Recent Advances in Electrical & Electronic Engineering - Volume 12, Issue 6, 2019

Background: The solar field on our planet is inexhaustible, which favors the use of photovoltaic electricity which generates no nuisance: no greenhouse gases, no waste. Methods: It is a high value-added energy that is produced directly at the place of consumption through photovoltaic (PV) solar panels. Notwithstanding these advantages, the maximum power depends strongly on solar irradiation and temperature, which means that a Maximum Power Point Tracking (MPPT) controller must be inserted between the PV panel and the load in order to follow the Maximum Power Point (MPP) continuously and in real time. In this work, MPP’s behavior was simulated at different temperatures and solar irradiations using seven techniques which identify the MPP by different methods. Results: The novelty of this work is that the seven MPPT methods were compared according to a very selective criterion which is the MPPT efficiency as well as a purely digital duty cycle control without using the PI controller. The simulation under the PSIM software shows that the FLC, TP, FSCC, TG, HC and IC methods have almost the same efficiency of 99%, whereas the FOCV method had a low efficiency of 96%. Conclusion: This makes it possible to conclude that the best methods are FLC, HC and IC because they use fewer sensors compared to the rest.

Ultrasound imaging is one of the non-invasive imaging, that diagnoses the disease inside a human body and there are numerous ultrasonic devices being used frequently. Entropy as a well known statistical measure of uncertainty has a considerable impact on the medical images. A procedure for minimizing the entropy with respect to the region of interest is demonstrated. This new approach has shown the experiments using Extracted Region Of Interest Based Sharpened image, called as (EROIS) image based on Minimax entropy principle and various filters. In this turn, the approach also validates the versatility of the entropy concept. Experiments have been performed practically on the real-time ultrasound images collected from ultrasound centers and have shown a significant performance. The present approach has been validated with showing results over ultrasound images of the Human Gallbladder.

Background: Electromagnetic detection is an important method of geophysical exploration. The transmitting system is an important part of the electromagnetic detection equipment. Methods: The general topologies of a transmitting system for EM instrument are analyzed. The basic principle of EM detection is interpreted. In order to improve the output power and give consideration to the dynamic performance, an electromagnetic transmitting system based on the tri-state boost converter is proposed in this paper. Results: The principle of the proposed transmitting system is analyzed. The topology of the proposed transmitting system is illustrated and the working modes of tri-state boost converter are given. Conclusion: The simulation model is established and the simulation experiment is carried out to verify the feasibility of the new electromagnetic transmitting system.

Objective: A tunable CMOS active inductor/resonator based Voltage Controlled Oscillator (VCO) has been presented. In the design of LC-VCO, LC resonator (tank) circuit has been substituted with gyrator based CMOS active inductor/resonator. The purity of VCO output signal is defined by the phase noise parameter. Methods: For good spectral purity of VCO output signal, the phase noise should be minimum. Moreover, the quality factor of LC resonator is inversely proportional to the phase noise of VCO output signal. In the presented work, a high-quality active inductor/resonator circuit has been used to design VCO which minimizes the phase noise and chip area as well. Further, other VCO characterization factors are measured. Results: The designed circuit has been implemented in 0.18μm CMOS technology. Conclusion: The design of the proposed AI based voltage controlled oscillator shows better phase noise, less chip area and high output power. The high output power is achieved at the cost of limited tuning range of 1.14 GHz ~ 2.1 GHz. The presented active inductor based voltage controlled oscillator can be used for RF applications from 1.14GHz ~ 2.1GHz.

Background: This paper presents a low noise and low distortion telescopic Operational Trans-conductance Amplifier (OTA) that is suited to biomedical signal processing. In our proposal, source degeneration using CMOS transmission gate is introduced in telescopic OTA to realize current- voltage negative feedback. The negative feedback degenerates Gm, reduces flicker noise and reduces distortion. Methods: The circuit is simulated by using TSMC 90nm CMOS process technology with 1.8V supply voltage. We obtained promising simulation results that show THD less than -90dB and flicker noise 60 nV at 4kHz corner frequency. Results: The frequency response plot reveals that our circuit offers a voltage gain of 63dB with negative feedback and achieves a phase margin of about 70 degrees. Thus, this topology is a feasible solution for low noise and low distortion biomedical signal amplifier circuits. Conclusion: A highly linear and low noise telescopic OTA topology was proposed in this paper. A simple but efficient technique of source degeneration is used with negative feedback to achieve low distortion and low noise.

Background: Middleware has been widely adopted as an efficient approach to facilitate the development process of large-scale distributed systems. Although this approach can achieve simplified system design and reduced time consumption, it has a strong demand for real-time task processing and data transmitting. Traditional middleware, which lacks the real-time performance guarantee mechanism, cannot be adopted by the distributed systems with strict time restrictions. Methods: In order to meet the real-time requirements of distributed systems, the functional requirements of middleware are studied, and a real-time publish/subscribe middleware is designed and implemented in this paper. A hierarchical design is adopted to build this middleware from a model layer, a communication layer and a support layer. The middleware has the data synchronization on distributed objects, Ethernet-based publish/subscribe mechanism and the real-time performance guarantee mechanism. Results: Experiments show that the proposed middleware satisfies the needs of distributed applications, and ensures that the end-to-end data communication delay is less than 1 millisecond, which meets the real-time requirements of data transmission in distributed systems. Conclusion: In this paper, we design and implement a real-time middleware based on the publish/ subscribe mechanism.

Background: Due to the increasing demand for the electrical power and limitations of conventional energy to produce electricity. Methods: Now the Microgrid (MG) system based on alternative energy sources are used to provide electrical energy to fulfill the increasing demand. The power system frequency deviates from its nominal value when the generation differs the load demand. The paper presents, Load Frequency Control (LFC) of a hybrid power structure consisting of a reheat turbine thermal unit, hydropower generation unit and Distributed Generation (DG) resources. Results: The execution of the proposed fractional order Fuzzy proportional-integral-derivative (FO Fuzzy PID) controller is explored by comparing the results with different types of controllers such as PID, fractional order PID (FOPID) and Fuzzy PID controllers. The controller parameters are optimized with a novel application of Grasshopper Optimization Algorithm (GOA). The robustness of the proposed FO Fuzzy PID controller towards different loading, Step Load Perturbations (SLP) and random step change of wind power is tested. Further, the study is extended to an AC microgrid integrated three region thermal power systems. Conclusion: The performed time domain simulations results demonstrate the effectiveness of the proposed FO Fuzzy PID controller and show that it has better performance than that of PID, FOPID and Fuzzy PID controllers. The suggested approach is reached out to the more practical multi-region power system. Thus, the worthiness and adequacy of the proposed technique are verified effectively.

Background: Automatic Generation Control (AGC) of multi-area nonlinear power system integrated with wind energy based Renewable Energy Conversion System (RECS). Methods: A fuzzy PID controller has been proposed for AGC of a three equal area thermal system integrated with RECS. Different physical nonlinear constraints like Governor Dead Band (GDB) and boiler dynamics are introduced in the model for realization of non linear and realistic of proposed multi area power system. To determine the optimum gain parameter, a Modified Symbiotic Organism Search (M-SOS) algorithm has been used along with a fitness function which based on Integral of Time Multiplied Absolute Error (ITAE). Results: For performance analysis, the performance of proposed M-SOS optimized fuzzy-PID controller is compared with PI, PID and fuzzy PI controllers. For technique comparison, performance of proposed M-SOS technique is compared with original SOS and conventional PSO algorithms. Robustness of proposed controller has also been verified by varying applied load and system parameters. Conclusion: It is observed that M-SOS technique exhibits improved performance over original SOS and PSO algorithms. It is also observed that proposed Fuzzy-PID controller provides better system performance than PI, PID and fuzzy PI controllers. It has been observed that the proposed M-SOS tuned fuzzy PID controller improves settling time of frequency response in area 1 by 11.30%, 15% and 17.75% compared to M-SOS tuned fuzzy PI, PID and PI controllers respectively. Significant improvements in settling time, peak overshoot and peak undershoot of the frequency response in area 2 and tie line power are observed with the implementation this proposed approach.

Background: This study first efficiently applies the previous result Chen Electrical Unifying Approach (CEUA) utilized in the basic circuit theory to construct the control system matrix equation of the complicated block diagram. Methods: Based on the simple matrix operations proposed in this study, we can easily derive the transfer function without using the traditional Mason rule and the reduced techniques of the block diagram. We have successfully proposed a unifying approach to improve the disadvantages of the Mason rule, in which all loops must be found out and only the transfer function between the input node and the output node is evaluated, and the shortcoming of the reduced techniques for the block diagram is that the calculating process is too complex to be accepted. Results: The salient features of the proposed method are that the transfer function of the complicated block diagram can be easily obtained without using traditional Mason rule and the transfer function of any two nodes is immediately derived within only one calculation. Conclusion: We compared some demonstrated examples with some traditional approaches. Moreover, to demonstrate the practical applicability, the study has investigated one practical example.

Background: A smart monitoring system is essential to improve the quality of pig farming. A real-time monitoring system provides growth, health and food information of pigs while the manual monitoring method is inefficient and produces stress on pigs, and the direct contact between human and pig body increases diseases. Methods: In this paper, an ARM-based embedded platform and image recognition algorithms are proposed to monitor the abnormality of pigs. The proposed approach provides complete information on in-house pigs throughout the day such as eating, drinking, and excretion behaviors. The system records in detail each pig's time to eat and drink, and the amount of food and water intake. Results: The experimental results show that the accuracy of the proposed method is about 85%, and the effect of the technique has a significant advantage over traditional behavior detection methods. Conclusion: Therefore, the ARM-based behavior recognition algorithm has certain reference significance for the fine group aquaculture industry. The proposed approach can be used for a central monitoring system.