A Harmonic Voltage Injection Based DC-Link Imbalance Compensation Technique for Single-Phase Three-Level Neutral-Point-Clamped (NPC) Inverters

Kang, Kyoung-Pil; Cho, Younghoon; Ryu, Myung-Hyo; Baek, Ju-Won

doi:10.3390/en11071886

Cited by 5 publications

(12 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The dependence of I TDD and V WTHD on modulation index m for CPWM with a neutral-point balancing control [8], a virtual SVPWM (VSVPWM) [11], a hybrid strategy of these two methods [12] and the proposed method are shown in Figure 15. As can be seen, when the modulation index m > 0.1, I TDD and V WTHD of the proposed strategy is lower than the other three strategies.…”

Section: Comparison With Neutral Point Balancing Strategiesmentioning

confidence: 99%

“…The topology of three-level inverters can be divided into three categories: cascade H-bridge (CHB) [4], flying capacitor (FC) [5], and neutral-point-clamped (NPC) [6]. Among them, NPC three-level inverters are the most widely used in medium-voltage high-power industrial applications, such as traction drive, mine hoister, and wind power generation [7][8][9].…”

Section: Introductionmentioning

confidence: 99%

“…The research of three-level inverter has been focused on output current ripple reduction [10], neutral-point potential fluctuation restraint [8,11,12], common mode voltage reduction [13], switching loss suppression [14], and low switching frequency operation [15]. With these strategies, basic vectors used to synthesize the reference vector or dwell times of redundant switching states are changed to meet the requirement of a certain aspect of performance.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Sector Subdivision Based SVPWM Strategy of Neutral-Point-Clamped Three-Level Inverter for Current Ripple Reduction

Zhang

Wei

et al. 2019

Energies

View full text Add to dashboard Cite

This paper presents a sector subdivision based space vector pulse width modulation (SVPWM) strategy with reduced current ripple for a three-level inverter. Using the output current ripple theory, closed-form expressions of average current ripple vectors for both continuous and discontinuous switching sequences are derived. Based on the sector and triangle distributions of conventional SVPWM strategy, each triangle is further divided into three small-regions. Then the switching sequence with the lowest magnitude of the average current ripple vector is applied in every small-region, so that the advantages of continuous pulse width modulation (CPWM) and discontinuous pulse width modulation (DPWM) under different modulation index conditions are combined to reduce the current ripple in the whole modulation range. The output performance of the proposed strategy is compared with the conventional CPWM and DPWM strategy, and experimental results verify that the proposed strategy could reduce the current ripple of three-level inverters effectively.

show abstract

Section: Comparison With Neutral Point Balancing Strategiesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Sector Subdivision Based SVPWM Strategy of Neutral-Point-Clamped Three-Level Inverter for Current Ripple Reduction

Zhang

Wei

et al. 2019

Energies

View full text Add to dashboard Cite

show abstract

“…Three-level neutral-point-clamped (NPC) converters are popularly used in renewable energy generation and energy storage, which have been widely recognized as promising solutions to the problems associated with increasing environmental challenges [1][2][3]. Compared to the two-level topology, three-level NPC converters are much more attractive because of their lower voltage stress on power electronic devices, lower total harmonic distortion, higher efficiency, and even better economic performance [4][5][6].…”

Section: Introductionmentioning

confidence: 99%

A Study on Neutral-Point Potential in Three-Level NPC Converters

et al. 2019

View full text Add to dashboard Cite

This paper proposes an accurate mathematical model of three-level neutral-point-clamped (NPC) converters that can accurately represent the midpoint potential drift of the DC link with parameter perturbation. The mathematical relationships between the fluctuation in neutral-point voltage, the parametric perturbation, and the capacitance error are obtained as mathematical expressions in this model. The expressions can be used to quantitatively analyze the reason for the neutral-point voltage imbalance and balancing effect based on a zero-sequence voltage injection. The injected zero-sequence voltage, which can be used to balance the DC-side voltages with the combined action of active current, can be easily obtained from the proposed model. A balancing control under four-quadrant operation modes is proposed by considering the active current to verify the effectiveness of this model. Both the simulation and experiment results validate the excellent performance of the proposed model compared to the conventional model.Energies 2019, 12, 3367 2 of 22 pulse width modulation (SVPWM) strategies were proposed to adjust the dwell time between small vector switching states by judging the direction of the neutral point current and the deviation of the neutral point potential. However, the calculation methods are complex and difficult to implement. In [24], a pulse width modulation (PWM) strategy was proposed where the both DC-side voltages can be adjusted independently through zero-sequence voltage injections and compensation for the unbalance in neutral point voltages, but the process of calculating the injected zero-sequence voltages is complicated.However, these control strategies, above all, ignore the quantitative analysis of the potential drift and balancing effect based on zero-sequence voltage injection. Meanwhile, if the converter is used in renewable energy generation and energy storage with four-quadrant operation modes, the DC voltage balancing control is very difficult to realize in existing literature because the active current of the converter is not taken into consideration.This paper proposes an accurate mathematical model of the neutral-point potential in three-level NPC converters based on the SPWM strategy with parametric perturbation and zero-sequence voltage injection. The model is simple and direct, but very interesting and valuable. To the best of our knowledge, it is novel and has not been previously reported in the literature. From this model, the relationship between the drift potential value and all the AC-side and DC-side variables can be deduced by quantitative analyses. The calculated drift potential value shows that the basic reason for the neutral-point potential drift is the uneven shunt loss caused by the parametric perturbation, and the capacitance error has no influence on it. The balancing control can be directly obtained based on the combined action of the injected zero-sequence voltage and active current. The required zero-sequence voltage for balancing control can be easily calculated b...

show abstract

“…This voltage imbalance is considered a system imperfection, which is caused by the difference in hardware components or switching operations of the NPC inverter [10,11]. Many strategies have been proposed to solve the capacitor voltage imbalance problem, and these strategies have achieved successful results [12][13][14][15][16][17][18][19][20][21][22][23][24][25].…”

Section: Introductionmentioning

confidence: 99%

DC-Link Capacitor Voltage Imbalance Compensation Method Based Injecting Harmonic Voltage for Cascaded Multi-Module Neutral Point Clamped Inverter

Kang

Cho

Kim³

et al. 2019

Electronics

Self Cite

View full text Add to dashboard Cite

In a three-level (NPC) converter, the voltage imbalance problem in the DC-link capacitors is major issue. This paper proposes the DC-link capacitor voltage imbalance compensation method, where a common offset voltage is injected for a multi-module NPC inverter. The offset voltage consists of a harmonic voltage and a voltage difference between the upper and lower capacitors. The proposed method does not require any hardware modification, so that it is easily implemented. In order to show the effectiveness of the proposed balancing method, theoretical analysis is provided to balance the voltages, and both the simulations and the experiments were carried out to show that the voltage difference of the DC-link was decreased by the proposed method.

show abstract

A Harmonic Voltage Injection Based DC-Link Imbalance Compensation Technique for Single-Phase Three-Level Neutral-Point-Clamped (NPC) Inverters

Cited by 5 publications

References 24 publications

Sector Subdivision Based SVPWM Strategy of Neutral-Point-Clamped Three-Level Inverter for Current Ripple Reduction

Sector Subdivision Based SVPWM Strategy of Neutral-Point-Clamped Three-Level Inverter for Current Ripple Reduction

A Study on Neutral-Point Potential in Three-Level NPC Converters

DC-Link Capacitor Voltage Imbalance Compensation Method Based Injecting Harmonic Voltage for Cascaded Multi-Module Neutral Point Clamped Inverter

Contact Info

Product

Resources

About