Substation DC system
The main function of substation DC system is to ensure uninterrupted power supply for essential loads.
ensure uninterrupted power supply for essential loads
Problems and solutions
LAB have a “memory effect”, which means that the battery must be completely discharged before charging
Long charging time. On average, a full charge takes 8 to 10 hours
Discharge depth without the service life reduction is less than 60% of the rated capacity
Low power characteristics. On average, LAB can produce a continuous current of about 0,5 C. That means, that LAB with capacity of 100 A * h would provide the maximum continuous current of 50 A.
The discharge curve of LAB is flat, and the battery voltage seriously depends on the charge level.
Low charge efficiency of lead-acid batteries - 65-85%
High self-discharge rate (up to 15% per month)
Providing and reserving power for in-house needs and power facilities. Instant switch to battery power when the mains voltage disappears.
LIB are capable of charging at any charge level keeping the ability to return the full capacity
Significantly shorter charging time. The standard charge mode is 1 hour, which significantly reduces the time of operational readiness after a full discharge.
LIB allows up to 80% depth of discharge. Thus, with the same rated capacity, LIB can produce more power
High power characteristics. LIB in normal mode can produce a current of 3 C. Thus, LIB with a capacity of 100 A * h would provide the maximum continuous current of 300 A. This advantage allows to significantly reduce the nominal capacity of LIB compared to LAB. Thus, when replacing the battery in a substation DC system, the initial cost of the power accumulating device on LIB is equal to the cost of a device on scab LAB, or even less.
The discharge curve of LIB in the range from 100% to 20% of the charge is almost horizontal straight line, the battery voltage is nearly constant in that range
High charge efficiency of LIB - 93-95%
Low self-discharge rate (on average, 3% per month)
A charging room is required - a hazardous production facility
Inefficient monitoring of battery condition during operation
No charging room required (decommission of a hazardous production facility is possible)
A built-in monitoring system (BMS) that monitors the status of each element's parameters and can transmit results). In case of emergency or critical situations, BMS sends a signal to the switch gear and disconnects the energy storage device from the load and network.
Low energy density in LAB ⇒ high mass and large dimensions ⇒ need for work areas
LAB require maintenance at a certain interval during operation (for example, monitoring the appearance, leveling the electrolyte level), which entails the need for maintenance personnel
Accelerated LAB degradation ⇒ frequent battery replacement
Occupied area is reduced, no need for a room with exhaust ventilation. Thus, the battery may be placed almost at any room of a substation.
LIB are sealed and do not require maintenance.
LIB does not need to be replaced during the entire service life
Composition of OOPT
- Rectifier charger
- Battery switchgear cabinet
- Battery and control cabinet
- DC board
- Operating current distribution cabinet
|Operating temperature, С|
|Maximum discharge current|
|Peak discharge current (5 sec)|
|Service life (DOD80%), cycles|
|Module power, kW|
|Fire extinguishing system|
|Maximum battery voltage|
We are ready to develop a custom-tailored solution for each client and offer a flexible list of specifications for your project. You can choose the dimensions, charging and running time, and other specifications.
We also offer cooperation throughout the entire project life cycle — from energy audit to technical support, as well as beneficial financial cooperation.
and we'll get back to you as soon as possible.