Computation of Rectified DC Current at constant DC Voltage for 1Ph AC Generator using Periodicity

Dattu B. Pawar

I am Computing  Rectified DC Current at constant DC Voltage for 1Ph AC Generator using Periodic model in flux 3D, I would like to know  if e.g. Periodicity is 1/4th,  8 pole machine is there, how ever if we have developed model for 2 poles only so Does flux will give me output for complete model of 8 poles or only it will give for modeled geometry of 2 Pole?

then if it is generating 5.3V DC , 2Amps then if we have to consider periodicity output then DC vtg = 5.3*4=21.2 & Amps 2*4 =8 so if I have to make it 14V DC constant then DO I need to adjust my load like to get DC Vtg= 14/4=3.5V so in full model it will be 14V DC, Please suggest

asoualmi

HI,

In the case of the periodicity (symmetry) it depends on which part you do your computation.

• If you compute on the part represented of the motor that means it is necessary to multiply by the periodicity. For example, when you compute the iron losses on stator, in this case you need to multiply bye the periodicity.
• If you compute on the mechanical sets, you don’t need to multiply by the periodicity.
• If you compute on the electrical circuit, in this case also you don’t need to multiply by the periodicity.

 Best regards.

Dattu B. Pawar

Abdessamed said:

HI,

In the case of the periodicity (symmetry) it depends on which part you do your computation.

• If you compute on the part represented of the motor that means it is necessary to multiply by the periodicity. For example, when you compute the iron losses on stator, in this case you need to multiply bye the periodicity.
• If you compute on the mechanical sets, you don’t need to multiply by the periodicity.
• If you compute on the electrical circuit, in this case also you don’t need to multiply by the periodicity.

 Best regards.

Thanks for your reply Abdesssamed, Could you please clarify point no. 1 in more broader way, wrt the point I mentioned in my questions I am unable to link both

asoualmi

Dattu B. Pawar said:

Thanks for your reply Abdesssamed, Could you please clarify point no. 1 in more broader way, wrt the point I mentioned in my questions I am unable to link both

Hi,

You are welcome.

For the point number one for example you want to compute the Joule losses on the magnets. You create a sensor and you select the face (volume) region correspond to the magnet. This means that you will compute just on the face(volume) regions that you have select. For this reason, you need to multiply by the periodicity.

 

Best regards.

Dattu B. Pawar

Abdessamed said:

Hi,

You are welcome.

For the point number one for example you want to compute the Joule losses on the magnets. You create a sensor and you select the face (volume) region correspond to the magnet. This means that you will compute just on the face(volume) regions that you have select. For this reason, you need to multiply by the periodicity.

 

Best regards.

okay, still I am not convinced,

Let's Discuss our case here, We are simulating Rotating Electrical  Synchronous Machine- Flywheel AC Generator where we need to compute the rectified DC Current at Constant Voltage of 14V DC, for this we have built 1/6th periodic model with 2 poles & same way 2 Poles of winding as well for these two conductors we have put 1/12th means each coil resistance for individual so basically 1/6th model simulation, in this case it should generated 2.33V vtg so we can achieve 2.33*6 =14V DC Constant, So when our model will generate 2.33V output constant then only I will measure Output DC Current, & whatever will be output DC Current should it be like e.g. it's generating 2 amps then 2*6=12 amps I need to consider or how, please guide it further on this point, circuit I have attached for clarity

Dattu B. Pawar

Is here anyone who can guide it on further please?

 

asoualmi

Dattu B. Pawar said:

okay, still I am not convinced,

Let's Discuss our case here, We are simulating Rotating Electrical  Synchronous Machine- Flywheel AC Generator where we need to compute the rectified DC Current at Constant Voltage of 14V DC, for this we have built 1/6th periodic model with 2 poles & same way 2 Poles of winding as well for these two conductors we have put 1/12th means each coil resistance for individual so basically 1/6th model simulation, in this case it should generated 2.33V vtg so we can achieve 2.33*6 =14V DC Constant, So when our model will generate 2.33V output constant then only I will measure Output DC Current, & whatever will be output DC Current should it be like e.g. it's generating 2 amps then 2*6=12 amps I need to consider or how, please guide it further on this point, circuit I have attached for clarity

Hi,

It is not clear for why in the circuit you divide the value of the resistance. As I said in my previous response, when you use a circuit you compute for the whole motor. This means that the value of the resistance in the coils are the phase resistance.

What  is the value that you put in the resistance in series and parallel with the conductor?

Can you share the Flux model.

Best regards.  

Dattu B. Pawar

Abdessamed said:

Hi,

It is not clear for why in the circuit you divide the value of the resistance. As I said in my previous response, when you use a circuit you compute for the whole motor. This means that the value of the resistance in the coils are the phase resistance.

What  is the value that you put in the resistance in series and parallel with the conductor?

Can you share the Flux model.

Best regards.  

Thanks Abdesssamed for reverting,

for your first point,

So do you mean to say if I put e.g. if our complete phase resistance is XX ohm then If I use XX/2 for 1st conductor & XX/2 for another conductor then whatever result output we will get, will be for complete model So I don't need to multiply by periodicity?

for your second point-

Please ignore for the series(1E-6ohm) & parallel(1E6ohm) resistances , Series R is for AC Current & parallel is for verifying Coil vtg additional crossverfication to direct measurement from Coil conductors, however being infinite R in parallel & Almost ) R in series will not impact the functionality or output.

 

Just please clarify first point so like if we will take.

 

Thanks.

SimonGuicheteau

As Abdessamed wrote, any computation like the voltage or current is done on the circuit so it will be for the whole device.