Substation Battery Charger: A Complete Guide on Battery Chargers used in transmission substations

What is a Substation Battery Charger ?

Answer:
A Battery Charger is an important element of auxiliary power systems (APS) , which supplies DC Supply to the Substation DC Loads and at the same time continuously charges the Substation Battery Set.

What are the different modes in which the Battery Charger Operates ?

Answer:
There are two modes: Boost Mode and Trickle or Float Mode
1) Trickle or Float Mode:This is Constant Voltage Mode, by which it supplies Trickle-Charging Current to Battery as well as Station Load.
i) Even though there is no load on the Battery, there is a Local Discharge which drains the Battery. In this mode, BC Floats the Batteries at 2.25 V Per Cell with a Stabilization of + 1% of the Floating Voltage, so as to keep the Battery in fully Charged condition all the time and compensate for the local discharge.
ii) Supplies Constant Voltage to the Substation DC Load.
2) Boost Mode:
It can be used in CC or CV Modes.
It is used for charging the Battery in quick time, after a full or a partial Battery Discharge.