Abstract: An electrical system for an aircraft with an electric taxi system (ETS), the electrical system may include at least one traction motor, a DC link and at least one traction-motor bidirectional DC-AC converter interposed between the at least one traction motor and the DC link. An engine-driven power source may be configured to provide DC power to the DC link or extract DC power from the DC link. A battery unit may be configured to provide DC power to the DC link or extract DC power from the DC link. An adaptive power controller may be interconnected with the power source, the battery unit and the at least one traction-motor bidirectional DC-AC converter and configured to regulate voltage of DC power delivered to the DC link.

Abstract: A gate departure system for an aircraft includes an electric traction motor for driving a wheel of a main landing gear assembly of the aircraft on only one side of the aircraft; and a controller selectively connected to a starter-generator of an auxiliary power unit (APU) and to the traction motor to control flow of electrical power to either the starter-generator for starting of the APU or the electric traction motor for driving the wheel.

Abstract: A gate departure system for an aircraft includes an electric traction motor for driving a wheel of a main landing gear assembly of the aircraft on only one side of the aircraft; and a controller selectively connected to a starter-generator of an auxiliary power unit (APU) and to the traction motor to control flow of electrical power to either the starter-generator for starting of the APU or the electric traction motor for driving the wheel.

Abstract: An electrical system for an aircraft with an electric taxi system (ETS), the electrical system may include at least one traction motor, a DC link and at least one traction-motor bidirectional DC-AC converter interposed between the at least one traction motor and the DC link. An engine-driven power source may be configured to provide DC power to the DC link or extract DC power from the DC link. A battery unit may be configured to provide DC power to the DC link or extract DC power from the DC link. An adaptive power controller may be interconnected with the power source, the battery unit and the at least one traction-motor bidirectional DC-AC converter and configured to regulate voltage of DC power delivered to the DC link.

Abstract: A deadtime optimization apparatus and method may determine when it is safe to turn a switch ON, eliminating the need to have a switch controller purposely insert a deadtime period in the algorithm (i.e., it can go back to producing ideal PWM). Since the decision of when it is safe to turn ON the switch may be achieved through measurement, it is expected that the length of time may change for each pulse as the operating conditions change. Therefore, the apparatus and methods of the present invention may take on a dynamic characteristic because the safe to turn ON (STTO) time may vary for each pulse.

Abstract: A deadtime optimization apparatus and method may determine when it is safe to turn a switch ON, eliminating the need to have a switch controller purposely insert a deadtime period in the algorithm (i.e., it can go back to producing ideal PWM). Since the decision of when it is safe to turn ON the switch may be achieved through measurement, it is expected that the length of time may change for each pulse as the operating conditions change. Therefore, the apparatus and methods of the present invention may take on a dynamic characteristic because the safe to turn ON (STTO) time may vary for each pulse.

Abstract: A starting system for aircraft engines employs power from multiple power sources. Each engine is started with a starter motor that is driven by the same multiple power sources which collectively provide starting power. As engine speed increases during each starting cycle a voltage boost is progressively provided by a boost converter. The starting system allows use of voltages higher than output voltage of the power sources while allowing the power sources to remain connected to a main aircraft power distribution bus.

Abstract: A bi-directional dc-dc converter is provided that may provide voltage conversion for two separate electrical power systems. The two electrical power systems may have different functions, electrical requirements and power transfer directions. The bi-directional dc-dc converter may include back-to-back bi-directional dc-dc converter circuits isolated from each other by a transformer. Multiple such dc-dc converters may be connected in parallel to increase power capability. Phase shift pulse width modulation (PWM) may be used to switch the parallel dc-dc converters so as to decrease both voltage ripple and current ripple. The number of dc-dc converters may be modified to meet the different needs of various electric power systems. A single bi-directional dc-dc converter of the invention may be employed to provide electric power conversion for multiple electric power systems, even where those systems have different power requirements and different power transfer directions.

Abstract: A starting system for aircraft engines employs power from multiple power sources. Each engine is started with a starter motor that is driven by the same multiple power sources which collectively provide starting power. As engine speed increases during each starting cycle a voltage boost is progressively provided by a boost converter. The starting system allows use of voltages higher than output voltage of the power sources while allowing the power sources to remain connected to a main aircraft power distribution bus.

Abstract: A bi-directional dc-dc converter is provided that may provide voltage conversion for two separate electrical power systems. The two electrical power systems may have different functions, electrical requirements and power transfer directions. The bi-directional dc-dc converter may include back-to-back bi-directional dc-dc converter circuits isolated from each other by a transformer. Multiple such dc-dc converters may be connected in parallel to increase power capability. Phase shift pulse width modulation (PWM) may be used to switch the parallel dc-dc converters so as to decrease both voltage ripple and current ripple. The number of dc-dc converters may be modified to meet the different needs of various electric power systems. A single bi-directional dc-dc converter of the invention may be employed to provide electric power conversion for multiple electric power systems, even where those systems have different power requirements and different power transfer directions.

Abstract: When multiple motors (40) share a common DC power supply (10) via a bus (20), a system and method is provided for managing the effect of regenerative energy caused by a motor. The regenerative energy may be sensed, e.g., by a power electronics controller (50, 50?). In response, one or more of the other motors currently in operation may be controlled to operate according to a reduced power factor. Thus, the excess energy is consumed without adding any new components or increasing the amount of work performed in the system.

Abstract: A circuit producing power with controlled frequency from a variable frequency power source (14) includes an AC bus (20) connected to the variable frequency power source (14) and a plurality of load circuits, each load circuit including an AC input (24) and an AC output (26), an AC contactor (30) between the input (24) and output (26), a rectifier (32) between the AC contactor (30) and the output (26) and an inverter (34) between the rectifier (32) and the output (26). A method of producing power with controlled frequency is also disclosed.

Abstract: When multiple motors (40) share a common DC power supply (10) via a bus (20), a system and method is provided for managing the effect of regenerative energy caused by a motor. The regenerative energy may be sensed, e.g., by a power electronics controller (50, 50?). In response, one or more of the other motors currently in operation may be controlled to operate according to a reduced power factor. Thus, the excess energy is consumed without adding any new components or increasing the amount of work performed in the system.

Abstract: An adaptive, sensorless position sensing apparatus (250) derives rotor position of a synchronous machine (200). The apparatus (250) comprises a first rotor position deriving unit (300) for generating first rotor position values by applying a first sensorless rotor position calculation technique, which emulates a resolver; a second rotor position deriving unit (400) for generating second rotor position values by applying a second sensorless rotor position calculation technique; and a rotor position result output unit (450) for outputting rotor position results over a range of rotor speeds as a function of the first rotor position values, the second rotor position values, and rotor speed.

Abstract: A circuit producing power with controlled frequency from a variable frequency power source (14) includes an AC bus (20) connected to the variable frequency power source (14) and a plurality of load circuits, each load circuit including an AC input (24) and an AC output (26), an AC contactor (30) between the input (24) and output (26), a rectifier (32) between the AC contactor (30) and the output (26) and an inverter (34) between the rectifier (32) and the output (26). A method of producing power with controlled frequency is also disclosed.

Abstract: A position sensing apparatus (300) derives rotor position of a synchronous machine (200) from signals output from the machine (200). In one embodiment, the position sensing apparatus (300) comprises: a bandpass filter (322) that filters phase voltage signals output from main stator windings (216) of the synchronous machine (200) during AC excitation, thereby extracting a rotor position-indicating component from the phase voltage signals; a converter (324) that converts the filtered phase voltages into balanced two-phase quadrature signals, the balanced two-phase quadrature signals indicating positioning of the rotor (212); and an excitation controller (204) for controlling AC excitation frequency as a function of rotor speed.

Abstract: An adaptive, sensorless position sensing apparatus (250) derives rotor position of a synchronous machine (200). The apparatus (250) comprises a first rotor position deriving unit (300) for generating first rotor position values by applying a first sensorless rotor position calculation technique, which emulates a resolver; a second rotor position deriving unit (400) for generating second rotor position values by applying a second sensorless rotor position calculation technique; and a rotor position result output unit (450) for outputting rotor position results over a range of rotor speeds as a function of the first rotor position values, the second rotor position values, and rotor speed.

Abstract: A position sensing apparatus (300) derives rotor position of a synchronous machine (200) from signals output from the machine (200). In one embodiment, the position sensing apparatus (300) comprises: a bandpass filter (322) that filters phase voltage signals output from main stator windings (216) of the synchronous machine (200) during AC excitation, thereby extracting a rotor position-indicating component from the phase voltage signals; a converter (324) that converts the filtered phase voltages into balanced two-phase quadrature signals, the balanced two-phase quadrature signals indicating positioning of the rotor (212); and an excitation controller (204) for controlling AC excitation frequency as a function of rotor speed.

Abstract: A rotating electrical machine, such as an aircraft starter-generator, includes an exciter that has its stator windings divided into a number of sections. A plurality of switches are electrically coupled to the exciter stator winding sections and are configured and controlled so that the exciter stator winding sections may be selectively coupled in series or in parallel with one another, and selectively coupled to receive either DC or AC power.

Abstract: A position sensor emulator system and method for use in the control of synchronous machines are disclosed. The position sensor emulator system (220) includes a first bandpass filter (222) that filters phase voltage signals from a stator of a synchronous machine (230). A converter (224) that converts the filtered phase voltages into balanced two-phase quadrature signals. A rectifier (226) that rectifies exciter voltage signals of the synchronous machine (230) and a second bandpass filter (228) that filters the rectified exciter voltage signals to generate a reference signal.