetron Lamp
Mohamad Reza Banaei ابوالفضل نصیری

In this study, a forward converter with phased shifted active clamp is presented for the driving of magnetron lamp (4 kV, 300 mA, 1000 ±40 W).The presented converter is of a boost and high-gain type. To reduce the voltage stress, the active clamp structure is used. In a More

In this study, a forward converter with phased shifted active clamp is presented for the driving of magnetron lamp (4 kV, 300 mA, 1000 ±40 W).The presented converter is of a boost and high-gain type. To reduce the voltage stress, the active clamp structure is used. In addition, using the clamp switch phase shifted method, while the maximum flux density of the transformer core retains power, it is possible to increase the time the main key is turned on. Thus, with the same nucleus, the possibility of increasing power transmission is created. Therefore, in the same power, the volume, weight and price of the core used should be reduced.Also, a series resonance circuit provides soft switching conditions. Maximum and average power supply power is controlled for minimum losses. The power supply delivers about 1 kW with an average power of about 250 W by adjusting the time the converter is enabled. Other advantages of the proposed circuit include simply power circuit, reduction of the number of switching elements and reduction of switching losses. The design results have been simulated and verified by PSCAD software. Manuscript profile

Open Access Article

25 - Controller Design and Asymptotic Stability Analysis of a Buck Converter with a Cascade Control Structure Using Singular Perturbation Theory
Sajad Azarastemal Mohammad Hejri

This paper presents the theoretical proof for the closed-loop asymptotic stability of a DC-DC buck converter based on singular perturbation theory. Due to the two-time scales structure of this converter with fast and slow dynamics, a cascade control structure is used to More

This paper presents the theoretical proof for the closed-loop asymptotic stability of a DC-DC buck converter based on singular perturbation theory. Due to the two-time scales structure of this converter with fast and slow dynamics, a cascade control structure is used to control it. This controller has two control loops: an outer loop to control the output voltage based on the proportional-integral control and an inner loop to control the inductor current based on the sliding mode control. The controllers in the loops are designed based on perturbation theory to meet the constraints of the converter and ensure the asymptotic stability of the closed-loop system over a wide range of initial conditions. For validation, the proposed control design method is simulated for a typical buck converter in the MATLAB-SIMULINK environment. The simulation results show that by properly selecting the PI controller coefficients in the outer loop, the problem requirements are met, and the asymptotic stability of the closed-loop system is guaranteed in a wide range of the converter initial conditions. Furthermore, the system robustness against load uncertainty and input disturbances as well as the voltage reference tracking are evaluated, and the proposed structure is compared with a PI-PI structure. Manuscript profile

Open Access Article

26 - A New Non-Isolated Buck-Boost DC-DC Converter with Wide Voltage Conversion Range
M. Heydari h. khoramikia Seyed Mohammad Dehghan

In this paper, a new wide-input-wide-output non-isolated buck-boost DC-DC converter is presented. The proposed converter has continuous current and is able to buck and boost the input voltage with shorter duty-cycles of the power switch compared to conventional buck-boo More

In this paper, a new wide-input-wide-output non-isolated buck-boost DC-DC converter is presented. The proposed converter has continuous current and is able to buck and boost the input voltage with shorter duty-cycles of the power switch compared to conventional buck-boost converters. A smaller duty cycle for a given voltage gain translates to lower current ripple of the inductors, reduced conduction losses, alleviated voltage stresses of the semiconductor switches and improved overall efficiency. The proposed converter also benefits from a simpler structure and control scheme. In this paper, the steady state operation of the proposed converter is investigated under both continuous conduction mode (CCM). The simulation and experimental results confirm the validity of theoretical analysis as well as the proper performance of the proposed converter. Manuscript profile

Open Access Article

27 - Non-Isolated DC / DC Converter with High Voltage Gain and Appropriate Efficiency in High Transfer Power with New Soft Switching Structure
Omid sharifiyana majid dehghani Ghazanfar Shahgholian S.M. Mehdi Mirtalaei Masoud Jabbari

One of the main limitations of using renewable energies for electricity generation is the low output voltage of power plants with renewable energies. Therefore, the design of a converter with higher gain voltage and higher efficiency is important in the use of renewable More

One of the main limitations of using renewable energies for electricity generation is the low output voltage of power plants with renewable energies. Therefore, the design of a converter with higher gain voltage and higher efficiency is important in the use of renewable energies. In this paper, a new topology that simultaneously has the structure of a boost converter can minimize switching losses by conventional soft switching methods and is also able to reduce voltage stress on diodes and switches Keep to an acceptable level. A simple boost converter can Increase the output voltage significantly by adding a parallel branch by generating a series resonance and enables zero voltage switching at the same time. Suggested converter without adding active element to converter with simple non-isolated structure at 500 watts and 385 volts it has a voltage gain factor of about 10.8 and efficiency of over 93%. The results show the performance simulation of the proposed converter for different performance modes. Manuscript profile

Open Access Article

28 - Improving the Transient Stability of Grid Connected Converter During Severe Voltage Drop by Virtual Impedance
Omid Abdoli E. Gholipour R. Hooshmand

With the rise in the penetration of inverter based distributed energy sources, grid codes say that converters should not be disconnected during the fault. These sources should also help the grid by reactive power injection. Power system grids are resistive inductive and More

With the rise in the penetration of inverter based distributed energy sources, grid codes say that converters should not be disconnected during the fault. These sources should also help the grid by reactive power injection. Power system grids are resistive inductive and the converter may be unstable during the fault. Converters use phase locked loop (PLL) to synchronize with the grid. PLL is not able to be stable during severe voltage drop, so converters cannot ride through the fault and should be disconnected. In this paper a novel method based on virtual impedance is proposed to maintain the synchronization during severe voltage drop. This method needs grid impedance estimation and virtually connects the converter to a point that has a stronger connection. By this novel method, during voltage drop, the converter stays connected to the grid and injects reactive power. Simulation results in MATLAB verify the ability of proposed method in improving the transient stability of converter. Manuscript profile

Open Access Article

29 - Reduction of Electrical Losses of Flying-Capacitor Modular Multilevel Converter (FC-MMC) in Electric Drive Application
Ahmad Bagheri H. Iman-Eini

The flying-capacitor modular multilevel converter (FC-MMC) has been introduced as a hardware development of the conventional MMC with the aim of reducing the cell capacitor ripple voltage in the application of electrical drive at low speeds. The capacitor ripple voltage More

The flying-capacitor modular multilevel converter (FC-MMC) has been introduced as a hardware development of the conventional MMC with the aim of reducing the cell capacitor ripple voltage in the application of electrical drive at low speeds. The capacitor ripple voltage of the cells in this converter is reduced only by injecting high frequency circulating current between the arms. In the conventional control method of this converter, the circulating current component is injected with the aim of complete elimination of the voltage ripple at low frequencies, which leads to an unnecessary increase of the current amplitude in the converter arms. In this paper, the converter control system is modified by finding the relationship between the cell capacitor voltage ripple and the high frequency circulating current amplitude. Then, by injecting the appropriate amplitude of the circulating current, the voltage ripple is controlled in an acceptable range. It is shown that by partial compensation (instead of full elimination of the voltage ripple), in addition to reducing the amplitude of the arm currents, the losses of the electrical system are significantly reduced. The results of simulations and experiments confirm the successful performance of the proposed method. Manuscript profile

Open Access Article

30 - Proposing a New High-Gain Switched-Capacitor Pulsed-Power Converter Using Low Input Voltage Source
sogand nikkhah Mohammad Rezanejad Reza khosravi

In this paper a new topology of pulsed-power converter to generate high-voltage pulses by low-input source is proposed. The proposed high step-up converter can generate high output voltage with few number of elements and stages. This converter which is based on switch-c More

In this paper a new topology of pulsed-power converter to generate high-voltage pulses by low-input source is proposed. The proposed high step-up converter can generate high output voltage with few number of elements and stages. This converter which is based on switch-capacitor structure is self-balanced and can be used in portable pulsed power supply. To show the validity of the proposed converter operation, a prototype of the proposed topology in the laboratory was constructed. The results show proper operation of the converter. Manuscript profile

Open Access Article

31 - Fault Tolerant Control of DFIG Wind Turbine Back-to-Back Converter Based on Developed Sliding Mode Method
mehrnoosh Kamarzarrin Mohammad Hossein Refan پرویز امیری

Fault detection and tolerable control of wind turbine increases its reliability and availability. One of the electrical components of the wind turbine with a high error rate is the power converter. In this paper, a new method for fault tolerant (FT) control of the wind More

Fault detection and tolerable control of wind turbine increases its reliability and availability. One of the electrical components of the wind turbine with a high error rate is the power converter. In this paper, a new method for fault tolerant (FT) control of the wind turbine back-to-back converter based on Dual Feed Induction Generator (DFIG) is presented. When a open circuit fault occurs in each of the IGBTs of the wind turbine converter, the performance of the converter is distorted and part of the current signal of each leg of the converter is lost. The classical controller cannot completely correct this change in current behavior, and for this reason, it has an abnormal performance. As a result, power generation will be accompanied by many fluctuations. In order to compensate, a new method based on sliding mode control is presented in this article. First, when an error occurs, the fault detection system identifies the faulty leg, and after reconfiguring the hardware, the proposed control system based on sliding mode control replaces the classic control system and switching operation. The fault detection method presented in this article is based on artificial neural network and it was developed based on matching with the functional parameters of the wind turbine. The proposed FT method is evaluated using a hardware simulator in a laboratory loop with a 90 kW DFIG generator. The experimental results show the proper accuracy of the fault detection method and on the other hand, the proposed FT method was able to compensate the open circuit fault of the IGBT. Manuscript profile

Open Access Article

32 - Integrated Modeling of Bidirectional Solid-State Transformers: Rectifier, DC to DC Converter and Inverter Stages
hamed molla-ahmadian morteza shafiei javid khorasani

: One of the new and growing equipment in modern power networks is solid state or power electronic transformer. These types of transformers are based on power semiconductor switches and high frequency transformers. Compared to traditional transformers, it has several ca More

: One of the new and growing equipment in modern power networks is solid state or power electronic transformer. These types of transformers are based on power semiconductor switches and high frequency transformers. Compared to traditional transformers, it has several capabilities such as the ability to operate with input voltage variations in amplitude and frequency, automatic regulation of output voltage and input power factor correction. The investigated transformer has the ability to transfer power in both directions and has three stages, including the rectifier, the middle stage and the inverter stage. This transformer has a large number of semiconductor switches and its modeling, analysis, design and simulation is difficult and complex. In particular, real-time simulation of these transformers with conventional models is not possible. In these cases, the use of averaging theory seems to be the appropriate solution. In this paper, the averaging theory is applied to a solid-state transformer and its modeling is done in a simple and powerful way with the ability to study real-time, transient and steady states performance. The proposed modeling includes differential equations and equivalent circuits and offers an integrated transformer model with the ability to study the interaction between stages as a part of power system. The presented models are used in simulation of smart grids, DC microgrids and connection of distributed generation sources to the grid, as well as analysis and design of solid-state transformer behavior in areas such as renewable energies and electrical transportation. In addition to the proposed modeling, the closed-loop control structure has been implemented for all three stages. Transformer simulation is performed by implementing differential equations in SIMULINK/MATLAB software and verified the proposed model. Manuscript profile

Open Access Article

33 - Improvement of Harmonic Losses and Power Quality Due to Matrix Converter Switching in Bidirectional Feeding Induction Generator Using Passive Hybrid Filter
neda ghaderi hoda naderi Mohammad عابدینی محمدحسن مرادی

<p>In two-way feeding induction generators, the stator coils connect directly to the grid, while the rotor coils connect through power electronic converters. Back-to-Back (BTB) converters are commonly used but suffer from high losses, size, and weight due to their two-s More

<p>In two-way feeding induction generators, the stator coils connect directly to the grid, while the rotor coils connect through power electronic converters. Back-to-Back (BTB) converters are commonly used but suffer from high losses, size, and weight due to their two-stage structure and DC link capacitor. This paper proposes replacing BTB converters with matrix converters for improved efficiency and compactness. The proposed method utilizes direct power control in the matrix converter for superior tracking of reference values during changes in both reference and turbine power. However, power electronic converters can introduce harmonics and power fluctuations. To address this, a passive hybrid filter is employed at the converter's input and output. This filter reduces active and reactive power fluctuations, improves Total Harmonic Distortion (THD), and enhances overall power quality. Additionally, the matrix converter's fast dynamic response to reference power changes eliminates the need for complex current control loops, resulting in a simpler structure with minimal calculations. The paper compares the performance of the proposed method (matrix converter with filter) against scenarios with and without a filter. The results demonstrate the filter's effectiveness and superiority in achieving optimal performance.</p> Manuscript profile

Open Access Article

34 - Bounded Delays in Switching Signal for Switched Affine Systems
Arman Sehatnia F. Hashemzadeh Mahdi Baradarannia

In this article, the consequence of the presence of delay in the switch signal for switched affine systems is investigated. First, based on the principles of stability, the process of extracting the switch law as the only control input is examined, then by presenting th More

In this article, the consequence of the presence of delay in the switch signal for switched affine systems is investigated. First, based on the principles of stability, the process of extracting the switch law as the only control input is examined, then by presenting the practical stability issue for switched systems, more realistic view of these systems is proposed. The main focus of the article will be on the effect of delay in the transmission of switching signal information. The presence of limited delay in switching signal is usually caused by high volume of switching law calculations or any cyber attacks. In this paper, the practical Lyapunov stability results related to the states before and after the presence of delay in switching signal for a linear switched affine system are compared analytically and simulated. The results of the comparison of these modes show that when the value of delay in switching signal increases, the ultimate limit of the error for system states becomes larger, and this means a decrease in the convergence of the system states. In this regard, the results implemented for a DC-DC power converter and the necessary comparisons are presented in the last chapter. Manuscript profile

Open Access Article

35 - Analysis and Implementation of a Step-Down DC-DC Converter with a New Control Method to Reduce Converter Losses
Mohamad Reza Banaei sajad gabeli sani

A step-down converter based on buck and buck-boost converters with a loss reduction technique is proposed in this paper. Utilizing non-electrolytic capacitors in the implementation of the proposed converter has resulted in an increase in circuit life and a reduction in More

A step-down converter based on buck and buck-boost converters with a loss reduction technique is proposed in this paper. Utilizing non-electrolytic capacitors in the implementation of the proposed converter has resulted in an increase in circuit life and a reduction in weight and volume. This paper compares the proposed converter to other buck converters. To increase the output efficiency of the converter in comparison to other structures, a new method based on determining the working duty-cycles has been employed to reduce the losses of the converter, resulting in an increase in the converter's output efficiency. In order to demonstrate the differences in efficiency between the proposed method and the conventional method, the efficiency of the converter has been calculated using real-world conditions and the output loss results have been compared. In addition, the proposed converter has a common ground with the input source and has a suitable reduction gain. Finally, this converter has been implemented as a PCB and tested with 100 watts of output power. Manuscript profile

Open Access Article

36 - Car pollution control using catalyst
khodadad behrozi

The emission of pollutants from vehicles is generally low, but the number of vehicles on the road increases, so the environmental pollution also increases. About 35% of CO, 30% of HC and 25% of NOx produced in the atmosphere are from the transportation sector. These pol More

The emission of pollutants from vehicles is generally low, but the number of vehicles on the road increases, so the environmental pollution also increases. About 35% of CO, 30% of HC and 25% of NOx produced in the atmosphere are from the transportation sector. These pollutants have adverse effects on the environment and human health. Greenhouse gas emissions from vehicles generally depend on the air-to-fuel ratio. Control techniques for exhaust emissions include engine modifications, fuel pretreatment, fuel additives, exhaust gas recirculation (EGR), positive crankcase ventilation (PCV), and the use of catalytic converters. A catalytic converter is a device that converts more toxic exhaust gases into less toxic pollutants. There are different types of catalysts used in the purification of car exhaust gases, such as catalysts of noble metals and basic metals, etc. The catalytic converter was effective and compatible in reducing harmful exhaust gas emissions so that it can be used in trucks, buses, cars, motorcycles and other equipped constructions. This article will discuss various types of recent advances in catalysts for controlling vehicle exhaust pollution. Manuscript profile

Open Access Article

37 - Investigating the performance of electronic transformers on the environment
Maziar Demory Nejad Mehrdad Mohadpur

During the last 30 and 40 years, TS transformer substations have evolved a lot, from the classic assembly in open areas, partition walls and outdoors, to the existing model, in order to increase human safety and material reliability, as well as significant progress. Ass More

During the last 30 and 40 years, TS transformer substations have evolved a lot, from the classic assembly in open areas, partition walls and outdoors, to the existing model, in order to increase human safety and material reliability, as well as significant progress. Assembly and space reduction, new results such as metal enclosures, prefabricated buildings, compact transformer substations and finally installed substations are also revolutionary. Due to society's increasing concern about the environment, the industry as a whole is rethinking the design and materials that may mean pollution, trying to replace them as much as possible with environmentally friendly communities. The inevitable development of society cannot and should not destroy the future of the earth. The time for sustainable development has come. So our work here today is a help in that sense. Manuscript profile

Open Access Article

38 - Comparison of FCS-MPC Predictive Control and Predictive Control Based on Lyapunov Theory in Seven-Level PUC Rectifier
Alimohammad Mohammadpour Behbid Mohammad Reza Alizadeh Pahlavani Arash Dehestani Kolagar Alireza Davari

In this paper, two predictive control methods for dual output multilevel rectifier are compared. The investigated structure is a seven-level PUC rectifier, which was selected based on high reliability and low cost. Increasing the number of input voltage levels helps to More

In this paper, two predictive control methods for dual output multilevel rectifier are compared. The investigated structure is a seven-level PUC rectifier, which was selected based on high reliability and low cost. Increasing the number of input voltage levels helps to reduce the amount of harmonics and consequently reduce the size of power filters. On the other hand, current conduction in this converter is performed continuously and the problems of current discontinuity such as complexity in analysis and the requirement to use large induction filters on the DC side are solved. First, the design is accomplished based on the FCS-MPC method and two different output voltages with ratios of 1 and 3 are obtained. Also, the control of output DC voltages and unity input power factor is well provided. Then, to achieve better stability, the MPC method based on Lyapunov theory has been utilized. In this method, the target variables are defined in the Lyapunov function and the cost function is derived from the same Lyapunov function. The advantages of this approach compared to the conventional MPC method are no need for gain adjustment, easier implementation and fewer sensors (the load current is estimated using the PUC7 rectifier mathematical model). The simulation of both FCS-MPC and predictive control based on Lyapunov method is carried out using Matlab/Simulink and the results of both methods are presented and compared with each other. Finally, it can be seen that in the Lyapunov-based method, the tracking of the reference current is smoother and with less fluctuations, and the seven-level rectifier voltage also has a more regular and sinusoidal waveform. Manuscript profile

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