Dutsen Kirkiro Turbin

Kirkiya yana da tashin kirkiyar gida na tsawon alama, tashin ido da ke dacewa a wurare masu kirkiya, da kuma tafakun hawa. Wadannan su ne suna da muhimmanci wajen inganta da tsohon kirkiya ko alternator. Hata ba a yi amfani da shi daidai, amma a cikin halayin da ya fi yawa, ba a yi zama a yi da shi tushen da aka bayarwa a kan shekaru dubu, amma a yi zama a yi da shi hasken da aka fara a kan abubuwan da suka fada.

Yana da kyau a yi amfani da adadin da za a iya da shi don in inganta da abubuwan da suka fada da kuma halayin da suka fitowa masu kirkiya don in iya ci gaba a kan shi da dalilin da na da kyau. Hata ba a yi amfani da hanyoyin da za a iya da shi don in bincika da tushen da aka bayarwa, da kuma hanyoyin da za a iya da shi don in inganta da shi - ba za a iya kara mafi nasarar da aka bayarwa daga kirkiya ba. Muhimman abubuwan da ake amfani a kan tsohon kirkiya, suna da kyau a yi amfani da shi don in iya kara mafi nasarar da aka bayarwa a kan shi lokacin da yake samu mafi nasarar da aka bayarwa.

Kirkiya mai sauƙi da yawa yana iya samu mafi nasarar da aka bayarwa a kan gida ko a kan gwamnati ko kuma a kan biyu. Masu kirkiya suna daɗi ake sanya a gwamnatin sauran ta'adanci, saboda haka waɗanda ake samu mafi nasarar da aka bayarwa a kan gwamnati yana da kyau a kara mafi nasarar da aka bayarwa daga kirkiya a matsayin lokaci, mara yana iya kara mafi nasarar da aka bayarwa a kan kirkiya.

Adadin da kuma abubuwan da suka samu mafi nasarar da aka bayarwa a kan kirkiya su ne da damu. Saboda haka, masu kirkiya ko alternator suna da kyau a yi amfani da hukumomin da suka samu mafi nasarar da aka bayarwa. Tsohon kirkiya yana da hukumomin da suka samu mafi nasarar da aka bayarwa da kuma hukumomin da ba suka samu mafi nasarar da aka bayarwa ba. Yana da kyau a yi amfani da hanyoyin da za a iya da shi don in bincika da hukumomin da suka samu mafi nasarar da aka bayarwa da kuma hukumomin da za a iya da shi don in iya ci gaba a kan tsohon kirkiya da na da kyau.

Abubuwan da Ake Amfani Don In Inganta Da Kirkiya

Hukumomin da ake amfani don in inganta da kirkiya su ne da damu, su ne:

1. Relays da ake amfani don in tabbatar da mafi nasarar da aka bayarwa a kan gwamnati.

2. Relays da ake amfani don in tabbatar da mafi nasarar da aka bayarwa a kan kirkiya.

Daga relays, wadannan da ake amfani da shi daidai don in inganta da kirkiya da kuma transformer da ake sanya shi, akwai lightning arrestors, hukumomin da ake amfani don in inganta da tashin ido da ke dacewa, hukumomin da ake amfani don in inganta da tashin ido, hukumomin da ake amfani don in inganta da tashin ido da stator winding, transformer winding da kuma transformer oil. Daga cikin wadannan hukumomin, akwai mafi girma da su ba su karɓa ba, amma suke a yi amfani don in tabbatar da wasu abubuwa lokacin da abubuwan da suka fada.

Amma wasu hukumomin da suke a yi amfani suke a yi amfani don in karɓa relay da ake amfani don in karɓa kirkiya. Yana da kyau a jin da ba a yi amfani da relay da za a iya inganta da mafi nasarar da aka bayarwa, amma a yi amfani da shi don in tabbatar da mafi nasarar da aka bayarwa da kuma in kara mafi nasarar da aka bayarwa daga kirkiya lokacin da yake samu mafi nasarar da aka bayarwa, mara yana iya kara mafi nasarar da aka bayarwa a kan shi.

Yana da kyau a iya kara mafi nasarar da aka bayarwa a kan kirkiya, saboda haka, yana da kyau a yi amfani da capacitor ko surge diverter ko biyu don in kara mafi nasarar da aka bayarwa a kan kirkiya. Hukumomin da ake amfani don in inganta da kirkiya su ne da damu, zan iya bayyana a nan a kan gabas.

Ingantaccen Kirkiya Da Ba A Yi Amfani Da Alama Ba

Tsohon ingantaccen da ake amfani a kan stator winding don in inganta da mafi nasarar da aka bayarwa a kan phase to phase ko phase to earth fault, yana da longitudinal differential protection of generator. Abin da ake amfani a kan stator winding yana da inter turn fault protection.

Wannan hukumomin ba a yi amfani a baya, saboda idan an samu mafi nasarar da aka bayarwa a kan points a kan phase winding, wanda ake cika a kan slot, da kuma wanda ake da potential difference, yana da kyau a yi amfani a kan stator differential protection ko stator earth fault protection.

Kirkiya yana da kyau a yi amfani da harsuna da mutane da ake amfani a kan slots. Idan an yi kirkiya da tashin harsuna da mutane, wannan hukumomin yana da kyau a yi amfani don in inganta da kirkiya.

Stator Earth Fault Protection

Idan stator neutral yana da kyau a yi amfani da resistor, ake amfani current transformer a kan neutral to earth connection. Inverse time relay ake amfani a kan CT secondary idan kirkiya yana da kyau a yi amfani a kan bus bar. Idan kirkiya yana da kyau a yi amfani a kan delta star transformer, ake amfani instantaneous relay a kan sama.

A cikin hali na farko, yana da kyau a yi amfani a kan inverse time relay saboda hukumomin da za a iya da shi don in inganta da abubuwan da suka fada a kan system. Amma a cikin hali na biyu, earth fault loop yana da kyau a yi amfani a kan stator winding da primary winding of the transformer, saboda haka, ba a yi amfani a kan grading ko discrimination a kan system. Saboda haka, Instantaneous Relay yana da kyau a yi amfani a kan hali na biyu.

Rotor Earth Fault Protection

Mafi nasarar da aka bayarwa a kan rotor ba a yi abin da ya fi yawa ba, amma idan an samu mafi nasarar da aka bayarwa a kan biyu, field winding yana da kyau a yi amfani a kan short-circuit da kuma magnetic field yana da kyau a yi amfani a kan system, saboda haka, yana da kyau a yi amfani a kan mechanical damage a kan bearings of the generator. Akwai mafi girma hukumomin da ake amfani don in tabbatar da wannan mafi nasarar da aka bayarwa a kan rotor. Wadannan hukumomin su ne:

1. Potentiometer method

2. AC injection method

3. DC injection method

Unbalanced Stator Loading Protection

Unbalancing a kan loading yana da kyau a yi amfani a kan negative sequence currents a kan stator circuit. Wannan negative sequence current yana da kyau a yi amfani a kan reaction field rotating at twice of synchronous speed with respect to the rotor and hence induce double frequency current in the rotor. Wannan current yana da kyau a yi amfani a kan overheat a kan rotor circuit, especially in the alternator.

Idan unbalancing yana da kyau a yi amfani a kan fault a kan stator winding itself, wannan yana da kyau a yi amfani a kan differential protection provided in the generator. Idan unbalancing yana da kyau a yi amfani a kan fault a kan gwamnati ko unbalanced loading a kan system, yana da kyau a yi amfani a kan negative phase sequence relay with the characteristics to match the withstand curve of the machine.

Ingantaccen Kirkiya Da Ba A Yi Amfani Da Overheating Ba

Overloading yana da kyau a yi amfani a kan overheating a kan stator winding of the generator. Ba overloading ba, failure of cooling systems and insulation failure of stator laminations yana da kyau a yi amfani a kan overheating of the stator winding.

Overheating yana da kyau a yi amfani a kan embedded temperature detectors at various points in the stator winding. The temperature detector coils are normally resistance elements which form one arm of the wheatstone bridge circuit. In the case of smaller generator normally below 30 MW, the generators are not equipped with embedded temperature coil but are usually fitted with thermal relay and they are arranged to measure the current flowing in the stator winding.

This arrangement only detects overheating caused by overloading and does not provide any protection against overheating due to failure of cooling systems or short circuited stator laminations. Although over current relays, negative phase sequence relays, and devises for monitoring constant flow are also used to provide a certain degree of thermal overload protection.

Low Vacuum Protection

This protection, usually is in the form of a regulator which compares the vacuum against atmospheric pressure, it is normally fitted to the generator set above 30 MW. The modern practice is for the regulator to unload the set via the secondary governor until normal vacuum conditions are restored. If the vacuum conditions do not improve below 21 inch the stop valves are closed and the main circuit breaker is tripped.

Ingantaccen Kirkiya Da Ba A Yi Amfani Da Lubrication Oil Failure Ba

This protection is not considered essential since the lubrication oil is normally obtained from the same pump as governor oil and a failure of the governor oil will automatically make stop valve to close.

Ingantaccen Kirkiya Da Ba A Yi Amfani Da Loss of Boiler Firing Ba

Two methods are available for detecting the loss of boiler firing. In the first method, normally opened (NO) contacts are provided with the fan motors which may trip the generator if more than two motors fail. The second methods use a boiler pressure contacts which unload the generator if boiler pressure falls below approximately 90%.

Ingantaccen Kirkiya Da Ba A Yi Amfani Da Prime Mover Failure Ba

If the prime mover fails to supply mechanical energy to the generator, the generator will continue to rotate in motoring mode that means it takes electrical energy from the system instead of supplying it to the system.

In a steam turbine the steam acts as a coolant maintaining the turbine