Robust Stability Analysis of Grid-Connected Converters Based on Parameter- Dependent Lyapunov Functions

Autor(es)

Braga, Marcio F. ; Morais, Cecilia F. ; Maccari, Jr., Luiz A. ; Tognetti, Eduardo S. ; Montagner, Vinicius F. ; Oliveira, Ricardo C. L. F. ; Peres, Pedro L. D.

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF CONTROL AUTOMATION AND ELECTRICAL SYSTEMS; v. 28, n. 2, p. 159-170, APR 2017.
• Citações Web of Science: 1

Resumo

This paper deals with the problem of robust stability analysis of grid-connected converters with LCL filters controlled through a digital signal processor and subject to uncertain grid inductance. To model the uncertain continuous-time plant and the digital control gain, a discretization procedure, described in terms of a Taylor series expansion, is employed to determine an accurate discrete-timemodel. Then, a linear matrix inequality-based condition is proposed to assess the robust stability of the polynomial discrete-time augmented system that includes the filter state variables, the states of resonant controllers and the delay from the digital control implementation. By means of a parameterdependent Lyapunov function, the proposed strategy has as main advantage to provide theoretical certification of stability of the uncertain continuous-time closed-loop system, circumventing the main disadvantages of previous approaches that employ approximate discretized models, neglecting the errors. Numerical simulations illustrate the benefits of the discretization technique and experimental results validate the proposed approach. (AU)

• Processo FAPESP: 14/22881-1 - Controle de sistemas chaveados, sujeitos a saltos markovianos e outras classes de sistemas híbridos usando LMIs
• Beneficiário: Cecília de Freitas Morais
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 11/08312-6 - Discretização e Controle por Rede de Sistemas Politópicos com Taxa de Amostragem Incerta e Atraso
• Beneficiário: Marcio Feliciano Braga
• Modalidade de apoio: Bolsas no Brasil - Doutorado