Comparative Study of PI, Fuzzy and Fuzzy tuned PI Controllers for Single-Phase AC-DC Three-Level Converter

Gnanavadivel J,Senthil Kumar N,Yogalakshmi P 대한전기학회 2017 Journal of Electrical Engineering & Technology Vol.12 No.1

This paper presents the design of closed loop controllers operating a single-phase AC-DC three-level converter for improving power quality at AC mains. Closed loop inhibits outer voltage controller and inner current controller. Simulations of three level converter with three different voltage and current controller combinations such as PI-Hysteresis, Fuzzy-Hysteresis and Fuzzy tuned PI-ysteresis are carried out in MATLAB/Simulink. Performance parameters such as input power factor and source current total harmonic distortion (THD) are considered for comparison of the three controller combinations. The fuzzy-tuned PI voltage controller with hysteresis current controller combination provides a better result, with a source-current THD of 0.93% and unity power factor without any source side filter for the three level converter. For load variations of 25% to 100%, a THD of less than 5% is obtained with a maximum value of only 1.67%. Finally, the fuzzy-tuned PI voltage with hysteresis controller combination is implemented in a Xilinx Spartan-6 XC6SLX25 FPGA board for experimental validation of power quality enhancement. A prototype 100 W, 0-24-48 V as output converter is considered for the testing of controller performance. A source-current THD of 1.351% is obtained in the experimental study with a power factor near unity. For load variations of 25% to 100%, the THD is found to be less than 5%, with a maximum value of only 2.698% in the experimental setup which matches with the simulation results.

SVM 기반 히스테리시스 제어기를 이용한 D-STATCOM 전류 제어에 관한 연구

유지윤,최정혜,신은철 전력전자학회 2006 전력전자학회 논문지 Vol.11 No.4

This paper proposes a control algorithm for STATic synchronous COMpensator(STATCOM), based on Space Vector Modulation(SVM) and Hysteresis Current Controller(HCC) techniques. STATCOM is used to reactive power compensation on a distribution network. The proposed algorithm utilizes the advantages of the fast dynamic response of the hysteresis current control and the reduced switching number of the SVM scheme. The controller determines a set of space vectors from a region detector and applies a space vector. A set of space vectors including the zero vector, to reduce the number of switching, is determined from output signals of two hysteresis comparators. The presented control system was tested with digital simulation in the Borland C++ program and demonstrate the advantage of the proposed hysteresis current controller. 배전급 STATCOM(Distribution-network STATic synchronous COMpensator)에 적용 가능한 공간 벡터 변조(Space Vector Modulation, SVM) 기법을 이용한 히스테리시스 전류제어기를 제안하였다. 히스테리시스 전류제어기는 빠른 응답 특성, 쉬운 구현, 파라미터 변화에 대한 둔감성 등 많은 장점에도 불구하고 높은 스위칭 주파수와 제한되지 않는 전류 오차 때문에 스위칭 주파수에 영향을 받는 배전급 STATCOM 전류제어기로는 적합하지 않았다. 또한 전압 벡터의 인가방식에서도 뚜렷한 근거가 없어 전류오차가 제한되지 않았다. 이에 본 논문에서는 구역판별기, SVM, 그리고 외부와 내부 히스테리시스 제어기를 이용하여 높은 스위칭 주파수를 저감하고 특정 밴드 내에서 전류 오차를 줄인 개선된 SVM 기반의 히스테리시스 전류제어기를 제안하고 모의실험을 통해 제안한 기법의 유효성을 입증하였다.

Current Controlled PWM for Multilevel Voltage-Source Inverters with Variable and Constant Switching Frequency Regulation Techniques

S. P. Gawande,M. R. Ramteke 전력전자학회 2014 JOURNAL OF POWER ELECTRONICS Vol.14 No.2

Due to advancements in power electronics and inverter topologies, the current controlled multilevel voltage-source pulse width modulated (PWM) inverter is usually preferred for accurate control, quick response and high dynamic performance. A multilevel topology approach is found to be best suited for overcoming many problems arising from the use of high power converters. This paper presents a comprehensive review and comparative study of several current control (CC) techniques for multilevel inverters with a special emphasis on various approaches of the hysteresis current controller. Since the hysteresis CC technique poses a problem of variable switching frequency, a ramp-comparator controller and a predictive controller to attain constant switching frequency are described along with its quantitative comparison. Furthermore, various methods have been reviewed to achieve hysteresis current control PWM with constant switching frequency operation. This paper complies various guidelines to choose a particular method suitable for application at a given power level, switching frequency and dynamic response.

Current Controlled PWM for Multilevel Voltage-Source Inverters with Variable and Constant Switching Frequency Regulation Techniques: A Review

Gawande, S.P.,Ramteke, M.R. The Korean Institute of Power Electronics 2014 JOURNAL OF POWER ELECTRONICS Vol.14 No.2

Due to advancements in power electronics and inverter topologies, the current controlled multilevel voltage-source pulse width modulated (PWM) inverter is usually preferred for accurate control, quick response and high dynamic performance. A multilevel topology approach is found to be best suited for overcoming many problems arising from the use of high power converters. This paper presents a comprehensive review and comparative study of several current control (CC) techniques for multilevel inverters with a special emphasis on various approaches of the hysteresis current controller. Since the hysteresis CC technique poses a problem of variable switching frequency, a ramp-comparator controller and a predictive controller to attain constant switching frequency are described along with its quantitative comparison. Furthermore, various methods have been reviewed to achieve hysteresis current control PWM with constant switching frequency operation. This paper complies various guidelines to choose a particular method suitable for application at a given power level, switching frequency and dynamic response.

A Hysteresis Current Controller for PV-Wind Hybrid Source Fed STATCOM System Using Cascaded Multilevel Inverters

R. Palanisamy,K. Vijayakumar 대한전기학회 2018 Journal of Electrical Engineering & Technology Vol.13 No.1

This paper elucidates a hysteresis current controller for enhancing the performance of static synchronous compensator (STATCOM) using cascaded H-bridge multilevel inverter. Due to the rising power demand and growing conventional generation costs a new alternative in renewable energy source is gaining popularity and recognition. A five level single phase cascaded multilevel inverter with two separated dc sources, which is energized by photovoltaic - wind hybrid energy source. The voltages across the each dc source is balanced and standardized by the proposed hysteresis current controller. The performance of STATCOM is analyzed by connecting with grid connected system, under the steady state & dynamic state. To reduce the Total Harmonic Distortion (THD) and to improve the output voltage, closed loop hysteresis current control is achieved using PLL and PI controller. The performance of the proposed system is scrutinized through various simulation results using matlab/simulink and hardware results are also verified with simulation results.

스위치드 릴럭턴스 전동기의 히스테리시스 및 PI 전류제어기 응답특성

김동희,백원식,김민회,Kim, Dong-Hee,Baik, Won-Sik,Kim, Min-Huei 한국조명전기설비학회 2007 조명·전기설비학회논문지 Vol.21 No.5

This paper presents a comparison of different current controller response characteristics of SRM. The most common current controllers of the SRM is hysteresis type. The hysteresis controller is easy to implement and fast current control response, but has the inherent disadvantage of switching frequency variations. The other common type of current controller is PI scheme. The design of a classical PI current controller with fixed parameters for SRM is not an easy task due to the extreme nonlinear characteristics. In this paper, some linearization technique is used for design of PI current controller. Experimental results of 1-hp SRM are presented for the basic reference data which can be used to select the proper current control scheme according to the applications. 본 논문에서는 스위치드 릴럭턴스 전동기 (SRM)의 히스테리시스 및 PI 전류제어기법의 응답특성에 관해 고찰하였다. SRM의 전류제어를 위해 가장 널리 적용되는 히스테리시스 제어기법은 전류응답특성이 빠르다는 장점이 있으나, 스위칭 주파수의 가변으로 인한 소음이 단점으로 알려져 있다. SRM의 전류제어를 위해 적용되는 다른 전류 제어기법으로는 PI 전류제어기법이 있으나, 비선형적인 특성으로 인해 일반적인 전동기 제어시스템과 같이 몇몇 고정된 변수들로 제어기를 설계하기가 용이하지 않다. 본 논문에서는 제한된 범위 내에서 전동기가 구동된다는 가정하에 선형화를 통한 PI 전류제어기를 설계하였다. 1마력 SRM을 적용하여 전류제어 및 속도제어 실험을 수행하였으며, 실험을 통해 얻어진 데이터는 적용 용도에 적합한 전류제어기법 선정을 위한 참고자료가 될 것으로 사료된다.

Investigation on Operating Characteristics in Three Level Full Bridge AC–DC Converter using Diferent Control Strategies for Telecom

K. R. Shanmuga Vadivu,R. Ramaprabha 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.3

This paper presents the improvement of operating characteristics of three level full bridge ac–dc converter by proposing four diferent closed loop control techniques for telecom applications. Comparisons between diferent controllers have been considered to evaluate the power quality parameters with fast dynamic response under various operating conditions. Simulations have been done with Matlab/Simulink with four diferent voltage and current controllers, namely; PID with hysteresis current controller, Fuzzy Logic with hysteresis current controller (FL-HCC), Hysteresis Modulation based Sliding Mode Controller (HM-SMC) and Genetic Algorithm based Average Current Control (GA-ACC). Comparative analysis has been carried out with power factor, total harmonic distortion (THD) for various loading conditions upto 300 W. Based on the comparative analysis, GA-ACC technique provides better power quality parameters with improved dynamic response than the other three controllers. GA-ACC technique improved the power factor to 0.9911 and source current THD of 5.11% for converter. Also, voltage ripple and efciency of the converter were calculated and tabulated under a wide range of load variations. Simulated results of the converter with GA-ACC have been validated with the experimental results.

A Shunt Active Filter for Reactive Power Compensation and Harmonic Mitigation

Narayan G. Apte,Vishram N. Bapat,Amruta N. Jog 전력전자학회 2007 ICPE(ISPE)논문집 Vol.- No.-

This paper presents a digital simulation of a 3Φ Shunt Active Filter (SAF) for harmonic and reactive power compensation. The instantaneous harmonic and reactive compensating currents is desegregated in it’s three components viz., (a) fundamental reactive current (b) oscillating harmonic reactive current (c) oscillating harmonic active current. The resultant compensating current is injected to the point of common coupling (PCC) of the ac mains by a six pulse, hysteresis current controlled, Voltage Source Inverter (VSI). A high performance hysteresis band modulation technique is proposed to maintain nearly constant device switching frequency. The hysteresis bandwidth is modulated as a function of the desired switching frequency , supply voltage, DC bus voltage and slope of the reference current. Responses of simulated model clearly reveal the desired performance of SAF.

Fuzzy 제어기를 이용한 7상 BLDC 전동기 속도제어 구동시스템

윤용호(Yong-Ho Yoon) 대한전기학회 2017 전기학회논문지 Vol.66 No.11

A BLDC motor with higher number of phases has several advantages, compared to the conventional three-phase BLDC motors. It can reduce the commutation torque ripple and the iron loss without increasing the voltage per phase and increase the reliability and power density. Higher number of phases increase the torque-per-ampere ratio for the same machine volume and output power by widening the electrical conduction period. In this paper, the proposed seven-phase BLDC motor drive system is made into several functional modular blocks, so that it can be easily extended to other ac motor applications: back-EMF block, hysteresis current control block, pwm inverter block, phase current block, and speed/torque control block. Also in a system of BLDC motor drive, the PI controller has been widely used in the speed controller because of the simple implementation. To obtain a good speed response in a general drive system using the PI controller, the high bandwidth of a controller is established. therefore, in this paper, a Fuzzy controller is applied to the 7-phase BLDC motor drive system in order to improve the speed control performance. The Fuzzy controller is compared with a conventional PI controller through the experiment with respect to speed dynamic responses. These experimental results show that the Fuzzy controller of the 7-phase BLDC motor drive system is superior over the conventional PI controller. The algorithm using the Fuzzy controller can improve a comfortable ride in the field of high performance 7-phase BLDC motor drive applications.

Quasi-Fixed-Frequency Hysteresis Current Tracking Control Strategy for Modular Multilevel Converters

Mei, Jun,Ji, Yu,Du, Xiaozhou,Ma, Tian,Huang, Can,Hu, Qinran The Korean Institute of Power Electronics 2014 JOURNAL OF POWER ELECTRONICS Vol.14 No.6

This study proposes a quasi-fixed-frequency hysteresis current tracking control strategy for modular multilevel converters (MMCs) on the basis of voltage partition principle. First, by monitoring the grid voltage and the deviation between the output and reference currents, the output voltage is determined, thus prompting the output current to quickly and efficiently track the given current. Second, the voltages of the upper/lower capacitor of the arm and the voltages between the upper and lower arms are balanced by combining these arms with virtual loop mapping and arm voltage balance control, respectively. In particular, the proposed method is designed for any level and number of sub-modules. The validity of the proposed method is verified by simulations and experimental results of a five-level MMC prototype.