จำนวน Repository ( 18 )

การตรวจจับกระแสฮาร์มอนิกสําหรับตัวกรองฮาร์มอนิกแบบแอคทีพชนิดปรับ ค่าได้เอง โดยใช้ขั้นตอนวิธีแบบ RLS
การตรวจจับกระแสฮาร์มอนิกสําหรับตัวกรองฮาร์มอนิกแบบแอคทีพชนิดปรับ ค่าได้เอง โดยใช้ขั้นตอนวิธีแบบ RLS

This thesis proposes a method for detecting harmonics current in the adaptive active harmonic filter with Recursive Least Square (RLS) algorithm. The proposed method is based on the theory of noise cancellation adaptive filter. Originally the theory was used for audio signal processing but this thesis is applied to the harmonic current detector of an active harmonic filter. The principle and construction of the harmonic current detector in the adaptive active harmonic current filter with Least Mean Square (LMS) algorithm and Recursive Least Square (RLS) algorithm are presented to compare the efficiency of both algorithms. Then simulate these two algorithms with Matlab-Simulink program to simulate the three case studies. All three case studies that simulate are generally available in industrial plants. The simulation results show that the harmonic current detector in the adaptive active harmonic current filter with the LMS algorithm and the RLS algorithm can detect the harmonic currents in the power systems. However the RLS algorithm is more efficient and has less error value than the LMS algorithm. Therefore it is confirmed that the RLS algorithm proposed in this thesis is appropriate to use with the adaptive active harmonic current filter to really work in the industry.

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Comparison of PWM power rectifier between 6 pules and 12 pules converter topology
Comparison of PWM power rectifier between 6 pules and 12 pules converter topology

This paper presents a study of comparison of PWM power rectifier between 6 Pules and 12 Pules converter topology by small hydro turbine Generator (20kW) is power supply and Compare harmonics Current feed in the systems. Both converter connected Permanent Magnet Synchronous Generator (PMSG) and Voltage Regulator Control at 700 V. The control system by Decoupling Control and Conventional PI Control for control parameter PI value by Nicole-Ziegler method. Analysis for Performance of the system presented a mathematical model with Matlab/Simulink program. The result of simulation have value less than 5 percent of ripple voltage and Voltage Control continuously. Converter 12 pulse have harmonics Current value feed in the systems less than converter 6 pulse. This Case study can apply using PWM power rectifier control in future work

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Design of cmos voltage reference circuit
Design of cmos voltage reference circuit

This paper presents a CMOS voltage reference design which is widely used in electronic circuits both analog and digital circuits. In the conventional a CMOS voltage reference circuit design composed of several MOS transistors and complicated circuits the output voltage cannot be adjusted to any levels. Therefore in this paper proposed the CMOS voltage reference circuit design technique based on a new current combination circuit which it was reduced number of MOS transistors and the proposed circuit is able to operate without complex startup circuit. The performance of the proposed circuit is confirmed through PSPICE simulation results the circuit can be operated with supply voltage varies from 2V to 4V the output voltage reference is about 231 2mV at wide temperature range of -80 to 120 it has very low temperature coefficient of about 37.65 ppm/ and a total power dissipation of 7.37 W

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A fully-balanced current-tunable phase-lead all-pass filter
A fully-balanced current-tunable phase-lead all-pass filter

A new integrable fully-balanced current-tunable in phase-lead all-pass filter is presented. The architecture of the circuit is relatively simple and symmetry with differential signals consisting of merely 6 NPN Bipolar transistors. Without external resistors and matching condition the proposed circuit is very appropriate to further develop into an integrated circuit. Simulation results shown that: frequency is a function of bias current- the increasing currents effect the higher frequency frequency is a function of capacitance low-power-consumption and the maximum useful frequency of 250 MHz

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Design of the control system to control AC/DC converter with a fast transient response
Design of the control system to control AC/DC converter with a fast transient response

This paper presents a design of the control system to control AC/DC converter. Algorithm of a control system design consists of the output voltage loop control used a fuzzy gain scheduling of PI control and the current loop control used a hysteresis control which is described in this paper. The evaluation of the proposed control system is used to control an isolated CUK AC/DC converter operation with a 250W load and a -48V output voltage. The system is achieved as the following; the tight output voltage both the steady state operation and the transient response a power factor is nearly unity and the waveform of input current is nearly sinusoidal. In addition the control system design is simple and uncomplicated

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