1. Summary
PW1005 is the BMS (Battery Management System) which is developed basing on the features of large-scale energy storage battery array. It is suitable for lead-acid battery. It performs stat monitor of battery array, protection and alarm. This document is for explaining the functions and technical parameters of BMS used in battery array of the energy storage power station. Matching battery array should be selected to the BMS.

1.1 Features of the system:
Intelligent management and protection for a longer battery life and run time
Modular design for extending easily, up to 360 Li-ion batteries in series
Accurate cell voltage monitor (± 1mV each cell), reliablely protecting against overcharge/ overdischarge
Full time active balance, max balance current is more than 5A, average balance current is more than 2A. Protects cells from disbalancing to maxmize battery capacity and battery life
Internal system uses CAN2.0 high-speed bus to transmit data efficiently
High accurace current monitor prevents battery from charging/discharging overcurrent
Each cell adopts SOC distribution estimation so that cell power can be controlled individually toprolong the battery life.
Multi-point temperature monitor

1.2 The main components of energy storage power statation including:
10V/380V isolation transformer: Performs the grid-connected operation of energay storage power station.
PCS (Power Converter System): PCS Converts alternating current (AC) to direct current (DC) and DC to AC.
Battery Array: The function of battery array is energay storage. Battery array needs monitoring and protection from BMS.
BMS is an important part of energy storage power station. BMS mainly performs following functions:
The triple protection function:
When reaching the first threshold value, requires monitor system to protect and informs PCS of going into the suspend state.
When reaching the second threshold value, startes relay contact protection.
When reaching the third threshold value, executes the internal system of BMS protection and cutting off the current loop.
Active balancing without heat dissipation
Estimate the state of charge (SOC) of battery array/battery cluster/battery pack
Records events
Display the state of battery pack
Manages authorization of BMS and setups parameters, including local setting and remote setting.

1.3 Primary components of the BMS:
BMU (Battery Management Unit):
BMU manages battery pack (A battery pack has 2 cells in parallel and 12 2-cell packs are wired in series is commonly referred to as a 12S, 2P (12 series, 2 parallel)).
BCMS (Battery Cluster Management System):
BCMS manages all the BMUs in a series curcuit, monitors the current in this curcuit, and takes protecting action when necessary.
BAMS (Battery Array Management System):
BAMS manages all the BCMs under the management of a PCS. BAMS communicates with PCS and background monitoring system, and requests PCS to adjust charging/discharging power based on the state of battery pack.