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The PMSM SH model defines the Inductance Matrices Ld and Lq within a three-dimensional table stored in an RTT motor model file.  Because the tables are three-dimensional rather than two-dimensional, the PMSM SH model can provide higher fidelity than the PMSM BLDC model.  Please see Permanent Magnet Synchronous Machine Models Comparison for a comparison of the PMSM SH and PMSM BLDC models.

Configuration Page

In the System Explorer window configuration tree, expand the Power Electronics Add-On custom device and select Circuit Model >> PMSM SH to display this page.  Use this page to configure the PMSM SH machine model. 

This page includes the following components, configurable at edit-time only:

Machine Model Settings
NameSpecifies the name of the machine model.
DescriptionSpecifies a description for the machine model.
Motor Configuration
Model File

Specifies the path to the 3D Motor Model file on disk. Refer to JMAG-RT RTT File Generation Recommendations for details regarding the file format. The following standards are supported:

    • ANSYS (.txt)
    • JMAG (.rtt)
EnableEnables the motor to execute. By default, the first PMSM SH instance is enabled, however, it is recommended to disable unused motors for an optimal timestep.
Initial Angle (Deg)

Initial Angle of the machine

This may be useful when simulating two separate 3-phase machines that require a phase shift between them.

Enable Advanced Channels

Allows certain parameters to be exposed as tunable VeriStand Channels. See the Advanced Channels section below for more details.

This checkbox is only available when the machine is enabled. Otherwise, the option is greyed out.

Solver Timestep (s)

The timestep at which the machine model executes

Every Ts, new outputs are computed by the FPGA machine model. By default, this is set to the minimum achievable timestep.

Table Max Current (Amp)

Maximum current value that will be used to interpolate the model file. Use this feature to increase the resolution of the machine at lower Current operating points. This will reduce the machine operating range. Use -1 to use the full range available in model file.

DQ Angle Offset (Degrees)

Specifies the electrical angle offset θoffset as described by the equation below 

Anchor
ElectricalAngle
ElectricalAngle
LaTeX Math Block
\theta_e= pp * \theta_m + \theta_{offset}

By default, this parameter is set to 0 degrees, which indicates the the D axis is aligned with Phase A when the rotor angle θ=0.

Setting this parameter to -90 Degrees indicates that the Q axis is aligned with Phase A when the rotor angle θ=0.

Input Mapping Configuration
Use the Input Mapping Configuration to route signals to the Voltage Phase A, Voltage Phase B, and Voltage Phase C inputs of the machine model.  Available routing options may vary depending on the selected Hardware Configuration.

Group

Specifies the group that will be routed to the input voltages of the machine. The available routing options are defined by the selected Hardware Configuration, however it is typical to see the following options by default:

  • Measurements - eHS circuit model measurements

Element

Specifies the index of the measurement in the group that has been selected as the input voltage of the machine.


Section Channels

This section includes the following custom device channels:

Channel Name

Symbol

Type

Units

Default Value

Description

Current Phase A

IaOutputAmpere0 APhase A current measured at the stator

Current Phase B

IbOutputAmpere0 APhase B current measured at the stator

Current Phase C

IcOutputAmpere0 APhase C current measured at the stator
Average Voltage Phase AVa,avgOutputVolts0 V

Averaged Phase A voltage measured at the stator. The voltage is processed through a low-pass filter with a cutoff frequency of 159 Hz

LaTeX Math Block
anchorVCutoffFrequency
alignmentleft
f_{c} = \frac{1}{2\pi \times 1e-3} = 159Hz 


Average Voltage Phase BVb,avgOutputVolts0 VAveraged Phase B voltage measured at the stator. The voltage is processed through a low-pass filter with a cutoff frequency of 159 Hz
Average Voltage Phase CVc,avgOutputVolts0 VAveraged Phase C voltage measured at the stator. The voltage is processed through a low-pass filter with a cutoff frequency of 159 Hz
Three-Phase Active PowerPOutputWatts0 W

Three-phase instantaneous active electrical power in Watts

See Power Equations for more information on how this is calculated.

Three-Phase Reactive PowerQOutputVolt-ampere reactive0 var

Three-phase instantaneous reactive electrical power in vars

See Power Equations for more information on how this is calculated.

Direct Axis Stator CurrentIdOutputAmpere0 A

Direct-axis stator current in the reference frame aligned with the rotor

For a description of the DQ-transform used to compute this value, see D-Q Transform

Quadrature Axis Stator CurrentIqOutputAmpere0 A

Quadrature-axis stator current in the reference frame aligned with the rotor

For a description of the DQ-transform used to compute this value, see D-Q Transform

Electrical AngleθeOutputDegrees-90°

Position of the rotating magnetic field, defined by the electrical angle equation

Info

If this signal is routed to a Waveform Channel or an Analog Output Channel, its value is expressed in Turns.  The signal ranges in value from 0 to 1, with 1 representing a full rotation.


Electromagnetic TorqueTeOutputNm0 Nm

Torque generated through power at the stator. For equations describing the electromagnetic torque of each type of machine, refer to their specific description pages under the Machine Section.

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#AdvancedSHChannels
#AdvancedSHChannels
Advanced Channels

The following VeriStand channels are displayed under the Advanced section when the Enable Advanced Channels option is enabled on the PMSM SH configuration page. The value of an input channel can be modified dynamically at execution time. 

Channel Name

Symbol

Type

Units

Default Value

Description

Enable Resistance Override
Input
False

Enables the Resistance Phase A Override, Resistance Phase B Override, and Resistance Phase C Override channels, allowing the user to modify the phase resistances of the machine while the simulation is running.

When True, the phase resistances of the machine are read from the Resistance Phase A Override, Resistance Phase B Override, and Resistance Phase C Override channels.

When False, the phase resistances are read from the table in the 3D Motor Model File (JMAG .rtt or ANSYS .txt)

Enabling these channels allows the user to reduce the machine signal error in high impedance conditions. Refer to the procedure on How to Reduce PMSM SH Signal Error In High Impedance Conditions for more information.

Resistance Phase A OverrideRaInputOhm0.12 Ω

Phase A resistance of the machine

When Enable Resistance Override is True, this value overrides the Phase A resistance value defined in the 3D Motor Model File (JMAG .rtt or ANSYS .txt).

When Enable Resistance Override is False, this channel is not used.

This channel value can be modified while the simulation is running.

Resistance Phase B OverrideRbInputOhm0.12 Ω

Phase B resistance of the machine

When Enable Resistance Override is True, this value overrides the Phase B resistance value defined in the  3D Motor Model File (JMAG .rtt or ANSYS .txt).

When Enable Resistance Override is False, this channel is not used.

This channel value can be modified while the simulation is running.

Resistance Phase C OverrideRcInputOhm0.12 Ω

Phase C resistance of the machine

When Enable Resistance Override is True, this value overrides the Phase C resistance value defined in the  3D Motor Model File (JMAG .rtt or ANSYS .txt).

When Enable Resistance Override is False, this channel is not used.

This channel value can be modified while the simulation is running.

Model Description

Permanent Magnet Synchronous Machines are common electrical machines in the the automotive and transportation industry. The PMSM is usually chosen because of its excellent power density (produced power over size or weight) or its capability to reach higher speed than others motor types. However, controlling a PMSM is usually more challenging when compared to other machine types. Since it is a synchronous machine, the controller must be aware of the rotor position at all times in order to properly control the torque. In addition, there is a chance of de-fluxing the magnet if the control is not stable, which would lead to a modification of the machine properties. 

The following figures illustrate the equivalent circuits of the PMSM motor model in the abc-frame and in the D-Q frame.


Figure 1.  Electrical Model for PMSM

Figure 2.  Electrical Model for PMSM in the D-Q frame

where Labc are the phase inductances, Rabc are the stator resistances, Vabc are the instantaneous voltages across the stator windings, Vbemf,abc are the phase to neutral voltages induced by the electromotive forces, Vdq are the direct-axis and quadrature-axis stator voltages in the reference frame aligned with the rotor, Ldq are the direct-axis and quadrature-axis inductances of the machine, ωe  is the electrical speed of the machine, and ψM is the permanent magnet flux linkage

Excerpt Include
PMSM BLDC Section
PMSM BLDC Section
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