Parameter Identification and State of Charge Estimation of NMC Cells Based on Improved Ant Lion Optimizer

Table 1

SOC estimation procedure based on SVD-UKF.

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Step I: Initialization: At k=0, assign , , ,

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Step II: Time update: For ,

Calculate sigma points: ,

 ;

 ,

Calculate new sigma points:

Update the state mean:

Update the state error covariance matrix:

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Step III: Measurement update:

Obtain the output sigma points:

Calculate the measurement mean:

Calculate the measurement error covariance matrix:

Calculate the state and measurement error covariance matrix:

Calculate Kalman gain:

Measurement update of state estimate:

Measurement update of error covariance:

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Step IV: SOC estimation result:

  and turn to Step 2 for next iteration estimation

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