Week 7 State of charge estimation

harness dashboard

test 1

all clear

test 2

3rd test

The plot with Cell Voltages shows the voltages of all 6 cells connected in series. The cell voltage keeps on dropping as the battery keeps on discharging up to 0 states of charge and the simulation is paused. The plot with Pack Current represents the current drawn and given to the battery while charging/ discharging. Here thebattery repeats charging and discharging pattern as explained above in the charging and discharging load.The plots the cell temperature of all all cells can see then while charging and discharging the cell temperature increases.The plot shows the input state as per the given input, the simulation only runs in discharging mode and the SOC reaches zero the simulation is stopped.The plot shows the state of charge of the entire pack by 3 different methods. The soc curve decreases at discharge and increases while charging. Here the battery keeps on discharging as the regenerative charging is very less.The plot shows the cell balancing command for all cells.

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Conclusion:

Coulomb counting is a technique used to track Charge of a battery pack. It works by integrating the active flowing current over time the total sum of energy entering/ leaving the battery pack. As we observe the SOC of the cells were different this is due to the different calculation which is done in SOC simulation and balancing block. SOC estimations work in 3 different formats. The1st block represents the coulomb counting block and the 2nd block represents UKF and EKF block. .The coulomb counting is the integration of the current over the period of time in the discrete-time integrator, current is been integrated by taking temperature into consideration.Discrete-time integrator blocks work in Z-domain. Temperature values taken by the lookup table form. the SOC is by Discrete-time integrator block.