فهرست مطالب

Majlesi Journal of Electrical Engineering - Volume:11 Issue:1, 2017
  • Volume:11 Issue:1, 2017
  • تاریخ انتشار: 1396/01/26
  • تعداد عناوین: 9
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  • Farhad Mesrinejad, Hassan Aliahmadi Page 1
    Recent advances in the field of electronics and wireless telecommunications have created the capability and potential for designing and manufacturing sensors which have low power consumption, small size, reasonable price and various applications. These small sensors, which based on their type, can perform different tasks such as receiving environmental information, processing it and then sending that information, have shaped an idea to create and expand networks known as wireless sensor network (WSN). A sensor network consists of a large number of sensor nodes which are widely distributed in the environment and are engaged in collecting information. The sensors have significant limitations, and one of the most important limitations is the low capacity of these sensors’ battery, which makes the efficient use of the energy a vital issue. When the energy in the battery ends, the sensor’s functions completely stops. This would result in the loss of a part of the network. Moreover, in most of the sensor’s applications, replacing the battery is impossible either because the evaluated area is too large or because it is unsafe. Therefore, minimizing the energy consumption, by designing communication protocols and applications for these networks, is one of the most important issues. So designing a MAC Layer schedule to reduce energy consumption in wireless sensor networks which can significantly reduce power consumption but also would be compatible with IEEE 802.15.4 is an important and unavoidable challenge.
    Keywords: Wireless Sensor Networks, MAC Protocol, Power Consumption, Duty Cycle, Scheduler
  • Urvashi Bansal, Maneesha Gupta, Shireesh Rai Page 9
    Design of a very compact two stage amplifier is proposed by merging passive frequency compensation with a feed forward compensation technique, which achieves significant improvement in gain-bandwidth product (GBW), slew rate and phase margin with lower supply voltage requirement. The mathematical analysis given in this paper justify that the proposed technique offers the advantage of locating poles and zeros at higher frequencies than with the conventional method . The workability of the proposed amplifier has been verified by using Mentor Graphics Eldo simulation tool with TSMC CMOS 0.18 µm process parameters. The simulated results show a GBW of 150 MHz and average slew rate of 98 V/µs with a power consumption of 3.2 mW.
    Keywords: Analog Signal Processing, CMOS, Multistage Amplifier, Passive Compensation, Feed-forward Network
  • Shahrokh Hatefi, Omid Ghahraei, Behzad Bahraminejad Page 19
    A ubiquitous device-widely used in many industrial applications is Computer Numerical Control (CNC) machinery. CNC controller constitutes the main part of a CNC machine, which performs the task of controlling and navigating the tool and implementation of industrial processes. Although there have been many controllers, designed and used, in CNC applications in recent years, most of them experience some limitations and disadvantages towing to the design techniques. This project aims to design and fabricate an innovative Multi Axis Automatic Controller (MAAC) to be used in CNC machinery, which has much superiority over the existing controllers and provides an ideal performance. The MAAC has a closed-loop control system, which can control and drive stepper motors, servo motors, DC motors, and hydraulic and pneumatic movement systems. An Improved accuracy and repeatability within rapid implementation of industrial process could be achieved by using of the MAAC in different CNC applications.
    Keywords: CNC Controller, CNC Machinery, Closed-Loop Linear Control
  • Pankaj Negi, Yash Pal, G. Leena Page 25
    Nowadays the demand for receiving the high quality electrical energy is being increasing as consumer wants not only reliable but also quality power .The usage of automated equipment are increasing and far more susceptible to disturbances compare to the previous generation equipment and information systems. Withthe deregulation of the electric power energy market, the awareness concerning the quality of power has been increasing day by day among different categories of customers. Power quality is an issue that is becoming increasingly important to electricity consumers at all levels of usage. Power quality can be improved in distributed system by using shunt compensation device known as DistributionStatic Compensator (DSTATCOM). This paper covers the different topologies of Distribution Static Compensators (DSTATCOMs) and the various control methodologies, and its selection for specific applications.Nowadays the demand for receiving the high qualityelectrical energy is being increasing as consumer wants not onlyreliable but also quality power .The usage of automated equipmentare increasing and far more susceptible to disturbances compare tothe previous generation equipment and information systems. Withthe deregulation of the electric power energy market, the awarenessconcerning the quality of power has been increasing day by dayamong different categories of customers. Power quality is an issuethat is becoming increasingly important to electricity consumers atall levels of usage. Power quality can be improved in distributedsystem by using shunt compensation device known as DistributionStatic Compensator (DSTATCOM). This paper covers the differenttopologies of Distribution Static Compensators (DSTATCOMs) andthe various control methodologies, and its selection for specificapplications.
    Keywords: Index Terms, Distribution Static Compensator (DSTATCOM), Power Quality, Custom Power
  • Akbar Karimi Pouya Page 37
    The purpose of this paper is to design an adaptive neuro-fuzzy controller to control the speed of the BLDC motor. This paper throws overall view of the performance of fuzzy PID controller and compares with fuzzy - adaptive neural controller. Take characteristics of suitable in PID controller is difficult. But fuzzy is the ability to take appropriate control parameters and calculations easier. An adaptive neuro fuzzy control system has the advantages of both types of fuzzy control system and neuro system. Paper examines the BLDC motor speed control based on adaptive neuro - fuzzy First tried to have a simulated fuzzy PID controller And then designing controller adaptive neuro - fuzzy using ANFIS toolbox for the motor. And we compare the characteristics of speed, torque, current and voltage in the three controllers finally, we conclude that the characteristic of the controller adaptive neuro - fuzzy (ANFIS) is better than the other two controllers.
    Keywords: BLDCM, Fuzzy PID Controller, ANFIS
  • Amin Zafarian, Iraj Kalali Fard, Abbas Golmakani, Jalil Shirazi Page 45
    In this paper a low-noise amplifier with 0.6 V supply voltage, low power consumption, and improved linearity at= 5 GHz is introduced in 0.18 µm CMOS technology. By using a feed-forward structure and a multi-gated configuration in the proposed circuit, linearity of the circuit is significantly improved, while only 122 µW more power is consumed compared to conventional folded cascode structure, and the other circuit parameters are similar. In addition, the Volterra series is used for nonlinear analysis and to evaluate the linearity improvement of the proposed circuit. There is also a noteworthy superiority over compared published works in the figure of merit. The suggested low-noise amplifier (LNA) at 1.28 mW DC power consumption provides 9.6 dB gain and a noise figure of 3.24 dB. It is achieved whilst the third order interception point has been improved by 10 dB and equals 0.0 dBm. In the operating frequency the circuit displays satisfactory input and output impedance matching. Finally, throughout the whole circuit bandwidth input and output isolation is below −27 dB.
    Keywords: DSTATCOM, Power Quality, Fuzzy Controller
  • Ali Darvish Falehi, Mansour Rafiee Page 53
    From the viewpoint of technology-driven custom apparatus, the dynamic voltage restorer (DVR) has been identified to be the most prominent device which can be engaged to compensate the voltage sag. On the other hand, this device has been customarily used in power distribution system to protect sensitive loads from sudden voltage sag. Owing to the restriction of energy storage in DVR's capacitors, it is essential that the active power injection by DVR to be reduced. As a consequence, this energy-saving strategy leads to the injecting the larger voltage magnitude and reactive power, shifting the phase, and cluttering the voltage wave shape. In the interim, this strategy is highly sensitive respect to variation in load’s power factor so that the compensating operation will not be properly done. In this regard, this paper suggests a robust controller based on minimum active power strategy in order to perfectly correct the voltage sag notwithstanding variation in load’s power factor. Likewise, the under-study DVR has been structured according to the cascaded H-bridge multilevel inverter topology.
    Keywords: H-bridge Multilevel Inverter, Voltage Sag, DVR, Minimum Active Power Strategy, Load Power Factor
  • Ali Nehbandan Dokht, Mahmoud Ghasemi, Abbas Golmakani Page 61
    Current starved delay elements (CSDEs) are among the popular architectures to manipulate rising or falling edges of signals in order to meet timing requirements. The digitally controllable generations of these topologies are now monotonic and reasonably power efficient, but they lack linearity in full range. Inherently, this subject may not seem problematic because by setting the dimensions of the design elements the desired delay can be acquired. However, in case that a chain of incremental delays are required we tend to employ more linear designs. In this paper two improvements in linearity are examined for two known CS designs. Both of the topologies are in 0.18um technology and meet appropriate design parameters like power, area and monotonic response.
    Keywords: Current starved, Delay element, Linearity, Monotonic, Power, Process, Temperature
  • Marjan Bahadori, Seyed Saeed Allah Mortazavi, Mahmood Joorabian, Arash Rohani Page 71
    In this paper, a new fuzzy controller for a three-phase and three-wire distribution static compensator (DSTATCOM) is presented to improve power quality. A three-leg voltage source converter based DSTATCOM is used to control the harmonic currents for two nonlinear loads. In this control system, the gate pulses for IGBT switches are provided by a hysteresis controller, using samples of source voltages and currents. The derived reference currents, obtained by the direct method of reference current estimation with two PI and Fuzzy control models are simulated in a MATLAB/ Simulink environment and each performance is analyzed. Comparisons show that the fuzzy controller performs better than a classic PI controller
    Keywords: Low Noise Amplifier (LNA), Folded Cascode Structure, Low Power Consumption, Low Supply Voltage, Improved Linearity