Kalman filter

Example

Use in Lemonergy

Distinguish internal states from noisy measurement estimates.

This is a reference concept. No executable Lemonergy block has been verified for this term.

Connected concepts

Related concepts from the knowledge graph. Connections show context, not cause and effect. Hover or focus a linked term for its definition.

Battery management system

The electronics and software that keep a battery inside its safe window: measuring every cell voltage and many temperatures, estimating SOC and SOH, balancing cells, computing current limits, controlling the contactors and reporting over the vehicle network.

Coulomb counting

Estimating state of charge by integrating the measured current over time. Simple and fast, but sensor offset accumulates, so it is corrected against the OCV–SOC curve at rest or fused with it in a Kalman filter.

Data-driven SOC estimation

Estimating SOC with a model learned from data — LSTM neural networks, support vector regression, Gaussian processes — that maps histories of voltage, current and temperature to charge. It needs no physical model, but is only as good as its training data across temperature and aging, and is harder to verify for functional safety than a Kalman filter.

Equivalent circuit model

A cell model built from a voltage source for OCV, a series resistor and one or more RC pairs for the slower dynamics. Its few parameters are fitted from pulse tests, and it is what most battery management systems run in real time.

Fuzzy logic

Reasoning with degrees of truth between 0 and 1, so that a temperature can be partly ‘warm’ and partly ‘hot’, combined through if–then rules. It has been applied to SOC and SOH estimation and to charge control because it encodes expert knowledge without a precise model, though its rules and membership functions still need tuning on test data.

State of charge

How full a cell is, as a fraction of its available capacity. State of charge, like temperature, affects how fast a stored cell ages.

References & further reading

Technical references

1. Extended Kalman filtering for battery management systems of LiPB-based HEV battery packs: Part 3. State and parameter estimation

   Gregory L. Plett · Journal of Power Sources · 2004

   Technical reference · Model-based battery state-of-charge and parameter estimation with extended Kalman filtering, including uncertainty and model dependence.

Further reading on this topic

These sources provide broader context; they are not presented as citations for every statement in this entry.

2. Extended Kalman filtering for battery management systems of LiPB-based HEV battery packs: Part 2. Modeling and identification

   Gregory L. Plett · Journal of Power Sources · 2004

   Topic background · Battery charge balance, open-circuit voltage, ohmic loss, polarization dynamics and model identification; parameters require cell-specific data.