A comparative study of methods for estimating virtual flux at the point of common coupling in grid connected voltage source converters with LCL filter
Article Principal (1,421Mb) (Restricted access) Request copy
Què és aquest botó?
Aquest botó permet demanar una còpia d'un document restringit a l'autor. Es mostra quan:
- Disposem del correu electrònic de l'autor
- El document té una mida inferior a 20 Mb
- Es tracta d'un document d'accés restringit per decisió de l'autor o d'un document d'accés restringit per política de l'editorial
Rights accessRestricted access - publisher's policy
Grid synchronization based on Virtual Flux (VF) estimation allows for control of grid-connected power converter without depending on AC-voltage measurements. This is useful in voltage-sensor-less applications for reducing cost and complexity of the control hardware, and can be utilized in case of limited reliability or availability of voltage measurements at the intended point of synchronization to the grid. However, for Voltage Source Converters (VSC) with LCL filters, the influence of the capacitor current must be taken into account to ensure accurate VF estimation at the Point of Common Coupling (PCC) with the grid. This paper presents a comparative evaluation of three VF-based methods for grid synchronization of VSCs with LCL filters, with three different ways of obtaining the capacitor current. The VF estimation in the first method is based only on the measured converter currents. The second method includes capacitor voltage measurements used for estimating the capacitor currents, while the capacitor currents are measured in the third approach. Comparative results from time-domain simulations are presented demonstrating good performance of the estimation and accurate control of the active and reactive power at the PCC with all three methods, as long as sufficiently accurate filter parameters and current measurements are available. However, the approach based on capacitor current measurements is sensitive to noise due to the high ripple current compared to the fundamental frequency current in the capacitors. The operation of a converter with VF-based grid synchronization including estimation of the capacitor current is demonstrated by experimental results, verifying the voltage sensor-less operation with LCL-filter.
CitationFazlin, N., Suul, J., Rocabert, J., Rodriguez, P. A comparative study of methods for estimating virtual flux at the point of common coupling in grid connected voltage source converters with LCL filter. "IEEE transactions on industry applications", 23 Agost 2017, vol. PP, núm. 99, p. 1-26.
|08015199.pdf||Article Principal||1,421Mb||Restricted access|
All rights reserved. This work is protected by the corresponding intellectual and industrial property rights. Without prejudice to any existing legal exemptions, reproduction, distribution, public communication or transformation of this work are prohibited without permission of the copyright holder