• Title/Summary/Keyword: Feedback regulation

Search Result 261, Processing Time 0.025 seconds

Variable-Speed Wind Turbine Coupled Three-Phase Self-Excited Induction Generator Voltage Regulation Scheme with Static VAR Compensator Controlled by Pl Controller

  • Ahmed Tarek;Nishida Katsumi;Sato Shinji;Nagai Shinichro;Hiraki Eiji;Nakaoka Mutsuo
    • Proceedings of the KIPE Conference
    • /
    • 2003.07b
    • /
    • pp.532-535
    • /
    • 2003
  • In this paper, a Pl controlled feedback closed-loop voltage regulation scheme of the three-phase squirrel cage rotor self-excited induction generator (SEIG) driven by a variable-speed prime mover (VSPM) such as a wind turbine is designed on the basis of the static VAR compensator (SVC) and discussed in experiment fer the promising stand-alone power independent conditioner. The simulation and experimental results of the three-phase SEIG with the simple SVC controller for its stabilized voltage regulation prove the practical effectiveness of the additional SVC control loop scheme including the PI controller with fast response characteristics and steady-sate performance improvement.

  • PDF

Design of robust gain scheduling controllers in uncertain nonlinear systems

  • Lee, Seon-Ho;Lim, Jong-Tae
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1996.10a
    • /
    • pp.231-234
    • /
    • 1996
  • This paper considers the output regulation problems on uncertain systems. Using NR-estimator(on-line), a family of equilibrium points for the uncertain system is computed. The state variables of the closed loop system track the average value of the obtained equilibrium manifold by dynamic state feedback control.

  • PDF

Design and analysis of the DC/DC Converter using the model of the PWM switch (PWM 스위치 모델을 이용한 DC/DC 콘버터의 설계 및 해석)

  • Lee, I.H.
    • Proceedings of the KIEE Conference
    • /
    • 1992.07b
    • /
    • pp.1025-1028
    • /
    • 1992
  • In this paper the flyback converter analysis is presented using the model of the PWM switch, which is easier to use than the general method of state-space averaged model. A procedure to design the flyback convertor and the feedback circuit is illustrated. From these results, a stable flyback convertor regulation system is possible by using the PWM switch model.

  • PDF

Adaptive stabilization for nonlinear systems with multiple unknown virtual control coefficients (다수의 미지 가상 입력 계수들을 가지는 비선형 시스템에 대한 적응 안정화)

  • Seo, Sang-Bo;Jung, Jin-Woo;Seo, Jin-Heon;Shim, Hyung-Bo
    • Proceedings of the IEEK Conference
    • /
    • 2009.05a
    • /
    • pp.76-78
    • /
    • 2009
  • This paper considers the problem of global adaptive regulation for a class of nonlinear systems which have multiple unknown virtual control coefficient. By using a new parameter estimator and backstepping technique, we design a smooth state feedback control law, parameter update laws that estimate the unknown virtual control coefficients, and a continuously differentiable Lyapunov function which is positive definite and proper.

  • PDF

Trust Building in Cyberspace (사이버 공간에서의 신뢰성 확보 방안 - 기업 내부관점에서 -)

  • Park, Gyeong-Hwan
    • 한국디지털정책학회:학술대회논문집
    • /
    • 2003.12a
    • /
    • pp.403-415
    • /
    • 2003
  • This study is performed to examine the relationships between trust and antecedents in cyberspace. Trust is the major control system in cyberspace. Different time, different spaces, different cultures, indistinct boundaries, flexible structure, separation of information from matters, cybernetics, difficulty of control are differential characteristics between cyberspace and physical space. Providing fit information, use of effective electronic channels, previous trust management, feedback system about output, flexible culture, self-regulation, off-line meeting, providing information about tasks and roles, ability, and justice are supposed to have effects on trust in cyberspace. By electronic mediated systems, the company will have more business opportunity. But trust will be conditional factors of expanding business in cyberspace.

  • PDF

Study on the Characteristics of Constant Voltage Transformer for the changes of the circuit parameters (정전압 변압기의 회로정수에 따른 특성 변화에 관한 연구)

  • Joo Hyeong-Gil;Han Jae-Won
    • Proceedings of the KIPE Conference
    • /
    • 2001.07a
    • /
    • pp.627-629
    • /
    • 2001
  • The constant voltage transformer(CVT) is a voltage regulator that has a high reliability, a good short circuit characteristic, a high input power factor, and a relative immunity to lightning strike. Moreover, this has a good line regulation without a voltage feedback control. In this paper, the characteristics of CVT for the changes of input voltage and other circuit parameters are investigated.

  • PDF

Feedback Regulation of ATP-induced $Ca^{2+}$ Signaling in HL-60 Cells

  • Lee, Hyosang;Suh, Byung-Chang;Kim, Kyong-Tai
    • Proceedings of the Korean Biophysical Society Conference
    • /
    • 1997.07a
    • /
    • pp.33-33
    • /
    • 1997
  • In HL-60 cells, extracellular A TP increases intracellular $Ca^{2+}$ ([Ca$^{2+}$]$_{i}$) in a concentration-dependent manner with the maximal response occurring around 10 $\mu$M. However, above the maximal responsive concentration ATP elicits different patterns of $Ca^{2+}$ signaling.(omitted)d)

  • PDF

LAMMER Kinase Modulates Cell Cycle by Phosphorylating the MBF Repressor, Yox1, in Schizosaccharomyces pombe

  • Kibum Park;Joo-Yeon Lim;Je-Hoon Kim;Jieun Lee;Songju Shin;Hee-Moon Park
    • Mycobiology
    • /
    • v.51 no.5
    • /
    • pp.372-378
    • /
    • 2023
  • Lkh1, a LAMMER kinase homolog in the fission yeast Schizosaccharomyces pombe, acts as a negative regulator of filamentous growth and flocculation. It is also involved in the response to oxidative stress. The lkh1-deletion mutant displays slower cell growth, shorter cell size, and abnormal DNA content compared to the wild type. These phenotypes suggest that Lkh1 controls cell size and cell cycle progression. When we performed microarray analysis using the lkh1-deletion mutant, we found that only four of the up-regulated genes in the lkh1-deletion were associated with the cell cycle. Interestingly, all of these genes are regulated by the Mlu1 cell cycle box binding factor (MBF), which is a transcription complex responsible for regulating the expression of cell cycle genes during the G1/S phase. Transcription analyses of the MBF-dependent cell-cycle genes, including negative feedback regulators, confirmed the up-regulation of these genes by the deletion of lkh1. Pull-down assay confirmed the interaction between Lkh1 and Yox1, which is a negative feedback regulator of MBF. This result supports the involvement of LAMMER kinase in cell cycle regulation by modulating MBF activity. In vitro kinase assay and NetPhosK 2.0 analysis with the Yox1T40,41A mutant allele revealed that T40 and T41 residues are the phosphorylation sites mediated by Lkh1. These sites affect the G1/S cell cycle progression of fission yeast by modulating the activity of the MBF complex.

Adaptive Sliding Mode Traffic Flow Control using a Deadzoned Parameter Adaptation Law for Ramp Metering and Speed Regulation

  • Jin, Xin;Eom, Myunghwan;Chwa, Dongkyoung
    • Journal of Electrical Engineering and Technology
    • /
    • v.12 no.5
    • /
    • pp.2031-2042
    • /
    • 2017
  • In this paper, a novel traffic flow control method based-on ramp metering and speed regulation using an adaptive sliding mode control (ASMC) method along with a deadzoned parameter adaptation law is proposed at a stochastic macroscopic level traffic environment, where the influence of the density and speed disturbances is accounted for in the traffic dynamic equations. The goal of this paper is to design a local traffic flow controller using both ramp metering and speed regulation based on ASMC, in order to achieve the desired density and speed for the maintenance of the maximum mainline throughput against disturbances in practice. The proposed method is advantageous in that it can improve the traffic flow performance compared to the traditional methods using only ramp metering, even in the presence of ramp storage limitation and disturbances. Moreover, a prior knowledge of disturbance magnitude is not required in the process of designing the controller unlike the conventional sliding mode controller. A stability analysis is presented to show that the traffic system under the proposed traffic flow control method is guaranteed to be uniformly bounded and its ultimate bound can be adjusted to be sufficiently small in terms of deadzone. The validity of the proposed method is demonstrated under different traffic situations (i.e., different initial traffic status), in the sense that the proposed control method is capable of stabilizing traffic flow better than the previously well-known Asservissement Lineaire d'Entree Autoroutiere (ALINEA) strategy and also feedback linearization control (FLC) method.

Implications of Circadian Rhythm in Dopamine and Mood Regulation

  • Kim, Jeongah;Jang, Sangwon;Choe, Han Kyoung;Chung, Sooyoung;Son, Gi Hoon;Kim, Kyungjin
    • Molecules and Cells
    • /
    • v.40 no.7
    • /
    • pp.450-456
    • /
    • 2017
  • Mammalian physiology and behavior are regulated by an internal time-keeping system, referred to as circadian rhythm. The circadian timing system has a hierarchical organization composed of the master clock in the suprachiasmatic nucleus (SCN) and local clocks in extra-SCN brain regions and peripheral organs. The circadian clock molecular mechanism involves a network of transcription-translation feedback loops. In addition to the clinical association between circadian rhythm disruption and mood disorders, recent studies have suggested a molecular link between mood regulation and circadian rhythm. Specifically, genetic deletion of the circadian nuclear receptor Rev-$erb{\alpha}$ induces mania-like behavior caused by increased midbrain dopaminergic (DAergic) tone at dusk. The association between circadian rhythm and emotion-related behaviors can be applied to pathological conditions, including neurodegenerative diseases. In Parkinson's disease (PD), DAergic neurons in the substantia nigra pars compacta progressively degenerate leading to motor dysfunction. Patients with PD also exhibit non-motor symptoms, including sleep disorder and neuropsychiatric disorders. Thus, it is important to understand the mechanisms that link the molecular circadian clock and brain machinery in the regulation of emotional behaviors and related midbrain DAergic neuronal circuits in healthy and pathological states. This review summarizes the current literature regarding the association between circadian rhythm and mood regulation from a chronobiological perspective, and may provide insight into therapeutic approaches to target psychiatric symptoms in neurodegenerative diseases involving circadian rhythm dysfunction.