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Marian K. Kazimierczuk - One of the best experts on this subject based on the ideXlab platform.

  • Analysis of Class-DE PA Using MOSFET Devices With Non-Equally Grading Coefficient
    IEEE Transactions on Circuits and Systems I: Regular Papers, 2019
    Co-Authors: Ali Lotfi, Marian K. Kazimierczuk, Hiroo Sekiya, Fujio Kurokawa, Akihiko Katsuki, Frede Blaabjerg
    Abstract:

    The design and analysis of a new operation-mode of the class-DE power amplifier (PA) using two MOSFETs with the non-equal grading coefficient is introduced. The PA uses the optimum Shunt Capacitance for each MOSFET to achieve zero voltage switching (ZVS) condition and wide range for the load-resistance point of view. As compared with the conventional class-DE PA, this configuration has low value of the series inductance that is reduced the power dissipation. A design procedure with intuitive curves is obtained that are implemented using a different grading coefficient for two MOSFETs. These criteria prepared an effective approach regardless of the fixed Shunt Capacitance for achieving ZVS condition. The desired operation of the class-DE PA is guaranteed by converging of design parameters and required output power. Moreover, non-similar switches provide reduced switch power dissipations and the number of the driving circuit PA. The simulation and experiment results are approved by implementing the outlined theoretical relationships for a fabricated class-DE PA at 4-MHz switching frequency and obtained 12.1-W output power.

  • Generalized Design Considerations and Analysis of Class-E Amplifier for Sinusoidal and Square Input Voltage Waveforms
    IEEE Transactions on Industrial Electronics, 2015
    Co-Authors: Mohsen Hayati, Marian K. Kazimierczuk, Ali Lotfi, Hiroo Sekiya
    Abstract:

    In this paper, analytical expressions and design equations are presented for a class-E amplifier with MOSFET nonlinear drain-source Capacitance and linear gate-drain parasitic Capacitance, along with external linear Shunt Capacitance. The class-E amplifier characteristics are presented as functions of the ratio of the sum of the external linear Shunt Capacitance and the MOSFET linear gate-drain Capacitance to the MOSFET drain-source junction Capacitance when the switch voltage is zero. Although the effect of the MOSFET linear gate-drain Capacitance is similar to that of the external linear Shunt Capacitance on the design of the class-E amplifier with a square input voltage, the difference between their effects should be considered for the sinusoidal input voltage, which is one of the most important suggestions in this paper. Additionally, analytical expressions of the output power capability is given, which is considerably affected by the external linear Shunt Capacitance. Two design examples are presented, taking into account as design specification the output power of 8.7 W and the operating frequency of 4 MHz, along with the PSpice-simulations and experimental waveforms.

  • ISCAS - Power efficiency calculation of class E amplifier with nonlinear Shunt Capacitance
    Proceedings of 2010 IEEE International Symposium on Circuits and Systems, 2010
    Co-Authors: Tadashi Suetsugu, Marian K. Kazimierczuk
    Abstract:

    Power efficiency of a class E RF power amplifier versus dc supply voltage V DD when the Shunt Capacitance of the class E amplifier is a nonlinear Capacitance with the grading coefficient m = 0.5 is obtained. In the calculation of power efficiency, switching loss due to non-zero turning on of the MOSFET, power loss due to forward voltage drop of the MOSFET body diode, and power loss due to MOSFET on-resistance are incorporated. It is found that the highest power efficiency is obtained at a lower dc supply voltage than the designed dc supply voltage, even though the circuit was designed to achieve the nominal operation at the designed dc supply voltage. The calculation was performed with Mathcad programming and the results were verified with Pspice simulations.

  • Power efficiency calculation of class E amplifier with nonlinear Shunt Capacitance
    Proceedings of 2010 IEEE International Symposium on Circuits and Systems, 2010
    Co-Authors: Tadashi Suetsugu, Marian K. Kazimierczuk
    Abstract:

    Power efficiency of a class E RF power amplifier versus dc supply voltage VDD when the Shunt Capacitance of the class E amplifier is a nonlinear Capacitance with the grading coefficient m = 0.5 is obtained. In the calculation of power efficiency, switching loss due to non-zero turning on of the MOSFET, power loss due to forward voltage drop of the MOSFET body diode, and power loss due to MOSFET on-resistance are incorporated. It is found that the highest power efficiency is obtained at a lower dc supply voltage than the designed dc supply voltage, even though the circuit was designed to achieve the nominal operation at the designed dc supply voltage. The calculation was performed with Mathcad programming and the results were verified with Pspice simulations.

  • ZVS operating frequency versus duty ratio of class E amplifier with nonlinear Shunt Capacitance
    2008 IEEE International Symposium on Circuits and Systems, 2008
    Co-Authors: Tadashi Suetsugu, Marian K. Kazimierczuk
    Abstract:

    The maximum operating frequency of the class E amplifier with nonlinear Shunt Capacitance depends on the transistor duty ratio. It varies with the duty ratio under zero- voltage switching (ZVS) and zero-derivative switching (ZDS) conditions at fixed values of the output power, dc supply voltage. Therefore, the design of the class E amplifier with given values of the Shunt Capacitance, the output power, dc supply voltage is possible by adjusting the operating frequency. The operating frequency has the maximum value when the duty ratio DON is approximately 0.36 at VDD/Vbi = 1 . It is also shown that the maximum operating frequency is higher when the dc supply voltage VDD is lower.

Tadashi Suetsugu - One of the best experts on this subject based on the ideXlab platform.

  • Effect on voltage dividing class E amplifier by parasitic Capacitances of drive circuit
    2017 IEEE 3rd International Future Energy Electronics Conference and ECCE Asia (IFEEC 2017 - ECCE Asia), 2017
    Co-Authors: Katsutoshi Hirayama, Tadashi Suetsugu, Hidenori Maruta, Fujio Kurokawa
    Abstract:

    This paper considers influence of voltage dividing class E amplifier by parasitic Capacitances of diode of connected to drive circuit. Voltage dividing class E amplifier can accommodate problem of class E amplifier because it is possible to divide peak switch voltage by connecting transistors in series. In this circuit, the source of transistor can't be connected to ground by connecting transistors in series. This problem is addressed by connecting a resistor and two diodes to each gate part of transistor. Namely, parasitic Capacitances of diode have an influence on Shunt Capacitance. However, previous analyses didn't consider the existence of parasitic Capacitances of diode of connected to the drive circuit. In this paper, influence of parasitic Capacitances of drive circuit are taken into consideration for a design. This paper derives the design formula of the Shunt Capacitance including the parasitic Capacitances. With this design formula, nominal operating circuit can be designed properly at the high operating frequency where a ZVS operation could not be achieved due to the parasitic Capacitance.

  • Switched capacitor discrete control ofvoltage dividing class E amplifier to achieve sub nominal operation
    2016 IEEE International Conference on Renewable Energy Research and Applications (ICRERA), 2016
    Co-Authors: Katsutoshi Hirayama, Tadashi Suetsugu, Yudai Furukawa, Takuya Shirakawa, Hidenori Maruta, Fujio Kurokawa
    Abstract:

    In this paper, we present the class E amplifier connecting the transistors in series, and some of connected transistors in series are constantly kept active, and rests are periodically controlled. In the proposed method, peak switch voltage of class E amplifier is reduced lower than conventional because Shunt Capacitance voltage is divided by connecting the transistors in series. Thus, peak switch voltage of the class E amplifier is able to divide depending on the number of transistors. As a conventional study, there is a method to perform of maintain the nominal operation by controlling Shunt Capacitance and resonant Capacitance in the class E amplifier when the load changes. For the reason, the sub nominal operation can be maintained when the load changes because the Shunt Capacitance can be controlled some of connected transistors in series are constantly kept active, rests are periodically controlled because it is possible to control the number of driving transistors.

  • Extended discrete control of class E amplifier in order to achieve nominal operation
    2014 International Power Electronics Conference (IPEC-Hiroshima 2014 - ECCE ASIA), 2014
    Co-Authors: Tadashi Suetsugu, Shotaro Kuga
    Abstract:

    This paper introduces concept of discrete control method of class E amplifier which keeps nominal operation for varying load resistance. In the proposed method, Shunt Capacitance and output resonant Capacitance are varied electronically by setting status of switches which are connected to Capacitances. Proposed method can keep nominal operation, i.e., ZVS and ZDS, both when load resistance is higher than the designed value and lower than the designed value. Operation of proposed circuit is verified with PSIM simulation.

  • ISCAS - Power efficiency calculation of class E amplifier with nonlinear Shunt Capacitance
    Proceedings of 2010 IEEE International Symposium on Circuits and Systems, 2010
    Co-Authors: Tadashi Suetsugu, Marian K. Kazimierczuk
    Abstract:

    Power efficiency of a class E RF power amplifier versus dc supply voltage V DD when the Shunt Capacitance of the class E amplifier is a nonlinear Capacitance with the grading coefficient m = 0.5 is obtained. In the calculation of power efficiency, switching loss due to non-zero turning on of the MOSFET, power loss due to forward voltage drop of the MOSFET body diode, and power loss due to MOSFET on-resistance are incorporated. It is found that the highest power efficiency is obtained at a lower dc supply voltage than the designed dc supply voltage, even though the circuit was designed to achieve the nominal operation at the designed dc supply voltage. The calculation was performed with Mathcad programming and the results were verified with Pspice simulations.

  • Power efficiency calculation of class E amplifier with nonlinear Shunt Capacitance
    Proceedings of 2010 IEEE International Symposium on Circuits and Systems, 2010
    Co-Authors: Tadashi Suetsugu, Marian K. Kazimierczuk
    Abstract:

    Power efficiency of a class E RF power amplifier versus dc supply voltage VDD when the Shunt Capacitance of the class E amplifier is a nonlinear Capacitance with the grading coefficient m = 0.5 is obtained. In the calculation of power efficiency, switching loss due to non-zero turning on of the MOSFET, power loss due to forward voltage drop of the MOSFET body diode, and power loss due to MOSFET on-resistance are incorporated. It is found that the highest power efficiency is obtained at a lower dc supply voltage than the designed dc supply voltage, even though the circuit was designed to achieve the nominal operation at the designed dc supply voltage. The calculation was performed with Mathcad programming and the results were verified with Pspice simulations.

Mostafa Jazaeri - One of the best experts on this subject based on the ideXlab platform.

  • realistic insights into impedance seen by distance relays of a sssc compensated transmission line incorporating Shunt Capacitance of line
    International Journal of Electrical Power & Energy Systems, 2015
    Co-Authors: Hamed Abdollahzadeh, Babak Mozafari, Mostafa Jazaeri
    Abstract:

    Abstract In practice, the series compensation is applied to medium-/long-length transmission lines. Such lines include significant Shunt Capacitance, neglecting of which is expected to noticeably influence the impedance seen by distance relays. Taking the Shunt Capacitance of a transmission line compensated by the static synchronous series compensator (SSSC) as well as other affecting factors into account, this paper derives precise mathematical expressions governing the apparent impedance seen by the distance relay of the line. Through the acquired expressions, the research conducts sensitivity studies considering different compensation scenarios and locations for the SSSC. The studies make an attempt to produce realistic insights into ideal tripping characteristics of the distance protection of the under studied line, and also into the susceptibility of the impedance seen to output parameters of the SSSC. In addition, the research’s findings well demonstrate the extent to which neglecting the Shunt Capacitance of the line would contribute to mis-operation of the distance relay.

Hamed Abdollahzadeh - One of the best experts on this subject based on the ideXlab platform.

  • realistic insights into impedance seen by distance relays of a sssc compensated transmission line incorporating Shunt Capacitance of line
    International Journal of Electrical Power & Energy Systems, 2015
    Co-Authors: Hamed Abdollahzadeh, Babak Mozafari, Mostafa Jazaeri
    Abstract:

    Abstract In practice, the series compensation is applied to medium-/long-length transmission lines. Such lines include significant Shunt Capacitance, neglecting of which is expected to noticeably influence the impedance seen by distance relays. Taking the Shunt Capacitance of a transmission line compensated by the static synchronous series compensator (SSSC) as well as other affecting factors into account, this paper derives precise mathematical expressions governing the apparent impedance seen by the distance relay of the line. Through the acquired expressions, the research conducts sensitivity studies considering different compensation scenarios and locations for the SSSC. The studies make an attempt to produce realistic insights into ideal tripping characteristics of the distance protection of the under studied line, and also into the susceptibility of the impedance seen to output parameters of the SSSC. In addition, the research’s findings well demonstrate the extent to which neglecting the Shunt Capacitance of the line would contribute to mis-operation of the distance relay.

  • Impact of Shunt Capacitance of a SSSC-compensated transmission line on performance of distance relays
    2013 IEEE Power & Energy Society General Meeting, 2013
    Co-Authors: Hamed Abdollahzadeh, Babak Mozafari, Arash Tavighi, José Martí
    Abstract:

    Taking the Shunt Capacitance of a transmission line, compensated by a static synchronous series compensator (SSSC), as well as other affecting factors into account, and in case of a single line to ground (SLG) fault when the compensator resides in the fault path, this paper derives a precise formula for the apparent impedance seen by the ground element of a distance relay. In the case where the SSSC is found at the local end and providing reactive power compensation of the line, ideal tripping characteristics of the relay are acquired for different degrees of compensation through the impedance formula. In addition, the research investigates the impact of ignoring the Shunt Capacitance of the line on the relay under and overreach.

Andrei Grebennikov - One of the best experts on this subject based on the ideXlab platform.

  • RWS - Exploring the Design Flexibility of the Class-E Power Amplifier with Shunt Capacitance and Shunt Filter
    2019 IEEE Radio and Wireless Symposium (RWS), 2019
    Co-Authors: Moïse Safari Mugisho, Andrei Grebennikov, Mury Thian, Denis G. Makarov, Vladimir G. Krizhanovski
    Abstract:

    The Class-E power amplifier (PA) with Shunt Capacitance and Shunt filter offers a unique design flexibility which can be exploited either to extend the maximum operating frequency of the PA or to allow the use of large active devices with high power handling capability. In this paper, a novel transmission-line load network is proposed to provide the drain of the active device with the required load impedances at the fundamental frequency as well as at even and odd harmonic frequencies. The concept is verified through simulations and measurements of a circuit prototype, which delivers a peak drain efficiency of 90.2%, a peak power-added efficiency of 82.7%, and a peak output power of 39.8 dBm at 1.37 GHz.

  • Exploring the Design Flexibility of the Class-E Power Amplifier with Shunt Capacitance and Shunt Filter
    2019 IEEE Radio and Wireless Symposium (RWS), 2019
    Co-Authors: Moïse Safari Mugisho, Andrei Grebennikov, Mury Thian, Denis G. Makarov, Vladimir G. Krizhanovski
    Abstract:

    The Class-E power amplifier (PA) with Shunt Capacitance and Shunt filter offers a unique design flexibility which can be exploited either to extend the maximum operating frequency of the PA or to allow the use of large active devices with high power handling capability. In this paper, a novel transmission-line load network is proposed to provide the drain of the active device with the required load impedances at the fundamental frequency as well as at even and odd harmonic frequencies. The concept is verified through simulations and measurements of a circuit prototype, which delivers a peak drain efficiency of 90.2%, a peak power-added efficiency of 82.7%, and a peak output power of 39.8 dBm at 1.37 GHz.

  • Generalized Class-E Power Amplifier With Shunt Capacitance and Shunt Filter
    IEEE Transactions on Microwave Theory and Techniques, 2019
    Co-Authors: Moïse Safari Mugisho, Andrei Grebennikov, Denis G. Makarov, Vladimir G. Krizhanovski, Yulia V. Rassokhina, Mury Thian
    Abstract:

    This paper presents a generalized analysis of the Class-E power amplifier (PA) with a Shunt Capacitance and a Shunt filter, leading to a revelation of a unique design flexibility that can be exploited either to extend the maximum operating frequency of the PA or to allow the use of larger active devices with higher power handling capability. The proposed PA fulfills zero voltage switching (ZVS) and zero voltage derivative switching (ZVDS) conditions, resulting in a theoretical dc-to-RF efficiency of 100%. Explicit design equations for the load-network parameters are derived, and the analytical results are confirmed by harmonic-balance simulations. Two PA prototypes were constructed with one designed at low frequency and the other at high frequency. The first PA, which employs a MOSFET and a lumped-element load-network, delivered a peak drain efficiency (DE) of 93.3% and a peak output power of 37 dBm at 1 MHz. The second PA, which employs a GaN HEMT and a transmission-line (TL) load-network to provide the drain of the transistor with the required load impedances at the fundamental frequency as well as even and odd harmonic frequencies, delivered a peak DE of 90.2% and a peak output power of 39.8 dBm at 1.37 GHz.

  • Effect of Shunt Capacitances on Performance of Current-Mode Class-DE Power Amplifier at Any Active Time
    IEEE Transactions on Power Electronics, 2018
    Co-Authors: Akram Sheikhi, Andrei Grebennikov, Abdolali Abdipour, H. Hemesi
    Abstract:

    In this paper, a current-mode Class-DE (CMCDE) power amplifier is presented. The CMCDE with linear Shunt Capacitance under zero-current switching (ZCS) and zero current-derivative switching (ZCDS) conditions at any active time is analyzed, simulated, and fabricated. An analytical theory along with the design simulation and verification by experimental results at active time $\tau _{d}= \pi / 2$ are given. It was shown that the peak switch voltage can be adjusted with active time $\tau _{d}$ . The proposed amplifier offers several desirable features, such as simple structure and possibility to include the parasitic inductance and Shunt Capacitance of the mosfet into a load network, so that ZCS condition is maintained. The results show that the switch voltage and current obtained in CMCDE amplifier are inversed in comparison to the voltage-mode Class-DE (VMCDE) amplifier by using a simple output matching network and series inductance. Also, we could control the harmonics in one resonator in comparison to multiple resonators used in some high-efficiency power amplifiers. The measured maximum drain efficiency of 88% and power gain of 22 dB at 42-dBm output power was obtained at 4 MHz for CMCDE amplifier at active time $\tau _{d}= \pi / 2$ .

  • high efficiency class e power amplifier with Shunt Capacitance and Shunt filter
    IEEE Transactions on Circuits and Systems, 2016
    Co-Authors: Andrei Grebennikov
    Abstract:

    An analysis of a novel single-ended Class-E mode with Shunt Capacitance and Shunt filter with explicit derivation of the idealized optimum voltage and current waveforms and load-network parameters with their verification by frequency domain simulations with 50% duty ratio is presented. The ideal collector voltage and current waveforms demonstrate a possibility of 100% efficiency. The circuit design with transmission lines at 2.14 GHz is discussed and analyzed. In order to reduce the voltage peak factor, the load network parameters can be rearranged to correspond to Class-E/F 3 mode by providing a short-circuit condition at the third harmonic when the second-harmonic tank is connected in series to the Shunt filter. Broadband capability of a Class-E mode with Shunt filter using reactance compensation technique has been demonstrated by two examples, one with lumped elements and the other with transmission-line elements. The test board of a transmission-line broadband Class-E GaN HEMT power amplifier with Shunt filter was measured and high-performance results with the output power of around 41 dBm, average drain efficiency of 68%, and power gain of about 9 dB were achieved across the frequency band from 1.4 to 2.7 GHz.