Synchronizer relay details – how it does the synchronization or making parallel connection of two circuit.

In parallel operation two different circuits are connected together called synchronized. A mismatch circuit if get synchronized, there will be flushing and other disaster incident.

The function of a synchronizer relay is to control the total synchronization procedure of alternators or different power circuits. We know that for synchronization the voltage, phase angle and frequency must be matched for two power circuits. Synchronizer relay watch over this parameters and when the condition fulfils, commands the close signal to circuit breaker to make to system synchronized.

How synchronizer relay works

An industrial synchronizer measures the busbar and generator voltages and frequencies and compares these, plus compares their phase angles. It controls the generator frequency and voltage, till they match the busbar values.

In order to determine phase accordance between the generator and the busbar, the synchronizer calculates a phase angle advance based on the circuit breaker closing time and the slip frequency.

When the phase difference is within this tolerance, the synchronizer transmits a closing signal for the generator circuit breaker ñ allowing time for this to close.

connection diagram of a synchronizer

Display of synchronization status in power plant