HV Control Insfrastructure : Bay Controllers and Protection Relays

[Ashdgee]

Hi all,

I have done mainly substation design up to medium voltage level (44kV). I am starting to get into HV Design as well and I am going through a case study.

My question is about Bay Control Units (BCUs).I see bay control units have digital inputs and outputs just like protection relays.Does it mean it replaces your normal protection relays in a high voltage switch yard ? How do BCU's relate with the normal protection relays ? What is the main difference between the two?

 

[RRaghunath]

Bay control units (BCUs) are (as the name suggests) used for switchgear control basically.
These can include protection functions but not preferred, except the BF protection.
All the relays communicate to Substation Control System (SCS) and to SCADA through BCUs.

 

[Ashdgee]

Many thanks