• Title, Summary, Keyword: Harmonic elimination

Search Result 121, Processing Time 0.061 seconds

Harmonic Elimination Method of Using Coupling Transformer in Twelve Pulse Inverter (12 펄스 인버터에서 결합변압기를 이용한 고조파 제거기법)

  • Jeong, Chang-Yong;Lee, Young-Woon;Choi, Kyu-Hyoung;Oh, Tae-Kyoo
    • Proceedings of the KIEE Conference
    • /
    • /
    • pp.613-615
    • /
    • 1996
  • Harmonic elimination method of using coupling transformer in twelve pulse inverter is presented for high power application. This method is using coupling transformer and PWM(pulse width modulation) switching and voltage source inverter. The object of proposed harmonic elimination method is obtained inverter output of low THD(Total Harmonic Distortion). The simulation results confirm the proposed harmonic elimination method.

  • PDF

A Study on Harmonic Elimination of FC-TCR in Power System (전력계통에 있어서 FC - TCR 장치의 고조파 제어에 관한 연구)

  • Kim, Joon-Hyun;Kim, Young-Man;Lee, Seung-Joo
    • Proceedings of the KIEE Conference
    • /
    • /
    • pp.127-130
    • /
    • 1988
  • This paper describes digital simulation of harmonic elimination in the FC-TCR. (Fixed Capacitor and Thyristor Controlled Reactor) A model at harmonic frequency is developed for a STATIC VAR compansator. The model is shown to be useful in predicting resonance condition. A new variable filter is used for synthesized harmonic elimination.

  • PDF

Case Study of Second Harmonic Generation under Nonlinear Load and Second Harmonic Elimination Method Based on Impedance Variation Scheme (비선형 부하 이차 고조파 발생 실증사례 분석 및 임피던스 변동 기법을 통한 이차 고조파 저감 기법)

  • Bang, Heegyun;Kim, Sikyung
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.62 no.5
    • /
    • pp.604-611
    • /
    • 2013
  • This paper presents an second harmonic elimination method based on the impedance variation scheme. Through the power quality analysis from the nonlinear loads connected on the power system, the second harmonic problems have been analyzed with a case study analysis and the experiments. In the paper, the second Harmonic generation was simulated with a single phase SCR rectifier and the analytical model is proposed for the second harmonic generation. A novel impedance variation scheme is proposed and analyzed to eliminate the second harmonic. The experiment has been performed on the 60(MVA) industry manufacturing plant. The experimental result demonstrates the proposed impedance variation scheme successfully operate on the 60(MVA) industry manufacturing plant.

Generalized Selective Harmonic Elimination Modulation for Transistor-Clamped H-Bridge Multilevel Inverter

  • Halim, Wahidah Abd.;Rahim, Nasrudin Abd.;Azri, Maaspaliza
    • Journal of Power Electronics
    • /
    • v.15 no.4
    • /
    • pp.964-973
    • /
    • 2015
  • This paper presents a simple approach for the selective harmonic elimination (SHE) of multilevel inverter based on the transistor-clamped H-bridge (TCHB) family. The SHE modulation is derived from the sinusoidal voltage-angle equal criteria corresponding to the optimized switching angles. The switching angles are computed offline by solving transcendental non-linear equations characterizing the harmonic contents using the Newton-Raphson method to produce an optimum stepped output. Simulation and experimental tests are conducted for verification of the analytical solutions. An Altera DE2 field-programmable gate array (FPGA) board is used as the digital controller device in order to verify the proposed SHE modulation in real-time applications. An analysis of the voltage total harmonic distortion (THD) has been obtained for multiple output voltage cases. In terms of the THD, the results showed that the higher the number of output levels, the lower the THD due to an increase number of harmonic orders being eliminated.

Application of Bacterial Foraging Algorithm and Genetic Algorithm for Selective Voltage Harmonic Elimination in PWM Inverter

  • Maheswaran, D.;Rajasekar, N.;Priya, K.;Ashok kumar, L.
    • Journal of Electrical Engineering and Technology
    • /
    • v.10 no.3
    • /
    • pp.944-951
    • /
    • 2015
  • Pulse Width Modulation (PWM) techniques are increasingly employed for PWM inverter fed induction motor drive. Among various popular PWM methods used, Selective Harmonic Elimination PWM (SHEPWM) has been widely accepted for its better harmonic elimination capability. In addition, using SHEPWM, it is also possible to maintain better voltage regulation. Hence, in this paper, an attempt has been made to apply Bacterial Foraging Algorithm (BFA) for solving selective harmonic elimination problem. The problem of voltage harmonic elimination together with output voltage regulation is drafted as an optimization task and the solution is sought through proposed method. For performance comparison of BFA, the results obtained are compared with other techniques such as derivative based Newton-Raphson method, and Genetic Algorithm. From the comparison, it can be observed that BFA based approach yields better results. Further, it provides superior convergence, reduced computational burden, and guaranteed global optima. The simulation results are validated through experimental findings.

Harmonic Elimination in Three-Phase Voltage Source Inverters by Particle Swarm Optimization

  • Azab, Mohamed
    • Journal of Electrical Engineering and Technology
    • /
    • v.6 no.3
    • /
    • pp.334-341
    • /
    • 2011
  • This paper presents accurate solutions for nonlinear transcendental equations of the selective harmonic elimination technique used in three-phase PWM inverters feeding the induction motor by particle swarm optimization (PSO). With the proposed approach, the required switching angles are computed efficiently to eliminate low order harmonics up to the $23^{rd}$ from the inverter voltage waveform, whereas the magnitude of the fundamental component is controlled to the desired value. A set of solutions and the evaluation of the proposed method are presented. The obtained results prove that the algorithm converges to a precise solution after several iterations. The salient contribution of the paper is the application of the particle swarm algorithm to attenuate successfully any undesired loworder harmonics from the inverter output voltage. The current paper demonstrates that the PSO is a promising approach to control the operation of a three-phase voltage source inverter with a selective harmonic elimination strategy to be applied in induction motor drives.

Increasing the Range of Modulation Indices with the Polarities of Cells and Switching Constraint Reliefs for the Selective Harmonic Elimination Pulse Width Modulation Technique

  • Najjar, Mohammad;Iman-Eini, Hossein;Moeini, Amirhossein
    • Journal of Power Electronics
    • /
    • v.17 no.4
    • /
    • pp.933-941
    • /
    • 2017
  • In this paper an improved low frequency selective harmonic elimination-PWM (SHE-PWM) technique for Cascaded H-bridge (CHB) converters is proposed. The proposed method is able to eliminate low order harmonics from the output voltage of the converter for a wide range of modulation indices. To solve SHE-PWM equations, especially for low modulation indices, a modified method is used which employs either the positive or negative voltage polarities of H-bridge cells to increase the freedom degrees of each cell. Freedom degrees of the switching angles are also used to increase the range of available solutions for non-linear SHE equations. The proposed SHE methods can successfully eliminate up to $25^{th}$ harmonic from a 7-level output voltage by using just nine switching transitions or a 150 Hz switching frequency. To confirm the validity of the proposed method, simulation and experimental results have been presented.

A Novel Analytical Method for Selective Harmonic Elimination Problem in Five-Level Converters

  • Golshan, Farzad;Abrishamifar, Adib;Arasteh, Mohammad
    • Journal of Power Electronics
    • /
    • v.17 no.4
    • /
    • pp.914-922
    • /
    • 2017
  • Multilevel converters have attracted a lot of attention in recent years. The efficiency parameters of a multilevel converter such as the switching losses and total harmonic distortion (THD) mainly depend on the modulation strategy used to control the converter. Among all of the modulation techniques, the selective harmonic elimination (SHE) method is particularly suitable for high-power applications due to its low switching frequency and high quality output voltage. This paper proposes a new expression for the SHE problem in five-level converters. Based on this new expression, a simple analytical method is introduced to determine the feasible modulation index intervals and to calculate the exact value of the switching angles. For each selected harmonic, this method presents three-level or five-level waveforms according to the value of the modulation index. Furthermore, a flowchart is proposed for the real-time implementation of this analytical method, which can be performed by a simple processor and without the need of any lookup table. The performance of the proposed algorithm is evaluated with several simulation and experimental results for a single phase five-level diode-clamped inverter.

An Elimination Method of Harmonics in AC to DC Converter (AC/DC 컨버터의 고조파 제거 방법)

  • 오진석
    • Journal of the Korean Society of Marine Engineering
    • /
    • v.27 no.6
    • /
    • pp.767-775
    • /
    • 2003
  • This paper considers the method of elimination harmonics in AC/DC converters, There are few practical methods to reduce the harmonics in AC/DC converters, particularly in filter design and control strategy. In this paper, a harmonic elimination methods are proposed, which includes hybrid PWM control strategy. These methods achieve precise output control along with the optimum performance simultaneously. The control method in this paper is developed to eliminate a fixed number of harmonics in AC to DC converter. The higher order harmonics can be easily eliminated by using filter proposed in this paper. The validity of these methods is confirmed experimentally.

Reconfigurable Selective Harmonic Elimination Technique for Wide Range Operations in Asymmetric Cascaded Multilevel Inverter

  • Kavitha, R;Rani, Thottungal
    • Journal of Power Electronics
    • /
    • v.18 no.4
    • /
    • pp.1037-1050
    • /
    • 2018
  • This paper presents a novel reconfigurable selective harmonic elimination technique to control harmonics over a wide range of Modulation Indexes (MI) in Multi-Level Inverter (MLI). In the proposed method, the region of the MI is divided into various sectors and expressions are formulated with different switching patterns for each of the sectors. A memetic BBO-MAS (Biogeography Based Optimization - Mesh Adaptive direct Search) optimization algorithm is proposed for solving the Selective Harmonic Elimination - Pulse Width Modulation (SHE-PWM) technique. An experimental prototype is developed using a Field Programmable Gate Array (FPGA) and their FFT spectrums are analyzed over a wide range of MI using a fluke power logger. Simulation and experimental results have validated the performance of the proposed optimization algorithms and the reconfigurable SHE-PWM technique. Further, the sensitivity of the harmonics has been analyzed considering non-integer variations in the magnitude of the input DC sources.