Abstract: A direct current (DC) overvoltage monitoring and protection device includes an overvoltage sensor operably connected to an electrical power input line. The overvoltage sensor is configured to change state upon detection of a voltage over a preselected threshold. An overvoltage relay is operably connected to the overvoltage sensor. The overvoltage relay includes one or more relay switches configured to move between a first position and a second position when the voltage over the preselected threshold is detected. An independent relay power source is operably connected to the overvoltage relay to provide electrical power to the overvoltage relay, separate from the electrical power being monitored via the electrical power input line.

Abstract: A direct current (DC) overvoltage monitoring and protection device includes an overvoltage sensor operably connected to an electrical power input line. The overvoltage sensor is configured to change state upon detection of a voltage over a preselected threshold. An overvoltage relay is operably connected to the overvoltage sensor. The overvoltage relay includes one or more relay switches configured to move between a first position and a second position when the voltage over the preselected threshold is detected. An independent relay power source is operably connected to the overvoltage relay to provide electrical power to the overvoltage relay, separate from the electrical power being monitored via the electrical power input line.

Abstract: Apparatus for detecting an operating condition of a machine synchronizes sampling instants with the machine condition so that high reliability data are obtained. More particularly, an indication of the operating condition of a rotor of the machine is developed at each sampling instant. The operating condition may be, for example, the position of the rotor, in which case estimates of the rotor position and rotor velocity at each of the sampling instants are developed. Sampling signals are then derived from the rotor position and velocity estimates to synchronize the sampling instants to the rotor position.

Abstract: A sensorless control for operating an inverter coupled to a switched reluctance machine includes an instantaneous position generation circuit that develops a signal for controlling commutation of the switched reluctance machine. The instantaneous position generation circuit includes a digitally controlled counter which provides a direct interface between a position estimation circuit and commutation logic for the inverter.

Abstract: A control for operating an inverter coupled to a switched reluctance machine includes a relative angle estimation circuit for estimating rotor angle for a phase in the switched reluctance machine. The relative angle estimation circuit estimates a phase voltage and thereby calculates phase flux linkage to estimate the rotor angle.

Abstract: An apparatus for estimating rotor position of a rotating machine having an even number of phase windings selects first and second phase position estimates developed in response to pulses applied to phase windings having associated phase profiles that are displaced at other than 180 electrical degrees and determines a rotor position estimate from the first and second phase position estimates.

Abstract: An estimator initialization circuit for a sensorless switched reluctance machine system pulses phase windings of the machine a certain number of times and derives initial values for an estimator of the system.