Field oriented control Induction motor drive

[Damegruev]

Hi everyone,

I am trying to simulate an Field oriented control Induction motor drive (AC3 model from simulink),but the library contains only two models, 3 hp and 200 hp drive parameter sets.

The motors which i want to simulate are 30 Kw and 37 Kw ( 40 hp and 50 hp), but i don't know the drive parameter sets. (asynchronous machine, converters and BUS and controller).

Most of these i need Rs,Rr,Lsl,Lrl,Lm,p,J,Bm.

So i would like to ask you if you could help me with this? How can i calculate these parameters? Can i find these preset parameters somewhere?


Thank you in advance.

Sincerely,

Goce

 

[electricpete]

Most of these i need Rs,Rr,Lsl,Lrl,Lm,p,J,Bm.

So i would like to ask you if you could help me with this? How can i calculate these parameters? Can i find these preset parameters somewhere?

Rs,Rr,Lsl,Lrl,Lm can be estimated. The more info available to estimate, the better they can be estimated. It amounts to something of a "best fit". (We can calculate performance parameters from circuit parameters, so our job is to find the set of unknown circuit parameters which reproduce the known performance parameters). Do you have motor namplate data? That certainly provides data for an estimate. If you have additional test report data such as no-load current and also efficiency/pf at 50% that can help. If you'll post available info here I'll give a try and post my spreadsheet (easier to show an example than to try to explain how).

p = poles? Known from nameplate speed and frequency.

J = rotating inertia? Nema provides some thumbules for that which I can provide if that's what you're after based on horsepower and speed. Note it applies to motor only... what you're driving may need to be added.

Bm = ?


=====================================
(2B)+(2B)' ?

 

[LiteYear]

I have a similar issue when using the Motor Drive Module in PSIM. It can be difficult to come up with realistic values to allow a simulation to run if your interest is in things other than the motor. If you have the luxury of having access to the motor, you could just measure them, but I gather this is not your situation.

You can make a start by interpolating between your 3hp and 200hp figures. I effectively done this and built up a table for the typical motor sizes we deal with. The numbers are far from precise, but enough to get it "spinning" in simulation.

I agree with electricpete's interpretation of the variables - Rs, Rr, Lsl, Lrl, Lm are all motor winding parameters (stator and rotor resistances and inductance, and magnetising inductance). p is the number of poles (eg. 2 for a 3000/3600rpm motor or 4 for a 1500rpm/1800rpm motor) and J is the moment of inertia in kg.m^2 (as low as 0.05 for just the motor itself at that power level). I also don't recognise Bm. Very interested to see the spreadsheet.

 

[Damegruev]

Thanks for your reply.

Here's the motor parameters which i read from the nameplate: 30 Kw; 56,6 A; 190,9 Nm; 380 V; 50 Hz; 1468 r/min; IP 54; p=4.


Considering the motor parameters for 200 HP and 3 Hp from Simulink library, there are as following:


Model AC3 200 Hp Model AC3 3 Hp
Electrical parameters: Electrical parameters:

Power = 159.2 Kw Power = 2238 VA
Voltage = 460 V Voltage = 220 V
Frequency = 60 Hz Frequency = 60 Hz
Stator resistance = 0.01485 Ω Stator resistance = 0.435 Ω
Leakage stator inductance = 0.0003027 H Leakage stator inductance = 0.002 H
Rotor resistance = 0.009295 Ω Rotor resistance = 0.816 Ω
Leakage rotor inductance = 0.0003027 H Leakage rotor inductance = 0.002 H
Mutual inductance = 0.01046 H Mutual inductance = 0.06931 H

Mechanical parameters: Mechanical parameters:

J = 3.1 kg•m^2 J = 0.089 kg•m^2
Bm (friction factor) = 0.08 N•m•s Bm (friction factor) = 0.005 N•m•s
P = 2 poles P = 2 poles

Initial values: Initial values:
Slip =1 Slip =1

Can we interpolate them because the range from one to the another motor is too big??