Nonlinear control design of grid-connected photovoltaic system through LC filter with ANN based MPPT method

This paper discusses the issue of maximum power point tracking (MPPT) extracted from a photovoltaic module using a DC/AC power energy conversion system. The study targets specifically a solar enrgy conversion system including a PV panel, a PWM DC/AC inverter connected to single-phase grid through LC filter. The following are the primary goals of this work: (i) DC-Link voltage regulation: The voltage of the PV panel must follow a predetermined reference voltage that coincides with the maximum power point. An optimizer based on an artificial neural network (ANN) generates the optimal reference voltage; (ii) PFC requirement: Grid current must be sinusoidal and phase-locked to the voltage network. To do this, a mathematical modeling of the inverter with filter LC was performed. Subsequently, a backstepping controller is developed in order to ensure the control objective. The convergence of closed loop control is formally studied. As result, the injected current has good sinusoidal form and a low total harmonic distortion THD.