• 제목/요약/키워드: Two-level three-phase VSI (Voltage Source Inverter)

검색결과 5건 처리시간 0.02초

Modified Unipolar Carrier-Based PWM Strategy for Three-Level Neutral-Point-Clamped Voltage Source Inverters

  • Srirattanawichaikul, Watcharin;Premrudeepreechacharn, Suttichai;Kumsuwan, Yuttana
    • Journal of Electrical Engineering and Technology
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    • 제9권2호
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    • pp.489-500
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    • 2014
  • This paper presents a simple modified unipolar carrier-based pulsewidth modulation (CB-PWM) strategy for the three-level neutral-point-clamped (NPC) voltage source inverter (VSI). Analytical expressions for the relationship between modulation reference signals and output voltages are derived. The proposed modulation technique for the three-level NPC VSI includes the maximum and minimum of the three-phase sinusoidal reference voltages with zero-sequence voltage injection concept. The proposed modified CB-PWM strategy incorporates a novel method that requires only of one triangular carrier wave for generate the gating pulses in three-level NPC VSI. It has the advantages of being simplifying the algorithm with no need of complex two/multi-carrier pulsewidth modulation or space vector modulation (SVM) and it's also simple to implement. The possibility of the proposed CB-PWM technique has been verified though computer simulation and experimental results.

최소 손실 불연속 변조 기법에 따른 2레벨 3상 전압원 인버터의 직류단 전압 맥동 분석 (DC-Link Voltage Ripple Analysis of Minimum Loss Discontinuous PWM Strategy in Two-Level Three-Phase Voltage Source Inverters)

  • 이준혁;박정욱
    • 전력전자학회논문지
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    • 제26권2호
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    • pp.120-126
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    • 2021
  • DC-link capacitors are one of the main components in two-level three-phase voltage source inverters (VSIs); they provide the pulsating input current and stabilize the vacillating DC-link voltage. Ideally, the larger the capacitance of DC-link capacitors, the better the DC-link voltage stabilizes. However, high capacitance increases the cost and decreases the power density of VSI systems. Therefore, the capacitance should be chosen carefully on the basis of the DC-link voltage ripple requirement. However, the DC-link voltage ripple is dependent on the pulse-width modulation (PWM) strategy. This study especially presents a DC-link voltage ripple analysis when the minimum loss discontinuous PWM strategy is applied. Furthermore, an equation for the selection of the minimum capacitance of DC-link capacitors is proposed. Experimental results with R-L loads are also provided to verify the effectiveness of the presented analysis.

Detection and Diagnosis Solutions for Fault-Tolerant VSI

  • Cordeiro, Armando;Palma, Joao C.P.;Maia, Jose;Resende, Maia J.
    • Journal of Power Electronics
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    • 제14권6호
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    • pp.1272-1280
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    • 2014
  • This paper presents solutions for fault detection and diagnosis of two-level, three phase voltage-source inverter (VSI) topologies with IGBT devices. The proposed solutions combine redundant standby VSI structures and contactors (or relays) to improve the fault-tolerant capabilities of power electronics in applications with safety requirements. The suitable combination of these elements gives the inverter the ability to maintain energy processing in the occurrence of several failure modes, including short-circuit in IGBT devices, thus extending its reliability and availability. A survey of previously developed fault-tolerant VSI structures and several aspects of failure modes, detection and isolation mechanisms within VSI is first discussed. Hardware solutions for the protection of power semiconductors with fault detection and diagnosis mechanisms are then proposed to provide conditions to isolate and replace damaged power devices (or branches) in real time. Experimental results from a prototype are included to validate the proposed solutions.

전류 리플 저감을 위한 세분화된 공간전압벡터를 이용한 모델 예측 제어 기반의 SVM 방법 (Space Vector Modulation based on Model Predictive Control to Reduce Current Ripples with Subdivided Space Voltage Vectors)

  • 문현철;이준석;이준희;이교범
    • 전력전자학회논문지
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    • 제22권1호
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    • pp.18-26
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    • 2017
  • This paper proposes the model predictive control with space vector modulation (SVM) method for current control of voltage-source inverter. Unlike the conventional method using a limited number of voltage vectors by switching states, the proposed method can consider various voltage vectors to identify the optimized voltage vector. The various voltage vectors are obtained by subdividing existing voltage vectors. The optimized voltage vector that minimizes the cost function is selected and applied to the inverter by using the SVM. The various voltage vectors and SVM reduce current ripples in the output AC side of the inverter compared with the conventional method. The effectiveness and performance of the proposed method are verified through simulation and experiment with a three-phase two-level voltage-source grid-connected inverter.

Comparative Study of Minimum Ripple Switching Loss PWM Hybrid Sequences for Two-level VSI Drives

  • Vivek, G.;Biswas, Jayanta;Nair, Meenu D.;Barai, Mukti
    • Journal of Power Electronics
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    • 제18권6호
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    • pp.1729-1750
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    • 2018
  • Voltage source inverters (VSIs) are widely used to drive induction motors in industry applications. The quality of output waveforms depends on the switching sequences used in pulse width modulation (PWM). In this work, all existing optimal space vector pulse width modulation (SVPWM) switching strategies are studied. The performance of existing SVPWM switching strategies is optimized to realize a tradeoff between quality of output waveforms and switching losses. This study generalizes the existing optimal switching sequences for total harmonic distortions (THDs) and switching losses for different modulation indexes and reference angles with a parameter called quality factor. This factor provides a common platform in which the THDs and switching losses of different SVPWM techniques can be compared. The optimal spatial distribution of each sequence is derived on the basis of the quality factor to minimize harmonic current distortions and switching losses in a sector; the result is the minimum ripple loss SVPWM (MRSLPWM). By employing the sequences from optimized switching maps, the proposed method can simultaneously reduce THDs and switching losses. Two hybrid SVPWM techniques are proposed to reduce line current distortions and switching losses in motor drives. The proposed hybrid SVPWM strategies are MRSLPWM 30 and MRSLPWM 90. With a low-cost PIC microcontroller (PIC18F452), the proposed hybrid SVPWM techniques and the quality of output waveforms are experimentally validated on a 2 kVA VSI based on a three-phase two-level insulated gate bipolar transistor.