Field Oriented Controller

Category: Toolbox > eDrives > Controllers

Inputs:

•      freq_n: Normalized frequency reference. Scaled Integer (2.32)

•      id_ref: Normalized d-axis current reference. Scaled Integer (2.32).

•      iqref: Normalized q-axis current reference. Scaled Integer (2.32)

•      i_a: Normalized measured alpha-axis current. Scaled Integer (2.32).

•      i_b: Normalized measured beta-axis current. Scaled Integer (2.32)

•      theta_n: Normalized theta (angle) measured. See Quadrature Encoder.

•      udc_n: Normalized measured DC bus voltage. Scaled Integer (2.32)

•      kpn: Normalized proportional gain Kp for speed loop. Scaled Integer (8.32)

•      kin: Normalized integral gain Ki for speed loop. Scaled Integer (8.32)

•      Speed_loop_on: Speed loop enable. (binary input)

•      FOC_On: Field Oriented Control / Current Loop enable. (binary input)

•      cntr_on: Controller enable. (binary input)

Outputs:

•      mA_ref: Modulation index reference for phase A. Scaled Integer (8.32)

•      mB_ref: Modulation index reference for phase B. Scaled Integer (8.32)

•      mC_ref: Modulation index reference for phase C. Scaled Integer (8.32)

•      speed_n: Normalized measured speed. Scaled Integer (8.32)

•      isq_n: Normalized q-axis quadrature current used to calculate the shaft torque  %FontSize=10 %TeXFontSize=10 \documentclass{article} \usepackage{amsmath} \pagestyle{empty} \begin{document} $ T_{me}=\frac{3}{2}\,p\,\psi\,i_q $ \end{document}, with pole pair p, rotor flux %FontSize=10 %TeXFontSize=10 \documentclass{article} \usepackage{amsmath} \pagestyle{empty} \begin{document} $ \psi $ \end{document} and quadrature current %FontSize=10 %TeXFontSize=10 \documentclass{article} \usepackage{amsmath} \pagestyle{empty} \begin{document} $ i_q=i_{qn}\,c_{fs} $ \end{document}. Scaled Integer (8.32)

Description: The Field Oriented Controller block generates modulation indices for three phase motor voltages. It uses both a speed loop and a current loop. It uses the rotor position and measured currents as feedback. It can be used with a Quadrature Encoder or Hall Sensor.

All inputs are divided by their respective full-scale values to get normalized values. For example, id_n = id_ref/C_fs, where id_ref is the user input and C_fs is the full-scale current.

Graphical user interface, table Description automatically generated

Current Controller Kp (V/A): Indicates the proportional gain for the current loop.

Current Controller wi (rad/s): Indicates the bandwidth of the current controller. Typically limited to 2000 rad/s.

Full-scale Current (A): Indicates the full-scale current value for normalization.

Full-scale Freq (Hz): Indicates the full-scale frequency value for normalization.

Full-scale Voltage (V): Indicates the full-scale voltage value for normalization.

Max Modulation Index: Indicates the maximum modulation index value (absolute), which is the radius of a circle in the %FontSize=10 %TeXFontSize=10 \documentclass{article} \usepackage{amsmath} \pagestyle{empty} \begin{document} $ \alpha,\,\beta $ \end{document} plane.

Motor Pole Pairs: Indicates the number of magnetic pole pairs of the motor.

PM Flux Estimated (Wb): Indicates the estimated or calculated permanent magnetic flux of the motor used.

Sampling Freq (Hz): Used by the controller. This should set to the same frequency as set in System > System Properties.

Speed Controller Limit (A): Indicates the current limit for q-axis reference current used by the speed controller.

Speed Loop Freq/Sampling Freq: This ratio helps set the frequency at which the speed loop operates.

User Current Ramp (A/s): Indicates the safety limit to avoid sudden jerks in the input current values .

User Frequency Ramp (Hz): Indicates the safety limit to avoid sudden jerks in the input frequency values.