Abstract: A method and apparatus for providing a source of power, comprising: a solid oxide fuel cell system and a thermionic device. The solid oxide fuel cell system provides a first source of power, wherein the solid oxide fuel cell system produces heat waste when the solid oxide fuel cell is providing the first source of power. The thermionic device for provides a second source of power, the thermionic device provides the second source of power from the heat waste which is provided to said thermionic device and an exhaust conduit provides fluid communication between an exhaust of the fuel cell system and a heat exchanger of the thermionic device.

Abstract: A method and apparatus for providing a source of power, comprising: a solid oxide fuel cell system and a thermo photovoltaic device. The solid oxide fuel cell system provides a first source of power, wherein the solid oxide fuel cell system produces heat waste when the solid oxide fuel cell is providing the first source of power. The thermo photovoltaic device provides a second source of power and the thermo photovoltaic device provides the second source of power from the heat waste of the solid oxide fuel cell system which is further heated by a combustor in order to provide the second source of power.

Abstract: A power system used for transferring power between a plurality of power sources is provided. A power system according to the present invention is comprised of a plurality of power sources, wherein each source includes a pair of terminals. The power system is further comprised of a power converter, including a pair of switches for each one of the plurality of power sources. Each of these switches are connected to the respective pairs of terminals for each source. Each switch further includes an associated diode, and each switch pair includes a common node. The power converter further includes a plurality of inductors numbering one less than the number of power sources, wherein each inductor is connected across two of the common nodes. The power converter further includes a control unit configured to actuate the switches in accordance with, and to carry out, one of a plurality of modes of operation.

Abstract: A solid-oxide fuel cell system having a relatively large primary fuel cell sub-assembly for steady-state operation and a relatively small secondary fuel cell sub-assembly which is rapidly heatable to a threshold operating temperature to a) produce usable power in a short time period, b) cascade a hot exhaust into the primary fuel cell sub-assembly to assist in preheating thereof, and c) provide steam into the primary fuel cell sub-assembly to prevent coking of the anodes thereof. As the primary sub-assembly reaches its threshold temperature, it too begins to generate electricity and continues to self-heat and to be heated by the secondary sub-assembly. Preferably, the secondary sub-assembly continues to provide electricity in complement with the primary sub-assembly until the primary sub-assembly reaches full power, at which time the secondary sub-assembly may be shut down or switched to standby status for fuel efficiency, as desired.

Abstract: An apparatus and method for generating power, the apparatus, comprising: a steam engine for providing a first source of power, the steam engine also producing heat waste; a thermionic device for providing a second source of power, the thermionic device providing the second source of power from the heat waste which is provided to the thermionic device, the heat waste of the steam engine being in fluid communication with a heat exchanger of the thermionic device.

Abstract: Method for providing current regulation and current regulator for a power converter-driven electric machine are provided. The regulator includes a comparator coupled to receive a measurement of phase current from the machine and a reference phase current. The comparator is configured to provide an output signal indicative of whether or not the level of the measured phase current is below the reference phase current. The regulator further includes a circuit with memory of its respective circuit states, such as a flip-flop circuit. The circuit is coupled to the comparator to receive the output signal from the comparator. The circuit is further responsive to a stream of pulses having a generally fixed frequency to supply a switching signal synchronized with the stream of pulses.

Abstract: A method of operating a fuel cell includes the step of selectively connecting and disconnecting the fuel cell to at least one electrical load dependent at least in part upon at least one of a fuel cell voltage, a fuel cell current and a fuel cell temperature.

Abstract: A battery protection system for a battery having a switching mechanism positioned intermediate to the positive terminal and an electrical load of the battery. A controller manipulates the switching mechanism between an open position and a closed position, the closed position connects the electrical load to the battery and the open position disconnects the electrical load from the battery. The battery protection system utilizes a battery state-of-charge detection system, which instructs the controller to open the switching mechanism when the detection system detects a battery state-of-charge that is lower than a threshold value. The battery protection system is also equipped with a vehicle status detection system, which instructs the controller to close the switching mechanism when a vehicle startup condition is detected by the vehicle status detection system.

Abstract: Method and system for estimating rotor position of a switched reluctance machine is provided. The method allows for estimating flux linkage across a respective phase of the machine. The method allows for measuring of magnetization curves at aligned and unaligned positions of the machine. The method further allows for computing magnetization reference data between the aligned and unaligned positions. A storing step allows for storing rotor position data based on the magnetization reference data. The stored rotor position data is indicative of rotor position variation as a function of phase current. A relating step allows to relate the estimated flux linkage to the magnetization reference data to determine, for a respective phase current, correspondence of the estimated flux linkage relative to the magnetization reference data. A retrieving step allows for retrieving stored rotor position data when said correspondence is determined.

Abstract: Method and system for estimating rotor position of a switched reluctance machine is provided. The method allows for estimating flux linkage across a respective phase of the machine. The method allows for measuring of magnetization curves at aligned and unaligned positions of the machine. The method further allows for computing magnetization reference data between the aligned and unaligned positions. A storing step allows for storing rotor position data based on the magnetization reference data. The stored rotor position data is indicative of rotor position variation as a function of phase current. A relating step allows to relate the estimated flux linkage to the magnetization reference data to determine, for a respective phase current, correspondence of the estimated flux linkage relative to the magnetization reference data. A retrieving step allows for retrieving stored rotor position data when said correspondence is determined.

Abstract: Control methods for operating a power converter circuit, consisting of a full bridge DC/DC converter stage and a full bridge DC/AC inverter stage, for use in automobiles and other vehicles. The DC/DC converter is operated by pulse width modulation and by “soft switching” and “synchronous switching” which involves turning MOSFET switches OFF and ON at strategic times to gain improvements in system performance. The DC/DC converter is also operated at a relatively high and relatively constant duty cycle, and is controlled in such a way as to make the output operate as a current source. The DC/AC inverter has a cycle by cycle overload current protection scheme.

Abstract: A battery protection system for a battery having a switching mechanism positioned intermediate to the positive terminal and an electrical load of the battery. A controller manipulates the switching mechanism between an open position and a closed position, the closed position connects the electrical load to the battery and the open position disconnects the electrical load from the battery. The battery protection system utilizes a battery state-of-charge detection system, which instructs the controller to open the switching mechanism when the detection system detects a battery state-of-charge that is lower than a threshold value. The battery protection system is also equipped with a vehicle status detection system, which instructs the controller to close the switching mechanism when a vehicle startup condition is detected by the vehicle status detection system.

Abstract: Propulsion control system and method are provided for use in vehicles including a propulsion motor that is powered by a fuel cell. The fuel cell unit produces a compatible voltage for the propulsion motor, thereby removing the need for a dc/dc boost converter. A buck/boost converter and a standard 12 volt battery are used to start the fuel cell. An inverter receives dc electric voltage from the fuel cell and outputs ac electric voltage to the propulsion motor. A vehicle controller receives a voltage input from the fuel cell unit and outputs a current reference to a comparing device. The comparing device compares the current reference from the vehicle controller to an actual current of the fuel cell unit and then outputs a signal to a PI control which outputs a control signal to a fuel cell controller, whereby the power output of the fuel cell is controlled based on the actual current of the fuel cell.

Abstract: A battery protection system for a battery having a switching mechanism positioned intermediate to the positive terminal and an electrical load of the battery. A controller manipulates the switching mechanism between an open position and a closed position, the closed position connects the electrical load to the battery and the open position disconnects the electrical load from the battery. The battery protection system utilizes a battery state-of-charge detection system, which instructs the controller to open the switching mechanism when the detection system detects a battery state-of-charge that is lower than a threshold value. The battery protection system is also equipped with a vehicle status detection system, which instructs the controller to close the switching mechanism when a vehicle startup condition is detected by the vehicle status detection system.

Abstract: An induction motor drive uses direct vector control for zero speed start up. According to the invention, a speed sensorless induction motor is controlled at all speeds, including zero or substantially zero speed, using direct vector control. In order to utilize direct vector control at all speeds, it is necessary to derive accurate stator flux vectors at all speeds. This is accomplished in the present invention by calculating two sets of stator flux vectors in diverse manners. A first set of flux vectors is derived from measured stator terminal voltage quantities, and a second set of flux vectors is derived from measured stator current quantities. The first set of flux vectors is valid at non-zero speed and the second set of flux vectors is valid at substantially zero speed. The direct vector control utilizes one of the two sets of flux vectors in accordance with predetermined criteria indicative of zero and non-zero speed conditions.

Abstract: A three-phase invertor and control is disclosed for synthesizing low harmonic content AC voltage in the non-linear, or overmodulation, region of inverter operation. A field orientation control provides a reference voltage vector representing the desired AC output voltage in magnitude and angle. Three state, two state, and step inverter operations are used individually and in combinations in accordance with magnitude and angle parameters of the reference voltage vector.

Abstract: A speed sensorless hybrid vector control starts from zero speed by using indirect vector control with stator frequency equal to slip frequency. As soon as the rotor begins to rotate, the drive is converted to direct vector control for normal operation. The direct vector control uses several low pass filters. The first is a harmonic reducing filter for the sensed motor phase current and voltage signals. The others comprise integration apparatus used in the calculation of motor flux quantities from the motor phase current and voltage signals.

Abstract: An electrical power generation system includes a heat engine having an output member operatively coupled to the rotor of a dynamoelectric machine. System output power is controlled by varying an electrical parameter of the dynamoelectric machine. A power request signal is related to an engine speed and the electrical parameter is varied in accordance with a speed control loop. Initially, the sense of change in the electrical parameter in response to a change in the power request signal is opposite that required to effectuate a steady state output power consistent with the power request signal. Thereafter, the electrical parameter is varied to converge the output member speed to the speed known to be associated with the desired electrical output power.

Abstract: A quasi-resonant pole inverter provides soft-switching of the main inverter switch devices only when such opportunities are required by the pulse width modulation control. The inverter includes a main switching section and an auxiliary switching section. A phase-pole of the main switching section swings from source to ground potential with the assistance of the auxiliary switching section. The phase-pole swings from ground to source potential with the assistance of the auxiliary switching section. Low switch stresses are characteristic in both the main switching section devices and the auxiliary section switching devices. Main power is carried predominantly through the DC rails thereby minimizing power handling requirements of quasi-resonant reactive components.

Abstract: A control for an AC motor has first and second sets of three-phase stator windings wound physically in parallel and a three-phase inverter for each set. A first current sensor is responsive to a first phase current of the first set of three-phase stator windings; and a second current sensor is responsive to a phase current of the second set of three-phase windings other than that corresponding to the first phase current of the first set of three-phase windings. The control is responsive to signals from the first and second current sensors to generate a set of motor phase voltage control signals, which are provided to first and second three-phase inverters connected across a source of DC electric power.