Hamilton Sundstrand Corporation

Sundstrand Corporation

William S Heglund

Michael C Harke

Matthew L Wilhide

Gregory I Rozman

Glenn C Lemmers, Jr

John F Defenbaugh

Shan-Chin Tsai

Thomas P Joyce

Lon R Hoegberg

Madan L Bansal

Stephen R Jones

Caio A Ferreira

Mario R Rinaldi

An example electrical power system includes a bus current controller configured to adjust a direct current (DC) provided on a DC bus, and a plurality of energy storage modules (ESMs). Each ESM includes at least one energy storage device, and includes a DC/DC converter configured to control charging of the at least one energy storage device from the DC bus and discharging of the at least one energy storage device onto the DC bus. A shared system controller is configured to control the bus current controller and the plurality of DC/DC converters. A method of controlling an electrical power system is also disclosed.

Electrical power system including energy storage modules and shared system controller

A power supply system to provide power to a load connected between first and second connectors. The system includes a generator that produces an alternating current generator output and a rectifier that receives the alternating current generator output and converts it into a direct current output and provides the direct current (DC) output between the first and second connectors. The system also includes a filter connected to the rectifier and between the connectors and that smooths the DC output. The filter includes a midpoint configured to be connected to ground. The system also includes a fault clearing source connected to the first connector that provides a clearing voltage to the first connector when a ground fault occurs on the first connector.

Fault clearing in midpoint grounded systems

A generator system can include a first generator, a first controller operatively connected to the first generator to control a first generator voltage output, a second generator, and a second controller operatively connected to the second generator to control a second generator voltage output. The first generator and the second generator can be configured in a parallel generator configuration to share load power. The first controller and the second controller can be configured to provide foldback control. The first controller and the second controller can be configured to calibrate foldback to correct for current sharing imbalance between the first generator and the second generator.

Parallel generator systems and controllers therefor

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.

Passive power sharing of paralleled sources

Systems for power sharing coordination of parallel sources are provided. Aspects include a first DC power supply, a second DC power supply, a first generator controller configured to operate the first DC power source, a first current sensing device coupled between the first DC power supply and the common bus point, a second current sensing device coupled between the common bus point and a load, wherein the first generator controller is configured to receive a first current signal from the first current sensing device, receive a second current signal from the second current sensing device, determine a load share percentage for the first DC power supply, determine a first voltage adjustment based on the first current signal, the second current signal, and the load share percentage, and operate the first DC power supply to adjust a first voltage output by the first voltage adjustment.

Power sharing coordination of paralleled sources

Embodiments include systems, methods, and devices for voltage regulation of a hybrid energy storage module (HESM). The embodiments include a system controller including a first voltage regulator and a second voltage regulator, a first HESM coupled to the system controller, where the first HESM is coupled to a first bus, and a second HESM coupled to the system controller, where the second HESM is coupled to a second bus, and the first bus and the second bus are different.

Hybrid energy storage module voltage regulation

An electrical power system for an aircraft may comprise a hybrid energy storage system, a first high voltage bus coupled to an input of said hybrid energy storage system, a second high voltage bus coupled to an output of said hybrid energy storage system, and a directed energy system coupled to the second high voltage bus. The hybrid energy storage system receives DC power via the input from said first high voltage bus, converts the DC power to a converted DC power, and dynamically stores the converted DC power and/or provides said converted DC power via said output to said directed energy system via the second high voltage bus.

Hybrid energy storage modules for directed energy systems

A transmission for providing mechanical power from an input includes a transmission assembly having an arm configured and adapted to be connected to a mechanical input for rotation at an input speed. A first planet is rotatably mounted to a first end of the arm. A trim ring operatively contacts the first planet for mutual rotation therewith. A brake is operatively connected to the trim ring for controlling rotation of the trim ring. A second planet is rotatably mounted to a second end of the arm. The second planet operatively contacts the first planet for mutual rotation therewith. An output ring operatively contacts the second planet for mutual rotation therewith to rotate at an output speed based on an input speed of the arm and a trim speed of the trim ring.

Control of shifting transmission for constant and variable frequency systems

A control for operating an inverter coupled to a switched reluctance machine is responsive to the magnitudes of current flowing in the phase windings of the machines and controls switches in legs of the inverter based upon such magnitude.

Commutation apparatus and method for a four state sensorless switched reluctance machine system utilizing machine winding current sensing

An electric power starter/generator system for converting electrical energy from a remote dc electrical power source coupled to a dc distribution bus to mechanical energy to start a turbine engine in a start mode, and for converting mechanical energy from the turbine engine to electrical energy to power utilization equipment connected to the dc bus in a generate mode, comprises a switched reluctance machine, an inverter having a dc input/output coupled to the dc distribution bus, and at least a first and a second switch coupling each of the machine's phase windings to the dc bus, and at least a first and a second diode for cross-cupling each of said phase windings to the dc bus, and a controller coupled to the inverter for monitoring and controlling system performance during the start mode and the generate mode of system operation. The controller monitors rotor position and generates switching control signals to enable the switches for each of the phase windings at a fixed angle prior to alignment of the rotor pole with the associated stator pole, coupling the phase winding to the dc bus and allowing dc phase current to flow to energize the winding. The controller further generates switching control signals to disable the switches at a fixed angle after alignment, decoupling the phase winding from the dc bus and forcing dc current flow back through the diodes to allow the switched reluctance machine to operate as a generator. During this mode, the controller monitors phase current and dc bus voltage, calculates a maximum phase current limit and a minimum phase current limit, and modulates the switches to regulate the dc phase current within these limits. In this way, the controller maintains the dc bus voltage at a desired level regardless of system load. The controller also allows operation in a start mode.

Switched reluctance starter/generator system and method of controlling

A method of linearizing the output performance of a switched reluctance generator, comprises the steps of exciting the switched reluctance generator during a first phase of operation at a turn-on angle which need not be accurately calculated to produce the desired excitation current. Next, during a second phase of commutation, the switched reluctance generator is freewheeled when a phase current of the switched reluctance generator exceeds a first calculated current level. This freewheeling continues until the phase current of the switched reluctance generator exceeds a second calculated current level, at which point the switched reluctance generator enters the generation phase of its commutation cycle. The linearization of the performance occurs because the first and second calculated current levels are calculated as a function of energy converted per electrical cycle. This function of energy converted per electrical cycle is calculated using an inductance of the switched reluctance generator in an aligned position and an inductance of the switched reluctance generator in an unaligned position. The shape of a graph of the flux linkage versus the phase current is controlled through the selection of the first and second calculated current levels which increases efficiency while linearizing the performance of the switched reluctance generator. The area enclosed by this graph is equal to the energy converted per electrical cycle.

Method of linearizing the performance of switched reluctance generators

A method of commutation of a switched reluctance machine to allow operation in a generate mode comprises the steps of closing upper and lower switches coupling a stator winding to a power bus during an increase in the inductance of a stator winding to allow a flow of current from the power bus through the winding, opening one of the upper and lower switches when the current reaches a first predetermined value, opening the closed of the upper and lower switches during a decrease in the inductance of a stator winding, and closing one of the upper and lower switches during a period of non-alignment of the rotor and stator pole. The method further includes the step of closing both the upper and lower switches if the monitored current falls below a second predetermined value. In this way, the current through the stator winding is not allowed to decay to zero.

Output overload and fault tolerant commutation method for a switched

The present invention provides for detecting rotor speed through the use of sense coils on the stator teeth. Voltage ripples caused by the rotor slots is detected by combining the signals of several such sense coils so that the fundamental voltage signal is cancelled or rejected and only the ripple voltages remain, a signal proportional to rotor speed. Several alternative methods for implementing that technique are discussed herein. At low induction motor speeds, the present invention filters out the voltage ripples and incident third harmonics and instead estimates rotor speed from the fundamental voltage. When the induction motor is already being driven by a prime mover, the present invention selects a proper initial frequency command for initial motor start by identifying rotor speed from the PWM inverter. Further, the present invention provides for using a generator to control voltage to the induction motor, with a PWM inverter to control frequency signals to the induction motor.

Growing community of inventors

Rockford, IL, United States of America

William S Heglund