Adaptive real-time optimization control

• US 7,827,813 B2
• Filed: 01/30/2007
• Issued: 11/09/2010
• Est. Priority Date: 01/30/2007
• Status: Active Grant

• Current Assignee: Tyco Fire & Security GmbH (Johnson Controls International plc)
• Original Assignee: Johnson Controls Technology Company (Johnson Controls International plc)
• Inventors: Seem, John E.
• Primary Examiner(s): Jules; Frantz F
• Assistant Examiner(s): Cox; Alexis K
• Application Number:
  US11/699,860
• Publication Number:
  US 20080179409A1
• Time in Patent Office: 1,379 Days
• Field of Search: 236/49.3, 236/1.C, 236/1.E, 236/44.C, 621/32, 621/86, 621/766, 454/258
• US Class Current: 62/186
• CPC Class Codes: F24F 11/0001 for ventilation F24F11/30 takes precedence
• CPC Class Codes: F24F 11/30 for purposes related to the operation of the system, e.g. for safety or monitoring
• CPC Class Codes: F24F 11/46 Improving electric energy efficiency or saving
• CPC Class Codes: F24F 11/62 characterised by the type of control or by internal processing, e.g. using fuzzy logic, adaptive control or estimation of values
• CPC Class Codes: F24F 11/63 Electronic processing
• CPC Class Codes: F24F 2011/0002 for admittance of outside air
• CPC Class Codes: F24F 2011/0006 using low temperature external supply air to assist cooling
• CPC Class Codes: G05B 13/042 in which a parameter or coefficient is automatically adjusted to optimise the performance
• CPC Class Codes: G05D 23/1917 using digital means
• CPC Class Codes: G05D 23/1931 to control the temperature of one space
• CPC Class Codes: Y02B 30/54 Free-cooling systems

Abstract

Systems and methods to regulate the amount of outdoor air that is introduced into a building. These systems and methods determine the mechanical load requirements based on adaptive control functionality. These systems and methods utilize extremum seeking control logic to vary the flow of outdoor air into the building in response to these load determinations.

Claims

1. A method for operating a system which regulates a damper for varying an amount of outdoor air that is introduced into a building and which regulates a mechanical cooling device that removes heat from air provided to the building, the method comprising:

providing a first operating state of the system by activating the mechanical cooling device and operating the damper using an extremum seeking control to minimize the load on the activated mechanical cooling device;

monitoring an outdoor air temperature, an outdoor air humidity, a return air temperature, and a return air humidity in the first operating state;

computing an outdoor air enthalpy in the first operating state based on the outdoor air temperature and the outdoor air humidity;

computing a first transition boundary between the first operating state and a second operating state of the system, wherein in the second operating state the damper is not controlled using the extremum seeking control and is positioned for providing a maximum amount of outdoor air, wherein computing the first transition boundary comprises determining a first calculated temperature reduced from the monitored return air temperature and determining a first calculated humidity reduced from the monitored return air humidity, the reductions based on at least one of a sensor error and a system model error, wherein computing the first transition boundary further comprises determining a first calculated enthalpy based on the first calculated temperature and the first calculated humidity;

computing a second transition boundary between the first operating state and a third operating state of the system, wherein in the third operating state the damper is not controlled using the extremum seeking control and is positioned for providing a minimum amount of outdoor air, wherein computing the second transition boundary comprises determining a second calculated temperature increased from the monitored return air temperature and determining a second calculated humidity increased from the monitored return air humidity, the increases based on at least one of a sensor error and a system model error, wherein computing the second transition boundary further comprises determining a second calculated enthalpy based on the second calculated temperature and the second calculated humidity;

comparing the outdoor air enthalpy to the first calculated enthalpy and comparing the outdoor air enthalpy to the second calculated enthalpy; and

transitioning the system to one of the second and third operating states of the system based on the enthalpy comparisons.