Introducing the Adaptive Nonlinear Input Impedance Control Approach for MPPT of Renewable Generators

This paper proposes a novel maximum power point tracking (MPPT) strategy for renewable energy systems using Input Impedance Control (I2C) in power electronic converters, combined with an adaptive nonlinear controller. Unlike conventional voltage- or current-based methods, the I2C-MPPT approach leverages the maximum power transfer theorem by dynamically matching the converter’s equivalent input impedance to the source’s internal impedance. The adaptive nonlinear controller, designed using the Lyapunov stability theory, estimates system uncertainties and provides superior performance compared to traditional Proportional–Integral (PI) controllers. The proposed approach is validated through both simulations in MATLAB and experimental implementation using a Digital Signal Processor (DSP)-based controller. Practical results confirm the controller’s effectiveness in maintaining maximum power transfer under dynamic variations in source parameters, demonstrating improved settling time and robust operation. These findings underscore the potential of the I2C approach for enhancing the efficiency and reliability of renewable energy systems.