Abstract: A method for pulse width modulated pulse synchronization in a parallel UPS system uses the locally measured critical bus voltage to detect a zero crossing and adjust the PWM pulse to coincide with the zero crossing. No communication between the units is required to perform synchronization, and no “master” and “slave” relationship exists to thereby increase the total system reliability.

Abstract: A serial communications bus is utilized to send key action data between parallel UPS units. The communications bus is used to transmit data at the zero crossing of the critical bus voltage. Each UPS unit then takes action based upon the event data received at the next zero crossing of the critical bus voltage.

Abstract: A method for pulse width modulated pulse synchronization in a parallel UPS system uses the locally measured critical bus voltage to detect a zero crossing and adjust the PWM pulse to coincide with the zero crossing. No communication between the units is required to perform synchronization, and no “master” and “slave” relationship exists to thereby increase the total system reliability.

Abstract: An uninterruptible power supply is disclosed that includes a digital controller comprising a plurality of microprocessors. These microprocessors are programmed and arranged to provide various control features heretofore unavailable using analog controllers of the prior art.

Abstract: An uninterruptible power supply is disclosed that includes a digital controller comprising a plurality of microprocessors. These microprocessors are programmed and arranged to provide various control features heretofore unavailable using analog controllers of the prior art.

Abstract: A damper for damping movement of a shaft, the damper including a housing having an inner surface defining a chamber and a rotor rotatably mounted in the chamber. The chamber is filled with magnetorheological fluid such that when the rotor is moved in the chamber the magnetorheological fluid damps the movement of the rotor. The rotor has an outer surface adjacent to and spaced apart from the inner surface. The damper further comprises shaft coupled to the rotor and an outer magnet adjacent the space between the outer surface and the inner surface for restricting the flow of the magnetorheological fluid in the space between the outer surface and the inner surface.

Abstract: An electric caliper for a brake system includes a cylindrical housing having a bore, a bridge extending from the housing, and a pair of friction elements operatively disposed under the bridge. The electric caliper also includes a motor disposed within the bore and a planetary gear system disposed within the bore and operatively connected to the motor. The electric caliper further includes a ball screw disposed within the bore and positioned around the motor and operatively connected to the planetary gear system. The electric caliper includes a piston operatively connected to the ball screw. Displacement of the piston causes the friction elements to operatively engage a disc disposed between the friction elements.

Abstract: A method for monitoring motor position in a multiple phase switched reluctance motor having phase windings which are energized by a controller involves producing a signal indicative of a current delivered to an active phase winding and producing a signal indicative of a voltage across the active phase winding. A flux linkage associated with the active phase winding is then established based at least in part upon the current indicative signal and the voltage indicative signal. A position of the motor is then estimated based at least in part upon the current indicative signal and the established flux linkage.