Lyapunov Function and Sliding Mode Control Approach for the Solar-PV Grid Interface System

Miloud Rezkallah,Ambrish Chandra,Bhim Singh,Shailendra Kumar Sharma,Daniel R Rousse

doi:10.1109/tie.2016.2607162

Abstract

This paper deals with control of a solar-photovoltaic (PV) power-generating system interfaced with the grid. A sliding mode control approach is used for achieving maximum power tracking control of a solar-PV array. The Lyapunov function-based control approach is designed and modeled for the dc–ac inverter to serve the functions of an active power injection to the grid, balanced grid currents at unity power factor and load currents harmonics compensation. The proposed approaches eliminate the need of adjustment of system parameters under changing loads and generation scenario. The effectiveness of the proposed control strategies is established using its stability analyses. The performance of the solar-PV power-generating system with the proposed control algorithms is demonstrated using simulation and experimental studies under various operating conditions.

Highlights

RENEWABLE energy programs are receiving reasonable attention worldwide to cater the needs of electricity
Improved nonlinear sliding mode control approach (SMC) to drive the PV voltage to follow its reference is proposed in [25]. This approach is simple, but the use of the low pass-filter between the Perturb and Observe (P&O) controller and the SMC influences the dynamic response of the system
Inspired from the above work, this paper presents sliding mode based layer concept and Lyapunov function approach used for the control of DC-DC boost converter and the DC-AC inverter, respectively

Summary

INTRODUCTION

RENEWABLE energy programs are receiving reasonable attention worldwide to cater the needs of electricity. Improved nonlinear SMC to drive the PV voltage to follow its reference is proposed in [25] This approach is simple, but the use of the low pass-filter between the Perturb and Observe (P&O) controller and the SMC influences the dynamic response of the system. Authors have not considered all system parameters in selection of the gain controller, which leads that the proposed approach may suffer during transition period To overcome this drawback, the authors in [30], have enhanced this control approach by integrating new outer voltage loop in order to eliminate the steady-state error in the output voltage during perturbation or transition period. The DC-AC inverter is controlled using Lyapunovfunction based approach in order to feed the solar-PV generated power to the grid, to compensate harmonics present in load currents and to ensure balanced grid currents at unity power factor

MODELING AND CONTROL OF CONVERTERS

SIMULATION AND EXPERIMENTAL RESULTS

Findings

CONCLUSION