2 replies to this topic

[deep]

Hi ,
I am using Thyristors for capacitor switching and have a question
Which switching is better for both capacitor and thyristor? All three phases or two phases only.
What is benefit and loss between them.

Regards,
Deep

[PowerQualityDoctor]

Hi ,
I am using Thyristors for capacitor switching and have a question
Which switching is better for both capacitor and thyristor? All three phases or two phases only.
What is benefit and loss between them.

Regards,
Deep

In short:
2 switches - less initial cost, less losses, capacitors always has voltage (longer discharge time after shutdown).
3 swtiches - allows unbalanced control (if the load is not equal on all phases)

To summarize, if the load is balanced, 2 switches is better.

[marke]

Two switches is technically easier and lower cost.
The major disadvantage is that one phase is always connected to the capacitors which can be a problem if there is leakage to ground.
Two phase control also has lower power dissipation.

Best regards,