Submodule Capacitor voltage balancing of Modular Multilevel Converter

Tayyab, Mohammad; Sarwar, Adil

doi:10.1109/upcon47278.2019.8980280

Cited by 9 publications

(4 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The literature 13,14 reduces the switching losses and voltage deviations of the submodule respectively by controlling the dynamic threshold, the difference between the submodule voltage and its average value, but the sorting process of the submodule capacitance voltage is not optimized. The quality of MMC output voltage waveform in literature [15][16][17] is closely related to the selection of retention factor, Modulation index and MPC input value, but the selection rules of optimal value are not described. The literature 18,19 introduced improved quick sort algorithm and improved bucket sort algorithm for capacitance voltage equalization control, meanwhile the sub-module capacitance voltage sequence is sorted respectively in blocks and buckets, which reduces the amount of sorting to improve the computational efficiency, but the system still has excessive switching frequency.…”

Section: Introductionmentioning

confidence: 99%

A enhanced control strategy for capacitance voltage equalization in modular multilevel converter

Ding,

Zhang,

Cheng

et al. 2023

Measurement and Control

View full text Add to dashboard Cite

In searching for the optimal control strategy of sub-module capacitance voltage equalization of Modular Multilevel Converter (MMC), the most important issue is how to address the significant increase in computing time of the controller, switching frequency of the sub-module, device switching loss and MMC fault rate led by the increase in the number of sub-modules of the upper/lower bridge arm of the MMC. Therefore, this paper proposes a control strategy based on the retaining factor method + improved quick sort, namely, an improved quick sort algorithm is used to sort the sub-module capacitance voltages to reduce the amount of computation of the MMC controller; at the same time, a retaining factor is introduced to participate in the improved quick sort to significantly reduce the switching frequency of the sub-module. MMC of large ship grid-connected photovoltaic power system is taken as a research object in this paper, a 31-level MMC model is built in Matlab/Simulink. Simulation results verify that the improved quick sort has a good rapidity compared to the algorithms of bubble sort, quick sort, bidirectional bubble sort, and improved merge sort, that the retention factor method has a good frequency reduction effect, and that the proposed retention factor + improved quick sort can provide a good performance compared to improved quick sort and retention factor + improved merge sort under conditions of the normal operation and introducing disturbance.

show abstract

Section: Introductionmentioning

confidence: 99%

A enhanced control strategy for capacitance voltage equalization in modular multilevel converter

Ding,

Zhang,

Cheng

et al. 2023

Measurement and Control

View full text Add to dashboard Cite

show abstract

“…For industrial and domestic use, MLIs are going to be the most suitable choice in the near future. Enormous literature on conventional MLIs such as neutral-point clamped (NPC), flying capacitor (FC), cascaded H-bridge (CHB), Modular multilevel converter (MMC), and hybrid inverters are presented in [4][5][6][7][8]. In the case of NPC, insulated-gate bipolar transistor (IGBT) switches, clamped diodes, and external controllers for capacitor voltage balancing are required.…”

Section: Introductionmentioning

confidence: 99%

Active and reactive power control of grid‐connected single‐phase asymmetrical eleven‐level inverter

Tayyab¹,

Sarwar²,

Murshid

et al. 2022

IET Generation Trans & Dist

Self Cite

View full text Add to dashboard Cite

In recent times, multilevel inverters (MLIs) have become very popular for commercial and industrial applications. Here, an eleven-level inverter and its power flow control are presented. The presented topology has a lesser component count than other existing topologies, thus reducing the devices and overall cost of the inverter. This inverter comprises six bidirectional switches, two DC sources, one four-quadrant switch, and two capacitors for the voltage divider circuit. The conduction modes and corresponding switching states of the presented eleven-level inverter are shown in detail. Further, the apparent power control of the presented inverter under grid-connected operation is discussed, which provides simultaneous active and reactive power control over the power injected into the grid. Switching and conduction losses are calculated for 3 and 6 kVA grid injected power at 0.8 power factor lagging. The obtained results show that the total harmonic distortion (THD) of the inverter output voltage and grid current is 12.10% and 0.23%, respectively, under 6 kVA power transfer conditions. The real-time analysis is also carried out for 3 and 6 kVA power transfer conditions for the presented eleven-level inverter to validate the active and reactive power flow control.

show abstract

“…MLIs also possess certain advantages over conventional inverters, such as reduced total harmonic distortion, improved fundamental voltage, reduced voltage rating of individual switches, and improved efficiency 1–4 . The conventional MLI topologies such as neutral point clamped (NPC), 5 flying capacitor (FC), 6 cascaded H‐bridge (CHB), 7 and modular multilevel converter (MMC) 8–10 require a higher number of components for higher voltage levels. Further, they also suffer from capacitor voltage balancing issues.…”

Section: Introductionmentioning

confidence: 99%

A novel voltage boosting switched‐capacitor 19‐level inverter with reduced component count

Tayyab

Sarwar

Hussan

et al. 2022

Circuit Theory & Apps

Self Cite

View full text Add to dashboard Cite

A dual‐source switched‐capacitor multilevel inverter (SCMLI) topology utilizing 13 switches, one diode, and two switched capacitors is presented in this paper. The proposed topology is capable of operating in both asymmetrical and symmetrical modes. In asymmetrical mode, it produces 19‐level output voltage, whereas, in symmetrical mode, it produces 13‐level output voltage. The capacitor voltages are self‐balanced in the presented SCMLI topology. A detailed comparative analysis has been carried to show the advantages of the proposed topology in terms of the number of switches, number of capacitors, number of sources, and boosting of the converter with the recently published multilevel inverter topologies. The nearest level control (NLC)‐based algorithm is used for generating switching signals for the IGBTs present in the circuit. The reliability assessment is carried to assess the life span of the proposed SCMLI. Experimental results are obtained for different loading conditions using a laboratory hardware prototype. The fluke‐based power analyzer is used to record the inverter voltage and corresponding THD values at different modulation indexes. The efficiency of the proposed inverter is 97.35% for 200‐W load.

show abstract

Submodule Capacitor voltage balancing of Modular Multilevel Converter

Cited by 9 publications

References 21 publications

A enhanced control strategy for capacitance voltage equalization in modular multilevel converter

A enhanced control strategy for capacitance voltage equalization in modular multilevel converter

Active and reactive power control of grid‐connected single‐phase asymmetrical eleven‐level inverter

A novel voltage boosting switched‐capacitor 19‐level inverter with reduced component count

Contact Info

Product

Resources

About