FUZZY-PID CONTROLLER APPLIED TO A REFRIGERATION SYSTEM

A refrigeration system exhibits a dynamic behavior on which the variables are interdependent and subjected to oscillation, hence, implicating necessity of changes on operating conditions and undesirable energy expenses. These characteristics ratify the importance of adequate dimensioning and equipment selection to find pre-defined operating conditions such as, the maximum cooling capacity and the evaporating and condensing temperatures. The application of fuzzy control in industrial processes is growing fast in the last decades, mainly in processes whose first principle models require complex methods to be simulated. In these cases, the fuzzy controllers’ capacity of acting correctly based only on expert knowledge and on the capacity of inter-relating all the variables of the process are attractive features. This work presents the experimental development and evaluation of fuzzy-PID controllers for the maintenance of the evaporating temperature in a chiller. The system was submitted to load and set-point disturbances accomplishing an analysis based upon error parameters and transient response. The results showed that fuzzy controllers were adapted satisfactorily.

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Grasshopper Algorithm Optimized Fractional Order Fuzzy PID Frequency Controller for Hybrid Power Systems

Recent Advances in Electrical & Electronic Engineering (Formerly Recent Patents on Electrical & Electronic Engineering) ◽

10.2174/2352096511666180717142058 ◽

2019 ◽

Vol 12 (6) ◽

pp. 519-531

Author(s):

Deepak Kumar Lal ◽

Ajit Kumar Barisal

Keyword(s):

Power Systems ◽

Power System ◽

Fractional Order ◽

Pid Controller ◽

Load Frequency Control ◽

Pid Controllers ◽

Fuzzy Pid ◽

Fuzzy Pid Controller ◽

Hybrid Power ◽

Increasing Demand

Background: Due to the increasing demand for the electrical power and limitations of conventional energy to produce electricity. Methods: Now the Microgrid (MG) system based on alternative energy sources are used to provide electrical energy to fulfill the increasing demand. The power system frequency deviates from its nominal value when the generation differs the load demand. The paper presents, Load Frequency Control (LFC) of a hybrid power structure consisting of a reheat turbine thermal unit, hydropower generation unit and Distributed Generation (DG) resources. Results: The execution of the proposed fractional order Fuzzy proportional-integral-derivative (FO Fuzzy PID) controller is explored by comparing the results with different types of controllers such as PID, fractional order PID (FOPID) and Fuzzy PID controllers. The controller parameters are optimized with a novel application of Grasshopper Optimization Algorithm (GOA). The robustness of the proposed FO Fuzzy PID controller towards different loading, Step Load Perturbations (SLP) and random step change of wind power is tested. Further, the study is extended to an AC microgrid integrated three region thermal power systems. Conclusion: The performed time domain simulations results demonstrate the effectiveness of the proposed FO Fuzzy PID controller and show that it has better performance than that of PID, FOPID and Fuzzy PID controllers. The suggested approach is reached out to the more practical multi-region power system. Thus, the worthiness and adequacy of the proposed technique are verified effectively.

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Performance Analysis on a Solar-Driven Air-Cooled Ejector Refrigeration System for Air-Conditioning Using Ammonia as Refrigerant

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.501-504.2282 ◽

2014 ◽

Vol 501-504 ◽

pp. 2282-2287 ◽

Cited By ~ 1

Author(s):

Yu Hang Liao ◽

Wei Lu ◽

Lie Pan

Keyword(s):

Performance Analysis ◽

Solar Irradiance ◽

Air Conditioning ◽

Cooling Capacity ◽

Climatic Conditions ◽

Operating Conditions ◽

Refrigeration System ◽

Outdoor Temperature ◽

Indoor Temperature ◽

Changing Trend

The performance of a solar-driven air-cooled ejector refrigeration system using ammonia as refrigerant with rated cooling capacity of 10.5kW was analyzed for air-conditioning purpose. The cooling capacity of the proposed system increases with the rising of indoor temperature and enhancement of solar irradiance, while decreases with the rising of outdoor temperature. The COP has similar changing trend with that of the cooling capacity except that it increases rapidly with the enhancement of solar irradiance firstlyand then become stable by and large after solar irradiance exceeding a certain value. The cooling capacity is 6.3~52kW and the COP 0.06~0.11 under the normal operating conditions with indoor temperature over 27, outdoor temperature below 38°C and solar irradiance surpassing 500 W/m2. The proposed system can match the climatic conditions in air-conditioning season of Nanning, a typical city in hot summer and warm winter region.

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Evaporator Frosting in Refrigerating Appliances: Fundamentals and Applications

Energies ◽

10.3390/en14185991 ◽

2021 ◽

Vol 14 (18) ◽

pp. 5991

Author(s):

Christian J. L. Hermes ◽

Joel Boeng ◽

Diogo L. da Silva ◽

Fernando T. Knabben ◽

Andrew D. Sommers

Keyword(s):

First Principles ◽

Simulation Models ◽

Cooling Capacity ◽

Operating Conditions ◽

Coefficient Of Performance ◽

Trial And Error ◽

Refrigeration System ◽

Duty Cycles ◽

Transfer Principles ◽

Frost Layer

Modern refrigerators are equipped with fan-supplied evaporators often tailor-made to mitigate the impacts of frost accretion, not only in terms of frost blocking, which depletes the cooling capacity and therefore the refrigerator coefficient of performance (COP), but also to allow optimal defrosting, thereby avoiding the undesired consequences of condensate retention and additional thermal loads. Evaporator design for frosting conditions can be done either empirically through trial-and-error approaches or using simulation models suitable to predict the distribution of the frost mass along the finned coil. Albeit the former is mandatory for robustness verification prior to product approval, it has been advocated that the latter speeds up the design process and reduces the costs of the engineering undertaking. Therefore, this article is aimed at summarizing the required foundations for the design of efficient evaporators and defrosting systems with minimized performance impacts due to frosting. The thermodynamics, and the heat and mass transfer principles involved in the frost nucleation, growth, and densification phenomena are presented. The thermophysical properties of frost, such as density and thermal conductivity, are discussed, and their relationship with refrigeration operating conditions are established. A first-principles model is presented to predict the growth of the frost layer on the evaporator surface as a function of geometric and operating conditions. The relation between the microscopic properties of frost and their macroscopic effects on the evaporator thermo-hydraulic performance is established and confirmed with experimental evidence. Furthermore, different defrost strategies are compared, and the concept of optimal defrost is formulated. Finally, the results are used to analyze the efficiency of the defrost operation based on the net cooling capacity of the refrigeration system for different duty cycles and evaporator geometries.

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Control of Hybrid Stepping Motor Drive Using Computational Verb PID Controllers

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.853.428 ◽

2013 ◽

Vol 853 ◽

pp. 428-434 ◽

Cited By ~ 1

Author(s):

Xue Qin Zheng

Keyword(s):

Pid Controller ◽

Pid Controllers ◽

Motor Drive ◽

Stepping Motor ◽

Fuzzy Pid ◽

Load Variations ◽

Fuzzy Pid Controller ◽

Hybrid Stepping Motor ◽

Simulation Results ◽

Low Performance

Thanks to the development of microprocessors, hybrid stepping motors have been widely used in many areas where they perform positioning operations. However, the stepping motor suffers from system variations, low performance and lack of adaptability to load variations, which slow down their responding speed of high-precision positioning operations. In this paper, a computational verb PID controller is proposed to control the position of a stepping motor drive. The simulation results show that the computational verb PID controller has better performances than conventional and fuzzy PID controllers. The simulation results also show that the responding speed and positioning accuracy of the controlled hybrid stepping motor were greatly improved. Computational verb PID controller has much less computational complexity than fuzzy PID controller.

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Effect of Hydrofluorocarbons and Hydrofluoroolefins in a Household Refrigerator as a Substitute for R134a

Materials Science Forum ◽

10.4028/www.scientific.net/msf.969.199 ◽

2019 ◽

Vol 969 ◽

pp. 199-204

Author(s):

Shaik Mohammad Hasheer ◽

Kolla Srinivas

Keyword(s):

Cooling Capacity ◽

Operating Conditions ◽

Coefficient Of Performance ◽

Condensation Temperature ◽

Outlet Temperature ◽

Refrigeration System ◽

Volumetric Cooling ◽

Work Done ◽

Theoretical Results ◽

Hfc 152A

Now a days R134a can be used in domestic refrigerators and in air conditioning of automobiles. As per Kyoto protocol the usage of R134a is restricted due to their higher GWP value. The GWP value of this refrigerant is around 1430. So in this article, thermodynamic analysis of HFC-152a, HFO refrigerants-1234ze(E) and 1234yf was done in a household refrigeration system as direct substitute to HFC-134a.The performance of the household refrigerator was compared in terms of outlet temperature of the compressor, volumetric cooling capacity (VCC), refrigeration effect, work done by the compressor and coefficient of performance (COP). The entire analysis is carried out at various operating conditions of condenser and evaporator temperatures i.e. condensation temperature of 25°C,35°C & 45°C and evaporating temperatures ranging between −20°C to 10°C.From the theoretical results, it can be concluded that R1234yf can be used as a direct substitute to R134a.

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An Optimal Fuzzy PID Controller Design Based on Conventional PID Control and Nonlinear Factors

Applied Sciences ◽

10.3390/app9061224 ◽

2019 ◽

Vol 9 (6) ◽

pp. 1224 ◽

Cited By ~ 5

Author(s):

Chun-Tang Chao ◽

Nana Sutarna ◽

Juing-Shian Chiou ◽

Chi-Jo Wang

Keyword(s):

Pid Control ◽

Pid Controller ◽

Controller Design ◽

Pid Controllers ◽

Initial Population ◽

Fuzzy Pid ◽

Proportional Integral Derivative ◽

Fuzzy Logic Controllers ◽

Fuzzy Pid Controller ◽

Pid Controller Design

This paper proposes an optimal fuzzy proportional–integral–derivative (PID) controller design based on conventional PID control and nonlinear factors. With the equivalence between fuzzy logic controllers (FLCs) and conventional PID controllers, a conventional PID controller design can be rapidly transformed into an equivalent FLC by defining the operating ranges of the input/output of the controller. The proposed nonlinear factors can further tune the nonlinearity of the membership functions (MFs) distributed in the operating ranges. In this manner, a fuzzy PID controller can be developed with less parameters and optimized by using the genetic algorithm (GA). In addition, the aforementioned equivalent FLC can act as one individual in the initial population of GA, and significantly enhances the GA efficiency. Simulation results demonstrate the feasibility of this technique. This resulted in an optimal fuzzy PID controller design with only eight parameters with a concise controller structure, and most importantly, the optimal fuzzy PID controller design is now more systematic.

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Research on the Application of the Fuzzy Control Algrithm in the HAPC System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.220-223.157 ◽

2012 ◽

Vol 220-223 ◽

pp. 157-160

Author(s):

Jing Qing Ma ◽

Hai Bo Chen

Keyword(s):

Dynamic Response ◽

Pid Controller ◽

Position Control ◽

Pid Controllers ◽

Control Methods ◽

Fuzzy Pid ◽

Fuzzy Pid Controller ◽

Main Factors ◽

High Control ◽

Control Accuracy

The HAPC(Hydraulic Automatic Position Control) requires quick dynamic response and high control accuracy. Based on the research of the HAPC system, I build the HAPC mathematical model, then design both the Conventional PID controller and fuzzy PID controllers, simulate the two control methods using the MATLAB software, analyze the main factors which influence the results. The simulation results show that the fuzzy PID controller has the better effect in the dynamic response and the control accuracy than the former.

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Fuzzy PID Control for Fast-Steering Mirror System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.568-570.1026 ◽

2014 ◽

Vol 568-570 ◽

pp. 1026-1030

Author(s):

Xue Jin Bai ◽

Yong Ming Qiao

Keyword(s):

Control System ◽

Transient Process ◽

Pid Control ◽

Pid Controller ◽

High Speed ◽

Mirror System ◽

Pid Controllers ◽

Fuzzy Pid ◽

Fuzzy Pid Control ◽

Fuzzy Pid Controller

Fast-steering mirror system demands higher accuracy and fast responding speed to track targets, but the conventional PID controllers cannot meet the demands. Instead, the fuzzy PID control can greatly improve the capturing and tracking capacities to high-speed dynamic targets. So we apply the fuzzy-PID controller in the positioning loop of the stabilized system, not only improving the transient process of the control system and decreasing the overshoot, but also enhancing the accuracy of tracking stabilization and response. At the end, simulations were performed to test the effectiveness of this method through the MATLAB platform.

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Precision contouring control of five degree of freedom robot manipulators with uncertainty

International Journal of Advanced Robotic Systems ◽

10.1177/1729881416682703 ◽

2016 ◽

Vol 14 (1) ◽

pp. 172988141668270 ◽

Cited By ~ 3

Author(s):

Thanana Nuchkrua ◽

Shyh-Leh Chen

Keyword(s):

Pid Controller ◽

Robot Manipulators ◽

Operating Conditions ◽

Degree Of Freedom ◽

Control Performance ◽

Fuzzy Pid ◽

Proportional Integral Derivative ◽

Excellent Performance ◽

Fuzzy Pid Controller ◽

Contouring Control

In this article, we apply a result in equivalent errors to a contouring control problem of five degree of freedom robot manipulators. The proposed technique, fuzzy Proportional Integral Derivative (PID) with the robust extended Kalman filter, is employed to stabilize the dynamic of equivalent errors of robot manipulators. The shape of membership functions and rules of fuzzy PID controller are tuned following operating conditions that make the control performance to improve significantly. A desired path in terms of the position of the end-effector of the robot manipulators is described in generalized coordinates defined by the dynamic of equivalent. The simulation and experimental results demonstrate the excellent performance of the proposed technique.

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