I am creating a scale model wind turbine using a DC motor as a generator and would like to predict the motor response analytically. Generally speaking, the flow will spin the rotor (as in the turbine's), which will spin the motor, and then there will be what I'm calling the motor response, and then an output voltage and current from the motor. What I gather from various sources, though, is that there's a dynamic interaction between the shaft input and the motor response such that the original rpm and torque input at the shaft will be affected by the motor response which will create an adjusted rpm and torque input at the shaft which will be affected by the motor response and so on until it equilibrates. Is this about right? If so, how can I mathematically describe this iterative process using the original shaft inputs and the motor specifications? Furthermore, now what happens when a load is applied in series such that the generator is actually powering something?