A heat transfer system cycles between a first mode where a heat transfer fluid is directed to a first electrocaloric module and from the first electrocaloric module to a heat exchanger to a second electrocaloric module while one of the first and second electrocaloric modules is energized, and a second mode where the heat transfer fluid is directed to the second electrocaloric module and from the second electrocaloric module to the heat exchanger to the first electrocaloric module, while the other of the first and second electrocaloric modules is energized. The modes are repeatedly cycled in alternating order directing the heat transfer fluid to cause a temperature gradient in each of the first and second electrocaloric modules, and fluid from a flow path between the electrocaloric modules is mixed with circulating fluid from a conditioned space to cool or heat the conditioned space.

An electrocaloric element for a heat transfer system includes an electrocaloric material of a copolymer of (i) vinylidene fluoride, and (ii) an addition polymerization monomer that is larger than vinylidene fluoride and includes a substituent more electronegative than chlorine. Electrodes are disposed on opposite surfaces of the electrocaloric material, and an electric power source is configured to provide voltage to the electrodes. The system also includes a first thermal flow path between the electrocaloric material and a heat sink, and a second thermal flow path between the electrocaloric material and a heat source.

In order to provide a cascade heat pump with which a large temperature lift can be provided with high efficiency, a cascade heat pump comprising n stages where n≥2 is proposed. Each of the n stages has a heat pump with a coolant inlet, a first coolant outlet, and a second coolant outlet. Each heat pump has a hot side and a cold side and a flow divider to divide a coolant flow entering the coolant inlet between the hot side and the cold side. The first coolant outlet of the heat pump of each stage i, where i=1 . . . n−1, is connected to the coolant inlet of the heat pump of a subsequent stage i+1. The second coolant outlet of the heat pump of at least one subsequent stage i+1 is connected by a recirculation line to the coolant inlet of the heat pump of a preceding stage.

A cooling apparatus that cools a cooling target object in a state in which an electromagnetic field or an electric field acts on the cooling target object is provided. The cooling apparatus includes a refrigeration machine to cool a cooling target object, an electromagnetic wave irradiation device to generate an electromagnetic field which acts on the cooling target object, a controller to control operations of the refrigeration machine and the electromagnetic wave irradiation device and perform a subcooling operation of cooling the cooling target object by using the refrigeration machine in a state in which the electromagnetic field is generated, and a temperature sensor to measure a temperature of the cooling target object. In the subcooling operation, the controller controls the intensity of the electromagnetic field generated by the electromagnetic wave irradiation device in accordance with the temperature measured by the temperature sensor.

A module for warming and, alternately, for cooling, this module comprising an electrocaloric capacitor, an electrical energy storage device and a controllable circuit for transferring electrical energy between the electrocaloric capacitor and the energy storage device. The controllable circuit comprising an inductor connected between the electrocaloric capacitor and the storage device and at least one controllable switch. There is further included a unit programmed to control the switch so as to cause the transfer circuit to toggle successively into the following states and in the following order: an energy recovery state, a disabled state in which it electrically isolates the electrocaloric capacitor and the energy storage device, an energy release state and the disabled state, and each time to maintain the transfer circuit in the disabled state for a duration greater than a predetermined threshold.

A thermal stabilization system stabilizes inertial measurement unit (IMU) performance by reducing or slowing operating variations over time of the internal temperature. More specifically, a thermoelectric heating/cooling device operates according to the Peltier effect, and uses thermal insulation and a mechanical assembly to thermally and mechanically couple the IMU to the thermoelectric device. The thermal stabilization system may minimize stress on the IMU and use a control system to stabilize internal IMU temperatures by judiciously and bidirectionally powering the thermoelectric heating/cooling device. The thermal stabilization system also may use compensation algorithms to reduce or counter residual IMU output errors from a variety of causes such as thermal gradients and imperfect colocation of the IMU temperature sensor with inertial sensors.

An improved method to manage the flow of heat in an active regenerator in a magnetocaloric or an electrocaloric heat-pump refrigeration system, in which heat exchange fluid moves synchronously with the motion of a magnetic or electric field. Only a portion of the length of the active regenerator bed is introduced to or removed from the field at one time, and the heat exchange fluid flows from the cold side toward the hot side while the magnetic or electric field moves along the active regenerator bed.

A heat transfer system is disclosed in which, an electrocaloric material includes a copolymer of a monomer mixture including (i) vinylidene fluoride, (ii) an addition polymerization monomer selected from tetrafluoroethylene, trifluoroethylene, or a monomer smaller than trifluoroethylene, and (iii) a halogenated addition polymerization monomer different than (ii) that is larger than vinylidene fluoride. The electrocaloric material also includes an additive selected from a nucleating agent having a polar surface charge, electrocalorically active solid particles, or a combination thereof. Electrodes are disposed on opposite surfaces of the electrocaloric material, and an electric power source is configured to provide voltage to the electrodes. The system also includes a first thermal flow path between the electrocaloric material and a heat sink, and a second thermal flow path between the electrocaloric material and a heat source.

An electrocaloric effect element includes a laminate including an electrode layer mainly including Pt and a ceramic layer that are stacked, in which the ceramic layer has a perovskite structure and mainly includes a ceramic including Pb, Sc, and Ta, where a content ratio of Sc is y, a content ratio of Ta is 1−y, and a range of the y is about 0.450≤y≤about 0.495.

A building heating or cooling system is disclosed that includes an air handling system having an air delivery flow path in fluid communication with a conditioned space in the building. The building heating or cooling system also includes an electrocaloric heating or cooling system that includes first and second electrocaloric modules. A first inlet receives air from the conditioned space or the air delivery flow path and directs it through the first or second electrocaloric module to a first outlet to the conditioned space or the air delivery flow path, and a second inlet that receives air from the conditioned space or the air delivery flow path and directs it through the first or second electrocaloric module to a second outlet to outside the conditioned space.