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Author

S.R.H. Amrei

Bio: S.R.H. Amrei is an academic researcher from Harbin Institute of Technology. The author has contributed to research in topics: Buck converter & Variable structure system. The author has an hindex of 2, co-authored 4 publications receiving 8 citations.

Papers
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Proceedings ArticleDOI
01 Jan 2005
TL;DR: A new control strategy by compromising both schemes and derivation of dynamic current reference is proposed, analyzed and simulated and considerations for realization with DSP controllers are addressed.
Abstract: DC/DC switching converters have been used in many applications in recent years. The sliding mode control based on VSS (variable structure system) theory has been examined for all switch mode converter types, whilst current mode (CM) control scheme is particularly applied to DC/DC converters. In this paper, a new control strategy by compromising both schemes and derivation of dynamic current reference is proposed, analyzed and simulated. Moreover, considerations for realization with DSP controllers are addressed

3 citations

Proceedings ArticleDOI
14 Dec 2005
TL;DR: In this paper, a non-linear modulator concept is proposed to describe the generation of harmonics and interharmonics in generalized power converters, and the analytical model is concluded and analyzed for conventional d-q rotating reference frame controller in VSI converter.
Abstract: The effects of interharmonics, which are defined as non-integer multiples of fundamental or switching frequencies in power utility connected VSI/CSI systems, are different from integer harmonics. A new approach is proposed in this paper based on the "non-linear modulator" concept to describe the generation of harmonics and interharmonics in generalized power converters. Subsequently, the analytical model is concluded and analyzed for conventional d-q rotating reference frame controller in VSI converter. Moreover, effects of feedback control strategy and additional compensation blocks are considered. Analysis validation is also confirmed by simulation results.

3 citations

Proceedings ArticleDOI
14 Dec 2005
TL;DR: A new control strategy by compromising both schemes advantages and avoiding their drawbacks is proposed, analyzed and simulated; and derivation of a dynamic current reference is also carried out.
Abstract: DC/DC switching converters have been used in many applications in recent years The sliding mode control based on VSS (variable structure system) theory has been examined for all switch mode converter types, whilst current mode (CM) control scheme is particularly applied to DC/DC converters However, these control strategies can't compensate for large load current and input voltage variations In this paper, a new control strategy by compromising both schemes advantages and avoiding their drawbacks is proposed, analyzed and simulated; and derivation of a dynamic current reference is also carried out Moreover, considerations for realization with DSP controllers are addressed

2 citations

Proceedings ArticleDOI
01 Jan 2005
TL;DR: A new approach is proposed based on the non-linear modulator concept; and the analytical model is derived and discussed for commonly used control scheme of d-q reference frame for generalized power converters.
Abstract: Interharmonics are defined as non-integer multiplies of fundamental or switching frequencies and have several different effects in PCC connected VSI/CSI systems compared to known harmonics In order to describe the generation of harmonics and interharmonics in generalized power converters, a new approach is proposed based on the non-linear modulator concept; and the analytical model is derived and discussed for commonly used control scheme of d-q reference frame Several effects of feedback control and compensation blocks are considered, analyzed and simulated for the analysis validation

1 citations


Cited by
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Journal ArticleDOI
TL;DR: In this article, a thorough review on power DC/DC converters with MPPT algorithm is presented, and the design and optimization of different parameters are addressed systematically, while future challenges and focusing trends are briefly described.
Abstract: Over the last few decennia, power DC/DC converters have been the subject of great interest due to its extensive increment of utilization in different applications. A thorough review on recent developed power DC/DC converters is presented in this paper. The study is focused on the topologies in different applications such as renewable energy, automobile, high-voltage and medium-voltage DC power systems, telecommunication, etc. In addition, an overview of the modulation techniques, the state-of-the-art of control strategies of well-established converters are discussed. Photovoltaic (PV) systems as the noticeable renewable energy resources generally suffer from poor conversion efficiency with instability and intermittent characteristics. Therefore, DC/DC converter with Maximum Power Point Tracking (MPPT) algorithm is essential to ensure maximum available power harnessed from the PV. Important features of DC/DC converters with MPPT are also figured with various performances. Furthermore, the design and optimization of different parameters are addressed systematically. Finally, the researcher’s future challenges and focusing trends are briefly described. For the next-generation converters design and applications, these are considered in details, and will provide useful framework and point of references.

193 citations

Journal ArticleDOI
TL;DR: In this paper, a new multi-output DC/DC converter topology that has step-up and step-down conversion capabilities is presented, where several output voltages can be generated and can be used in different applications such as multi-level converters with diode-clamped topology or power supplies with several voltage levels.
Abstract: This study presents a new multi-output DC/DC converter topology that has step-up and step-down conversion capabilities. In this topology, several output voltages can be generated and can be used in different applications such as multi-level converters with diode-clamped topology or power supplies with several voltage levels. Steady-state and dynamic equations of the proposed multi-output converter have been developed; these can be used for steady state and transient analysis. Two control techniques have been proposed for this topology, based on constant and dynamic hysteresis band height control, to address different applications. Simulations have been performed for different operating modes and load conditions to verify the proposed topology and its control technique. Additionally, a laboratory prototype is designed and implemented to verify the simulation results.

51 citations

Journal ArticleDOI
TL;DR: In this article, a high pass filter in series with the current sensor in current mode control (CMC) is proposed to achieve improved output impedance without using an integral controller, and the closed loop DC gain of a CCM buck converter is shown to be almost independent of the load resistance.
Abstract: Current mode control (CMC) though offers improved line regulation, phase margin and high bandwidth suffers from high output impedance. Although load regulation can be improved by incorporating an integral gain, it reduces the phase margin and increases the overshoot. The objective of this paper is to achieve improved output impedance without using an integral controller. Incorporating a high pass filter in series with the current sensor in CMC, the closed loop DC gain of a CCM buck converter is shown to be almost independent of the load resistance, thus improving load regulation using a proportional controller only. Improved features of CMC are also retained. Following VMC modeling approach, we develop a method to obtain the small signal model of the proposed scheme, and extended to CMC with an accurate low frequency characterisation. The proposed scheme is implemented on a buck converter, and the theoretical results are validated by experiments.

2 citations

Proceedings ArticleDOI
27 Mar 2009
TL;DR: In this article, the relationship between voltage fluctuation and inter-harmonics in distribution network based on modulation theory is investigated and verified by Matlab/Simulink simulation and physical tests.
Abstract: This paper presents an investigation into the relationship between voltage fluctuation and inter-harmonics in distribution network based on modulation theory. It is verified by Matlab/Simulink simulation and physical tests. The modulation theory, commonly used for analysis of harmonics, is used to analyze the inter-harmonics. A switching function of a rectangle waveform is used to describe a diode or thyristor's commutation status. The input current and output voltage of the rectifier can be described by the final waveforms of some sine function modulated by the switching function. And the inter-harmonics characteristics can be obtained by the Fourier analysis of these waveforms. It can be proved that if there are some fluctuations in the voltage source, there will be abundant inter-harmonics in the current. In order to investigate the validity of analysis and simulation, the physical experiments are finished with electric interruption generator (IG).

1 citations