Passive Interface

Passive interface between battery and cell supervisory circuit

Since R2022b

• 

Libraries:
Simscape / Battery / HIL

Description

The Passive Interface block provides an abstracted passive interface between a battery and a cell supervisory circuit. Use this block with desktop simulations and hardware-in-the-loop battery emulation hardware.

A cell supervisory circuit is an electronic circuit that connects to battery cells or parallel assemblies. You can use this circuit to normalize voltages or states-of-charge (SOC) inside a module or pack. In the real world, you implement this equipment between your battery and the battery management system (BMS) control.

In this figure, the items in blue represent real-world equipment, voltages, and currents.

To avoid damaging your battery and to test your cell balancing algorithms under standard operational conditions and fault conditions, you can use hardware-in-the-loop battery emulation hardware. An abstracted interface facilitates connecting, setting, and configuring the passive balancing BMS to your emulated battery.

In this figure:

• The blue color represents real-world equipment, voltages, and currents.

• The green color represents the interface between the real-world equipment, voltages, and currents, as well as the simulated equipment, voltages, and currents.

• The orange color represents the simulated equipment, voltages, and currents.

The Passive Interface block provides the abstract representation of power electronic equipment without the need to model it in detail. For example, if you have a battery pack with different levels of temperature or voltage within its constituent parts, you can use this block to check if the BMS is correctly balancing your pack after a variety of operational scenarios.

SOC Optional Ports

Use the optional SOC ports of the Passive Interface block to avoid implementing an SOC estimation algorithm in the BMS, to validate and verify the SOC estimation algorithm against the simulated SOC, or to represent a real-world battery.

• If, in your model, the battery has an SOC output port, expose the SOC input port of this block and connect the ports appropriately. To expose the SOC input port of this block, set the Expose SOC input port parameter to Yes.

• To avoid implementing an SOC estimation algorithm in the BMS or to validate and verify the SOC estimation algorithm against the simulated SOC, expose the SOC output port of this block and connect it to your BMS. To expose the SOC output port of this block, set the Expose SOC output port parameter to Yes.

• To represent a real-world battery, do not expose the SOC ports of this block.

Thermal and Temperature Optional Ports

Use the optional thermal and temperature ports of the Passive Interface block to represent a battery with a temperature sensor or to validate and verify the temperature estimation algorithm against the simulated temperature.

• If, in your model, the battery has a temperature sensor, expose the thermal port H of this block and connect it to the thermal network. To expose the thermal port of this block, set the Thermal port parameter to Model.

• To validate and verify the temperature estimation algorithm against the simulated temperature, expose the thermal port H and the temperature measurement port T of this block and connect them to the thermal network and your BMS, respectively. To expose the temperature measurement port of this block, set the Expose temperature measurement port parameter to Yes.

• If, in your model, the battery does not include thermal effects or does not have a temperature sensor, do not expose the thermal and temperature ports of this block.

Ports

Input

Icsc_discharge — Discharge current from cell supervisory circuit, A

physical signal | scalar

Discharge current from the cell supervisory circuit, in ampere.

SOC — Battery state-of-charge, unitless

physical signal | scalar

State-of-charge of the battery, in percent.

Dependencies

To enable this port, set the Expose SOC input port parameter to Yes.

Output

Vbat — Battery voltage, V

physical signal

Voltage across the battery, in volt.

Icsc — Cell supervisory circuit current, A

physical signal

Current flowing through the cell supervisory circuit, in ampere.

The value at this port is always numerically identical to the value at the Icsc_discharge port. This port simply provides consistency with the Active Interface block or with any hardware that requires it.

Dependencies

To enable this port, set the Expose cell supervisory circuit current measurement port parameter to Yes.

SOC — Battery state-of-charge, unitless

physical signal

State-of-charge of the battery, in percent.

Dependencies

To enable this port, set the Expose SOC output port parameter to Yes.

T — Temperature measurement, K

physical signal

Temperature of the battery, in kelvin.

Dependencies

To enable this port, set the Expose temperature measurement port parameter to Yes.

Conserving

+ — Positive terminal

electrical

Electrical conserving port associated with the positive terminal of the interface.

- — Negative terminal

electrical

Electrical conserving port associated with the negative terminal of the interface.

H — Thermal port

thermal

Thermal conserving port.

Dependencies

To enable this port, set the Thermal port parameter to Model.

Parameters

Expose cell supervisory circuit current measurement port — Measurement port visibility for cell supervisory circuit current

Yes (default) | No

Option to expose the port that measures the current from the cell supervisory circuit.

Expose SOC input port — SOC input port visibility

No (default) | Yes

Option to expose the battery SOC input port.

Expose SOC output port — SOC output port visibility

Yes (default) | No

Option to expose the battery SOC output port.

Dependencies

To enable this parameter, set Expose SOC input port to Yes.

Thermal port — Thermal port visibility

Omit (default) | Model

Option to model the thermal port of the passive interface.

Expose temperature measurement port — Temperature measurement port visibility

Yes (default) | No

Option to expose the port that measures the temperature of the battery.

Dependencies

To enable this parameter, set Thermal port to Model.

Extended Capabilities

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

Version History

Introduced in R2022b