A system for estimating a rotor position may include a synchronous machine, including at least one stator winding pair configured to create a magnetic field when an input voltage is applied and a rotor having a field winding and configured to rotate within the magnetic field created by the at least one stator winding pair. The system may include a phase detector configured to determine a phase difference between the input voltage and a field voltage induced in the field winding of the rotor. The system may also include a processor configured to receive a signal from the phase detector indicative of the phase difference between the input voltage and the field voltage, and to estimate the rotor position based on the phase difference.