پاشکەوتنەوەی ژێنەراتۆر

Jieneratorê statîk nayê bi çubên dawiyê piştgirî bibe, di demê ku hêza electromotiv (EMF) li ser asta yekem yên din de sifir e, ev short circuitê pê bike. Prosedûyê synchronization û taybetmendiyên bikaranîn ê ji bo kontrolkirina we dike, heta yek alternator bi yek alternator din yê din yekan bibe an alternator bi busê bêhêman bibe.

Synchronization via Synchronising Lamps

Setî ya sê synchronizing lamps bikar bînin ji bo verifikasyonê şertên ji bo paralleling an synchronization machineyê nû bi yekê din. Yekana dark lamp method—ji bo synchronization bi veymetre—li jêr hatine ilustrandin. Ev yekana ji bo makinalên ku guçê nekîn uştê ye.

Synchronization Process Using Synchronizing Lamps

• Prime Mover and Voltage Adjustment

• Prime moverê ji machineyê nû dest pêbike û bi zelî derbas bikin tu heta lêzêna rating ê.

• Currentê fieldê ji machineyê nû tevahî bike heta voltageyê outputê wê bi voltageyê busê yek bibe.

• Frequency and Phase Detection

• Sê synchronizing lamps hatine flicker bikin bi reyê proporsional ê ji bo feraqê frequency ê di machineyê nû û bus de.

• Phase Sequence Check: Eger hemî lamps bi xwe rojname û dim bike, phase connections ê rast in. Eger na, phase sequence ê misaligned e.

• Corrective Actions and Switch Closure

• Ji bo rectifying phase sequence, her du line leads ê ji machineyê nû biyînin.

• Fine-tune frequency ê ji machineyê nû heta lamps flicker bikin bi reyê min ji yek dark period per second.

• Pas voltage adjustment ê final, switch ê synchronization bi ser midpoint ê dark period bicerbikin ji bo minimize voltage discrepancy.

Advantages of the Dark Lamp Method

• Cost-efficient compared to other synchronization techniques.

• Enables straightforward verification of correct phase sequence.

Disadvantages of the Dark Lamp Method

• Lamps appear dark at approximately 50% of their rated voltage, risking switch closure during residual phase differences.

• Frequent voltage fluctuations may cause filament burnout.

• Flicker behavior does not indicate whether the incoming frequency is higher or lower than the bus frequency.

Three Bright Lamp Method

• Connection Scheme: Lamps are cross-connected across phases (e.g., A1-B2, B1-C2, C1-A2).

• Synchronization Cue: If all lamps brighten and dim in unison, the phase sequence is correct.

• Optimal Switching: Close the switch at the peak of the bright period.

Two Bright One Dark Lamp Method

• Connection Configuration: One lamp is connected between corresponding phases (e.g., A1-A2), while the other two are cross-connected (e.g., B1-C2, C1-B2), as illustrated below.

• Phase Indication: The correct phase sequence is confirmed when one lamp remains dark while the other two alternate between brightness and darkness.

Connection Configuration and Synchronization Steps

In this setup, A1 is connected to A2, B1 to C2, and C1 to B2. The prime mover of the incoming machine is started and accelerated to its rated speed. The excitation of the incoming machine is adjusted such that the induced voltages EA1, EB2, EC3 match the busbar voltages VA1, VB1, VC1. The corresponding diagram is illustrated below.

Optimal Switch Closure and Phase Sequence Verification

The ideal moment to close the synchronizing switch occurs when the directly connected lamp (A1-A2) is fully dark while the cross-connected lamps (B1-C2, C1-B2) are equally bright. If the phase sequence is incorrect, this condition will not be met, and all lamps will either remain dark or flicker out of sync.

To correct the phase sequence, swap any two line connections of the incoming machine. Since the dark range of incandescent lamps spans a significant voltage interval (typically 40-60% of rated voltage), a voltmeter (V1) is connected across the directly connected lamp. The switch should be closed when the voltmeter reads zero, indicating minimal voltage difference between the incoming machine and the busbar.

Operational Modes and Automation

Once synchronized, the incoming machine "floats" on the busbar and can begin delivering power as a generator. If the prime mover is disengaged while connected, the machine will operate as a motor, drawing power from the grid.

• Small-Scale Synchronization: In low-power applications, three-lamp methods are often supplemented with a synchroscope to verify frequency matching.

• Large-Scale Automation: For high-capacity generators in power stations, computerized systems execute the entire synchronization process autonomously, ensuring precision and safety.