Kasuwanci Ingantaccen Gidajen Karkashin Kirkiro

Takaitaccen Excitation

Yadda ya faru cikin takaitaccen excitation a generator yana faru idan tushen excitation ta kasance, wanda yake sa generator a tunna masu gaba da sama na synchroni.

Na'urar Generator Induction

Babu excitation, generator ya zama generator induction, wanda zai iya haifar da kuma karshen abubuwa.

Gagarbin Undercurrent Relay

Undercurrent relay zai iya gagar da takaitaccen field daga baya idan current na excitation ya koma zuwa adadin batu.

Relay na zai yi aiki idan current na excitation ya koma zuwa adadin batu, kamar 8% na rated full load current. Idan circuit na field yana cika amma exciter ta kasance, induced current a slip frequency zai iya haifar da relay suka yi aiki da kuma suka rufe. Wannan zai iya gudanar da tsari ga settings na relay.

Setting na 5% na normal full load current ita ce mafi kyau. Undercurrent relay na contact na normally closed wanda yake zama open inda coil na relay ta shiga kan current na excitation. Idan system na excitation ta kasance, coil na relay ta fito, ana ci contact na biyu da kuma suka bayar da power zuwa timing relay T1.

Idan coil na relay ta shiga, contact na normally open na relay T1 ta ci. Contact na biyu ta ci supply across timing relay T2 da adjustable pickup time delay na 2 zuwa 10 seconds. Relay T1 ta time delayed on drop off don stabilize scheme again slip frequency effect. Relay T2 ta ci contacts na biyu ba da prescribed time delay don either shut down the set ko initiate an alarm. Ita time delayed on pickup don prevent spurious operation of the scheme during an external fault.

Timing Relays for Stability

Amfani da timing relays ya taimaka stabiliyanci protection scheme against slip frequency effects and prevent false operations.

A sani cewa voltage na system ce main indication of system stability. Saboda haka offset mho relay ya kiranta machine down instantaneously when operation of generator is accompanied by a system voltage collapse. Drop in system voltage ta samun under voltage relay da take set to approximately 70 % of normal rated system voltage. Offset mho relay ya kiranta initiate load shedding to the system up to a safe value and then to initiate a master tripping relay after a predetermined time.

Advanced Protection for Large Generators

For larger generators, advanced schemes with offset mho relays and under voltage relays are used to maintain system stability through load shedding and master tripping relays.