Project 1

Question:-1) Design a battery pack for a car roughly 150 Kw with 120 V. Use 3500 mAh 3.6V nominal NMC chemistry cell.

a. Design the battery pack configuration.

b. Draw the BMS topology for this battery pack.

Answer:-

Question:-2) Build a 3S2P battery pack configuration with generic battery block using Matlab/Simulink.

Answer:- 3S2P battery pack configuration-

block used- battery blocks, controlled current source, voltage measurement, bus selector, scope, display, constant, powergui

no. of series cell=3 , no. of parallel cell= 2

total no. of cell= no. of series cell * no. of parallel cell= 3*2 = 6

cell parameters are shown below

model:-

in this model 3 cells are in series (cell 1,2,3 & 4,5,6) , 2 cells are in parallel (cell 1,4 & 2,5 & 3,6) .

cell 1 mesurement port is connected to bus selector which will give signals ( SOC%, current & voltage) to scope,

voltage measurement block is connected across the battery pack, to show voltage in scope & in display.

controlled current source is given as load of battery pack, contant block is given for battery pack capacity.

in this simutation time is taken as 3600sec for 1 hr.

the above show the cell parameters,

so ,the nominal vol. of batt. pack= nominal cell vol. * no. of cell in series = 7.2 * 3 = 21.6 volts

rated capacity of batt. pack= nominal cell capacity * no. of cell in parallel = 5.4 * 2 = 10.8 Ah

the batt. pack is of 21.6 V 10.8Ah

the below fig. show the output of individual cell i.e. SOC%, current & voltage

plot 1 - SOC% of cell 1, starting the charge was 100% which reduce to 50% as per load.

plot 2 - show the current due to the load in the cell.

plot 3 - shows the voltage of cell at starting it has max. volt 8.3 which reduce to 7.667 volt.

the max. nominal volt of cell is 8.3, we can see in the cell block parameter

so, the max output voltage of batt. pack= max. nominal volt of cell * no. of cell in series

= 8.3*3 = 24.9 volt

teh above plot shows the output voltage of batt. pack is 24.49 volt after 1hrs.