Abstract: A generator system includes a generator and a generator control unit (GCU). The GCU is connected to monitor and regulate the generator output voltage. The GCU includes a protection signal processor that receives monitored generator voltages and executes software to detect an overvoltage condition. The GCU further includes redundant, hardware based overvoltage detection that detects a peak voltage value associated with the monitored generator voltage and includes a fast overvoltage detection circuit that generates a first overvoltage fault signal if the peak voltage value is greater than a first threshold value and includes an inverse overvoltage detection circuit that generates a second overvoltage fault signal if the peak voltage value is greater than a second threshold value for a duration of time that varies with a magnitude of the peak voltage value.

Abstract: A generator system includes a generator and a generator control unit (GCU). The GCU is connected to monitor and regulate the generator output voltage. The GCU includes a protection signal processor that receives monitored generator voltages and executes software to detect an overvoltage condition. The GCU further includes redundant, hardware based overvoltage detection that detects a peak voltage value associated with the monitored generator voltage and includes a fast overvoltage detection circuit that generates a first overvoltage fault signal if the peak voltage value is greater than a first threshold value and includes an inverse overvoltage detection circuit that generates a second overvoltage fault signal if the peak voltage value is greater than a second threshold value for a duration of time that varies with a magnitude of the peak voltage value.

Abstract: A generator controller provides independent and redundant overvoltage protection to an associated generator. The generator controller monitors the generator output at a first point of a regulation and a second point of regulation. A generator control unit (GCU) provides overvoltage protection based on the generator output monitored at the first point of regulation, including at least one of tripping a first generator control relay (GCR) to remove excitation from an exciter winding and tripping a generator line contactor (GLC) to disconnect the generator output from a bus. A overvoltage protection unit (OPU) provides independent, redundant protection based on the generator output monitored at the second point of regulation, including at least one of tripping a second GCR to remove excitation from the exciter winding and tripping the GLC to disconnect the generator output from the bus.

Abstract: A generator controller provides independent and redundant overvoltage protection to an associated generator. The generator controller monitors the generator output at a first point of a regulation and a second point of regulation. A generator control unit (GCU) provides overvoltage protection based on the generator output monitored at the first point of regulation, including at least one of tripping a first generator control relay (GCR) to remove excitation from an exciter winding and tripping a generator line contactor (GLC) to disconnect the generator output from a bus. A overvoltage protection unit (OPU) provides independent, redundant protection based on the generator output monitored at the second point of regulation, including at least one of tripping a second GCR to remove excitation from the exciter winding and tripping the GLC to disconnect the generator output from the bus.

Abstract: An intermediate product is provided and includes a substrate having at least one thick-film circuit formed thereon. An outer surface of a first portion of the thick-film circuit is coated with a readily removable protective material such as ethyl cellulose to protect the first portion from hot-slag substrate material generated during a laser scribing operation. The substrate also includes at least one uncoated portion which can be laser scribed for separation of the thick-film circuit from the remainder of the substrate. After laster scribing, the protective material is removed to permit visual inspection of the thick-film circuit.

Abstract: A method is provided for forming a thick-film circuit having at least one thick-film resistor element upon a substrate and laser scribing the substrate to remove the circuit from the remaining portion of the substrate. A thick-film circuit comprising conductor lines and at least one resistor element is first printed upon a substrate. Thereafter, the resistor element may be laser trimmed to increase the resistance value thereof. After laser trimming, a protective material such as ethyl cellulose is coated onto the outer surface of the resistor element to protect it from hot-slag ceramic material generated during a laser scribing operation. The substrate is then topside laser scribed to separate the thick-film circuit from the remaining portion of the substrate. Following laser scribing, the protective material is removed by washing the resistor element with a solvent.

Abstract: A smooth resistance characteristic, a reduction in component cost, and high durability are achieved for a variable resistor card formed using thick-film silk screen deposition. An arcuate wiper track and radial extension areas are all formed of a resistance material deposited using silk screen techniques. Laser trimming of the extension areas provides a desired characteristic of resistance versus sweep angle for the variable resistor. The resistance characteristic is continuous and nonstepped, thereby avoiding the creation of spikes caused by small circuit breaks during sweeping movement of the wiper contact.