• Journal of Electrical Engineering and Technology
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• 제13권1호
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• pp.270-279
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• 2018

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.

• Journal of Electrical Engineering and Technology
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• 제10권2호
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• pp.529-538
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• 2015

Due to the high efficiency and compact mechanical structure, direct drive variable speed generators are used for power conversion in wind turbines. The wind energy conversion system (WECS) considered in this paper consists of a permanent magnet synchronous generator (PMSG), uncontrolled rectifier, dc-dc boost converter controlled with maximum power point tracking (MPPT) and adaptive hysteresis controlled voltage source inverter (VSI). For high utilization of the converter's power capability and stabilizing voltage and power flow, constant DC-link voltage is essential. Step and search MPPT algorithm which senses the rectified voltage ($V_{DC}$) alone and controls the same is used to effectively maximize the output power. The adaptive hysteresis band current control is characterized by fast dynamic response and constant switching frequency. With MPPT and adaptive hysteresis band current control in VSI, the DC link voltage is maintained constant under variable wind speeds and transient grid currents respectively.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 B
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• pp.1208-1210
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• 2003

Most of all, DTC drive is very simple in its implementation because it needs only two hysteresis comparator and switching vector table for both flux and torque control. The amplitude of hysteresis band greatly influences on the drive performance such as flux and torque ripple and inverter switching frequency. In this paper the influence of the amplitudes of flux and torque hysteresis bands and sampling time of control program on the torque and flux ripples are investigated. Simulation results confirm the superiority of the DTC under the proposed method over the conventional DTC.

• 한국소음진동공학회논문집
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• 제15권7호
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• pp.878-884
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• 2005

This paper presents an algorithm for the precision motion control based on the dynamic characteristics of piezoelectric actuators in the inchworm. The dynamic characteristics are identified by the frequency domain modeling technique using the experimental data. For the motion control, the hysteresis behavior is compensated by the inverse hysteresis model. The dynamic stiffness of an inchworm is generally low compared to its driving condition, so mechanical vibration may degenerate the motion accuracy of the inchworm. The Sliding mode controller and the Kalman filter are designed for motion control of the inch-worm.

• Journal of Power Electronics
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• 제17권6호
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• pp.1563-1576
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• 2017

This paper presents a novel switching pattern current control (SP-CC) scheme, which is applied in three-phase voltage-source converters (VSCs). This scheme can select the optimal output switching pattern (SP) by referring the basic principle of space vector modulation (SVM). Moreover, SP-CC is a method without a carrier wave. Thus, the implementation process is concise and easy. When compared with the conventional hysteresis current control (C-HCC) and the space vector-based hysteresis current control (SV-HCC), the SP-CC has the performances of faster dynamic response of C-HCC and less switching number (SN) of SV-HCC. In addition, it has less harmonic contents in the three-phase current, along with a lower switching loss and a higher efficiency. Moreover, the hysteresis bandwidth and Clarke conversion are not required in the SP-CC. The effectiveness of the presented SP-CC is verified by simulation and experimental test results. In addition, the advantages of the SP-CC, when compared with the C-HCC and SV-HCC, are verified as well.

• 한국통신학회논문지
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• 제30권7B호
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• pp.440-449
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• 2005

본 논문에서는 위성통신 링크를 이용한 DAMA방식 호 서비스를 할 때 일부 제어채널의 고장으로 인한 과부하 발생시 이에 대한 측정 방안과 관리 기법을 제안하고 그 성능을 분석한다. 제안하는 기법은 망제어기에서 호 접속제어를 위한 Access 채널의 부하를 측정하여 과부하 상태를 검출하고 이를 DAMA망의 단말들에 고지하여 과부하제어를 수행함으로써 부하 상태에서 시스템의 성능과 안정성을 향상시킨다. 또한, 너무 잦은 과부하 상태 변경이 이루어지지 않도록 상태변경을 함에 있어 Hysteresis 특성을 반영하였다. 분석결과 과부하로 인한 호설정 지연의 과도한 증가 및 호성공율의 급격한 저하를 방지할 수 있으며, 잦은 상태 변경을 방지함으로써 망의 안정성을 높여줌을 알 수 있었다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 추계학술대회 논문집
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• pp.41-45
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• 2001

This paper presents an implementation of motion control system of Switched Reluctance Motor (SRM) using digital hysteresis controller by TMS320F240 DSP. SRM position control system possess several advantages over other motors, including high efficiency, simple structure, low cost, and four-quadrant operation at a wide speed range, especially for the servo drive systems with precision, stability and fast response characteristics in the industrial applications. In the suggested motion control system, position control using digital hysteresis controller is developed, and is evaluated using experimental testing. The developed system for cost reduction and high-performance by fully digital controller is shown a good response characteristic of motion control results.

• Journal of Power Electronics
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• 제14권6호
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• pp.1263-1271
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• 2014

A novel hysteresis PWM control strategy for synchronous buck converter is proposed. The proposed control strategy is based on ampere-second balance of the modulate capacitor, which not only offers faster transient response to meet the challenges of the power supply requirements of fast dynamic load changes, but also provides better stability and solves the compensation problem of error amplifier in the conversional voltage PWM control. Finally, the steady-state and dynamic operation of the control method is analyzed and verified by simulation and experimental results.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 A
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• pp.525-527
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• 1996

Hysteresis current control is one of the simplest techniques used to control currents for high speed drive systems, because of its simplicity of implementation, fast current control response, and inherent peak current limiting capability. However the conventional fixed-band hysteresis control has a variable switching frequency throughout the fundamental period, and consequently the load current harmonics spreaded on the wide frequency range. In this paper, a simple, novel alterative approach is proposed for a variable-hysteresis band current controller which uses feedback techniques to achieve constant switching frequency with good dynamic response. The method is easily implemented in hardware, the resultant controller is easily tuned to a particular load, and has good immunity to variation in PV parameter and dc supply voltage.

• 조명전기설비학회논문지
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• 제23권1호
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• pp.150-155
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• 2009

히스테리시스 전류 제어방식은 원리와 구조가 간단하여 널리 사용되었으나, 전류 오차 허용 밴드폭이 너무 작거나, 전원 전압이 상대적으로 너무 큰 경우 등에는 스위칭 주파수가 급격히 증가하여 많은 열을 발생할 수 있는 등의 단점이 있었다. 이에 본 연구에서는 단상 전류제어에서 0 모드를 추가하고, 기준 전류의 기울기를 비교하여 히스테리시스 전류 제어를 수행함으로써 대폭적인 스위칭 주파수 감소와 안정적인 전류제어가 가능하게 하였다. 또한 이를 컴퓨터 시뮬레이션을 통해 그 타당성을 확인하였다.