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This paper deals with a gain scheduling synchronous demodulation scheme useful to obtain speed and position measurements from resolver position sensors. The proposed algorithm is devoted to a field-programmable gate array implementation in order to provide the elaborated information for very low latency control loops. The presented design allows getting accurate estimations in a wide range of rotational speeds without requiring costly off-the-shelf integrated circuits and leads to higher accuracy at low speed if compared to commercial solutions. To this purpose, the resolver excitation circuit has been simplified working directly with a square wave signal, and the resolver frequency behavior due to the nonsinusoidal excitation has been considered. [ABSTRACT FROM AUTHOR]

A low input current total harmonic distortion (THD) rectifier is presented, tailored around an open-end winding permanent magnet synchronous generator. Specifically, a six-level converter topology is obtained by connecting the generator stator winding to a three level T-type unidirectional rectifier on one side, and to an auxiliary two-level inverter on the other side. The T-type rectifier manages the entire active power stream and operates at the line frequency in order to minimize the switching power losses. The auxiliary inverter is instead driven by a standard PWM technique, being tasked to sinusoidally shape the input current and to actively balance the voltage across the dc-bus capacitors of the T-type rectifier. Such an inverter, being rated at a lower power and at a lower voltage than the T-type rectifier, can exploit low-cost power mosfets. The proposed topology, featuring a very low input current THD, could well supplement in aircraft, portable or distributed generation applications, modern high-speed permanent magnet synchronous generators featuring a quite small stator impedance. Simulation and experimental results confirm the effectiveness of the proposed configuration. [ABSTRACT FROM AUTHOR]