System and method for position control of a mechanical piston in a pump

Abstract

Embodiments of the systems and methods disclosed herein utilize a brushless DC motor (BLDCM) to drive a singie-stage or a multi-stage pump in a pumping system for real time, smooth motion, and extremely precise and repeatable position control over fluid movements and dispense amounts, useful in semiconductor manufacturing. The BLDCM may employ a position sensor for real time position feedback to a processor executing a custom field-oriented control scheme. Embodiments of the invention can reduce heat generation without undesirably compromising the precise position control of the dispense pump by increasing and decreasing, via a custom control scheme, the operating frequency of the BLDCM according to the criticality of the underlying function(s). The control scheme can run the BLDCM at very low speeds while maintaining a constant velocity, which enables the pumping system to operate in a wide range of speeds with minimal variation, substantially increasing dispense performance and operation capabilities.

Description

[0001] This divisional application is based on the application number 200680050665.7 (its international application number is PCT / US2006 / 044907), the application date is November 20, 2006, and the invention title is "A system for position control of a mechanical piston in a pump and Method" is a divisional application of the Chinese patent application. [0002] Cross References to Related Applications [0003] This application claims U.S. Provisional Patent Application No. 60 / 741660 (filed December 2, 2005, titled "SYSTEM AND METHOD FOR POSITION CONTROL OF A MECHANICAL PISTON IN A PUMP") and 60 / 841725 (filed 2006 September 1, 2011, titled "SYSTEM AND METHOD FOR POSITION CONTROL OF A MECHANICAL PISTON IN A PUMP"), both documents are therefore incorporated herein by reference. technical field [0004] The present invention generally relates to fluid pumps. In particular, embodiments of the invention relate to systems and methods for position control of mechanical pistons in mo...

AI Technical Summary

Problems solved by technology

These pressure spikes and subsequent pressure drops may damage the fluid (i.e. may adversely alter the physical characteristics of the fluid)

Additionally, pressure spikes may result in fluid pressure buildup, which may cause the dispense pump to dispense more fluid than intended, or to dispense fluid in a manner that has unfavorable dynamic characteristics

Also, since these problems are interrelated, sometimes fixing one problem can cause more problems and / or make things worse

[0008] Typically, pumping systems cannot satisfactorily control pressure changes during cycling

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