Abstract: An ocean wave-driven sea water desalination plant employs ocean bottom mounted and hinged flaps driven in oscillating motion by wave surge force to drive rotary pumps which directly pressurize filtered sea water for use by a reverse osmosis (RO) plant and a hydraulic motor-generator set which provides electrical power to RO plant peripheral devices. Means are provided to control the filtered sea water pressure presented to the RO membranes to a preferred set point value. Means are also provided to control the pump reaction torque presented to the flap independently of water pressure by adjusting the effective pump displacement with a pulse width modulated valve shunting the pump ports to maximize captured wave power. Control of pump reaction torque may be effected slowly according to average sea state conditions or in real-time to further enhance captured wave power.

Abstract: A system for generating power from a flow of liquid having at most fifty feet of head and a flow rate of at most 300 cubic feet per second, includes: an axial-flow turbine, a penstock, an intake, a generator, and a control circuit. Each blade of the turbine runner is releasably coupled to the hub and each blade: 1) is configured to extract energy from liquid flowing through the runner by rotating the hub when the flow of liquid contacts the blade, and 2) has a pitch that is adjustable. The length of the penstock is adjustable. The generator is operable to generate electric power from rotation of the turbine. The control circuit to determines changes in the flow of liquid and in response modifies at least one of the following: 1) the speed of the axial-flow turbine's hub, and 2) the flow of liquid that the runner receives.

Abstract: A system for generating power from a flow of liquid having at most fifty feet of head and a flow rate of at most 300 cubic feet per second, includes: an axial-flow turbine, a penstock, an intake, a generator, and a control circuit. Each blade of the turbine runner is releasably coupled to the hub and each blade: 1) is configured to extract energy from liquid flowing through the runner by rotating the hub when the flow of liquid contacts the blade, and 2) has a pitch that is adjustable. The length of the penstock is adjustable. The generator is operable to generate electric power from rotation of the turbine. The control circuit to determines changes in the flow of liquid and in response modifies at least one of the following: 1) the speed of the axial-flow turbine's hub, and 2) the flow of liquid that the runner receives.

Abstract: A simple and robust variable coaxial capacitive sensor and detection method for monitoring the position of a rapidly reciprocating member such as a piston or displacer in a free piston Stirling engine. The coaxial capacitor of the present invention in a preferred embodiment thereof is configured to modulate capacitive electrode area rather than inter-electrode spacing and as a result a highly linear transfer function can be achieved. Also disclosed are detection methods which derive and process signals in connection with applications which have small sensor capacitance variations while suppressing stray capacitance error.

Abstract: A system is provided for balancing state of charge among plural series connected electrical energy storage units that includes a power converter that selectively couples to an individual storage unit of the a string of electrical energy storage units and transfers energy by bidirectionally between the individual storage unit and the string of storage units.

Abstract: A system is provided for balancing state of charge among plural series connected electrical energy storage units that includes a power converter that selectively couples to an individual storage unit of the a string of electrical energy storage units and bidirectionally transfers energy between the individual storage unit and the string of storage units.

Abstract: A system and method of balancing state of charge among plural series connected electrical energy storage unit is provided. Individual storage units are selectively coupled by semiconductor switches for monitoring and balancing state of charge. When the state of charge of a selected unit is greater than a target state of charge, energy is transferred from the selected unit to the string of storage units, such that the state of charge of the selected unit converges toward the target state of charge. Conversely, when the state of charge of a selected unit is less than a target state of charge, energy is transferred from the string of storage units to the selected unit, such that the state of charge of the selected unit converges toward the target state of charge.

Abstract: A linear electrical machine may function as an alternator or a motor. Three annular magnets may be provided that move relative to a core. The magnets may all have a different magnetic orientation. Two magnets may have a north pole oriented in a direction parallel to an axis along which the magnets move relative to the core. Another magnet may have a north pole oriented in a direction perpendicular to the axis. The core may include a plurality of ferromagnetic core elements; and a support structure composed of a composite material defining plural spaces, each for receiving one of the plurality of core elements. The core may further include a core shield disposed on the support structure substantially following a perimeter of the support structure defining an opening through which a reciprocating element can pass.

Abstract: A simple and robust variable coaxial capacitive sensor and detection method for monitoring the position of a rapidly reciprocating member such as a piston or displacer in a free piston Stirling engine. The coaxial capacitor of the present invention in a preferred embodiment thereof is configured to modulate capacitive electrode area rather than inter-electrode spacing and as a result a highly linear transfer function can be achieved. Also disclosed are detection methods which derive and process signals in connection with applications which have small sensor capacitance variations while suppressing stray capacitance error.

Abstract: A control system for a Stirling engine including the use of a synchronous power converter (“SPC”) which is connected to the terminals of the alternator in a linear alternator/FPSE power system. According to the teachings of the present invention, the attached SPC is small and portable and further ensures that piston and displacer excursion within the system remain within design limits. The system and method are designed such that it is possible to adjust both the voltage amplitude and the waveform frequency at the terminals of the linear alternator. By controlling these operational aspects, both the speed and the range of travel associated with the piston and the displacer in the FPSE can be controlled.

Abstract: A system and method for determining and balancing state of charge among plural series connected electrical energy storage units is provided. State of change of a selected storage unit in a string of storage units is determined by (i) applying a non-dissipative load to the selected storage unit, resulting in an energy transfer between the selected storage unit and the string of electrical energy storage units through the non-dissipative load and (ii) determining the state of charge of the selected unit from voltage and current data of the selected storage unit resulting from the energy transfer. When the state of charge of the selected unit is different than a target state of charge, energy can be transferred between the selected unit and the string of storage units, such that the state of charge of the selected unit converges toward the target state of charge.

Abstract: A simple and robust variable coaxial capacitive sensor and detection method for monitoring the position of a rapidly reciprocating member such as a piston or displacer in a free piston Stirling engine. The coaxial capacitor of the present invention in a preferred embodiment thereof is configured to modulate capacitive electrode area rather than inter-electrode spacing and as a result a highly linear transfer function can be achieved. Also disclosed are detection methods which derive and process signals in connection with applications which have small sensor capacitance variations while suppressing stray capacitance error.

Abstract: An internal gear fluid displacement pump.

Abstract: A linear electrical machine may function as an alternator or a motor. Three annular magnets may be provided that move relative to a core. The magnets may all have a different magnetic orientation. Two magnets may have a north pole oriented in a direction parallel to an axis along which the magnets move relative to the core. Another magnet may have a north pole oriented in a direction perpendicular to the axis.

Abstract: A simple and robust variable coaxial capacitive sensor and detection method for monitoring the position of a rapidly reciprocating member such as a piston or displacer in a free piston Stirling engine. The coaxial capacitor of the present invention in a preferred embodiment thereof is configured to modulate capacitive electrode area rather than inter-electrode spacing and as a result a highly linear transfer function can be achieved. Also disclosed are detection methods which derive and process signals in connection with applications which have small sensor capacitance variations while suppressing stray capacitance error.

Abstract: A control system for a Stirling engine including the use of a synchronous power converter (“SPC”) which is connected to the terminals of the alternator in a linear alternator/FPSE power system. According to the teachings of the present invention, the attached SPC is small and portable and further ensures that piston and displacer excursion within the system remain within design limits. The system and method are designed such that it is possible to adjust both the voltage amplitude and the waveform frequency at the terminals of the linear alternator. By controlling these operational aspects, both the speed and the range of travel associated with the piston and the displacer in the FPSE can be controlled.

Abstract: A linear electrical machine may function as an alternator or a motor. Three annular magnets may be provided that move relative to a core. The magnets may all have a different magnetic orientation. Two magnets may have a north pole oriented in a direction parallel to an axis along which the magnets move relative to the core. Another magnet may have a north pole oriented in a direction perpendicular to the axis.

Abstract: A system and method of balancing state of charge among plural series connected electrical energy storage unit is provided. Individual storage units are selectively coupled by semiconductor switches for monitoring and balancing state of charge. When the state of charge of a selected unit is greater than a target state of charge, energy is transferred from the selected unit to the string of storage units, such that the state of charge of the selected unit converges toward the target state of charge. Conversely, when the state of charge of a selected unit is less than a target state of charge, energy is transferred from the string of storage units to the selected unit, such that the state of charge of the selected unit converges toward the target state of charge.

Abstract: A system is provided for balancing state of charge among plural series connected electrical energy storage units that includes a power converter that selectively couples to an individual storage unit of the a string of electrical energy storage units and transfers energy by bidirectionally between the individual storage unit and the string of storage units.

Abstract: A system and method for determining and balancing state of charge among plural series connected electrical energy storage units is provided. State of change of a selected storage unit in a string of storage units is determined by (i) applying a non-dissipative load to the selected storage unit, resulting in an energy transfer between the selected storage unit and the string of electrical energy storage units through the non-dissipative load and (ii) determining the state of charge of the selected unit from voltage and current data of the selected storage unit resulting from the energy transfer. When the state of charge of the selected unit is different than a target state of charge, energy can be transferred energy between the selected unit and the string of storage units, such that the state of charge of the selected unit converges toward the target state of charge.