• Title/Summary/Keyword: Sinusoidal frequency

Search Result 609, Processing Time 0.022 seconds

A Method to Improve the Performance of Phase-Locked Loop (PLL) for a Single-Phase Inverter Under the Non-Sinusoidal Grid Voltage Conditions (비정현 계통 전압하에서 단상 인버터의 PLL 성능 개선 방법)

  • Khan, Reyyan Ahmad;Choi, Woojin
    • The Transactions of the Korean Institute of Power Electronics
    • /
    • v.23 no.4
    • /
    • pp.231-239
    • /
    • 2018
  • The phase-locked loop (PLL) is widely used in grid-tie inverter applications to achieve a synchronization between the inverter and the grid. However, its performance deteriorates when the grid voltage is not purely sinusoidal due to the harmonics and the frequency deviation. Therefore, a high-performance PLL must be designed for single-phase inverter applications to guarantee the quality of the inverter output. This paper proposes a simple method that can improve the performance of the PLL for the single-phase inverter under a non-sinusoidal grid voltage condition. The proposed PLL can accurately estimate the fundamental frequency and theta component of the grid voltage even in the presence of harmonic components. In addition, its transient response is fast enough to track a grid voltage within two cycles of the fundamental frequency. The effectiveness of the proposed PLL is confirmed through the PSIM simulation and experiments.

Linear Prediction Approach for Accurate Dual-Channel Sine-Wave Parameter Estimation in White Gaussian Noise

  • So, Hing-Cheung;Zhou, Zhenhua
    • ETRI Journal
    • /
    • v.34 no.4
    • /
    • pp.641-644
    • /
    • 2012
  • The problem of sinusoidal parameter estimation at two channels with common frequency in white Gaussian noise is addressed. By making use of the linear prediction property, an iterative linear least squares (LLS) algorithm for accurate frequency estimation is devised. The remaining parameters are then determined according to the LLS fit with the use of the frequency estimate. It is proven that the variance of the frequency estimate achieves Cram$\acute{e}$r-Rao lower bound at sufficiently small noise conditions.

Sinewave-PWM ZVS Inverter using High-Frequency Transformer for Utility AC Voltage Link

  • Chandhaket S.;Ogura K.;Konishi Y.;Nakaoka M.
    • Proceedings of the KIPE Conference
    • /
    • 2003.07b
    • /
    • pp.511-515
    • /
    • 2003
  • This paper presents a novel prototype of the utility-interfaced sinusoidal pulse width modulated (SPWM) inverter using the high-frequency flyback transformer fur the small-scale solar photo-voltaic power conditioner (1kW - 4kW). The proposed SPWM power conditioner circuit with a high-frequency link has a function of electrical isolation, which is vital fur solar photovoltaic power conditioner systems with the viewpoint of safety and convenience. The discontinuous conduction mode (DCM) operation of the flyback transformer is also maintained to simplify the topology of the inverter circuit and control scheme. First, the operating principle of the proposed circuit is described far the understanding of the circuit parameters establishment. Then, the digitally constructed SPWM control scheme is presented. The proposed circuit is verified by the computer simulation and the prototype experiment.

  • PDF

Adaptive Observer for a System with Sinusoidal Disturbance in Measurement Output (측정 출력에 삼각함수 외란이 포함된 시스템의 적응 관측기)

  • Son, Young-Ik;Kim, In-Hyuk
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.59 no.5
    • /
    • pp.966-971
    • /
    • 2010
  • An adaptive state observer is presented for a class of LTI systems that have a sinusoidal disturbance in the measurement output. Adaptation rules are developed for identifying the unknown sinusoidal disturbance signal from the system output. For the application of the identification result to the state estimation problem, the sinusoidal signal with arbitrary initial phase has been considered in this paper. In order to test the performance of proposed algorithm, comparative computer simulations have been carried out with an existing robust observer. The simulation results show the effectiveness of the proposed method.

Dynamic Buckling Characteristics of Arch Structures Considering Geometric Nonlinearity (기하학적 비선형을 고려한 정현형 아치 구조물의 동적 좌굴 특성)

  • 윤태영;김승덕
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2003.11a
    • /
    • pp.492-497
    • /
    • 2003
  • The dynamic instability for snapping phenomena has been studied by many researches. There is few paper which deal with the dynamic buckling under the load with periodic characteristics, and the behavior under periodic excitation is expected the different behavior against STEP excitation. We investigate the fundamental mechanisms of the dynamic instability when the sinusoidal shaped arch structures subjected to sinusoidal distributed excitation with pin-ends. In this study, the dynamic direct snapping of shallow arches is investigated under not only STEP load excitation but also sinusoidal harmonic excitations, applied in the up-and-down direction. The dynamic nonlinear responses are obtained by the numerical integration of the geometrically nonlinear equations of motion, and examined by the Fourier spectral analysis in order to get the frequency-dependent characteristics of the dynamic instability for various load levels.

  • PDF

Design of Silent Discharging Ozonizer using Algorithm for Sinusoidal Filter (정현파필터 알고리즘을 이용한 무성방전형 오존발생장치의 설계)

  • Eom, Tae-Wook;Lee, Byung-Soon
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.28 no.4
    • /
    • pp.56-61
    • /
    • 2014
  • In this paper, a control method using Sinusoidal Filter Controller of Silent Discharging Ozonizer is proposed and also the control methode performed robust control against variation of capacitance, command voltage and frequency. As the control system for this methode, Sinusoidal Filter Algorism can be simplified configuration of the power supply by using a low-pass filter. Through simulations and experiment results, the proposed control methode compensates for the high voltage waveform to the ozonizer.

Velocity Calibration of Sinusoidal Mode for Mossbauer Spectrometer and Mossbauer Study on $Fe_3O_4$ (사인파속도형 Mossbauer 분광계의 속도눈금 매기기와 Magnetite의 Mossbauer 분광법에 의한 연구)

  • 이충섭;이찬영
    • Journal of the Korean Magnetics Society
    • /
    • v.7 no.5
    • /
    • pp.232-236
    • /
    • 1997
  • We have gone into details about the velocity calibration of sinusoidal mode for Mossbauer spectrometer. Since sinusoidal Mossbauer spectrometer has a ${\gamma}$-ray source that oscillates at the end of loudspeaker with the natural frequency. Doppler velocity is accurate and stable. From the analyzing Mossbauer spectra of $Fe_3O_4$ and U $Fe_3O_4$ (unbalanced $Fe_3O_4$), we have shown the power of correct velocity for sinusoidal mode.

  • PDF

Current Control of a Single-phase PWM Converter under the Distorted Source Voltage and Frequency Condition (전원 전압 왜곡과 주파수 변동 시 단상 PWM 컨버터의 전류 제어)

  • Ahn, Chang-Heon;Kim, Sang-Hoon
    • The Transactions of the Korean Institute of Power Electronics
    • /
    • v.20 no.4
    • /
    • pp.356-362
    • /
    • 2015
  • This paper presents a current control strategy in the synchronous reference frame for a single-phase PWM converter, which ensures sinusoidal input current control under the distorted source voltage and frequency condition. Given that the distorted source voltage distorts the phase angle for PWM converter control, the input current contains the same harmonics as the source voltage. Aside from the distorted voltage, the variation in source frequency reduces the performance of input current control. To achieve sinusoidal input current control under the distorted source voltage and frequency condition, this paper proposes a compensation strategy of current reference with the distortion component extracted from the phase angle and a detection strategy of frequency variation from the output of a synchronous reference frame phase-lock loop. The experimental results confirm the validity of the proposed method under the distorted source voltage and frequency condition.

Sinusoidal Modeling of Polyphonic Audio Signals Using Dynamic Segmentation Method (동적 세그멘테이션을 이용한 폴리포닉 오디오 신호의 정현파 모델링)

  • 장호근;박주성
    • The Journal of the Acoustical Society of Korea
    • /
    • v.19 no.4
    • /
    • pp.58-68
    • /
    • 2000
  • This paper proposes a sinusoidal modeling of polyphonic audio signals. Sinusoidal modeling which has been applied well to speech and monophonic signals cannot be applied directly to polyphonic signals because a window size for sinusoidal analysis cannot be determined over the entire signal. In addition, for high quality synthesized signal transient parts like attacks should be preserved which determines timbre of musical instrument. In this paper, a multiresolution filter bank is designed which splits the input signal into six octave-spaced subbands without aliasing and sinusoidal modeling is applied to each subband signal. To alleviate smearing of transients in sinusoidal modeling a dynamic segmentation method is applied to subbands which determines the analysis-synthesis frame size adaptively to fit time-frequency characteristics of the subband signal. The improved dynamic segmentation is proposed which shows better performance about transients and reduced computation. For various polyphonic audio signals the result of simulation shows the suggested sinusoidal modeling can model polyphonic audio signals without loss of perceptual quality.

  • PDF

A Design of LC-tuned Sinusoidal VCOs Using OTA-C Active Inductors

  • Chung, Won-Sup;Son, Sang-Hee
    • Journal of IKEEE
    • /
    • v.11 no.3
    • /
    • pp.122-128
    • /
    • 2007
  • Sinusoidal voltage-controlled oscillators (VCOs) based on Colpitts and Hartley oscillators are presented. They consist of a LC parallel-tuned circuit connected in a negative-feedback loop with an OTA-R amplifier and two diode limiters, where the inductor is simulated one realized with temperature-stable linear operational transconductance amplifiers (OTAs) and a grounded capacitor. Prototype VCOs are built with discrete components. The Colpitts VCO exhibits less than 1% nonlinearity in its current-to-frequency transfer characteristic from 4.2 to 21.7 MHz and ${\pm}$95 ppm/$^{\circ}C$ temperature drift of frequency over 0 to $70^{\circ}C$. The total harmonic distortion (THD) is as low as 2.92% with a peak-to-peak amplitude of 0.7 V for a frequency-tuning range of 10.8-32 MHz. The Hartley VCO has the temperature drift and THD of two times higher than those of the Colpitts VCO.

  • PDF