A resolver interface system for a motor drive system includes a phase detector configured to be operatively connected to a rotation signal output of a resolver to receive a rotation signal therefrom and generate a phase difference signal. A differentiator is operatively connected to an output of the phase detector to convert the phase difference signal of the phase detector into a pulse output configured to be read by a processing system.

A method for operating a lift system includes a lift cage movably housed movably inside a lift shaft. A linear drive is configured to drive the lift cage, the linear drive includes a stator arrangement fixedly attached to the lift shaft with a plurality of stators and a rotor attached to the lift cage. The stator arrangement includes electromagnetic coils, each of the coils configured to be operated by one phase of a polyphase alternating current. The method includes providing the polyphase alternating current to operate the stator arrangement and thereby drive the lift cage to generate an upward force for the lift cage, monitoring a deceleration value of the lift system with sensors that are permanently installed in the lift shaft, and switching the linear drive into a safety operating state when the deceleration value above a predefined threshold value is determined by way of said monitoring.