Abstract
The main purpose of this study is to revitalize the concept of wise and controlled supply of water for domestic, industrial and agricultural applications which facilitate sustainable usage of fresh water resources. As Eritrea is striving to manage its water resources, attention paid primarily to enable water flow control mechanisms in municipal water distribution systems. A table top process control trainer (PCT) was tested through proportional(P), integral (I) and derivative (D) control mechanisms using Ziegler-Nichols second method to evaluate the tuning variables. Applying exclusively P control action, critical period of oscillation (𝑃𝑃𝑐𝑐𝑐𝑐) was estimated as 1.4 sec at proportional band value of 9. P, PI and PID controller performance studies were conducted with tuned variables on the water flow control system at different step disturbances between 20 – 50 % and their corresponding responses were characterized. P controller exhibited faster responses with consistent increments in offset, PI controller recorded highest overshoot values with negligible offset and prolonged settling times. PID controller showed less overshoot values and faster response times than PI but it increased chatter on the control output signal. The study revealed that the system can be safely controlled between 0-80 LPH. If the offset is not a major concern, P controller would be reflected suitable with simple design and minimum expenditure, else PI controller makes offset to zero though it possesses higher settling times. In other words, PID controller is complex using more tuning parameters, need expensive maintenance, and has resulted an intermittent noise in the output signal.
Highlights
Freshwater supply is the main pillar for sustainable economic activities of humankind and an essential element of human life
PID controller tuning methods are classified into closed loop methods such as Ziegler-Nichols method, Tyreus-Luyben method and Damped Oscillation method etc., and Open loop methods like open loop Ziegler Nichols methods, Cohen and Coon method, Minimum error criteria methods etc. [8, 10] there exist very few literatures [11 - 13] about PID tuning of flow control system, in this study, attention paid mainly to evaluate the parameters of PID controller applied for turbine flow control of water assembled in a table top process control trainer
A constant value of amplitude measured exactly at middle of the cycle was clearly seen with distributed samples in case of experiments at proportional band (PPbb) of 9 and its corresponding gain was evaluated as KKcccc = 100/PPbb
Summary
Freshwater supply is the main pillar for sustainable economic activities of humankind and an essential element of human life. Water scarcity and poor water quality are increasingly common across Eritrea, demand for freshwater in rural and urban areas is expected to increase as a result of rapid climate change, population growth, rapid urbanization, economic activity, competition for water and improved standards of living. The removal of electricity from its process of delivery, removes fire and explosion hazards [6, 7] Three types of controllers, proportional, integral and derivative (PID) were developed in 1930s, still the most widely applied industrial controllers. This succeed is a result of many good features of this algorithm such as simplicity, robustness and wide applicability [8]. PID controller tuning methods are classified into closed loop methods such as Ziegler-Nichols method, Tyreus-Luyben method and Damped Oscillation method etc., and Open loop methods like open loop Ziegler Nichols methods, Cohen and Coon method, Minimum error criteria methods etc. [8, 10] there exist very few literatures [11 - 13] about PID tuning of flow control system, in this study, attention paid mainly to evaluate the parameters of PID controller applied for turbine flow control of water assembled in a table top process control trainer
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
