A maximum power point tracker using positive feedforward control based on the DC motor dynamics and PVM mathematical model

This paper presents a maximum power tracking method for DC motor fed from photovoltaic modules (PVM) through step-down power converter. This method employs positive feedback of motor speed; therefore, only DC motor speed measurements are required. The designed control law is based on mathematical model of DC motor and power converter, and also, variations of optimal maximum power point (MPP) are considered at different values of irradiance. Optimal MPP is approximated by method known as linear reoriented coordinates method (LRCM). Finally, a simple analog circuit is designed and implemented, which calculates optimal duty ratio for power converter according to DC motor speed.