Estimate rotor resistance (Rr), magnetizing inductance (Lm), stator leakage inductance (Lls), and rotor leakage inductance (Llr) of AC induction motor (ACIM)
Motor Control Blockset / Parameter Estimation / ACIM Parameter Estimation
The RrL Estimator block computes the rotor resistance (Rr), magnetizing inductance (Lm), stator leakage inductance (Lls), and rotor leakage inductance (Llr) of an AC induction motor using the phase currents, DC voltage across the motor, and the test configuration elements.
To estimate these values, the block injects the following three signals across the motor phases:
First low-frequency signal (of varying voltage)
Second low-frequency signal (of varying voltage)
High-frequency signal (of fixed voltage)
Using the given initial voltage and the step size, the block performs a voltage sweep on the first and second low-frequency signals until the resulting motor phase current becomes equal to 50 percent of the motor rated current. At this point, the block measures the phase difference between the injected voltage (of the low-frequency signals) and the resulting current response to estimate Rr, Lm, Lls, and Llr.
Iabc — Three-phase current response
The three-phase current response of the motor measured by the current sensors.
Providing phase-c current input is optional. The block functionality is not impacted if you do not provide the phase-c current input.
Vdc — DC link voltage
DC bus voltage that you provide to the inverter.
StartStop — Control signal for Ld estimation
Signal that either starts or stops the estimation process:
1(rising edge of a pulse) — This signal initiates the estimation process.
0(falling edge of a pulse) — This signal immediately stops the estimation process. If you interrupt the estimation process abruptly before completion, the block does not compute or output the Rr, Lm, Lls, and Llr values.
Config — Bus signal input
This table summarizes the expected configuration elements in the bus signal input.
Elements for motor and inverter hardware
Number of pole pairs
Nominal motor current
Maximum measurable inverter current
Current sense gain
Voltage sense gain
Elements for estimating magnetizing current Id0
Open-loop ramp time
Elements for estimating motor resistance (Rs)
Vd reference voltage 1
Vd reference voltage 2
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
Frequency 2 as a ratio of rated frequency
|High frequency for Lm|
Start voltage for voltage sweep
Voltage step for voltage sweep
High-frequency injection voltage
Elements for estimating motor inertia (J) and friction constant (B)
Closed-loop speed duration
Iq Reference current for FOC
Lower speed limit for inertia estimation
Parameter estimation sample time
You can connect this input port to the
Config output port of
the ACIM Parameter Estimation Configurator block.
Vabc — a, b, and c-axis stator
reference voltage components
Stator reference voltage components along the a, b, and c axes of the abc reference frame.
Rr — Estimated rotor resistance
Estimated rotor resistance of the induction motor (in Ohms).
Lm — Estimated magnetizing inductance
Estimated magnetizing inductance of the induction motor (in Henry).
Lls — Estimated stator leakage inductance
Estimated stator leakage inductance of the induction motor (in Henry).
Llr — Estimated rotor leakage inductance
Estimated rotor leakage inductance of the induction motor (in Henry).
Log — Debug signals
Debug signals that the block provides for examination. The bus includes these debug signals.
Frequency that the block currently injects
|Did not complete estimation|
|Estimation completed successfully|
C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.
Introduced in R2023a