Power Accounting Bus Creator

Create power information bus

Libraries:
Powertrain Blockset / Utilities / Power Accounting

Description

Creates a power information bus for reporting system power and energy consumption. You can associate the block to a parent system, select types of power signals to track, and add signal descriptions. If you want to generate a power and energy report, you must use this block to log the power signals in your plant model blocks. The Powertrain Blockset™ plant blocks use the Power Accounting Bus Creator to log the power signals. The documentation for each block includes information about the logged power bus signals.

The system-level power and energy accounting satisfies the conservation of energy.

$\sum^{} P_{t r a n s} + \sum^{} P_{n o t t r a n s} = \sum^{} P_{s t o r e}$

To add the Power Accounting Bus Creator to your plant block, follow these steps:

Add the Power Accounting Bus Creator block to your block.
Select the types of power signals that you want to log. See Power Signals.
Associate the Power Accounting Bus Creator with a parent subsystem. See Block Association.
Connect the power signals to the Power Accounting Bus Creator.
- Follow the sign convention.
- To ensure that your plant block conserves energy, include all power associated with the block.
In the Power Accounting Bus Creator:
- On the Transferred power tab, specify these parameters:
  - Associated Port
  - Description
- On the Not Transferred power tab, specify the Description parameter:
In the plant block, connect the transferred power signals to the Power Accounting Bus Creator ports that are specified with the Associated Port parameter.

Power Signals

The Power Accounting Bus Creator sorts the signals into three power types.

Power Type	Description	Examples
P_trans	Transferred	Power transferred between blocks: Positive signals indicate flow into block Negative signals indicate flow out of block	Crankshaft power transferred from mapped engine to transmission. Road load power transferred from wheel to vehicle. Rate of heat flow transferred from throttle to manifold volume.
P_nottrans	Not transferred	Power crossing the block boundary, but not transferred: Positive signals indicate an input Negative signals indicate a loss	Rate of heat transfer with the environment. From environment is an input (positive signal) To environment is a loss (negative signal) Flow boundary with the environment. From environment is an input (positive signal) To environment is a loss (negative signal) Mapped engine fuel flow.
P_store	Stored	Stored energy rate of change: Positive signals indicate an increase Negative signals indicate a decrease	Energy rate of change: Battery storage Kinetic energy in drivetrain components Vehicle potential energy Vehicle velocity

Power Type

Description

Examples

P_trans

Transferred

Power transferred between blocks:

Positive signals indicate flow into block
Negative signals indicate flow out of block

Crankshaft power transferred from mapped engine to transmission.
Road load power transferred from wheel to vehicle.
Rate of heat flow transferred from throttle to manifold volume.

P_nottrans

Not transferred

Power crossing the block boundary, but not transferred:

Positive signals indicate an input
Negative signals indicate a loss

Rate of heat transfer with the environment.
- From environment is an input (positive signal)
- To environment is a loss (negative signal)
Flow boundary with the environment.
- From environment is an input (positive signal)
- To environment is a loss (negative signal)
Mapped engine fuel flow.

P_store

Stored

Stored energy rate of change:

Positive signals indicate an increase
Negative signals indicate a decrease

Energy rate of change:

Battery storage
Kinetic energy in drivetrain components
Vehicle potential energy
Vehicle velocity

Block Association

When you add the Power Accounting Bus Creator to your plant block, you associate the signals to a parent block. There are two association methods.

Method Description Example

Method	Description	Example
`Parent`	Power Accounting Bus Creator associates the power bus signals with the parent block.	In the conventional vehicle reference application, navigate to the `Passenger Car > Engine > SiMappedEngine > Accessory Load Model` plant subsystem. Open the Power Accounting Bus Creator. The Associated block parameter is set to `Parent`, so the Power Accounting Bus Creator associates the power signals with the `Accessory Load Model` plant subsystem.
`Parent reference block`	Power Accounting Bus Creator associates the power bus signals with a reference block. Use the Library block name parameter to specify the block.	In the Ideal Fixed Gear Transmission block, navigate to the `Bus Creation` subsystem. Open the Power Accounting Bus Creator. The Power Accounting Bus Creator block uses these parameter settings to associate the power signals to the Ideal Fixed Gear Transmission block. Associated block parameter is set to `Parent reference block`. Library block name parameter is set to `'autolibsharedtransfixedgear/Ideal Fixed Gear Transmission'`.

Parent

Power Accounting Bus Creator associates the power bus signals with the parent block.

In the conventional vehicle reference application, navigate to the Passenger Car > Engine > SiMappedEngine > Accessory Load Model plant subsystem. Open the Power Accounting Bus Creator.

The Associated block parameter is set to Parent, so the Power Accounting Bus Creator associates the power signals with the Accessory Load Model plant subsystem.

Parent reference block

Power Accounting Bus Creator associates the power bus signals with a reference block.

Use the Library block name parameter to specify the block.

In the Ideal Fixed Gear Transmission block, navigate to the Bus Creation subsystem. Open the Power Accounting Bus Creator.

The Power Accounting Bus Creator block uses these parameter settings to associate the power signals to the Ideal Fixed Gear Transmission block.

Associated block parameter is set to Parent reference block.
Library block name parameter is set to 'autolibsharedtransfixedgear/Ideal Fixed Gear Transmission'.

Ports

Input

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PwrTrnsfrd — Power transferred between blocks
`bus`

PwrTrnsfrd — Power transferred between blocks

Positive signals indicate flow into block
Negative signals indicate flow out of block

Dependencies

To create this input port, select Transferred power.

PwrNotTrnsfrd — Power crossing block boundary, not transferred
`bus`

PwrNotTrnsfrd — Power crossing the block boundary, but not transferred

Positive signals indicate an input
Negative signals indicate a loss

Dependencies

To create this input port, select Not transferred power.

PwrStored — Stored energy rate of change
`bus`

PwrStored — Stored energy rate of change

Positive signals indicate an increase
Negative signals indicate a decrease

Dependencies

To create this input port, select Stored power.

Output

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PwrInfo — Power information bus
`bus`

Power information bus

Parameters

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Block Options

Associated block — Associated block
`Parent` (default) | `Parent reference block`

When you add the Power Accounting Bus Creator to your plant block, you associate the signals to a parent block. There are two association methods.

Method Description Example

Method	Description	Example
`Parent`	Power Accounting Bus Creator associates the power bus signals with the parent block.	In the conventional vehicle reference application, navigate to the `Passenger Car > Engine > SiMappedEngine > Accessory Load Model` plant subsystem. Open the Power Accounting Bus Creator. The Associated block parameter is set to `Parent`, so the Power Accounting Bus Creator associates the power signals with the `Accessory Load Model` plant subsystem.
`Parent reference block`	Power Accounting Bus Creator associates the power bus signals with a reference block. Use the Library block name parameter to specify the block.	In the Ideal Fixed Gear Transmission block, navigate to the `Bus Creation` subsystem. Open the Power Accounting Bus Creator. The Power Accounting Bus Creator block uses these parameter settings to associate the power signals to the Ideal Fixed Gear Transmission block. Associated block parameter is set to `Parent reference block`. Library block name parameter is set to `'autolibsharedtransfixedgear/Ideal Fixed Gear Transmission'`.

Parent

Power Accounting Bus Creator associates the power bus signals with the parent block.

In the conventional vehicle reference application, navigate to the Passenger Car > Engine > SiMappedEngine > Accessory Load Model plant subsystem. Open the Power Accounting Bus Creator.

The Associated block parameter is set to Parent, so the Power Accounting Bus Creator associates the power signals with the Accessory Load Model plant subsystem.

Parent reference block

Power Accounting Bus Creator associates the power bus signals with a reference block.

Use the Library block name parameter to specify the block.

In the Ideal Fixed Gear Transmission block, navigate to the Bus Creation subsystem. Open the Power Accounting Bus Creator.

The Power Accounting Bus Creator block uses these parameter settings to associate the power signals to the Ideal Fixed Gear Transmission block.

Associated block parameter is set to Parent reference block.
Library block name parameter is set to 'autolibsharedtransfixedgear/Ideal Fixed Gear Transmission'.

Library block name — Block name
`Block name`

Dependencies

To create this parameter, set Associated block to Parent reference block.

Power Input Types

Transferred power — Power transferred between blocks
`on` (default) | `off`

Power transferred between blocks.

Dependencies

Selecting this parameter creates the:

PwrTrnsfrd input port
Transferred parameters

Not transferred power — Power crossing block boundary
`on` (default) | `off`

Power crossing block boundary, but not transferred.

Dependencies

Selecting this parameter creates the:

PwrNotTrnsfrd input port
Not Transferred parameters

Stored power — Stored energy rate of change
`on` (default) | `off`

Stored energy rate of change.

Dependencies

Selecting this parameter creates the:

PwrStored input port
Stored parameters

Transferred

Signal name — Name of signal
`char`

Signal name.

For example, this table summarizes the Power Accounting Bus Creator parameter Transferred parameter values for the listed blocks.

Block	Power Accounting Bus Creator Parameter Values
Block	Signal Name	Associated Port	Description
Ideal Fixed Gear Transmission	`PwrTrnsfrd.PwrDiffrntl`	`{'DiffTrq','DiffSpd'}`	`Differential`
Ideal Fixed Gear Transmission	`PwrTrnsfrd.PwrEng`	`{'EngTrq','EngSpd'}`	`Engine`
Gearbox	`PwrTrnsfrd.PwrBase`	`{{'BTrq','BSpd'}'B'}`	`Base input`
Gearbox	`PwrTrnsfrd.PwrFlwr`	`{{'FTrq','FSpd'}'F'}`	`Follower output`
Boost Drive Shaft	`PwrTrnsfrd.PwrCmpsr`	`'Cmpsr'`	`Compressor`
	`PwrTrnsfrd.PwrExt`	`'ExtTrq'`	`External`
	`PwrTrnsfrd.Turb`	`'Turb'`	`Turbine`

Associated Port — Name of ports that transfer power
`{'PortA','PortB','PortC'}`

Name of ports that transfer power.

For example, this table summarizes the Power Accounting Bus Creator parameter Transferred parameter values for the listed blocks.

Block	Power Accounting Bus Creator Parameter Values
Block	Signal Name	Associated Port	Description
Ideal Fixed Gear Transmission	`PwrTrnsfrd.PwrDiffrntl`	`{'DiffTrq','DiffSpd'}`	`Differential`
Ideal Fixed Gear Transmission	`PwrTrnsfrd.PwrEng`	`{'EngTrq','EngSpd'}`	`Engine`
Gearbox	`PwrTrnsfrd.PwrBase`	`{{'BTrq','BSpd'}'B'}`	`Base input`
Gearbox	`PwrTrnsfrd.PwrFlwr`	`{{'FTrq','FSpd'}'F'}`	`Follower output`
Boost Drive Shaft	`PwrTrnsfrd.PwrCmpsr`	`'Cmpsr'`	`Compressor`
	`PwrTrnsfrd.PwrExt`	`'ExtTrq'`	`External`
	`PwrTrnsfrd.Turb`	`'Turb'`	`Turbine`

Description — Signal description
`char`

Signal description.

For example, this table summarizes the Power Accounting Bus Creator parameter Transferred parameter values for the listed blocks.

Block	Power Accounting Bus Creator Parameter Values
Block	Signal Name	Associated Port	Description
Ideal Fixed Gear Transmission	`PwrTrnsfrd.PwrDiffrntl`	`{'DiffTrq','DiffSpd'}`	`Differential`
Ideal Fixed Gear Transmission	`PwrTrnsfrd.PwrEng`	`{'EngTrq','EngSpd'}`	`Engine`
Gearbox	`PwrTrnsfrd.PwrBase`	`{{'BTrq','BSpd'}'B'}`	`Base input`
Gearbox	`PwrTrnsfrd.PwrFlwr`	`{{'FTrq','FSpd'}'F'}`	`Follower output`
Boost Drive Shaft	`PwrTrnsfrd.PwrCmpsr`	`'Cmpsr'`	`Compressor`
	`PwrTrnsfrd.PwrExt`	`'ExtTrq'`	`External`
	`PwrTrnsfrd.Turb`	`'Turb'`	`Turbine`

Not Transferred

Signal name — Name of signal
`char`

Signal name.

For example, this table summarizes the Power Accounting Bus Creator parameter Not Transferred parameter values for the listed blocks.

Block	Power Accounting Bus Creator Parameter Values
Block	Signal Name	Description
Ideal Fixed Gear Transmission	`PwrNotTrnsfrd.PwrDampLoss`	`Damping loss`
Ideal Fixed Gear Transmission	`PwrNotTrnsfrd.PwrEffLoss`	`Efficiency loss`
Gearbox	`PwrNotTrnsfrd.PwrDampLoss`	`Damping loss`
Gearbox	`PwrNotTrnsfrd.PwrMechLoss`	`Mechanical loss`
Boost Drive Shaft	`PwrNotTrnsfrd.PwrMechLoss`	`Mechanical loss`

Description — Signal description
`char`

Signal description.

For example, this table summarizes the Power Accounting Bus Creator parameter Not Transferred parameter values for the listed blocks.

Block	Power Accounting Bus Creator Parameter Values
Block	Signal Name	Description
Ideal Fixed Gear Transmission	`PwrNotTrnsfrd.PwrDampLoss`	`Damping loss`
Ideal Fixed Gear Transmission	`PwrNotTrnsfrd.PwrEffLoss`	`Efficiency loss`
Gearbox	`PwrNotTrnsfrd.PwrDampLoss`	`Damping loss`
Gearbox	`PwrNotTrnsfrd.PwrMechLoss`	`Mechanical loss`
Boost Drive Shaft	`PwrNotTrnsfrd.PwrMechLoss`	`Mechanical loss`

Stored

Signal name — Name of signal
`char`

Signal name.

For example, this table summarizes the Power Accounting Bus Creator parameter Stored parameter values for the listed blocks.

Block	Power Accounting Bus Creator Parameter Values
Block	Signal Name	Description
Ideal Fixed Gear Transmission	`PwrStored.PwrStoredTrans`	`Rotational`
Control Volume System	`PwrStored.PwrHeatStored`	`Stored heat`
Datasheet Battery	`PwrStored.PwrStoredBatt`	`Battery stored`

Description — Signal description
`char`

Signal description.

For example, this table summarizes the Power Accounting Bus Creator parameter Stored parameter values for the listed blocks.

Block	Power Accounting Bus Creator Parameter Values
Block	Signal Name	Description
Ideal Fixed Gear Transmission	`PwrStored.PwrStoredTrans`	`Rotational`
Control Volume System	`PwrStored.PwrHeatStored`	`Stored heat`
Datasheet Battery	`PwrStored.PwrStoredBatt`	`Battery stored`

Extended Capabilities

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

Version History

Introduced in R2019a

Power Accounting Bus Creator