Project 1

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. 

Cell specification: 

Nominal Voltage= 3.6V

Max. Voltage= 4.2V

Nominal cell capacity= 3500mAh = 3.5 Ah

Rated power=150kw

Rated voltage=120v

Battery Capacity          = Power/voltage 

                                       = 150000/120

                                       =1250Ah

No of Cells in series     =Total Battery voltage /cell voltage 

                                       =120/3.6

                                       =33.3s 

No of Cells in Parallel =TotalBattery Capacity /Cell capacity 

                                      =1250/3.5

                                      =357.1p

First finding the motor current= (rated power *1000)/rated voltage

                                                 = (150*1000)/120

                                                 =1250Ah

Round of value series 34S and parallel 358P

 b. Draw the BMS topology for this battery pack.

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

Total number of cells in battery pack  =no.of cells in series *no.of cells in parallel

                                                      =3*2

                                                      =6 calls 

Here, 

Cell Rated capacity     =3.5Ah

Nominal cell voltage   =3.6v

Maximum cell voltage = 4.2

Total number of cell in a battery pack  =6 cells 

Nominal voltage of the battery pack    =no of cells in series *no of cells in parallel

Nominal voltage of the battery pack    =3*3.6

                                                        =10.8v

Rated capacity of battery pack            = no of cells in parallel*rated capacity of a cell

                                                        =2*3.5

                                                        =7Ah

Overall voltage of the battery pack      =maximum capacity of the cell*no of cells in series 

                                                        =4.2*3

                                                        =12.6v

So the maxinum cell voltage is 4.2v*3s12.6v and we find simulation result is below display result 12.6v the ans is currect 

Series connection of a battery:

Battery are connected from terminal to terminal in a way that the +ve terminal one battery is connected to other battery -ve terminal and same battery +ve terminal is connected to other battery -ve terminal that is called series connection 

Parallel connection of a battery:

Batteries are connected from terminals to same terminals of the other batteries that is +ve terminal of one battery is connected to +ve terminal of other battery and -ve terminal of one battery is connected to -ve terminal of other battery

Simulation diagram for battery pack 3s2p 6 cells

 The output result is 12.57v displayed 

 

Simulation battery pack parameter is given: 

Soc,voltage,current result :

Output scope result below: