Sensorless speed control of outrunner PMSM drive connected to long cable for flying remote operative vehicle

This work is part of the development of a new flying remote operative vehicle (ROV) to provide aerial images of geo-localized area. The thrust of the flight is provided by a propeller coupled to a permanent magnet synchronous motor (PMSM) with external rotor (outrunner). This motor is driven by a frequency inverter using a pulse width modulation (PWM) technique via a long energy cable. Sensorless control technique based on the extended Kalman filter (EKF) is used in order to overcome the speed sensor problems and to reduce the weight of the ROV. Using a PWM technique and a long energy cable, overvoltages occur at the motor terminals which can affect the motor insulation, increase the motor heating and generate electromagnetic interference to the embedded electronics. To overcome these problems, a sinusoidal filter placed at the inverter output is used. The common mode current created by the long energy cable and the parasitic capacitances of the system is also discussed. The modeling of the overall system let us to make a simulation by using Matlab/Simulink software including the SimPowerSystems libraries.