Prînsîpê çalakirinê serbest (CS) di rûbaran de

Rêbaza Controlled Switching (CS)

Controlled Switching (CS) yek taybetmendî ye ku bi serperestkirina dawiyên daqiqan de dest pê kirin da çavkaniya circuit breakers (CBs) bikin. Firotina ya barkerdibûn an vekirina CB ji bo serperestkirina tişteyên transîyant hatine birdayî kirin.

Prinsîpên Serke:

• Zero Crossing ya Voltage ji bo Vekirina: Ji bo serperestkirina tişteyên transîyant, dema vekirina çavkanê divê li ser zero crossing point be. Ev diha niha current di dema ku voltage li ser minimum be de dest pê dike, ji bo serperestkirina inrush currents û tiştekên wekî.

• Bypassing Protection Commands: Ji bo vekirina kontrolkirin, herêmî ye ku hemî firotinan ya protection trip, paşîn wê ku li ser fault interruptions ve hatine trigger kirin, controlled switching controller bypass bikin. Ev diha niha system bi çêrçava bi seda xwe re bidest kiriye bike.

• Mînak Scenario: Energizing a Capacitor Bank

• Input Command: Ji bo energizing capacitor bank, input command bi ser controlled switching controller hatine şandin.

• Reference Time Instant: Controller reference time instant diha niha li ser phase angle ya busbar voltage taybetmendî kirin.

• Waiting Time Calculation: Ji bo hesabkirina waiting time, controller closing command ji bo CB şandin.

• Closing Command Timing: Timing exact closing command li ser make time predictable ya CB û target point for making (typically the voltage zero crossing) taybetmendî kirin.

• Ev parametreyan pre-programmed into the controller ne.

• Minimizing Transients: CB then closes at the correct time instant, thereby minimizing switching transients.

Time Sequence in Controlled Switching

The following steps outline the sequence of events in controlled switching for a single phase of a circuit breaker:

• Initial Command: An input command is received to either close or open the CB.

• Phase Angle Detection: The controller detects the phase angle of the busbar voltage.

• Waiting Period: The controller calculates and waits for the appropriate internal delay.

• Closing Command Issued: Once the calculated waiting period elapses, the controller sends a closing command to the CB.

• Contact Closure: The CB makes contact at the predetermined optimal time (voltage zero crossing), minimizing transients.

Visual Representation

A diagram would typically show the time sequence involved in controlled switching, highlighting the relationship between the busbar voltage waveform, the internal waiting time, and the precise moment of contact closure.