US5735134A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Set point optimization in vapor compression cycles
Assignee: Massachusetts Institute of Technology
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Filing: 1996-05-30
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Granted: 1998-04-07
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Expires: 2016-05-30
Abstract
Abstract A vapor compression system with set point optimization generates a set of thermodynamic operating parameters such that the system operates with optimum energy efficiency. Based on environmental conditions such as indoor and outdoor temperature as well as thermal load, the set of parameters for steady-state set point is generated. The system also monitors actual system properties in real-time and provides them as feedback to the set point computation module. Based on these actual real-time measurements, a new steady-state set point can be generated to enable the system to continue operating at maximum coefficient of performance upon change in environmental or thermal load requirements.
Inventors
- 👤 Sheng Liu
- 👤 Xiang-Dong He
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 14:04
CPC Classifications
G; G05; G05B; G05B13/00; G05B13/02; G05B13/0205; G05B13/024; F; F25; F25B; F25B49/00; F25B49/02; F25B2500/00; F25B2500/19; F25B2600/00; F25B2600/21
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
99 words
A method of controlling a vapor compression cycle in a vapor compression system comprising: (a) generating a set of parameters which define an operating condition for the vapor compression system; (b) operating the vapor compression system in accordance with the set of parameters; (c) while the system operates, receiving a real-time measurement of at least one of the parameters; (d) using the real-time measurement, calculating the real-time coefficient of performance of the vapor compression system; (e) adjusting the at least one parameter; and (f) repetitively performing steps (c) through (e) as required to maximize the real-time coefficient of performance.
Claim 2
Independent Claim
99 words
A method of controlling a vapor compression cycle in a vapor compression system comprising: (a) generating a set of parameters which define an operating condition for the vapor compression system; (b) operating the vapor compression system in accordance with the set of parameters; (c) while the system operates, receiving a real-time measurement of at least one of the parameters; (d) using the real-time measurement, calculating the real-time coefficient of performance of the vapor compression system; (e) adjusting the at least one parameter; and (f) repetitively performing steps (c) through (e) as required to maximize the real-time coefficient of performance.
Claim 3
Dependent Claim
21 words
The method of claim 1 wherein the at least one parameter is temperature of a refrigerant of the vapor compression system.
Claim 4
Dependent Claim
18 words
The method of claim 1 further comprising providing a multivariable controller for adjusting the at least one parameter.
Claim 5
Dependent Claim
21 words
The method of claim 3 further comprising adjusting a gain of the multivariable controller to adjust the at least one parameter.
Claim 6
Dependent Claim
18 words
The method of claim 1 further comprising receiving an environmental input used in generating the set of parameters.
Claim 7
Dependent Claim
26 words
The method of claim 1 wherein the step of repetitively performing steps (c) through (e) comprises an iterative search for a maximum real-time coefficient of performance.
Claim 8
Dependent Claim
29 words
The method of claim 1 wherein the step of adjusting the at least one parameter comprises adjusting at least one control input to control a component of the system.
Claim 9
Dependent Claim
15 words
The method of claim 5 wherein the environmental input comprises a measurement of indoor temperature.
Claim 10
Dependent Claim
15 words
The method of claim 5 wherein the environmental input comprises a measurement of outdoor temperature.
Claim 11
Dependent Claim
16 words
The method of claim 5 wherein the environmental input comprises a measurement of system thermal load.
Claim 12
Dependent Claim
16 words
The method of claim 7 wherein the at least one control input controls a valve opening.
Claim 13
Dependent Claim
17 words
The method of claim 7 wherein the at least one control input controls a condenser fan speed.
Claim 14
Dependent Claim
17 words
The method of claim 7 wherein the at least one control input controls a compressor fan speed.
Claim 15
Dependent Claim
18 words
The method of claim 7 wherein the at least one control input controls a speed of a compressor.
Claim 16
Dependent Claim
15 words
The method of claim 14 wherein the iterative search comprises a constrained gradient descent search.
Claim 17
Dependent Claim
80 words
A vapor compression system comprising: means for generating a set of parameters which define an operating condition for the vapor compression system; means for generating a real-time measurement of at least one of the parameters as the vapor compression system operates; and means for repetitively calculating the real-time coefficient of performance of the vapor compression system using the real-time measurement of the at least one parameter and adjusting the at least one parameter to maximize the real-time coefficient of performance.
Claim 18
Dependent Claim
80 words
A vapor compression system comprising: means for generating a set of parameters which define an operating condition for the vapor compression system; means for generating a real-time measurement of at least one of the parameters as the vapor compression system operates; and means for repetitively calculating the real-time coefficient of performance of the vapor compression system using the real-time measurement of the at least one parameter and adjusting the at least one parameter to maximize the real-time coefficient of performance.
Claim 19
Dependent Claim
23 words
The vapor compression system of claim 16 wherein the at least one parameter is temperature of a refrigerant in the vapor compression system.
Claim 20
Dependent Claim
18 words
The vapor compression system of claim 16 further comprising a multivariable controller for adjusting at least one parameter.
Claim 21
Dependent Claim
27 words
The vapor compression system of claim 18 further comprising a gain scheduler for altering a gain in the multivariable controller to adjust the at least one parameter.
Claim 22
Dependent Claim
33 words
The vapor compression system of claim 16 further comprising means for adjusting at least one control input to control a component of the vapor compression system to adjust the at least one parameter.
Claim 23
Dependent Claim
20 words
The vapor compression system of claim 20 wherein the at least one control input controls a speed of a compressor.
Claim 24
Dependent Claim
18 words
The vapor compression system of claim 20 wherein the at least one control input controls a valve opening.
Claim 25
Dependent Claim
19 words
The vapor compression system of claim 20 wherein the at least one control input controls a condenser fan speed.
Claim 26
Dependent Claim
19 words
The vapor compression system of claim 20 wherein the at least one control input controls a compressor fan speed.
Claim 27
Dependent Claim
39 words
The vapor compression system of claim 16 further comprising means for providing an environmental input defining a condition of the environment in which the vapor compression system operates, the environmental input being used to generate the set of parameters.
Claim 28
Dependent Claim
17 words
The vapor compression system of claim 25 wherein the environmental input comprises a measurement of indoor temperature.
Claim 29
Dependent Claim
17 words
The vapor compression system of claim 25 wherein the environmental input comprises a measurement of outdoor temperature.
Claim 30
Dependent Claim
18 words
The vapor compression system of claim 25 wherein the environmental input comprises a measurement of system thermal load.
Claim 31
Dependent Claim
34 words
The vapor compression system of claim 16 wherein the means for repetitively calculating the real-time coefficient of performance of the vapor compression system performs an iterative search to maximize the real-time coefficient of performance.
Claim 32
Dependent Claim
17 words
The vapor compression system of claim 29 wherein the iterative search comprises a constrained gradient descent search.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2001-04-06 | 2001-10-06 | 2002-04-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-04-06 | 2005-10-06 | 2006-04-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-04-06 | 2009-10-06 | 2010-04-07 | $7700.00 | Window Closed / Lapsed |