Reconfigurable of current-mode differentiator and integrator based-on current conveyor transconductance amplifiers

The reconfigurable of the differentiator and integrator based on current conveyor transconductance amplifiers (CCTAs) have been presented in this paper. The proposed configurations are provided with two CCTAs and grounded elements. The configurations can be operated in the differentiator and integrator by selecting external passive elements. The input and output currents have low and high impedances, respectively; therefore, the configurations can be cascaded without additional current buffer. The proposed configurations can be electronically tuned by external direct current (DC) bias currents, and it also has slight fluctuation with temperature. An application of universal filter is demonstrated to confirm the ability of the proposed configurations. The results of simulation with Pspice program are accordance with the theoretical analysis.

Modelling, Simulation, and Implementation of Effective Controller for KY Stepping Up Converter

This paper studies on a new Hybrid Posicast Control (HPC) for Fundamental KY Boost Converter (FKYBC) worked in Continuous Current Mode (CCM). Posicast is a feed-forward compensator. It reduces the overshoot in the step result of the flippantly damped plant. But the conventional controller approach is sensitive owing to the changes in the natural frequency. So, as to reduce this undesirable sensitivity and load potential control of FKYBC, a HPC is designed in this article. Structure of HPC is posicast with feedback loop. The independent computational time delay is the main design function of the posicast. The enactment of the FKYBC with HPC is confirmed at various operating regions by making the MATLAB/Simulink and experimental model. The posicast function values are implemented in Arduino Uno-ATmega328P microcontroller. The results of new HPC have produced minimal noise in control signal in comparison with traditional PID control.

Design and Analysis of a Voltage-Mode Non-Linear Control of a Non-Minimum-Phase Positive Output Elementary Luo Converter

The positive output elementary Luo (POEL) converter is a fourth-order DC–DC converter having highly non-linear dynamic characteristics. In this paper, a new dynamic output voltage feedback controller is proposed to achieve output voltage regulation of the POEL converter. In contrast to the state-of-the-art current-mode controllers for the high-order boost converters, the proposed control strategy uses only the output voltage state variable for feedback purposes. This eliminates the need for the inductor current sensor to reduce the cost and complexity of implementation. The controller design is accompanied by a strong theoretical foundation and detailed stability analyses to obtain some insight into the controlled system. The performance of the proposed controller is then compared with a multi-loop hysteresis-based sliding-mode controller (SMC) to achieve the output voltage-regulation of the same POEL converter. The schemes are compared concerning ease of implementation, in particular, the number of state variables and current sensors required for implementation and the closed-loop dynamic performance. Experimental results illustrating the features of both controllers in the presence of input reference and load changes are presented.

Electronically Adjustable Grounded Memcapacitor Emulator Based on Single Active Component with Variable Switching Mechanism

New current mode grounded memcapacitor emulator circuits are reported in this paper, based on a single voltage differencing transconductance amplifier-VDTA and two grounded capacitors. The proposed circuits possess a single active component matching constraint, while the MOS-capacitance can be used instead of classical capacitance in a situation involving the simulator working within a high frequency range of up to 50 MHz, thereby offering obvious benefits in terms of realization utilising an IC-integrated circuit. The proposed emulator offers a variable switching mechanism—soft and hard—as well as the possibility of generating a negative memcapacitance characteristic, depending on the value of the frequency of the input current signal and the applied capacitance. The influence of possible non-ideality and parasitic effects was analysed, in order to reduce their side effects and bring the outcome to acceptable limits through the selection of passive elements. For the verification purposes, a PSPICE simulation environment with CMOS 0.18 μm TSMC technology parameters was selected. An experimental check was performed with off-the-shelf components-IC MAX435, showing satisfactory agreement with theoretical assumptions and conclusions.

Optimal design of CMOS current mode instrumentation amplifier using bio-inspired method for biomedical applications

Analog integrated circuits for biomedical applications require good performance. This paper presents an instrumentation amplifier (IA) design based on three complementary metal oxide semiconductor (CMOS) conveyors with an active resistor. This circuit offers the possibility to control the gain by voltage and current. We have designed the IA to minimize the parasitic resistance (Rx) with large bandwidth and high common mode rejection ratio (CMRR) using the artificial bee colony algorithm (ABC). The topology is simulated using 0.35µm CMOS technology parameters. The optimization problem is represented by an objective function that will be implemented using MATLAB script. The results were approved by the simulation using the advanced design system (ADS) tool. The simulation results were compared to the characteristics of some other instrumentation amplifiers exsisting in the literature. The circuit has a higher CMRR than other topologies.

Water cut forecast after downhole pumping equipment optimization based on displacement characteristics

The article deals with the issue of water cut predicting when downhole pumping equipment optimizing. In practice, an expert assessment of this parameter is used as a rule, which does not take into account the degree of planned optimization relative to the current mode. The paper proposes a methodology allowing taking into account the dynamics of planned fluid withdrawals in predicting water cut based on displacement characteristics. To solve the described problem, four characteristics were selected with a certain type of statistical dependence, where, in one part of the equation, fluid withdrawals do not depend on oil withdrawals. This allows, by setting different values of fluid production, to predict oil production and water cut at any time period. On the example of deposits of one of the regions of the Ural-Volga region, the most suitable for certain geological conditions displacement characteristics were determined. Look back analysis shows a high degree of convergence between the calculated and actual water cut indicators – the average absolute deviation is 1.9%, which allows forecasting with sufficient accuracy. Keywords: oil fields development; production stimulation; displacement characteristics; water cut.

Educating for the future? Mapping the emerging lines of precision education governance

Managing the future has become one of the major focuses of global governance in education. In its current mode, education seems unable to answer the needs and interests of the market and future megatrends, such as globalisation and digitalisation. Calls for precision education to introduce the usage of digital platforms, artificial intelligence in education, and knowledge from the behavioural and life sciences are getting a foothold in widening powerful networks of strengthening global governance and EdTech business. By bringing together some of the emerging changes in education governance, in this article we argue for a new constitution of governance, precision education governance. Precision education governance combines three overlapping and strengthening lines of governance: (i) global governance of education, (ii) marketisation, privatisation and digitalisation, and (iii) behavioural and life sciences as the basis for managing the future education. In the article, we highlight the importance in bringing these so far separately studied lines together to understand how they shape the aims and outcomes of education, knowledge and understanding of human subjectivity more thoroughly than before.