Battery Discharging Current Limit

Maximum battery discharging current

Since R2022b

• 

Libraries:
Simscape / Battery / BMS / Current Management

Description

This block calculates the maximum discharging current of a battery. Limiting the charging and discharging currents is an important consideration when you model battery packs.

This block supports single-precision and double-precision floating-point simulation.

Note

To enable single-precision floating-point simulation, the data type of all inputs and parameters must be single.

This diagram shows the structure of the block:

Equations

The discharging current limit is equal to the minimum of these values:

• The temperature-dependent limit for the coolest and hottest cells

• The theoretical current based on the undervoltage limit of the cell

• The terminal resistance

$$\begin{array}{l}CurrentLimit=-\min \left(i_1,i_2,i_3\right)\\ i_1=\frac{\min (CellVoltage)-UndervoltageLimit}{R_0}\\ i_2=f(min(CellTemperature))\\ i_3=g(max(CellTemperature))\end{array}$$

where

• UndervoltageLimit is the value of the Cell undervoltage limit (V) parameter.

• CellVoltage is the value of the CellVoltage input port.

• R₀ is the value of the Terminal resistance (ohm) parameter.

• CellTemperature is the value of the CellTemperature input port.

Ports

Input

CellVoltage — Cell voltages

scalar | vector

Cell voltage, in volt, specified as a scalar for a single cell or a vector for multiple cells.

CellTemperature — Cell temperatures

scalar | vector

Temperature of the cells, specified as a scalar for a single cell or a vector for multiple cells. The size of this input port must be equal to the size of the CellVoltage parameter.

Output

CurrentLimit — Discharging current limit

scalar

Discharging current limit for the battery pack, returned as a scalar.

Parameters

Cell undervoltage limit (V) — Undervoltage limit for cell

2.5 (default) | positive scalar

Limit under which the battery cell is undercharged, in volt.

Terminal resistance (ohm) — Terminal resistance

0.0025 (default) | positive scalar

Terminal resistance, R₀, in ohm.

Vector of temperatures, T — Cell temperatures

[243.15, 258.15, 273.15, 288.15, 303.15, 318.15, 333.15] (default) | vector of scalars

Cell temperatures. The physical unit of this parameter must be the same as the physical unit of the CellTemperature input port.

Current limit for coolest cell, iCool(T), (A) — Current limit for coolest cell

[ 0, 0, 0, 0, 100, 100, 100] (default) | vector of positive scalars

Current limit for the coolest cell, in ampere. The size of this vector must be equal to the size of the Vector of temperature, T parameter.

Current limit for hottest cell, iHot(T), (A) — Current limit for hottest cell

[100, 100, 100, 100, 0, 0, 0] (default) | vector of positive scalars

Current limit for the hottest cell, in ampere. The size of this vector must be equal to the size of the Vector of temperature, T parameter.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.

Version History

Introduced in R2022b