The purpose of Turbine Load Rejecti** Test is to verify and dem**strate the governor functi** to sustain a load rejecti** in order to prevent the turbine from overspeed tripping, steady speed c**trol at no-load operati** and remain in service without any adverse effect to the turbine. The test requires skillful and appropriate operati** not **ly for turbine , but also for boiler and its auxiliaries.
Items to be c**firmed for Load Rejecti** Test 1-Turbine main valves 2-GV no load valve positi** 3-Lube oil pump auto start test 4-Protective device test 5-Valve transfer from MSV mode to GV mode 6-Overspeed tripping point (111% speed) 7-OPC (Overspeed Protecti** C**troller) functi** 8-Exclusi** of Interlocks (Turbine Trip due to Boiler Trip)
TEST PROCEDURE
*Before Load Rejecti** Test (**e hour) 1-C**firm steady c**diti** of load operati** 2-Perform mechanical Over Speed Oil trip Test 3-Perform Lub. oil pump auto start test 4-change over unit auxiliary bus from unit auxiliary transformer to start up transformer.
*Before Load Rejecti** Test (30 minutes) 1-C**firm that level of( C**denser , De aerator and HP/LP feed water heaters are ****** range 2-c**firm that AVR in automatic mode 3-C**firm that HP and LP Turbine bypass ( valves and Sprays ) are in automatic mode
*Before Load Rejecti** Test (10 minutes) 1-c**firm the appointed time with the load dispatcher 2- Exclude the interlock of (Turbine Trip due to Boiler Trip)
*Before Load Rejecti** Test (0 minute) 1-Open Circuit breaker of the Generator. 2-If the Overspeed trip device doesn't operate c**trary to expectati**s even when the turbine speed exceeds 111% of the rated speed , Trip immediately the turbine. 3-All observers shall read and record "Maximum or Minimum" of the measuring objects during transient c**diti**
After Load Rejecti** Pay attenti** to the following points and see that there is no distincti** about them. -Turbine speed -Rotor Positi** & Vibrati** -BRG temp. and Vibrati** -C**denser Vacuum and hotwell level
Stabilizati** -Stabilizati** will be judged when turbine speed is stabilized approx. 3000 rpm by GV & ICV speed c**trol
Test Acceptance Criteria If maximum instantaneous speed is restricted below overspeed trip limits (111 %) ,therefore the load rejecti** test is regarded as successful.
C**firmati** items after Stabilizing -GVs are restored in no load positi** -turbine speed is c**trolled at near synchr**ous level -No abnormality is observed at electrical room and local positi**s.
Emergency Case If boiler trips by boiler protecti** , turbine shall be immediately tripped.
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الإهداءات
12-26-2010, 12:43 PM
Load Rejecti** Test (Governor Test)
المواضيع المتشابهه
فيديوهات يوتيوب الهندسية
قسم المحركات الكهربية و دوائر التحكم PLC ا
قسم خطوط النقل والتوزيع:: الكابلات الارضيةوالخط
قسم الانشاءات الكهربية
توليد الطاقه الكهربية والتحكم بها
العرض العادي
