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ASM Field-Oriented Control

Asynchronous machine field-oriented control

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  • Simscape / Power Systems / Simscape Components / Control / ASM Control

Description

The ASM Field-Oriented Controller block implements an asynchronous machine (ASM) field-oriented control (FOC) structure using the per-unit system. To decouple the torque and flux, FOC uses the rotor d-q reference frame. The figure shows the control structure.

In the diagram:

  • ωr is the measured angular velocity.

  • ωref is the reference angular velocity.

  • id and iq are the d- and q-axis stator currents.

  • ia, ib, and ic are the a-, b- and c-phase stator winding currents.

  • imr_ref is the reference magnetizing current.

  • imr is the magnetizing current.

  • vd and vq are the d- and q-axis stator voltages.

  • va, vb, and vc are the a-, b- and c-phase stator winding voltages.

  • θe is the rotor electrical angle.

  • GAH, GAL, GBH, GBL, GCH, and GCL are the a-, b- and c-phase high (H) and low(L) gate pulses.

Assumptions and Limitations

  • The machine parameters are known.

  • The implementation uses the per-unit system.

  • The control structure implementation uses a single sample rate.

Ports

Input

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Magnetizing reference current in the per-unit system.

Data Types: single | double

Rotor reference velocity in per-unit system.

Data Types: single | double

Measured phase currents in the per-unit system.

Data Types: single | double

Measured angular velocity in per-unit system.

Data Types: single | double

Measured dc-link voltage, in V.

Data Types: single | double

Output

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Inverter gate pulses. The block does not consider any dead time.

Data Types: single | double

Bus containing signals for visualization.

Data Types: single | double | bus

Parameters

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General

Nominal voltage.

Nominal electrical frequency.

Rotor, stator-side resistance in the per-unit system.

Rotor stator-side leakage inductance, in the pu-unit system.

Magnetizing inductance in the per-unit system.

Time constant for filtering the d and q currents.

Voltage threshold to activate the power inverter.

Fundamental sample time must be less than the control sample time.

Control sample time must be greater than the fundamental sample time.

Outer Loop

Proportional gain for the magnetizing current controller.

Integral gain for the magnetizing current controller.

Integral anti-windup gain for the magnetizing current controller.

Proportional gain for the speed controller.

Integral gain for the speed controller.

Integral anti-windup gain for the speed controller.

Maximum current for the d-axis.

Maximum current for the q-axis.

Inner Loop

Align the a-phase vector of the abc reference frame to the d- or q-axis of the rotating reference frame.

Proportional gain of the PI controller used for direct-axis current control.

Integrator gain of the PI controller used for direct-axis current control.

Anti-windup gain of the PI controller used for direct-axis current control.

Proportional gain of the PI controller used for quadrature-axis current control.

Integrator gain of the PI controller used for quadrature-axis current control.

Anti-windup gain of the PI controller used for quadrature-axis current control.

Prioritize or maintain ratio between d- and q-axes when block limits voltage.

PWM

Specify the waveform technique.

The sampling mode determines whether the block samples the modulation waveform when the waves intersect or when the carrier wave is at one or both of its boundary conditions.

Specify the rate at which you want the switches in the power converter to switch.

Introduced in R2017b

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