Mehdi Narimani

Mehdi Narimani

McMaster University

H-index: 34

North America-Canada

About Mehdi Narimani

Mehdi Narimani, With an exceptional h-index of 34 and a recent h-index of 29 (since 2020), a distinguished researcher at McMaster University, specializes in the field of Power Electronics, Multilevel Converters, Ultra-Fast Chargers, High-Power Converters, Motor Drives.

His recent articles reflect a diverse array of research interests and contributions to the field:

A Co-Planar Transformer with Ultra-Low Parasitic Capacitance for EV Chargers

Fault-Tolerant SRM Drives—A Review

Integrating OFDM Into Switching Power Supplies for Visible Light Communications

Multi-Source Dual Active Bridge DC/DC Converter for More Electric Aircraft

Thermal-Electrical Modeling and Co-Optimization of a Half-Bridge Power Module with Silver-Sintered Molybdenum Packaging

A New Approach to Reduce DC-Bus Capacitance in Regenerative CHB Motor Drives

Overmodulation of Six-Phase Cascaded-CSI Using Optimal Harmonics Injection

High efficiency llc resonant converter with wide output range of 200–1000 v for dc-connected evs ultra-fast charging stations

Mehdi Narimani Information

University

McMaster University

Position

Assistant Professor of Electrical Engineering

Citations(all)

7578

Citations(since 2020)

4425

Cited By

4431

hIndex(all)

34

hIndex(since 2020)

29

i10Index(all)

75

i10Index(since 2020)

70

Email

University Profile Page

McMaster University

Mehdi Narimani Skills & Research Interests

Power Electronics

Multilevel Converters

Ultra-Fast Chargers

High-Power Converters

Motor Drives

Top articles of Mehdi Narimani

A Co-Planar Transformer with Ultra-Low Parasitic Capacitance for EV Chargers

Authors

Omar Zayed,Ahmed Elezab,Mehdi Narimani

Journal

IEEE Transactions on Transportation Electrification

Published Date

2024/4/4

The rising popularity of Planar Transformers (PTs) in isolated power converters for applications like electrified transportation, and electric vehicle (EV) chargers is driven by their compact design, high power density, and precise manufacturing. However, traditional PTs suffer from elevated inter-winding and intra-winding capacitance due to the extensive surface overlap in their flat winding structure. This high parasitic capacitance can lead to voltage overshoot, ringing, and reduced noise immunity, impacting the converter’s regulation capability. To address these challenges and optimize PT performance for higher frequencies, a new co-planar transformer (CPT) is introduced. The CPT minimizes surface overlap by siting the primary and secondary windings on the same plane, leveraging an ultra-flat conductor thickness. This design reduces both inter- and intra-winding capacitance without compromising winding area …

Fault-Tolerant SRM Drives—A Review

Authors

Nasir Ali,Mehdi Narimani

Published Date

2024/4/23

Fault tolerance in electric motor drives has been extensively studied due to their widespread usage in safetycritical applications, including more/all-electric aircraft and electric vehicles. SRMs are renowned for their high robustness and excellent fault tolerance. However, they are not immune to faults, and a potential fault in any part of the motor drive could have serious implications for the system, even may lead to unexpected shutdown if the fault is not promptly remedied. The power converter is a key component and the most vulnerable to failure, as reported for 35% of the drive faults. Fault tolerance has typically been achieved through a combination of hardware and software reconfigurations. However, due to the simple structure of the standard asymmetrical half-bridge (AHB) converter, hardware reconfiguration is more commonly used to remediate converter faults. Consequently, fault tolerance adds cost and …

Integrating OFDM Into Switching Power Supplies for Visible Light Communications

Authors

Alireza Barmaki,Mehdi Narimani,Steve Hranilovic

Journal

IEEE Transactions on Circuits and Systems I: Regular Papers

Published Date

2024/4/19

Visible light communications (VLC) is a promising technology that combines the ubiquity of illumination devices with broadband communication to provide connectivity. The most recent VLC communication standards specify orthogonal frequency division multiplexing (OFDM) as the underlying modulation due to its spectral efficiency and compatibility with existing broadband modems. However, a key challenge remains in realizing VLC modulators capable of generating OFDM signal compatible with the primary illumination function, while ensuring the efficacy of the luminaires. In this paper, a novel method is proposed to integrate OFDM modulation into a switching power supply. Commutating diodes in the DC/DC converter are replaced by light-emitting diodes (LEDs) which are used for communication while the larger illumination string of LEDs is left unmodulated preserving the quality of illumination and luminaire …

Multi-Source Dual Active Bridge DC/DC Converter for More Electric Aircraft

Authors

Mohamed I Hassan,Niloufar Keshmiri,Omar Zayed,Mehdi Narimani,Ali Emadi

Journal

IEEE Open Journal of Power Electronics

Published Date

2023/3/13

The topology proposed in this paper aims for a multiple sources/loads integration to improve the power density of the electrical power distribution system (EPDS) of the more-electric aircraft (MEA) architecture. The different operating modes of the proposed topology add flexibility to the system enabling power flow between different sources, while controlling the power supplied to the low voltage (LV) network on the aircraft. Better system utilization is achieved as compared to conventional solutions. The system stability is improved considering that the multi-source DAB (MSDAB) topology can be configured to stabilize the high-voltage DC (HVDC) bus in case of voltage sag. A battery charging configuration utilizing the magnetizing inductance of the transformer is proposed and discussed as one of the operating modes of the converter. The power flow to the low-voltage bus network is controlled by phase shifting the …

Thermal-Electrical Modeling and Co-Optimization of a Half-Bridge Power Module with Silver-Sintered Molybdenum Packaging

Authors

Yuhang Yang,Linke Zhou,Omar Zayed,Maryam Alizadeh,Doris Stevanovic,Mehdi Narimani,Ali Emadi

Journal

IEEE Transactions on Power Electronics

Published Date

2023/5/30

This article proposes a methodology of analytical modeling and optimization of power modules, especially compatible with modules with silver-sintered molybdenum (SSM) packaging or other insulated metal substrate types of packaging schemes. First, a decoupled Fourier-based thermal model is presented, which considers the barrier effect between substrate segments. Compared with the original Fourier-based model, it reduces the average error from 93.8% to 10.9%, when estimating the difference of junction temperatures ( ) for power modules with asymmetric substrates. Then, a stray inductance ( ) model is developed based on the partial inductance method and the actual current distribution, whose error is less than 12.1% when tested with example half-bridge SSM modules. Next, analytical models are combined with the particle swarm optimization algorithm to design a half-bridge power module with SSM …

A New Approach to Reduce DC-Bus Capacitance in Regenerative CHB Motor Drives

Authors

Ahmed Abuelnaga,Zhituo Ni,Sarah Badawi,Mehdi Narimani,Navid Zargari

Journal

IEEE Access

Published Date

2023/7/11

The cascaded H-bridge (CHB) converters with diode-front-end (DFE) structure have been widely adopted in non-regenerative high-power medium-voltage motor drives. In order to allow regenerative capability, the diode-front end (DFE) in each power cell can be replaced by an IGBT-based active-front-end (AFE) operating as a PWM rectifier. Due to the inherent instantaneous power unbalance in the AFE-based CHB power cells, the DC-bus capacitance needs to be increased to reduce DC-bus voltage ripples. To reduce the DC-bus capacitance, control degrees of freedom provided by the PWM rectifiers can be exploited to mitigate the DC-bus voltage ripples. This paper proposes a new controller for regenerative CHB converters to perform DC-bus voltage control and ripple mitigation while maintaining high dynamic performance and canceling low order harmonics at the grid side to meet the grid standards. The …

Overmodulation of Six-Phase Cascaded-CSI Using Optimal Harmonics Injection

Authors

Ahmed Salem,Mehdi Narimani

Journal

IEEE Access

Published Date

2023/1/30

This paper proposes a new and straightforward method to extend the modulation range of the six-phase cascaded current source inverter (CSI). The proposed technique employs vector space decomposition (VSD) to mitigate the inverter current harmonics and extend the linear modulation region by about 8%. For motor drive applications, increasing the fundamental output component can reflect higher torque production capability for the same drive size, given that thermal limits are not exceeded. The extension can be realized by injecting optimized xy harmonics while keeping the amplitude of the resulting phase currents under the maximum value. The method utilizes a look-up table of optimized values of the injected harmonics to extend the modulation range. The output filter capacitor effects are also studied in this paper, and a selection approach is introduced. Finally, the experimental results of a C-CSI …

High efficiency llc resonant converter with wide output range of 200–1000 v for dc-connected evs ultra-fast charging stations

Authors

Ahmed Elezab,Omar Zayed,Ahmed Abuelnaga,Mehdi Narimani

Journal

IEEE Access

Published Date

2023/3/31

DC-connected ultra-fast chargers consist of isolated DC/DC converter modules to provide the required charging profile. This paper proposes a charging module that interfaces with a fixed voltage DC-bus and covers a wide variety of electric vehicles (EVs) with battery voltages ranging from 200 to 1000 V. DC/DC converters for EVs charging has been discussed several times in the literature, however the DC-connected structure with fixed DC-bus voltage is rarely considered. This paper proposes a full-bridge LLC DC/DC converter module with a configurable secondary. This configuration extends the converter’s charging voltage range without adding stress on the resonant components or operating far from the unity gain point. Due to wide output range, the converter parameters are optimized using the time-domain analytical model to cover the required range without adding unnecessary circulating current that …

Transformer Design for Solid-State Transformer (SST)-Based EV Charging Station Applications

Authors

Eslam Abdelhamid Younis,Omar Zayed,Ahmed Elezab,Mohamed Ibrahim,Mehdi Narimani

Published Date

2023/6/21

Solid-state transformers (SSTs) are extensively studied nowadays to replace the line-frequency transformers (LFT) in various applications such as EV charging stations. The SST technology provides more controllability over the system, has the ability of power factor correction, and drastically reduces the size and weight of the whole system thanks to the medium-frequency transformer (MFT) used instead of LFT. In this paper, an optimized design tool is developed to design a 100 kW, 20 kHz transformer to be used in an SST-based EV charging station. The tool takes the system specifications as an input from the user then chooses the optimal core, number of turns, and Litz wire, to accelerate the design process. Two scaled-down 5 kW MFTs are implemented. The first was designed using the commonly used method in literature which ensures no saturation occurs in the core and limits the core losses to a certain value …

A new active front-end control for regenerative cascaded h-bridge motor drives with filter-less interfacing capability

Authors

Ahmed H Abuelnaga,Zhituo Ni,Sarah Badawi,Mehdi Narimani,Ahmed Sayed-Ahmed,Navid R Zargari

Journal

IEEE Transactions on Power Electronics

Published Date

2023/3/28

This article proposes a new active-front-end (AFE) control method for regenerative cascaded H-bridge (CHB) motor drives. Conventional CHB converters have dominated the market for the medium-voltage industrial motor drives. However, conventional CHB converters cannot provide regenerative capability. To enable regeneration; diode-front-ends in power cells are replaced with insulated-gate bipolar transistor (IGBT)-based pulsewidth modulation (PWM) AFEs. Despite the appealing dynamic performance of PWM AFEs, their integration to the CHB converters is not optimal. First, they introduce more semiconductor losses due to the high-frequency switching. Second, they introduce switching harmonics that are not cancelled by phase-shifting transformers. Therefore, they require additional harmonic filtering solutions to comply with grid harmonic standards. To resolve these challenges, this article proposes a new …

Investigation of a Kelvin-Source Connected SMD Silicon MOSFET and its Application in a High Current Full Bridge Synchronous Rectifier

Authors

Kyle Kozielski,Guvanthi Abeysinghe Mudiyanselage,Rachit Pradhan,Giorgio Pietrini,Ashish K Solanki,Parthasarathy Nayak,Mehdi Narimani,Ali Emadi

Published Date

2023/6/21

Auxiliary loads in an electric vehicle (EV) are in the order of 12–48 V since voltages above 50 V pose risks to the passengers. Power demand on auxiliary loads continues to expand due to increased computation requirements and load profiles. This requires development of power conversion systems that can manage high-currents efficiently. Construction of high current power conversion systems require multiple power switches (MOSFETs) in parallel, which reduce conduction losses. Efficiency can be further improved by incorporating Kelvin-source connections due to improved decoupling of the gate-source (G-S) and drain-source (D-S) loops in a MOSFET. This paper proposes a method to create a Kelvin-source connection in SMD silicon (Si) MOSFET packages with multiple source terminals. A comparison of switching energies between the conventional and proposed methods to highlight the improvements is performed. A …

A New Medium-Voltage Architecture for Ultra-Fast Electric Vehicle (EV) Charging Stations

Authors

Ahoora Bahrami,Mehdi Narimani

Published Date

2023/3/19

Range anxiety and lack of charging infrastructure are the two main barriers to the adoption of electric vehicles (EVs). These concerns can be resolved by using ultra-fast chargers or charging stations. The limitations of the traditional ultra-fast chargers include their low efficiency, high cost, and big footprints, as they are low-voltage (LV) coupled by line-frequency transformers. Researchers suggest the medium-voltage (MV) linked charging station as a solution to the drawbacks of traditional chargers by eliminating the line-frequency transformer and connecting directly to medium voltage. Various medium-voltage multilevel converters have been proposed to permit direct grid connection. However, drawbacks such as a large number of components and control complexity undermine the strength of medium-voltage linked stations. This paper presents a new MV-connected ultra-fast charging architecture that has fewer …

Fault Diagnosis of Cascaded H-Bridge Inverter Using Model Predictive Control

Authors

Yue Pan,Zhituo Ni,Ahmed Abuelnaga,Mehdi Narimani,Jose Rodriguez

Published Date

2023/6/16

This paper proposes a new fault detection and localization (FDL) algorithm based on modulated model predictive control (M 2 PC) method for Cascaded H-bridge (CHB) inverters. Model predictive control (MPC) algorithms have been widely applied in medium-voltage (MV) power converters for its advantages in dynamic performance and control of multiple objectives. However, it has some limits for multilevel topologies, including variable switching frequency and large computation burden. In addition, in cascaded H-bridge (CHB) multilevel inverters, fault detection and localization need to be incorporated into the control system to make it work normally when there is an open fault in power cells. This paper employs M 2 PC approach to calculate output voltage references with reduced computation burden in every sampling time. Also, M 2 PC features a fixed switching frequency in the system which helps improving …

Optimal Low Switching Frequency PWM Pattern for a Three-Level Neutral Point Clamped (NPC) Inverter

Authors

Aathira Karuvaril Vijayan,Battur Batkhishig,Mehdi Narimani,Ali Emadi

Published Date

2023/3/19

This paper proposes a mechanism of development of synchronous optimal pulse width modulation (PWM) generation for control of medium-voltage motor drives using multilevel inverters at low switching frequency. Multilevel inverters enable operation with multiple dc-link voltages while lowering total harmonic distortion (THD). Thermal losses limit the maximum switching frequency in high-power applications. As a result, the output waveforms are highly distorted. Synchronous optimal PWM (SOP) control allows for a low maximum switching frequency without sacrificing THD. The switching losses of power semiconductor devices are reduced when the switching frequency is low. A detailed explanation of an optimal control procedure is provided. The paper investigates the implementation of the SOP scheme in a three-level inverter topology and is compared with a two-level inverter. Also, the performance of SOP and …

Dead-Time Compensation for Model-free Predictive Control in Multilevel Inverters

Authors

Yue Pan,Zhituo Ni,Mehdi Narimani,Margarita Norambuena,Jose Rodriguez

Published Date

2023/6/16

Model predictive control (MPC) has been widely applied to various medium-voltage power converters due to its advantages in good dynamic performance and multi-objective control. However, the control algorithm requires the accurate model in the controlled system. As a result, the parameter mismatch between the actual model and control module leads to an undesired performance of MPC. Therefore, model-free predictive control (MFPC) has been developed in the literature to solve this issue. This approach uses a recursive least square (RLS) algorithm to estimate parameters in the model based on the measured values. In such systems, the dead-time makes the model nonlinear and leads to a poor prediction in the output currents and leads to the current distortion. In this paper, a dead-time compensation algorithm based on MFPC method is proposed to obtain a linear model and reduce the negative effects of …

RMS current minimization in a SiC-based dual active bridge converter using triple-phase-shift modulation

Authors

Negar Noroozi,Amirreza Poorfakhraei,Omar Zayed,Ahmed Elezab,Niloufar Keshmiri,Mehdi Narimani,Ali Emadi

Journal

IEEE Transactions on Industrial Electronics

Published Date

2022/9/12

In this article, we propose an optimization approach targeting rms current minimization in a dual active bridge (DAB) converter controlled by triple-phase-shift modulation. The proposed technique overcomes the drawbacks in the existing optimization solutions, namely, the high complexity of the time-domain optimization and the low accuracy of the fundamental harmonic minimization. A finite-component harmonic model is employed in the optimization approach to calculate the current harmonic values in the converter. The total rms current is approximated as the summation of dominant harmonics using the harmonic model. A numerical assessment technique is also proposed in this research that guarantees the accuracy of the adopted harmonic model. The proposed method ensures that the harmonic approximation error is less than a certain level over the operating range. The converter's optimal parameters are calculated …

Improving power density of a three-level ANPC structure using the electro-thermal model of inverter and a modified SPWM technique

Authors

Amirreza Poorfakhraei,Mehdi Narimani,Ali Emadi

Journal

IEEE Open Journal of Power Electronics

Published Date

2022/10/20

Multilevel inverter structures have become an interesting substitute for the well-known two-level inverters in a variety of applications due to their exceptional characteristics when compared to conventional inverters. One major issue regarding multilevel structures is the unequal junction temperature of the switches which deteriorates the power density and increase the cost of the inverter by reducing the maximum achievable output power with a given thermal model and cooling system. Hence, on account of the aggressive goals of power density and cost in a majority of power electronic applications, this article proposes a new technique for reducing the maximum junction temperature of switches in a three-level active neutral-point clamped (ANPC) inverter based on a junction temperature estimation method and a modified SPWM control scheme. This technique can ensure up to a 12% rise in the power density value …

Offline-Based SVM Techniques to Reduce Common-Mode Voltage of Six-Phase Cascaded-CSI

Authors

Ahmed Salem,Mehdi Narimani

Journal

IEEE Open Journal of Power Electronics

Published Date

2022/7/22

In this paper, space vector modulation (SVM) techniques are developed to operate the six-phase current-source inverters (CSI) while reducing the common-mode voltage (CMV) content associated with the switching of semiconductors. The CMV issue is a severe issue of high-power electronics converters that causes damage to electric drives and shortens their life span. Since the null states are the main contributor to CMV in SVM schemes, an optimum offline selection method is proposed in this paper for all the presented techniques. The SVM techniques discussed in this proposal are built on the renowned vector space decomposition (VSD) method. The modulation in all the techniques is based on studying the resultant CMV associated with all the possible switching states and then selecting the states that produce the lowest magnitude of CMV. Accordingly, the optimum sequences for the switching patterns are …

Systems and methods of multi-motor regenerative drive

Published Date

2022/9/6

A system is provided for driving multiple motors. The system includes multiple cascaded H-bridge (CHB) power inverters, a DC bus, and multiple neutral point converter/inverters. Each of the multiple CHB power inverters is connected to a respective motor at one or more AC terminals of the CHB power inverter. Each of the multiple CHB power inverters includes one or more DC terminals configured to receive DC power. Each of the multiple neutral point converter/inverters is connected to a respective CHB power inverter at one or more neutral terminals of the respective CHB power inverter and connected to the DC bus.

Converter topology comparison for a two-stage level-2 onboard charger in 800-V EV powertrains

Authors

Rachit Pradhan,Mehdi Narimani,Ali Emadi

Published Date

2022/10/17

The operating voltage of powertrains in Battery Electric Vehicles (BEVs) has witnessed an upward trend due to advantages in ultra-fast charging and reduction in run-time losses due to lower operating currents in the powertrain. Original Equipment Manufacturers (OEMs) such as Porsche, Audi, and Lucid Motors have introduced vehicles with powertrains operating from 800 V to 924 V. Due to increased switching losses at these voltage levels, the operation of DC-DC converters requires cascading of existing topologies or a multi-level operation. With increasing battery sizes, traditional Level-2 3.3 kW on-board chargers (OBCs) are deemed insufficient to fully complete a charge overnight. Thus, due to increasing voltage and power levels in commercial BEVs, this paper investigates the Grid to Vehicle (G2V) mode’s priority operating regions for a 11.5 kW Level-2 on-board charger in context of an 800 V powertrain. A …

See List of Professors in Mehdi Narimani University(McMaster University)

Mehdi Narimani FAQs

What is Mehdi Narimani's h-index at McMaster University?

The h-index of Mehdi Narimani has been 29 since 2020 and 34 in total.

What are Mehdi Narimani's top articles?

The articles with the titles of

A Co-Planar Transformer with Ultra-Low Parasitic Capacitance for EV Chargers

Fault-Tolerant SRM Drives—A Review

Integrating OFDM Into Switching Power Supplies for Visible Light Communications

Multi-Source Dual Active Bridge DC/DC Converter for More Electric Aircraft

Thermal-Electrical Modeling and Co-Optimization of a Half-Bridge Power Module with Silver-Sintered Molybdenum Packaging

A New Approach to Reduce DC-Bus Capacitance in Regenerative CHB Motor Drives

Overmodulation of Six-Phase Cascaded-CSI Using Optimal Harmonics Injection

High efficiency llc resonant converter with wide output range of 200–1000 v for dc-connected evs ultra-fast charging stations

...

are the top articles of Mehdi Narimani at McMaster University.

What are Mehdi Narimani's research interests?

The research interests of Mehdi Narimani are: Power Electronics, Multilevel Converters, Ultra-Fast Chargers, High-Power Converters, Motor Drives

What is Mehdi Narimani's total number of citations?

Mehdi Narimani has 7,578 citations in total.

What are the co-authors of Mehdi Narimani?

The co-authors of Mehdi Narimani are Maryam Saeedifard, Venkata Yaramasu, Farid Sheikholeslam, Mohammad Narimani.

    Co-Authors

    H-index: 46
    Maryam Saeedifard

    Maryam Saeedifard

    Georgia Institute of Technology

    H-index: 32
    Venkata Yaramasu

    Venkata Yaramasu

    Northern Arizona University

    H-index: 23
    Farid Sheikholeslam

    Farid Sheikholeslam

    Isfahan University of Technology

    H-index: 12
    Mohammad Narimani

    Mohammad Narimani

    Simon Fraser University

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