ENSET - Electrical and Computer Engineering

A new type of analog-to-digital conv ersion technique is presented in this paper. The i nterfacing hardware is a very simple nonlinear circuit with 1-bit modulated outpu t. As a implication, behind the hardware simplicit y retained is hidden a dreadful nonlinear duty-cycle modulation ratio. How ever, the overall nonlinear behavior embeds a suffi ciently wide linear range, for a

The novel digital-to-analog conversion technique studied in this paper, is founded on the digital duty-cycle modulation principle. It consists of a simple digital duty-cycle modulation program loaded in the flash memory of a microcontroller and an external analog low pass filter. Both pulse width and modulation period, simultaneously evolve according to the variation of the modulating input. Then, under the

In this paper, an automated dual IPCs 240 system for asymmetric power compensation, is designed from an analytical analysis of the power flow modes through the transmission line. Then, the ACL (automatic control logic) obtained consists of serial gates arrays of standard NAND/AND and OR operators.  It has been  implemented within Matlab/Simulink framework, and the simulation results obtained show the feasibility and great relevance of using the dual IPCs 240 technology, in power transmission networks  under normal and contingency conditions.

This research paper presents a synthesis approach of a digital optimal PID/LQR control system for DCM (duty-cycle cycle modulation) Buck converters. The step response of the DCM Buck converter is obtained under Multisim virtual simulation framework. The related data file is saved as *.SCP format, and imported into EditPad Lite7 editor, then exported as Matlab file to be processed. The transfer function of the DCM Buck converter is computed from the imported step response data. Then, using the zoh (zero order holder) discretization method with 100 ms resampling period, the z-transfer function of the DCM Buck converter is computed, and that of the analog optimal PID/LQR(linear quadratic regulator) controller is calculated using Tustin’s discretization technique. Furthermore, the step response of the related closed loop digital PID control system is simulated and compared to that of the original analog PID/LQR control system. The simulation results obtained are presented in order to sh...

In this paper, a novel building algorithmic scheme of DDCM (duty-cycle modulation) drivers is presented. It is modelled in the analog domain as a continuous time jump Markovian dynamic model, with a deterministic two-state Markov chain. An equivalent discrete jump dynamic model is computed using pole-zero matching transform. Then, the resulting digital iterative algorithm, consists of simple digital operators and structures. The proposed DDCM algorithm is simulated under Matlab framework, and implemented using Arduino IDE-C++ with uploading into an ESP32 system-on-chip (SoC) device. The monitoring device connected to the ESP32 via an USB communication cable is an Arduino/IDE virtual monitor. It is configured for 230400 bauds communication. A low cost ESP32-based DAC (digital-to-analog converter), is virtually implemented and well tested as a case study of the proposed new generation of DDCM drivers. Matlab digital simulation results and ESP32 processing and virtual monitoring result...

Nous presentons dans ce travail les origines physiques des sources independantes de bruit dans le CPA (preamplificateur de charge), puis avec a l’aide du PS (circuit de filtrage) ameliorer le S/B (rapport signal sur bruit). Dans la premiere partie, nous sommes interesses aux equations mathematiques permettant d’exprimer les differentes sources de bruit. La seconde partie de ce travail s’etend sur l’evaluation du bruit en termes de l’ENC (Equivalent Noise Charge). Par la suite, les etudes et simulations vont etre effectuees sur une technologie standard AMS CMOS 0.35µm et vont montrer que la miniaturisation est un atout. Aussi la valeur de l’ENC total est essentiellement dominee par l’expression du bruit thermique du transistor d’entree et cette derniere peut etre optimisee au detriment de la consommation en jouant sur I D . La valeur du courant de drain et le dimensionnement du transistor d’entree sont decisifs pour le bruit. Mots-cles : bruit, preamplificateur de charge, filtre CR-(...

A new type of analog-to-digital conversion technique is presented in this paper. The interfacing hardware is a very simple nonlinear circuit with 1-bit modulated output. As a implication, behind the hardware simplicity retained is hidden a dreadful nonlinear duty-cycle modulation ratio. However, the overall nonlinear behavior embeds a sufficiently wide linear range, for a rigorous digital reconstitution of the analog input signal using a standard linear filter. Simulation and experimental results obtained using a well tested prototyping system, show the feasibility and good quality of the proposed conversion technique.

This paper presents a review of a multipurpose duty-cycle modulation (DCM) technology . A brief introduction to switching modulation techniques is presented for the sake of well understanding of the innovative nature of the DCM architecture to be reviewed. The review is organized into numerous relevant application areas, including DCM-based instrumentation systems (i.e., DCM-based analog-to-digital conversion, DCM-based digital-to-analog conversion), DCM-based power electronic drivers (i.e. DCM-based Buck converters, DCM-based Boost converters, DCM-based power electronic inverters), and DCM-based digital transmission systems for arbitrary waveforms. Furthermore, the state-of-art evaluation  as well as new research opportunities about the multipurpose DCM technology, are provided in order to outline possible patentable DCM control systems, to be dedicated in the future to electrical and electronics engineering  markets .

This paper focusses on a novel optical fiber transmission system, with application on human ECG signal. Its novelty relies on the use of a simple and high quality DCM (duty-cycle modulation) circuit as the emitting interface. Then, the receiving interface device is a simple low-pass filter. A brief literature review on existing optical transmission systems is first presented, in order to better understanding the scientific scope of the proposed optical signal transmission system. In addition, the corresponding architectural model is designed from a mix of analytical and advanced numerical tools. Furthermore, a prototyping DCM-based optical fiber transmission system,  is implemented and well tested within Matlab/Simulink framework. As a relevant  finding, when testing the transmission of an ECG modulating signal, the overall  performance levels (e.g.,  SNR = 30 dB and RMS = 0.07),  as well as the  related hardware complexity and building cost, are more satisfactory compared to the ca...

The electronic instrument studied in this paper is a novel model of arbitrary waveform and wavelet generator. Unlike most programmable instruments designed for the same purpose with high complexity and great cost unfortunately, the proposed testing instrument is founded on a direct synthesis of arbitrary waveform signals including wavelets, from a basis of elementary analog signals. A novel arbitrary signal generation scheme is presented and well tested using virtual simulation and experimentation. Then, the predicted and experimental results obtained under a wide variety of testing conditions are presented, in order to show the great challenge of building a cheaper and high quality workbench for arbitrary signal generators.

AbstractA new type of multi-channel analog-to-digital conve rsion technique is presented in this research work. It is founded on the use of parallel duty-cycle modulatio n cells, each of which being used as an independent i erfacing circuit with 1-bit modulated output bit per channel. In addition, the set of modulated bits associated to the whole analog inputs, are simultaneous sampling and processing. The principl e and important properties of the proposed multi-channel A/D conversion are studied in depth in the paper. Then, an origina l 4-channel virtual oscilloscope is presented, in o rder to show a potential application of the proposed multi-channel analog-to -digital conversion technology in instrumentation engineering. Finally, a sample of signals acquired using that prototyping v irtual oscilloscope are presented .

In this paper, the chaotic phenomena are outlined in a class of simple NRO (negative resistance oscillator) or NCO (negative conductance oscillator) equivalently. Compared to most chaotic electronic schemes encountered in nonlinear dynamic systems theory and practice, the proposed class of chaotic circuits consists of simple piecewise linear NRO/NCO, involving a minimum number of building components and dynamic states. The feasibility of relevant chaotic phenomena is proven from the existence of their Van Der Pol dynamic models according to the least square estimation principle. Then, despite the simplicity of the 2nd order NRO/NCO, a relevant parameterization strategy associated with virtual simulation techniques, are used as key exploration means for creating relevant chaotic phenomena. Therefore, new strange chaotic attractors with 2D/3D shapes are created and presented. Moreover, a comparative study with a sample of existing chaotic NRO/NCO schemes, show that the proposed class ...

Estimation and optimization of the noise in detector readout front ends made by CMOS technology We present in this work the physical origins of independent noise sources in the front end circuit based on CMOS devices. In the first part, we are interested in the mathematic equations to express the different noise sources. The second part of this work has focused on its evaluation in terms of ENC (Equivalent Noise Charge). Studies and simulations are performed for a 0.35µm CMOS on standard technology AMS and shown that the design circuit can reduce the noise level of the CSA (readout front ends). ENC is dominated by the thermal noise of an input MOS and the thermal noise of the feedback resistor R f . We show several aspects of the noise optimization of the CSA regarding the optimum transistor width and the sensitivity of the ENC to this width.

This paper presents an original PC-Based Workbench for virtual instrumentation and automatic control. Its software platform results from a mix of Matlab Graphical User Interface (GUI) design and Matlab Executable (MEX) C++ programming. It is shown how a sophisticated custom MEX C++ control library, callable from Matlab GUI application, has been built from the C++ driver of an arbitrary data acquisition board. The varieties of simulation and experimentation modes provided include: digital-to-digital controls, digital-to-analog and analog-to-digital conversion, open loop control, and Matlab GUI/MEX controllers. A sample of simulated and experimental results obtained and presented, shows the great merit of the proposed well tested PC-based workbench in control engineering education. Key-Words: PC-Based Workbench, Virtual instrumentation, Automatic control, Matlab GUI, MEX-C++, mexFunction, data acquisition board, Advanced Programming, Matlab/MEX controllers.

In this paper, a novel SDCM (sine duty-cycle modulation) scheme for photovoltaic (PV) singlephase power inverter is presented. Unlike popular SPWM (sine pulse width modulation) strategies, the SDCM control scheme consists of a minimum number or building components, while offering a robust feedback control topology. The main DC power to be converted, is delivered by an upstream PV panel. Then, a SDCM circuit with appropriate basic modulation frequency, is used as a switching driver for power MOSFETs of a single phase H-bridge inverter. The merits of the proposed SDCM control scheme, are proven using analytical developments, followed by relevant virtual simulations conducted on a prototyping power inverter within Multisim software framework. Moreover, the virtual simulation results obtained are presented, in order to show the high quality of the proposed class of SDCM control schemes for PV Single-phase power inverters.

Abstract—This paper presents an optimal duty-cycle modulation (ODCM) scheme for analog-to-digital conversion (ADC) systems. The overall ODCM-Based ADC problem is decoupled into optimal DCM and digital filtering sub-problems, while taking into account constraints of mutual design parameters between the two. Using a set of three lemmas and four morphological theorems, the ODCM subproblem is modelled as a nonlinear cost function with nonlinear constraints. Then, a weighted least pth norm of the error between ideal and predicted frequency responses is used as a cost function for the digital filtering sub-problem. In addition, MATLAB fmincon and MATLAB iirlnorm tools are used as optimal DCM and least p norm solvers respectively. Furthermore, the virtual simulation scheme of an overall prototyping ODCM-based ADC system is implemented and well tested with the help of Simulink tool according to relevant set of design data, i.e., 3 KHz of modulating bandwidth, 172 KHz of maximum modulation f...