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Chapter 2 Introduction to energy storage system
2.1 System application
As shown in Fig. 2-1, the energy storage system set up by PWS2-30M-EX is composed of
battery (pack), energy storage inverter, intelligent (or manual) power distribution unit, EMS
and BMS. Battery pack is connected to energy storage inverter. Energy storage inverter is
connected with the load and power grid through intelligent (or manual) power distribution
unit. Energy storage inverter communicates with EMS through Ethernet interface (or RS-
485 interface) to indirectly control charging and discharging of battery pack. EMS
communicates with energy storage inverter, BMS and/or intelligent electric meter through
RS-485 interface to dispatch the energy of an energy storage system.
2.1.1 System structure diagram
The structure diagram of energy storage system is shown below. PWS2-30M-EX energy
storage inverter pushes the data to EMS or other host systems in real time.
The Intelligent power distribution unite is a remote controllable disconnector. A manual
switch can also work. This component is used to isolate the grid when the system needs
to run in off-grid mode.
Energy Management
System
Intelligent Power
Distribution Unit
or manual switch
Grid
Ethernet/RS-485
Energy Storage Inverter
Battery and
Industrial Load
Battery Management
System
RS-485
Communication
Fig. 2-1 Structure of energy storage system
