Energy analysis of an air conditioning system using PID and fuzzy logic controllers

Reducing energy consumption and ensuring thermal comfort are two important considerations in designing an air conditioning system. Alternative approach to reduce energy consumption proposed in this study is to use a variable speed compressor. Two control strategies were proposed, which are proportional plus integral plus derivative (PID) and fuzzy logic controllers. An air conditioning system, originally operates on an On/Off control mechanism, was retrofitted to enable the implementation of the controllers. Measurements and computer interface systems were designed and software to implement the controller algorithms was developed using Visual Basic. The system was installed to a thermal environmental room together with a data acquisition system to monitor the temperature of the room, coefficient of performance, energy consumption and energy saving. Measurements were taken during the two hours experimental period at a time interval of five minutes for temperature setpoints of 20, 22 and 24oC with internal heat loads of 0, 500, 700 and 1000W. Each controller was tuned for the best performance. The results indicate that thermal comfort of the room together with significant energy saving can be obtained through a proper selection of controller parameters. Energy analysis shows that PID and fuzzy logic controllers are better than On/Off control mechanism. Generally, fuzzy logic controller is better than PID controllers. However, conventional controllers such as PID or its combinations are still capable of controlling the space temperature with some amount of energy saving but at the expense of the time to tune the controller parameters. A new PID tuning method based on trial and error was therefore proposed. This study shows that using variable speed compressor and choosing suitable control strategy, the space temperature is able to be controlled with significant energy saving.

[1]  Michimasa Kishimoto,et al.  Application of fuzzy control to industrial bioprocesses in Japan , 2002, Fuzzy Sets Syst..

[2]  M.R.M. Rizk,et al.  The effect of membership functions in fuzzy systems on the stability region , 2000, ICECS 2000. 7th IEEE International Conference on Electronics, Circuits and Systems (Cat. No.00EX445).

[3]  T. Senshu,et al.  Annual energy-saving effect of capacity-modulated air conditioner equipped with inverter-driven scroll compressor , 1985 .

[4]  M. Chidambaram,et al.  Design of controllers for unstable first-order plus time delay systems , 1996 .

[5]  Chander P Arora,et al.  Refrigeration and Air Conditioning , 1983 .

[6]  A. Hussu.  Fuzzy control and defuzzification , 1995 .

[7]  A. O'Dwyer,et al.  PID compensation of time delayed processes 1998-2002: a survey , 2003, Proceedings of the 2003 American Control Conference, 2003..

[8]  Ioannis K. Kookos,et al.  PID controller tuning using mathematical programming , 2004 .

[9]  R. Ruelas,et al.  A defuzzification method respecting the fuzzification , 1997, Fuzzy Sets Syst..

[10]  T. Yamamoto,et al.  Development of an energy-saving-oriented variable capacity system heat pump , 1982 .

[11]  George J. Klir,et al.  Fuzzy sets and fuzzy logic , 1995 .

[12]  Savvas A. Tassou,et al.  VARIABLE-SPEED CAPACITY CONTROL IN REFRIGERATION SYSTEMS , 1996 .

[13]  S. Skogestad.  Simple analytic rules for model reduction and PID controller tuning , 2004 .

[14]  Anastasios I. Dounis,et al.  Design of a fuzzy system for living space thermal-comfort regulation , 2001 .

[15]  Savvas A. Tassou,et al.  Comparative performance evaluation of positive displacement compressors in variable-speed refrigeration applications , 1998 .

[16]  J.L.M. Hensen.  On System Simulation for Building Performance Evaluation , 1995 .

[17]  Rainer Palm,et al.  Scaling of fuzzy controllers using the cross-correlation , 1995, IEEE Trans. Fuzzy Syst..

[18]  Stephen Yurkovich,et al.  Fuzzy Control , 1997 .

[19]  Moustafa Elshafei,et al.  Design of a fuzzy servo-controller , 2001, Fuzzy Sets Syst..

[20]  F. Yamada,et al.  Development of air-conditioning control algorithm for building energy saving , 1999, Proceedings of the 1999 IEEE International Conference on Control Applications (Cat. No.99CH36328).

[21]  Marwan Affandi.  Energy saving in an air-conditioning system using an inverter and a temperature-speed controller , 2004 .

[22]  María José del Jesús,et al.  Genetic tuning of fuzzy rule deep structures preserving interpretability and its interaction with fuzzy rule set reduction , 2005, IEEE Transactions on Fuzzy Systems.

[23]  Emadi Ali,et al.  Energy-efficient electric motors , 2005 .

[24]  Jin Wen,et al.  Effect of thermostat time constant on temperature control and energy consumption , 2001, SIcon/01. Sensors for Industry Conference. Proceedings of the First ISA/IEEE. Sensors for Industry Conference (Cat. No.01EX459).

[25]  Yun Li,et al.  PID control system analysis, design, and technology , 2005, IEEE Transactions on Control Systems Technology.

[26]  W. Chen,et al.  Membership Functions Optimization of Fuzzy Control Based on Genetic Algorithms , 1998 .

[27]  Y. Kim,et al.  Modeling on the Performance of an Inverter Driven Scroll Compressor , 1998 .

[28]  Chris P. Underwood,et al.  HVAC Control Systems: Modelling, Analysis and Design , 1999 .

[29]  Yi-Chung Hu,et al.  Mining fuzzy association rules for classification problems , 2002 .

[30]  Shankar P. Bhattacharyya,et al.  PID tuning revisited: guaranteed stability and non-fragility , 2002, Proceedings of the 2002 American Control Conference (IEEE Cat. No.CH37301).

[31]  N. Munro,et al.  PID controllers: recent tuning methods and design to specification , 2002 .

[32]  J. F. Hamilton,et al.  Possible Energy Conservation Through Use of Variable Capacity Compressors , 1974 .

[33]  Gail Brager,et al.  A Better Way to Predict Comfort , 2004 .

[34]  T. Ross.  Fuzzy Logic with Engineering Applications , 1994 .

[35]  P. Fazio,et al.  PI-control of dual duct systems: manual tuning and control loop interaction , 1998 .

[36]  Kenji Tojo,et al.  A Scroll Compressor for Air Conditioners , 1984 .

[37]  R. Padma Sree,et al.  A simple method of tuning PID controllers for stable and unstable FOPTD systems , 2004, Comput. Chem. Eng..

[38]  J. F. Nicol,et al.  Developing an adaptive control algorithm for Europe , 2002 .

[39]  Y. Shi,et al.  Effects of different slopes of membership functions on the fuzzy control of DC-DC converters , 2000, Proceedings IPEMC 2000. Third International Power Electronics and Motion Control Conference (IEEE Cat. No.00EX435).

[40]  Haji Hassan Masjuki,et al.  Potential electricity savings by implementing minimum energy efficiency standards for room air conditioners in Malaysia , 2001 .

[41]  Mary M. Bourke.  Self-learning predictive control using relational-based fuzzy logic , 1996 .

[42]  Ibrahim Kaya,et al.  IMC based automatic tuning method for PID controllers in a Smith predictor configuration , 2004, Comput. Chem. Eng..

[43]  Chung-hoi Philip Yu.  A study of energy use for ventilation and air-conditioning systems in Hong Kong , 2001 .

[44]  Young Chul Kim,et al.  Performance analysis on a multi-type inverter air conditioner , 2001 .

[45]  Thomas F. Edgar,et al.  Process Dynamics and Control , 1989 .

[46]  Leon Reznik.  Evolution of fuzzy controller design , 1997, Proceedings of 6th International Fuzzy Systems Conference.

[47]  Nabil Derbel,et al.  Fuzzy control of robot manipulators , 2002 .

[48]  B. M. Mohan,et al.  Analytical structures and analysis of the simplest fuzzy PI controllers , 2002, Autom..

[49]  Dr. Hans Hellendoorn,et al.  An Introduction to Fuzzy Control , 1996, Springer Berlin Heidelberg.

[50]  R. K. Suri,et al.  Programmable thermostat for energy saving , 2001 .

[51]  Tore Hägglund,et al.  Automatic Tuning of Pid Controllers , 1988 .

[52]  A. G. Sreenatha,et al.  Fuzzy logic controller for position control of flexible structures , 2002 .

[53]  Stanko Strmčnik,et al.  A new PID controller tuning method based on multiple integrations , 1999 .

[54]  Albert T.P. So,et al.  New HVAC control by system identification , 1995 .

[55]  Hisao Ishibuchi,et al.  Performance evaluation of fuzzy partitions with different fuzzification grades , 2002, 2002 IEEE World Congress on Computational Intelligence. 2002 IEEE International Conference on Fuzzy Systems. FUZZ-IEEE'02. Proceedings (Cat. No.02CH37291).

[56]  Leonid Reznik,et al.  PID plus fuzzy controller structures as a design base for industrial applications , 2000 .

[58]  Teresa Orlowska-Kowalska,et al.  The influence of parameters and structure of PI-type fuzzy-logic controller on DC drive system dynamics , 2002, Fuzzy Sets Syst..

[59]  Ricardo Nicolau Nassar Koury,et al.  Numerical simulation of a variable speed refrigeration system , 2001 .

[60]  Aidan O'Dwyer,et al.  Handbook of PI and PID controller tuning rules , 2003 .

[61]  M. R. Katebi,et al.  Controller tuning methods for industrial boilers , 2000, 2000 26th Annual Conference of the IEEE Industrial Electronics Society. IECON 2000. 2000 IEEE International Conference on Industrial Electronics, Control and Instrumentation. 21st Century Technologies.

[62]  Aytekin Bagis,et al.  Determining fuzzy membership functions with tabu search - an application to control , 2003, Fuzzy Sets Syst..

[63]  T. Fukuda,et al.  Self-tuning fuzzy modeling with adaptive membership function, rules, and hierarchical structure based on genetic algorithm , 1995 .

[64]  Shankar P. Bhattacharyya,et al.  PID Controllers for Time Delay Systems , 2004 .

[65]  Mohammad Hassan Moradi,et al.  New techniques for PID controller design , 2003, Proceedings of 2003 IEEE Conference on Control Applications, 2003. CCA 2003..

[66]  C. Underwood,et al.  ANALYSING MULTIVARIABLE CONTROL OF REFRIGERATION PLANT USING MATLAB/SIMULINK , 2001 .

[67]  George A. Perdikaris.  Computer Controlled Systems: Theory and Applications , 1991 .

[68]  Michael A. Humphreys,et al.  ADAPTIVE THERMAL COMFORT AND SUSTAINABLE THERMAL STANDARDS FOR BUILDINGS , 2002 .

[69]  Xavier Blasco,et al.  OPTIMAL PID TUNING WITH GENETIC ALGORITHMS FOR NON LINEAR PROCESS MODELS , 2002 .

[70]  Manabu Sakai,et al.  On the Superior Dynamic Behavior of a Variable Rotating Speed Scroll Compressor , 1988 .

[71]  C. G. Nesler.  Automated controller tuning for HVAC applications , 1986 .

[72]  R. Schumann.  Digital parameter-adaptive control of an air-conditioning plant , 1982, Autom..

[73]  Shiming Deng.  The application of feedforward control in a direct expansion (DX) air conditioning plant , 2002 .

[74]  B. Bose,et al.  Evaluation of membership functions for fuzzy logic controlled induction motor drive , 2002, IEEE 2002 28th Annual Conference of the Industrial Electronics Society. IECON 02.

[75]  Kiam Heong Ang,et al.  PID control system analysis and design , 2006, IEEE Control Systems.

[76]  Jin S. Lee,et al.  A class of hierarchical fuzzy systems with constraints on the fuzzy rules , 2005, IEEE Transactions on Fuzzy Systems.

[77]  H. N. Lam,et al.  Using genetic algorithms to optimize controller parameters for HVAC systems , 1997 .

[78]  Dogan Ibrahim.  Microcontroller-Based Temperature Monitoring and Control , 2002 .

[79]  Shan K. Wang,et al.  Handbook of Air Conditioning and Refrigeration , 1993 .

[80]  C. T. Wu,et al.  Performance of fixed, air-side economizer, and neural network demand-controlled ventilation in CAV systems , 1998 .

[81]  Mohammed S. Imbabi.  Computer validation of scale model tests for building energy simulation , 1990 .

[82]  Keck Voon Ling,et al.  Expert control of air-conditioning plant , 1994, Autom..

[83]  Bengt Lennartson,et al.  Evaluation and simple tuning of PID controllers with high-frequency robustness , 2006 .

[84]  D. Kolokotsa,et al.  Advanced fuzzy logic controllers design and evaluation for buildings’ occupants thermal–visual comfort and indoor air quality satisfaction , 2001 .

[85]  Rajni V. Patel,et al.  Adaptive control of multivariable thermal processes in HVAC systems , 2000 .

[86]  Jacek M. Zurada,et al.  Data-driven linguistic modeling using relational fuzzy rules , 2003, IEEE Trans. Fuzzy Syst..

[87]  M. G. McArdle,et al.  A digital PID speed controller for a diesel generating set , 2003, 2003 IEEE Power Engineering Society General Meeting (IEEE Cat. No.03CH37491).

[88]  P. A. Stoecker,et al.  Microcomputer Control of Thermal and Mechanical Systems , 1988 .

[89]  S. Himavathi,et al.  New membership functions for effective design and implementation of fuzzy systems , 2001, IEEE Trans. Syst. Man Cybern. Part A.

[90]  Lu-Sa Su,et al.  Digital controller - its design techniques , 1994, Conference Proceedings. 10th Anniversary. IMTC/94. Advanced Technologies in I & M. 1994 IEEE Instrumentation and Measurement Technolgy Conference (Cat. No.94CH3424-9).

[91]  Magnus Mossberg,et al.  Iterative feedback tuning of PID parameters: comparison with classical tuning rules , 2003 .

[92]  Mattheos Santamouris.  Solar thermal technologies for buildings : the state of the art , 2003 .

[93]  Anthony Green,et al.  Heuristic design of a fuzzy controller for a flexible robot , 2006, IEEE Transactions on Control Systems Technology.

[94]  Jung Ho Kim,et al.  An application of fuzzy logic to control the refrigerant distribution for the multi-type air conditioner , 1999, FUZZ-IEEE'99. 1999 IEEE International Fuzzy Systems. Conference Proceedings (Cat. No.99CH36315).

[95]  K. I. Krakow,et al.  Analytical determination of PID coefficients for temperature and humidity control during cooling and dehumidifying by compressor and evaporator fan speed variation , 1995 .

[96]  M. Gopal,et al.  Control Systems: Principles and Design , 2006 .

[97]  Madan M. Gupta,et al.  Fuzzy Sets, Fuzzy Logic, and Fuzzy Systems , 2003 .

[98]  K. Åström,et al.  Revisiting The Ziegler‐Nichols Tuning Rules For Pi Control , 2002 .

[99]  J. F. Kreider,et al.  Experimental results of a predictive neural network HVAC controller , 1998 .

[100]  Eduardo A. B. da Silva,et al.  Digital Signal Processing: System Analysis and Design , 2002 .

[101]  S. D. Probert,et al.  Performance instability of a refrigerator with its evaporator controlled by a thermostatic expansion-valve , 2001 .

[102]  Abraham Kandel,et al.  On direct construction of fuzzy systems , 2000, Fuzzy Sets Syst..

[103]  Thierry Fraichard,et al.  Fuzzy control to drive car-like vehicles , 2001, Robotics Auton. Syst..

[104]  S. Yasin.  Systematic Methods for the Design of a Class of Fuzzy Logic Controllers , 2002 .

[105]  P. S. Fruehauf,et al.  PID tuning: It`s the method, not the rules , 1994 .

[106]  İlyas Eker,et al.  Fuzzy logic control to be conventional method , 2006 .

[107]  Savvas A. Tassou,et al.  Investigation into Alternative Compressor Technologies for Variable Speed Refrigeration Applications , 1994 .

[108]  J. Niu,et al.  Numerical procedure for predicting annual energy consumption of the under-floor air distribution system , 2006 .