FUZZY LOGIC CONTROLLER DESIGN FOR STAGED HEATING AND VENTILATING SYSTEMS

Conventional stage controllers (CSC) for interior environment control of agricultural facilities are prevalent and well suited for slowly varying loads, smaller facilities with few stages of control, and in cases where "discrete proportional control" is deemed adequate. Ad hoc implementation schemes for using the same CSC over a range in size of building heating and ventilating systems, from one heating and cooling stage to many, are practiced in the industry. A fuzzy logic controller (FLC) was developed to satisfy a broad spectrum of installation sizes without any modification. Principles for designing an environment controller that can mimic CSC behavior over a broad range of system size were applied. By adjusting a single additional input this controller provides users with a trade-off between energy use and control precision. Simulations were conducted using the same FLC in a greenhouse and a broiler house; these two examples were selected for their considerable difference in magnitude of energy transfer and loads. Disturbances investigated included: variations in outside temperature, internal heat load (or solar load), and step changes in set point temperature. FLC system responses are compared with a representative CSC for stability, overshoot and mean square error from set point temperature. The FLC was able to keep the root-mean-square errors to 1.0 to 4.0°C, depending on different energy use settings. The FLC provided useful improvements in performance over a CSC, and is readily implemented in modern electronic controllers with floating point arithmetic capability. Keywords. Broiler, Energy conservation, Environment control, Greenhouse, HVAC, Knowledge based systems engineering, Simulation.

[1]  Konstantinos G. Arvanitis,et al.  A learning technique for a general purpose optimizer , 2000 .

[2]  T. F. Burks,et al.  Development of the design climatic data for the 1997 ASHRAE Handbook - Fundamentals , 2000 .

[3]  Michael B. Timmons,et al.  Relative Humidity as a Ventilation Control Parameter in Broiler Housing , 1987 .

[4]  D. G. Colliver,et al.  New weather data for energy calculations , 1999 .

[5]  Louis D. Albright,et al.  Environment Control for Animals and Plants , 1991 .

[6]  Simon Parsons,et al.  Soft computing: fuzzy logic, neural networks and distributed artificial intelligence by F. Aminzadeh and M. Jamshidi (Eds.), PTR Prentice Hall, Englewood Cliffs, NJ, pp 301, ISBN 0-13-146234-2 , 1996, Knowl. Eng. Rev..

[7]  Nick Sigrimis,et al.  Advances in greenhouse environment control , 2000 .

[8]  Nick Sigrimis,et al.  Design Parameters for Fuzzy-Based Control of Agricultural Ventilation Systems , 1998 .

[9]  L. S. Marsh,et al.  ECONOMICALLY OPTIMUM DAY TEMPERATURES FOR GREENHOUSE HYDROPONIC LETTUCE PRODUCTION PART II: RESULTS AND SIMULATIONS , 1991 .

[10]  Richard S Gates,et al.  Sequences of extreme temperature and humidity for design calculations , 1998 .

[11]  L. S. Marsh,et al.  Economically optimum day temperatures for greenhouse hydroponic lettuce production. I. A computer model , 1991 .

[12]  Richard S Gates,et al.  Knowledge-based control systems for single stem rose production. Part I : Systems analysis and design , 1998 .

[13]  Konstantinos G. Arvanitis,et al.  Synergism of high and low level systems for the efficient management of greenhouses , 2000 .

[14]  Richard S Gates,et al.  KNOWLEDGE-BASED CONTROL SYSTEMS FOR SINGLE STEM ROSE PRODUCTION — PART II: IMPLEMENTATION AND FIELD EVALUATION , 1998 .

[15]  Konstantinos G. Arvanitis,et al.  Computer Integrated Management and Intelligent Control of Greenhouses , 2002 .

[16]  Michael B. Timmons,et al.  Economic Optimization of Tom Turkey Production , 1989 .

[17]  Daniel Berckmans,et al.  Development of new control techniques for the ventilation and heating of livestock buildings , 1986 .

[18]  Nick Sigrimis,et al.  A linear model for greenhouse control , 1996 .

[19]  Richard S Gates,et al.  Design of switching control systems for ventilated greenhouses , 1996 .

[20]  Guanrong Chen,et al.  Fuzzy PID control of a flexible-joint robot arm with uncertainties from time-varying loads , 1997, IEEE Trans. Control. Syst. Technol..

[21]  George W. Cole.  The Application of Control Systems Theory to the Analysis of Ventilated Animal Housing Environments , 1980 .

[22]  Michael B. Timmons,et al.  ECONOMIC OPTIMIZATION OF BROILER PRODUCTION. , 1986 .

[23]  Richard S Gates,et al.  Diagnostic hardware/software system for environment controllers , 1995 .

[24]  Michael B. Timmons,et al.  Simulation analysis of a new temperature control method for poultry housing , 1995 .

[25]  Douglas G. Overhults,et al.  TRANSIENT OVERVOLTAGE TESTING OF ENVIRONMENTAL CONTROLLERS , 1992 .

[26]  Douglas G. Overhults,et al.  Mechanical Backup Systems for Electronic Environmental Controllers , 1992 .

[27]  Nick Sigrimis,et al.  Energy saving in greenhouses using temperature integration: a simulation survey , 2000 .

[28]  Douglas G. Overhults,et al.  Constant velocity air inlet controller , 1991 .

[29]  Douglas G. Overhults,et al.  Field Calibration of a Transient Model for Broiler Misting , 1992 .