ကိုထြန္းသူ

"သေဘ္ာ က VFD ဆိုတဲ႔ Variable frequency drive (၁)" Reference, thanks and image credit to : (1) Bartos, Frank J. (Sep. 1, 2004). "AC Drives Stay Vital for the 21st Century". Control Engineering (Reed Business Information)., (2) Cleaveland, Peter (Nov. 1, 2007). "AC Adjustable Speed Drives". Control Engineering (Reed Business Information)., (3) "Power Electronics and Motor Drives" : Advances and Trends. Amsterdam: Academic. ISBN 978-0-12-088405-6., Bartos, Frank J. (Sep. 1, 2004). (4) "AC Drives Stay Vital for the 21st Century". Control Engineering (Reed Business Information)., Eisenbrown, Robert E. (May 18, 2008). (5) "AC Drives, Historical and Future Perspective of Innovation and Growth". Keynote Presentation for the 25th Anniversary of The Wisconsin Electric Machines and Power Electronics Consortium (WEMPEC). University of Wisconsin, Madison, WI, USA. Remark : All references and images herein this page are ...

"Basic Control Theory - (6) - Computers in Control" Reference, thanks and image credit to : Steam Engineering Tutorial, Remark : All publications and images herein this page are for use of educational purpose only. The owner of this page is not responsible for the consequences in case of violation to copyright, trademark, patent or other intellectual property rights of any third party.   ဟိုးအရင္က၊ basic PID functions ေတြ၊ ေဆာင္ရြက္နိဳင္ရန္၊ flaps နဲ႔ nozzles ေတြ၊ ထည္႔သြင္း တတ္ဆင္ထားတဲ႔၊ pneumatic controllers ေတြကို၊ stand-alone single loop controllers ေတြအၿဖစ္၊ အသံုးၿပဳခဲ႔ႀကပါတယ္။ individually connected အေနနဲ႔၊  စကၠဴ အသံုးၿပဳၿပီး၊ local circular chart recorders ေတြ၊  တတ္ဆင္၊ အသံုးၿပဳထားတာလည္း၊ ၿဖစ္ပါတယ္။ ေဘးအနၱရာယ္ရိွတဲ႔၊ hazardous locations ေနရာေတြမွာ၊ အလြယ္တကူ၊ မီးေလာင္ကၽြမ္းမွဴ၊ မၿဖစ္ေပါါေစရန္၊ intrinsic safety အေနနဲ႔၊ အသံုးၿပဳခဲ႔တဲ႔၊ pneumatic controllers ေတြကို၊ တခါတရံ၊ ေတြ႔နိဳင္ပါေသးတယ္။ ေနာက္ပိုင္းမွာေတာ႔၊ pneumatic controllers ေတြအစား၊...

"Basic Control Theory - (5) - Good Control" Reference, thanks and image credit to : Steam Engineering Tutorial, Remark : All publications and images herein this page are for use of educational purpose only. The owner of this page is not responsible for the consequences in case of violation to copyright, trademark, patent or other intellectual property rights of any third party.   "Controller" controller ေတြကို၊ (i) dynamic of process, (ii) type of response နဲ႔၊ (ii) accuracy of control ဆိုတဲ႔၊ အခၽက္ (၃) ခၽက္အေပါါ၊ မူတည္ၿပီး၊ ေရြးခၽယ္ရန္၊ လိုအပ္ပါတယ္။ ဒါ႔အၿပင္၊ process ဒါမွမဟုတ္၊ plant တခုလံုးရဲ႕၊ ေဘးအနၱရာယ္၊ ကင္းရွင္းေရး safety ဟာ၊ အေရးႀကီးတဲ႔အတြက္၊ process ဒါမွမဟုတ္၊ plant တခုလံုး၊ ထိမ္းေႀကာင္းေပးမယ္႔၊ controllers ေတြဟာ၊ အေရးႀကီးတဲ႔၊ အစိတ္အပိုင္းေတြလည္း၊ ၿဖစ္ပါတယ္။ on/ off control သာ၊ လိုအပ္မယ္႔ applications ေတြမွာေတာ႔၊ controller ေတြ၊ တတ္ဆင္အသံုးၿပဳရန္၊ 'မလိုအပ္' တဲ႔အတြက္၊ sensors ေတြနဲ႔ relays ေတြ၊ အသံုးၿပဳၿပီး၊ process ကို၊ ထိမ္းေ...

 "Basic Control Theory - (4) - Selection of controls" Reference, thanks and image credit to : Steam Engineering Tutorial, Remark : All publications and images herein this page are for use of educational purpose only. The owner of this page is not responsible for the consequences in case of violation to copyright, trademark, patent or other intellectual property rights of any third party.  "Selection of controls" process မွာ၊ တတ္ဆင္အသံုးၿပဳမယ္႔၊ controllers, valves, actuators နဲ႔ sensors အစရိွတဲ႔၊ components ေတြဟာ၊ safety, stability နဲ႔၊ accuracy ေတြ၊ ရိွရန္၊ လိုအပ္ပါတယ္။ components ေတြ၊ ေရြးခၽယ္တဲ႔အခါ၊ temperature, pressure, level, flow အစရိွတဲ႔၊ property ေတြ အထဲမွ၊ မည္သည္႔ property အား၊ controlled အေနၿဖင္႔ ထိမ္းေႀကာင္းမည္႔ အခၽက္ကို၊ အရင္ဆံုး စဥ္းစားရမွာ၊ ၿဖစ္ပါတယ္။ ဒါ႔အၿပင္ controlled medium ရဲ႕၊ ရုပ္ဂုဏ္သတၱိ physical properties ေတြနဲ႔၊ ေဘးအနၱရယ္ ကင္းရွင္းမွဴဆိုင္ရာ safety features ေတြကိုလည္း၊ အေသအၿခာ သိထားရန္၊ လိုအပ္ပါတယ္။ pressure control အတြက္၊ ...

"Basic Control Theory - (3) - Control Loops and Dynamics Process" Reference, thanks and image credit to : Steam Engineering Tutorial, Remark : All publications and images herein this page are for use of educational purpose only. The owner of this page is not responsible for the consequences in case of violation to copyright, trademark, patent or other intellectual property rights of any third party.  Control Loops နဲ႔ Dynamics process အပိုင္း၊ မဆက္ခင္၊ Time constant, Hunting, Lag, Range ability နဲ႔၊ Turn-down ratio အစရိွတဲ႔၊ အေခါါအေဝါါ၊ အသံုးအနံွဳးေတြကို၊ ေဖာ္ၿပပါဦးမယ္။ 'Time constant' -  load ေၿပာင္းလဲစဥ္၊ initial value မွ၊ final value အထိ၊ ေရာက္ရိွ လာေစရန္၊ controller ဟာ၊ အခၽိန္အတိုင္းအတာ တခု၊ ယူကာ၊ ေဆာင္ရြက္ရၿပီး၊ Time constant လို႔၊ ေခါါပါတယ္။ Time constant ဟာ၊ load ရဲ႕၊  initial value မွ၊ 63.2% ခန္႔ အထိ၊  အခၽိန္ 'ယူ' ပါတယ္။ load ေၿပာင္းလဲၿပီး၊ controller မွ၊ valve ကို၊ ၿပန္ 'ပြင္႔' ေစတဲ႔အခါ၊ valve movement ရဲ႕၊ 63.2% အထိ၊ အခၽိ...