A plurality of scroll compressors with different fixed volume indexes are connected in fluid parallel circuit and configured to selectively operate to maximize isentropic efficiency at different condensing temperatures. Different quantities of scroll compressors of different volume indexes may be selected based upon typical climate or geographic location environmental conditions to attempt to maximize efficiency. A controller may selectively operate different combinations of the compressors of different volume indexes bases up load demands and condensing temperature conditions, which may be determined in a variety of ways.

A vacuum system having a condenser and a root vacuum pump set includes an independent inlet condenser set having an inlet end for receiving vapor inputted from an output of an air cooling power generator condenser of a generator; air in the vapor being condensed, and the surplus air is outputted; a root vacuum pump set including at least one root vacuum pump; the root vacuum pump set further including an input end and an output end; the input end being connected to the independent inlet condenser set; air outputted from the independent inlet condenser set being inputted to the at least one root vacuum pump for compression and then the compressed air being outputted from the output end; and a backing pump connected to the output end of the root vacuum pump set by using an output pipe; the backing pump serving to receive air outputted from the root vacuum pump set.

A plurality of scroll compressors with different fixed volume indexes are connected in fluid parallel circuit and configured to selectively operate to maximize isentropic efficiency at different condensing temperatures. Different quantities of scroll compressors of different volume indexes may be selected based upon typical climate or geographic location environmental conditions to attempt to maximize efficiency. A controller may selectively operate different combinations of the compressors of different volume indexes bases up load demands and condensing temperature conditions, which may be determined in a variety of ways.

An improved compressed air system utilizes one or more base compressors, such as fixed speed drive compressors, to meet the compressed air demands and one or more trim compressors, such as variable speed drive compressors, to meet the variations in the demand. The operation of both the base and trim compressors may be controlled to provide improved overall efficiency while meeting the transient load demands. The control may spread the demands over the various base compressors to improve the overall loading on each base compressor. Efficiency metrics may be utilized to control the switching between base and trim compressors. Unloading of a base compressor may be controlled to avoid undesirable changes in system performance.

The present disclosure relates to an air conditioner and a compressor. The compressor includes: a first cylinder assembly, including a first cylinder body and a first sliding vane, a volume control assembly, including a pressure regulator; wherein the pressure regulator is provided with a storage cavity, and the storage cavity is communicated with the variable volume control cavity; wherein the first sliding vane is configured to slide in a reciprocating manner between the first compression cavity and the variable volume control cavity along the first sliding vane groove, to change the volume of the variable volume control cavity; and the refrigerant introduced into the variable volume control cavity flows between the variable volume control cavity and the storage cavity along with a change of the volume of the variable volume control cavity.

Disclosed are a variable capacity compressor operation mode determination method and device, a variable capacity compressor and an air conditioner. The variable capacity compressor operation mode determination method includes: detecting a current value of a compressor at present as A1 before switching an operation mode of the compressor; detecting the current value of the compressor at present as A2 after switching the operation mode of the compressor and reaching a preset time; comparing A1 and A2, determining that the switching of the operation mode of the compressor is successful when a ratio relationship between A1 and A2 satisfies a preset condition, and determining that switching of the operation mode of the compressor is failed when the ratio relationship between A1 and A2 dissatisfies a preset condition.

The multi-compressor system (7) has a plurality of parallelly coupled compressors (8); inlet connection lines (15) each connected to a refrigerant suction fitting of a respective compressor (8); outlet connection lines (17) each connected to a refrigerant discharge fitting of a respective compressor (8); a common oil balancing line (18) and balancing connection lines (19) each connecting the common oil balancing line (18) to an oil balancing connection (21) of a respective compressor (8); and spring-loaded normally-open valves (25) each being arranged within a respective balancing connection line (19) or within an oil balancing connection (21) of a respective compressor (8) and each being configured to close when a pressure difference between a pressure prevailing in the low pressure volume of the respective compressor (8) and a pressure prevailing in the common oil balancing line (18) reaches a predetermined value.

Disclosed are a variable capacity compressor operation mode determination method and device, a variable capacity compressor and an air conditioner. The variable capacity compressor operation mode determination method includes: detecting a current value of a compressor at present as A1 before switching an operation mode of the compressor; detecting the current value of the compressor at present as A2 after switching the operation mode of the compressor and reaching a preset time; comparing A1 and A2, determining that the switching of the operation mode of the compressor is successful when a ratio relationship between A1 and A2 satisfies a preset condition, and determining that switching of the operation mode of the compressor is failed when the ratio relationship between A1 and A2 dissatisfies a preset condition.

Systems and methods for providing lubricant from a first compressor to a second compressor are provided. A control module receives a start command for a climate-control system having the first and second compressors, allows lubricant from the first compressor to flow into an inlet of the second compressor, turns the second compressor to an ON-mode, and prevents lubricant from the first compressor from flowing into the inlet of the second compressor after the second compressor has been in the ON-mode for a predetermined time period.

A method and a device for controlling a capacity change of a compressor, and a smart home appliance. The method includes: determining whether a capacity of the compressor is required to be changed; if yes, determining an intermediate frequency; changing the capacity of the compressor while maintaining the operating frequency of the compressor at the intermediate frequency; and the maintaining the operating frequency of the compressor at the intermediate frequency reduces a sudden change in output of the compressor after the changing the capacity.