Abstract: A power supply system includes first and second generators that are measured by first and second current sensors. The system also includes a first generator controller configured to: receive a first current signal from the first current sensing device and a second current signal from the second current sensing device; analyze the first current signal and the second current signal to determine a first voltage foldback value based on a first common mode current calculated from the first current signal and the second current signal; and operate the first DC power supply to reduce a first voltage output of the first DC power supply by the first voltage foldback value.

Abstract: A power supply system includes first and second generators that are measured by first and second current sensors. The system also includes a first generator controller configured to: receive a first current signal from the first current sensing device and a second current signal from the second current sensing device; analyze the first current signal and the second current signal to determine a first voltage foldback value based on a first common mode current calculated from the first current signal and the second current signal; and operate the first DC power supply to reduce a first voltage output of the first DC power supply by the first voltage foldback value.

Abstract: A system includes a two-switch H-bridge topology, which has a first switch with a first gate drive connected to control on and off states of the first switch. A second switch has a second gate drive connected to control on and off states of the second switch. An exciter winding is connected from a first node between the first switch and a second flyback diode to a second node between a first flyback diode and the second switch. A controller is connected to control the first gate drive and the second gate drive in a mode wherein the first switch is always on while the second cycles as a duty-cycle-controlled switch element for the exciter winding.

Abstract: System and methods for passive power sharing of parallel sources are provided. Aspects include a first DC power supply including a first generator and a rectifier circuit, a second DC power supply including a second generator and a second rectifier, wherein a first output of the first DC power supply and a second output of the second DC power supply are commonly coupled at a common bus point, a first current sensing device coupled between the first output of the first DC power supply and the common bus point, a first generator controller configured to receive a first current signal from the first current sensing device, analyze the first current signal to determine a first voltage droop value based on the first current signal, and operate the first DC power supply to reduce a first voltage output of the first DC power supply by the first voltage droop value.

Abstract: In accordance with at least one aspect of this disclosure, a method can include measuring a voltage across a DC link of a generator system when a generator exciter is inactive and a generator permanent magnet is active, and detecting a short or open permanent magnet generator (SOPMG) fault condition in the generator system with a DC link monitor operatively connected to measure the voltage across the DC link.

Abstract: A method and controller for controlling a Wound Field Synchronous Machine (WFSM) of an electric power generation system (EPGS) having a field winding and a stator armature winding is provided. The controller includes an adjustable component coupled to the generator and a power factor controller for adjusting the adjustable component to lower the power factor of the WFSM as a function of power output to a load of the EPGS to stabilize a current in the field winding.

Abstract: A high voltage DC (HVDC) system can include a generator configured to output alternating current (AC), a rectifier connected to the generator via AC phase lines, the rectifier configured to convert the AC to DC to output the DC to DC feeder lines, and a crowbar system. The crowbar system can include a switch module operatively connected to the AC phase lines to prevent AC from flowing to the rectifier in a cutoff state. The crowbar system can be configured to determine whether at least one cutoff condition exists. The at least one cutoff condition can be or include one or more of a DC overcurrent downstream of the rectifier, a DC overvoltage downstream of the rectifier, an AC overcurrent from the generator, or an arc fault. The crowbar system can be configured to control the switch module to the cutoff state if the at least one cutoff condition exists.

Abstract: In accordance with at least one aspect of this disclosure, a method can include measuring a voltage across a DC link of a generator system when a generator exciter is inactive and a generator permanent magnet is active, and detecting a short or open permanent magnet generator (SOPMG) fault condition in the generator system with a DC link monitor operatively connected to measure the voltage across the DC link.

Abstract: A method includes detecting an initial fault in a system and opening a contactor to isolate a load bus from the system for a window of time. During the window of time, the method includes detecting whether current flows from a generator of the system. If current flows from the generator of the system during the window of time, the method includes isolating the load bus from the generator. If current does not flow from the generator to the system during the window of time, the method includes isolating the load bus from all sources including the generator.

Abstract: System and methods for passive power sharing of parallel sources are provided. Aspects include a first DC power supply including a first generator and a rectifier circuit, a second DC power supply including a second generator and a second rectifier, wherein a first output of the first DC power supply and a second output of the second DC power supply are commonly coupled at a common bus point, a first current sensing device coupled between the first output of the first DC power supply and the common bus point, a first generator controller configured to receive a first current signal from the first current sensing device, analyze the first current signal to determine a first voltage droop value based on the first current signal, and operate the first DC power supply to reduce a first voltage output of the first DC power supply by the first voltage droop value.

Abstract: An assembly according to an embodiment of the present disclosure includes, among other things, a synchronous machine including a rotating portion and a stationary portion, the rotating portion including at least one rotating diode coupled to a field winding, and the stationary portion including a stator winding and an exciter winding. A control unit includes a first gate and a second gate. The exciter winding is connected in series to the first gate and the second gate during a first operating mode to energize the exciter winding. The exciter winding is electrically connected in series to a first gate but is electrically disconnected from the second gate in a second, different operating mode to electrically disconnect the exciter winding from an exciter energy source. A method of operating a synchronous machine is also disclosed.

Abstract: In accordance with one or more embodiments, a system is provided. The system includes feeders, sensors, and a controller. The feeders connect a panel to a generator and a load. The sensors are on the feeders. The controller receives sensor signals from the sensors. The controller evaluates the sensor signals to determine a fault location.

Abstract: A method includes detecting an initial fault in a system and opening a contactor to isolate a load bus from the system for a window of time. During the window of time, the method includes detecting whether current flows from a generator of the system. If current flows from the generator of the system during the window of time, the method includes isolating the load bus from the generator. If current does not flow from the generator to the system during the window of time, the method includes isolating the load bus from all sources including the generator.

Abstract: In accordance with one or more embodiments, a system is provided. The system includes feeders, sensors, and a controller. The feeders connect a panel to a generator and a load. The sensors are on the feeders. The controller receives sensor signals from the sensors. The controller evaluates the sensor signals to determine a fault location.

Abstract: A method and controller for controlling a Wound Field Synchronous Machine (WFSM) of an electric power generation system (EPGS) having a field winding and a stator armature winding is provided. The controller includes an adjustable component coupled to the generator and a power factor controller for adjusting the adjustable component to lower the power factor of the WFSM as a function of power output to a load of the EPGS to stabilize a current in the field winding.

Abstract: An assembly according to an embodiment of the present disclosure includes, among other things, a synchronous machine including a rotating portion and a stationary portion, the rotating portion including at least one rotating diode coupled to a field winding, and the stationary portion including a stator winding and an exciter winding. A control unit includes a first gate and a second gate. The exciter winding is connected in series to the first gate and the second gate during a first operating mode to energize the exciter winding. The exciter winding is electrically connected in series to a first gate but is electrically disconnected from the second gate in a second, different operating mode to electrically disconnect the exciter winding from an exciter energy source. A method of operating a synchronous machine is also disclosed.

Abstract: An assembly according to an embodiment of the present disclosure includes, among other things, a synchronous machine including a rotating portion and a stationary portion, the rotating portion including at least one rotating diode coupled to a field winding, and the stationary portion including a stator winding and an exciter winding. A control unit includes a first gate and a second gate. The exciter winding is connected in series to the first gate and the second gate during a first operating mode to energize the exciter winding. The exciter winding is electrically connected in series to a first gate but is electrically disconnected from the second gate in a second, different operating mode to electrically disconnect the exciter winding from an exciter energy source. A method of operating a synchronous machine is also disclosed.

Abstract: An aircraft main power generation system includes a rotor shaft, a main power generator a permanent magnet, an exciter, an aircraft power bus, and a generator control unit. The generator control unit is configured to provide a control current to the exciter in response to a speed of the main power generator reaching a threshold speed and electrically couple the main power generator to the aircraft power bus in response to the speed of the main power generator reaching a minimum operating speed, the threshold speed being lower than the minimum operating speed; or provide a control current to the exciter in response to the speed of the main power generator reaching a predetermined speed and electrically coupling the main power generator to the aircraft power bus in response to a time period elapsing after the speed of the main power generator has reached the predetermined speed.

Abstract: An aircraft main power generation system includes a rotor shaft, a main power generator a permanent magnet, an exciter, an aircraft power bus, and a generator control unit. The generator control unit is configured to provide a control current to the exciter in response to a speed of the main power generator reaching a threshold speed and electrically couple the main power generator to the aircraft power bus in response to the speed of the main power generator reaching a minimum operating speed, the threshold speed being lower than the minimum operating speed; or provide a control current to the exciter in response to the speed of the main power generator reaching a predetermined speed and electrically coupling the main power generator to the aircraft power bus in response to a time period elapsing after the speed of the main power generator has reached the predetermined speed.

Abstract: An assembly according to an embodiment of the present disclosure includes, among other things, a synchronous machine including a rotating portion and a stationary portion, the rotating portion including at least one rotating diode coupled to a field winding, and the stationary portion including a stator winding and an exciter winding. A control unit includes a first gate and a second gate. The exciter winding is connected in series to the first gate and the second gate during a first operating mode to energize the exciter winding. The exciter winding is electrically connected in series to a first gate but is electrically disconnected from the second gate in a second, different operating mode to electrically disconnect the exciter winding from an exciter energy source. A method of operating a synchronous machine is also disclosed.