Scroll Compressors with Different Volume Indexes and Systems and Methods for Same

Abstract

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.

Description

[0001]CROSS-REFERENCE TO RELATED PATENT APPLICATIONS[0002]This patent application claims the benefit of U.S. Provisional Patent Application No. 61 / 146,947, filed Jan. 23, 2009, the entire teachings and disclosure of which are incorporated herein by reference thereto.FIELD OF THE INVENTION[0003]The present invention relates to scroll compressors for compressing refrigerant and more particularly to efficiency improvements relative to a bank of two or more compressors that may be implemented in a cooling / refrigeration circuit, and is particularly advantageous for such compressors that have a built-in fixed volume index such as scroll or screw compressors.BACKGROUND OF THE INVENTION[0004]A scroll compressor is a certain type of compressor that is used to compress refrigerant for such applications as refrigeration, air conditioning, heat pumps, industrial cooling and freezer applications, and / or other applications where compressed fluid may be used. Such prior scroll compressors are know...

AI Technical Summary

Benefits of technology

[0008]A general objective of the present invention is to increase efficiency of compressors systems operating in both full or part load conditions. Further, the system can be optimized depending on various environmental conditions.

Problems solved by technology

Scroll compressors and / or other types of compressors are positive displacement machines and thereby may have a fixed and therefore non-adjustable “volume index”.

One drawback with employing such fixed positive displacement compressors is that the efficiency curve is fixed relative to operating temperature or to part load operation (e.g. due to condensing temperature differences due to seasonal changes as between summer and winter).

While making variable geometry compressors is possible, these adjustable machines have other drawbacks such as increased parts (e.g. controls and actuators and mechanical geometry adjustment structure) and thereby increased complexity and typically a substantial increased cost.

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