Techniques facilitating mechanical vibration management for cryogenic environments are provided. In one example, a system can comprise a processor that executes computer executable components stored in memory. The computer executable components can comprise a linearization component and a drive component. The linearization component can translate data indicative of a nonlinear drive signal into a linear drive signal. The drive component can dynamically control operation of a compressor of a cryocooler using the linear drive signal. The cryocooler can provide cooling capacity for a cryogenic environment.

The air conditioning system with solar-powered subcooling system includes a main cooling system having an evaporator, a compressor, a condenser, and an expansion valve configured to operate in a conventional vapor compression refrigerant cycle. The subcooling system includes a compressor, a condenser, and an expansion valve, the compressor being powered by at least one rechargeable battery connected to a photovoltaic solar panel. The main system and the subcooling system are linked by a heat exchanger having a primary coil in the main system between the condenser and the expansion valve and a secondary coil in the subcooling system disposed between the expansion valve and the compressor. The main system and the subcooling system may use the same type of refrigerant, or different refrigerant types. The additional cooling provided to the refrigerant in the main system by subcooling increases the efficiency of the air conditioning system.

Methods and systems for power management are provided. Aspects include receiving, by a controller, load data associated with two or more refrigeration systems, wherein the two or more refrigeration systems comprise at least a first refrigeration system and a second refrigeration system, determining, by the controller, an available power capacity for the first refrigeration system and the second refrigeration system, operating, by the controller, the first refrigeration system and the second refrigeration system in a plurality of modes based at least in part on the load data and the available power capacity, wherein the plurality of modes comprise an unloaded mode and a plurality of loaded modes.

An operation controlling apparatus of a reciprocating compressor includes: a detector configured to detect a torque output by a motor of the reciprocating compressor, a rotation speed of the motor, a counter electromotive voltage of the motor, and a current applied to the motor; a controller configured to determine a mode switching time point for switching an operation mode of the reciprocating compressor based on the torque, the rotation speed, the counter electromotive voltage, and the current of the motor, and output a control signal for changing a wire ratio of the motor corresponding to the operation mode; and a driver configured to change the wire ratio of the motor based on the control signal and operate the reciprocating compressor in the operation mode among at least two operation modes.

A vapor cycle compressor includes a motor section and a compression section operatively engaged with the motor section. A refrigerant path is in the motor section and in the compression section. The refrigerant path includes: a compression refrigerant path, for a single phase compression refrigerant, in the compression section; an inner rotor shaft refrigerant path, for a single phase inner rotor shaft refrigerant, in the compression section and in the motor section; and a stator refrigerant path, for a two phase stator refrigerant, in the motor section.

A system includes an electronic power converter and a controller. The electronic power converter supplies power to one or more motor drives of an HVAC system. The controller obtains a plurality of pulse width modulation (PWM) algorithms. Each PWM algorithm has an associated spectrum of frequencies. The controller further determines one or more resonance frequencies associated with the HVAC system. The controller also selects a first PWM algorithm from the plurality of PWM algorithms wherein the spectrum of frequencies of the first PWM algorithm lacks frequency peaks that overlap with the one or more resonance frequencies associated with the HVAC system. The controller further operates the electronic power converter according to the first PWM algorithm.

An air-conditioning apparatus including a compressor incorporating an electric motor; a temperature sensor configured to detect indoor temperature; a drive circuit configured to drive the electric motor; a connection switching device configured to switch connection of stator windings of the electric motor between a first connection state and a second connection state higher in line-to-line voltage than the first connection state; and a controller configured to enter thermo-off when the indoor temperature reaches a target temperature or a correction temperature set based on the target temperature and cause the connection switching device to switch connection, the thermo-off being entered by stopping the compressor via the drive circuit. When a thermo-off count reaches a reference count with the electric motor being in the first connection state, the controller causes the connection switching device to switch connection from the first connection state to the second connection state.

An air-conditioning apparatus includes a refrigerant circuit including a compressor, an indoor-side heat exchanger, and an outdoor-side heat exchanger; a drive circuit configured to drive an electric motor; a connection switching device configured to switch connection of stator windings of the electric motor between a first connection state and a second connection state higher in line-to-line voltage than the first connection state; and a controller configured to perform defrosting operation for removing frost formed on the outdoor-side heat exchanger and cause the connection switching device to switch connection. In performing the defrosting operation with the stator windings being in the second connection state, the controller causes the connection switching device to switch the connection of the stator windings from the second connection state to the first connection state.

An air-conditioner includes: a refrigerant circuit through which a refrigerant flows, the refrigerant circuit being formed of a compressor, a switching valve, a first heat exchanger, an expansion valve, and a second heat exchanger connected to one another by a first pipe; a heat-transfer medium circuit through which a heat-transfer medium flows, the heat-transfer medium circuit being formed of a pump, the first heat exchanger, and a third heat exchanger connected to one another by a second pipe; and control device that controls the compressor and the pump. In an operation of the air-conditioner performed before entering a defrosting operation, the control device increases a frequency of the compressor, as compared to the frequency of the compressor in a heating operation, and reduces a rotational speed of the pump, as compared to the rotational speed of the pump in the heating operation.

Disclosed are a compressor control method, control apparatus and control system. The method include: receiving a cylinder switching instruction, and detecting operating parameters of a compressor; determining whether a cylinder switching operation is completed according to the operating parameters of the compressor; and after it is determined that the cylinder switching operation is completed, performing torque compensation.