Abstract: A method for operation of a closed-cycle power conversion device includes receiving measured thermal information from one or more sensors that sense thermal characteristics of a hot portion of an absorber heat exchanger of a closed-cycle power conversion device which uses a working medium in its operation. The closed-cycle power conversion device is in thermal connection with a heat source, and absorption of heat from the heat source is proportional to a mass or mass flow rate of the working medium. If the measured thermal information is not in a defined normal range, a message is provided of an abnormality in operation of the closed-cycle power conversion device.

Abstract: Present implementations provide an approach that allows for a double-acting, multi-cylinder, thermodynamically resonant, alpha configuration free-piston Stirling system. The system includes overstroke preventers that control extent of piston travel to prevent undesirable consequences of piston travel beyond predetermined limits. The overstroke preventers involve controlled work extraction out of the system or controlled work input into the system. Implementations can also include duplex linear alternators, and/or frequency tuning systems, and/or vibration balancing configurations.

Abstract: An active balance system is provided for counterbalancing vibrations of an axially reciprocating machine. The balance system includes a support member, a flexure assembly, a counterbalance mass, and a linear motor or an actuator. The support member is configured for attachment to the machine. The flexure assembly includes at least one flat spring having connections along a central portion and an outer peripheral portion. One of the central portion and the outer peripheral portion is fixedly mounted to the support member. The counterbalance mass is fixedly carried by the flexure assembly along another of the central portion and the outer peripheral portion. The linear motor has one of a stator and a mover fixedly mounted to the support member and another of the stator and the mover fixedly mounted to the counterbalance mass. The linear motor is operative to axially reciprocate the counterbalance mass.

Abstract: An active balance system is provided for counterbalancing vibrations of an axially reciprocating machine. The balance system includes a support member, a flexure assembly, a counterbalance mass, and a linear motor or an actuator. The support member is configured for attachment to the machine. The flexure assembly includes at least one flat spring having connections along a central portion and an outer peripheral portion. One of the central portion and the outer peripheral portion is fixedly mounted to the support member. The counterbalance mass is fixedly carried by the flexure assembly along another of the central portion and the outer peripheral portion. The linear motor has one of a stator and a mover fixedly mounted to the support member and another of the stator and the mover fixedly mounted to the counterbalance mass. The linear motor is operative to axially reciprocate the counterbalance mass. A method is also provided.

Abstract: An active balance system is provided for counterbalancing vibrations of an axially reciprocating machine. The balance system includes a support member, a flexure assembly, a counterbalance mass, and a linear motor or an actuator. The support member is configured for attachment to the machine. The flexure assembly includes at least one flat spring having connections along a central portion and an outer peripheral portion. One of the central portion and the outer peripheral portion is fixedly mounted to the support member. The counterbalance mass is fixedly carried by the flexure assembly along another of the central portion and the outer peripheral portion. The linear motor has one of a stator and a mover fixedly mounted to the support member and another of the stator and the mover fixedly mounted to the counterbalance mass. The linear motor is operative to axially reciprocate the counterbalance mass. A method is also provided.