[SOLVED] Questions about phase inductance and phase resistance in FOC Code

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User13848
Level 1
Level 1
Hi I have some questions about FOC.

In the example code, we know that we set the Phase Resistance to 0.36 ohm and the Phase Inductance to 0.0002H. And what motor was used was confirmed in Abstract.txt.

1. Is Phase Resistance the half of Line to Line Resistance?
2. Can I obtain the phase resistance value using the stator resistance value?
If I can get it, let me know how to get it.
3. I want to know how to obtain the value of phase inductance.
4. I want to know how to obtain phase inductance using direct axis inductance.

Regards,
Rocky
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3 Replies
Mc-Key
Employee
Employee
Welcome!
Hi Rocky,

The FOC democode is expecting the motor windings in a star connection.
Answering your questions:

1) Yes, the Phase resistance is half of the Line to Line resistance

2) There is no distinction between stator and rotor resistance value in the code

3) it is possible to measure the phase inductunce in several ways:
- measure it with a LCR-Meter
- Apply a 50% dutycycle PWM-pattern, measure di/dt with a current Probe and calculate L

4) For this point, I have to reference the literature: "Permanent Magnet Synchronous and Brushless DC Motor Drives" from Ramu Krishnan
On Page 35, he gives a hint:

- Generally, the ratio is in a range of 3
- Earlier in the book he writes Ld > Lq

My proposal is to start with this relations.
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User13848
Level 1
Level 1
thank you for your kind reply
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User13848
Level 1
Level 1
Mc-Key wrote:
Hi Rocky,

The FOC democode is expecting the motor windings in a star connection.
Answering your questions:

1) Yes, the Phase resistance is half of the Line to Line resistance

2) There is no distinction between stator and rotor resistance value in the code

3) it possible to measure the phase inductunce in several ways:
- measure it with a LCR-Meter
- Apply a 50% dutycycle PWM-pattern, measure di/dt with a current Probe and calculate L

4) For this point, I have to reference the literature: "Permanent Magnet Synchronous and Brushless DC Motor Drives" from Ramu Krishnan
On Page 35, he gives a hint:

- Generally, the ratio is in a range of 3
- Earlier in the book he writes Ld > Lq

My proposal is to start with this relations.


and how to change this thread to [SOLVED]?
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