44 results about "Linear alternator" patented technology

A thermoacoustic engine-generator that converts waste heat into electrical power. Thermal energy is converted to useful work via temperature-pressure amplification of periodic acoustic traveling waves in a compressible working fluid which cause the armature of a linear alternator to reciprocate and produce alternating current electrical energy. An external oscillator initiates reciprocating motion in the armature of a linear alternator. The armature is a combination fluid pump and fluid motor as well as the induction armature of a linear alternator. The pump end of the armature generates an acoustic traveling wave with each cycle of the armature. The traveling wave enters a waveguide-heat exchanger and is amplified in temperature, pressure and propagation velocity by thermal conduction of energy through the wall of the waveguide. The amplified traveling wave acts upon the opposite end of the armature, causing it to reciprocate within the magnetic field windings of the generator, and generate an electrical current as well as a new acoustic traveling wave. When the operating temperature gradient is attained across the hot and cold heat exchangers, the thermoacoustic engine-generator becomes acoustically resonant and self-regenerative, and will continue to operate as long as the thermal gradient is maintained. The theoretical conversion efficiency is dependent on the thermal gradient, and is 63% of Carnot.

A locomotive auxiliary power system and control techniques for such a system are provided. In one exemplary embodiment the auxiliary power system includes an auxiliary alternator coupled to the internal combustion engine of the locomotive. The system further includes an auxiliary power bus powered by the auxiliary alternator. A rectifier may be connected between the auxiliary alternator and the auxiliary power bus. A plurality of devices may be electrically powered by the auxiliary power bus. A respective inverter is connected between the auxiliary power bus and each device, wherein the inverter provides a path for diverting electrical power generated during a transient mode by at least one the plurality of devices. In one exemplary embodiment, the auxiliary alternator is made up of a single alternator connected through a single shaft to the internal combustion engine.

A beta-type free-piston Stirling cycle engine or cooler is drivingly coupled to a linear alternator or linear motor and has an improved balancing system to minimize vibration without the need for a separate vibration balancing unit. The stator of the linear motor or alternator is mounted to the interior of the casing through an interposed spring to provide an oscillating system permitting the stator to reciprocate and flex the spring during operation of the Stirling machine and coupled transducer. The natural frequency of oscillation, ωs, of the stator is maintained essentially equal toωp⁢1-αpkpand the natural frequency of oscillation of the piston, ωp, is maintained essentially equal to the operating frequency, ωo of the coupled Stirling machine and alternator or motor. For applications in which variations of the average temperature and / or the average pressure of the working gas cause more than insubstantial variations of the piston resonant frequency ωp, various alternative means for compensating for those changes in order to maintain vibration balancing are also disclosed.

A feedback control method and circuit for inclusion in a control system of an electrical power generating source that comprises a free piston Stirling engine driving a linear alternator. An instantaneous value of a variable, Vinternal, is continuously derived from other sensed and computed parameters and used in a negative feedback control loop of the control system to control engine piston stroke in order to maintain the power produced by the engine equal to the power transferred from the engine to the alternator. Vinternal is the sum of the voltage induced on the alternator winding and the voltage across the equivalent circuit lumped resistance of the alternator winding and a switching mode rectifier connects the alternator winding to an energy storage capacitor or battery. A negative feedback, alternator current control loop has an output connected to the pulse width modulator of the switching mode rectifier and has a feedback circuit comprising a current sensor for sensing instantaneous alternator current. A negative feedback, Vinternal control loop has a feedback circuit including a piston position or velocity sensor connected to a computing circuit that the current sensor is also connected to. The computing circuit computes a signal representing Vinternal for use as the feedback signal of the Vinternal control loop. The output of the Vinternal control loop is connected as the command input to the current feedback control loop.

Apparatus for transferring a linear load through a high-speed rotating member includes a linear actuator containing an axially translatable cylinder rod. A mounting adapter fixed against axial and rotary movement is rigidly affixed to an actuator cylinder containing the cylinder rod. An elongate guide sleeve, fixed to the mounting adapter, extends axially from the adapter to accommodate an axially translatable thrust bearing affixed to one end of the cylinder rod. The guide sleeve contains a linear slot for accommodating a guide pin affixed to the thrust bearing housing, and transversely movable within the linear slot to prevent rotation of both bearing housing and cylinder rod components.

A free piston engine is configured with a pair of opposed engine cylinders located on opposite sides of a fluid pumping assembly. An inner piston assembly includes a pair of inner pistons, one each operatively located in a respective one of the engine cylinders, with a push rod connected between the inner pistons. The push rod extends through an inner pumping chamber in the fluid pumping assembly and forms a fluid plunger within this chamber. An outer piston assembly includes a pair of pistons, one each operatively located in a respective one of the engine cylinders, with at least one pull rod connected between the outer pistons. The pull rod extends through an outer pumping chamber in the fluid pumping assembly and forms a fluid plunger within this chamber. The movement of the inner and outer piston assemblies during engine operation will cause the fluid plungers to pump fluid from a low pressure container into a high pressure chamber as a means of storing the energy output from the engine. Alternatively, the piston assemblies may drive a linear alternator. Located adjacent to at least one of the pistons are oil holes, with an oil mist annulus supplying oil mist therethrough. The oil in the oil mist will lubricate the engine cylinder wall while minimizing the oil consumption of the engine.