Patent ID: 7609534

Claim:
A device for providing power to an elevator machine, comprising a converter interface configured to be between a power source and an elevator machine controller, the converter interface providing an output current to the controller, the converter interface comprising: a phase locked loop portion having three phase inputs, all three of the phase inputs being coupled to a lead of three phase input power if three phase input power is available from the power source, one of the phase inputs being set at zero and two others of the three phase inputs each being coupled to a lead of single phase input power if only single phase input is available from the power source, the phase locked loop portion using an estimated direct component and an estimated quadrature component based on the single phase input power when the single phase input power is available, the estimated direct component comprising a measured voltage of the single phase power; a proportional integral regulator that provides an indication of a current for eliminating error between a desired current level provided to the controller and an output current level from the converter interface; and a current regulator portion that uses (i) an output from the phase locked loop portion combined with an output from the proportional integral regulator and (ii) the estimated direct component as a feed-forward input, the current regulator portion allowing the converter interface to provide three phase output power to the elevator machine controller if either the three phase input power or the single phase input power is available.