ACIM Parameter Estimation Configurator

Generate configuration elements for AC induction motor (ACIM) parameter estimation

Since R2023a

• 

Libraries:
Motor Control Blockset / Parameter Estimation / ACIM Parameter Estimation

Description

The ACIM Parameter Estimation Configurator block generates the following configuration elements for estimating the parameters of an AC induction motor:

• Elements for motor and inverter hardware

• Elements for estimating magnetizing current I_d0

• Elements for estimating motor resistance (R_s)

• Elements for estimating:

  • Rotor resistance, R_r

  • Magnetizing inductance, L_m

  • Stator leakage inductance, L_ls

  • Rotor leakage inductance, L_lr

• Elements for estimating motor inertia (J) and friction constant (B)

The block uses the parameter settings to generate an output bus containing the configuration elements. You can use the configuration elements in these ACIM parameter estimation blocks:

• Id0 Estimator

• ACIM Rs Estimator

• RrL Estimator

• ACIM Mechanical Parameter Estimator

Examples

Estimate Induction Motor Parameters Using Parameter Estimation Blocks

Uses the parameter estimation blocks provided by Motor Control Blockset™ to estimate these parameters of an AC induction motor (ACIM):

• Open Model

Ports

Output

Config — Bus signal

bus

The bus signal includes these configuration elements.

Category	Configuration element			Units
Elements for motor and inverter hardware	Number of pole pairs			-
	Rated frequency			Hz
	Nominal motor current			A
	Nominal voltage			V
	Maximum measurable inverter current			A
	Board resistance			ohm
	Current sense gain			A/ADC Count
	Voltage sense gain			V/ADC Count
Elements for estimating magnetizing current Id0	Measurement time			seconds
	Open-loop ramp time			seconds
Elements for estimating motor resistance (Rs)	Estimation time			seconds
	Vd reference voltage 1			PU voltage
	Vd reference voltage 2			PU voltage
Elements for estimating rotor resistance (Rr), magnetizing inductance (Lm), stator leakage inductance (Lls), and rotor leakage inductance (Llr)	Frequency 1 as a ratio of rated frequency			PU frequency
	Frequency 2 as a ratio of rated frequency			PU frequency
	High frequency for Lm			Hz
	Start voltage for voltage sweep			PU voltage
	Voltage step for voltage sweep			PU voltage
	High-frequency injection voltage			PU voltage
Elements for estimating motor inertia (J) and friction constant (B)	Closed-loop speed duration			seconds
	Closed-loop speed			RPM
	Iq Reference current for FOC			PU current
	Proportional gain			-
	Integral gain			-
	Lower speed limit for inertia estimation			RPM
-	Parameter estimation sample time			seconds

The configuration elements are analogous to the block parameters. For more information about these elements, see Parameters.

Data Types: single

Parameters

Motor and Inverter

Number of pole pairs — Number of motor pole pairs

2 (default) | scalar

Number of pole pairs available in the induction motor.

Rated frequency (Hz) — Motor rated frequency

50 (default) | scalar

Rated frequency of the induction motor (in Hertz).

Nominal motor current (A) — Motor nominal current

2 (default) | scalar

Rated current of the induction motor (in Amperes).

Nominal voltage (V) — Motor nominal voltage

24 (default) | scalar

Rated voltage of the induction motor (in Volts).

Maximum inverter current (A) — Maximum measurable current

21 (default) | scalar

Maximum current (in Amperes) that the system (including inverter and controller) can measure.

Board resistance (ohm) — Inverter bridge resistance

0.0043 (default) | scalar

Resistance in the path of phase currents (excluding motor resistance). You can obtain this value from the datasheet of the inverter hardware.

Current sense gain (A/ADC Count) — Current per ADC count

0.0105 (default) | scalar

Gain of the current sense circuit of the inverter. This value determines the current (in Amperes) corresponding to one analog-to-digital converter (ADC) count (resolution of the measurable current range).

Voltage sense gain (V/ADC Count) — Voltage per ADC count

0.0098 (default) | scalar

Gain of the voltage sense circuit of the inverter. This value determines the voltage (in Volts) corresponding to one analog-to-digital converter (ADC) count (resolution of the measurable voltage range).

Id0 Estimation

Measurement time (sec) — Time used to measure and average-out current

5 (default) | scalar

Time used to measure and average-out the peaks in the current response to the open-loop operation of the induction motor. For more details about I_d0 estimation, see Id0 Estimator.

Open loop ramp time (sec) — Time allotted to ramp up frequency

3 (default) | scalar

Time that you want to allot for the motor operation frequency to ramp up and reach 90 percent of the motor rated frequency. For more details about I_d0 estimation, see Id0 Estimator.

Rs Estimation

Estimation time (sec) — Time to run R_s estimation algorithm

2 (default) | scalar

Time that you want to allot to run the motor resistance (R_s) estimation algorithm. This value defines the time duration for which the ACIM Rs Estimator block injects each voltage to measure the motor resistance. For more details about R_s estimation, see ACIM Rs Estimator.

Vd reference voltage 1 (PU) — First reference voltage for R_s estimation

0.1 (default) | scalar

The first reference motor-phase voltage (in per-unit) that the ACIM Rs Estimator block uses for measuring motor resistance (R_s). By default, the block sets this field to 10 percent of the inverter DC voltage. For more details about R_s estimation, see ACIM Rs Estimator. For more details about the per-unit system, see Per-Unit System.

Vd reference voltage 2 (PU) — Second reference voltage for R_s estimation

0.2 (default) | scalar

The second reference motor-phase voltage (in per-unit) that the ACIM Rs Estimator block uses for measuring motor resistance (R_s). By default, the block sets this field to 20 percent of the inverter DC voltage. For more details about R_s estimation, see ACIM Rs Estimator. For more details about the per-unit system, see Per-Unit System.

Rr, Lm, Lls, Llr Estimation

Frequency 1 as a ratio of rated frequency (PU) — Ratio of first injected low frequency over rated frequency

0.1 (default) | scalar

Ratio of the first injected low frequency over the rated frequency of the induction motor (in per-unit). For more details about the estimation process, see RrL Estimator. For more details about the per-unit system, see Per-Unit System.

Frequency 2 as a ratio of rated frequency (PU) — Ratio of second injected low frequency over rated frequency

0.2 (default) | scalar

Ratio of the second injected low frequency over the rated frequency of the induction motor (in per-unit). For more details about the estimation process, see RrL Estimator. For more details about the per-unit system, see Per-Unit System.

High Frequency for Lm (Hz) — Frequency of third injected signal

200 (default) | scalar

Frequency of the third (high frequency) signal (in Hertz) injected by the block for mechanical parameter estimation. For more details about the estimation process, see RrL Estimator.

Voltage sweep start value voltage (PU) — Initial voltage at which voltage sweep begins

0.1 (default) | scalar

Initial voltage (of the first and second low-frequency signals that the block injects, in per-unit) at which the voltage sweep begins. For more details about the estimation process, see RrL Estimator. For more details about the per-unit system, see Per-Unit System.

Voltage sweep step value voltage (PU) — Step size for voltage sweep

0.0125 (default) | scalar

Step size that the block uses to perform voltage sweep on the two injected low frequency signals (in per-unit). For more details about the estimation process, see RrL Estimator. For more details about the per-unit system, see Per-Unit System.

High frequency injection voltage (PU) — Voltage of third injected signal

0.1 (default) | scalar

Voltage of the third (high frequency) signal (in per-unit) injected by the block for mechanical parameter estimation. For more details about the estimation process, see RrL Estimator. For more details about the per-unit system, see Per-Unit System.

Current measurement delay (s) — Delay in current measurement

2 * 50e-6 (default) | scalar

Time delay between an instance of current change and the point of time when the changed current is measured in the microcontroller.

J, B Estimation

Closed loop duration (sec) — Closed-loop motor run duration

5 (default) | scalar

Duration (in seconds) for which the ACIM Mechanical Parameter Estimator block runs the motor using closed-loop control before initiating coast-down. For more information about the estimation process, see ACIM Mechanical Parameter Estimator.

Closed loop speed (RPM) — Closed-loop motor speed

950 (default) | scalar

Speed (in RPM) at which the ACIM Mechanical Parameter Estimator block runs the motor using closed-loop control. For more information about the estimation process, see ACIM Mechanical Parameter Estimator.

Iq reference current for FOC (PU) — Reference current for FOC when estimating J and B

0.2 (default) | scalar

Reference current, I_q, to achieve the reference speed specified in the Closed loop speed (RPM) parameter. For more information about the estimation process, see ACIM Mechanical Parameter Estimator.

Specify current controller gains — Specify PI current controller gains

off (default) | on

Select this parameter to enable these fields:

• Proportional gain

• Integral gain

You can use these fields to enter the proportional and integral gains of the PI current controllers that implement closed-loop control to estimate J and B.

If you clear this parameter, the block automatically computes the proportional and integral gains.

To know more about the estimation process, see ACIM Mechanical Parameter Estimator.

Proportional gain — Proportional gain of PI controller

1 (default) | scalar

Proportional gain, k_p, of the PI current controller that implements field-oriented control to run the motor in closed-loop control and estimate J and B.

Dependencies

To enable this parameter, select the Specify current controller gains parameter.

Integral gain — Integral gain of PI controller

1000 (default) | scalar

Integral gain, k_i, of the PI current controller that implements field-oriented control to run the motor in closed-loop control and estimate J and B.

Dependencies

To enable this parameter, select the Specify current controller gains parameter.

Speed lower limit for inertia estimation (RPM) — Lower speed limit during coast-down

100 (default) | scalar

Lower speed limit during coast-down at which the ACIM Mechanical Parameter Estimation block registers the timestamp for estimating motor inertia. For more details about the estimation process, see ACIM Mechanical Parameter Estimation.

Parameter estimation sample time (sec) — Sample time for parameter estimation

50e-6 (default) | scalar

Sample time for the parameter estimation algorithm. This parameter defines the sample time for these parameter estimation blocks for AC induction motors:

• Id0 Estimator

• ACIM Rs Estimator

• Rr L Estimator

• ACIM Mechanical Parameter Estimator

Extended Capabilities

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

Version History

Introduced in R2023a