Question1:

In the functional reference manual of iMotion it is mentioned in the Motor control section that the DC bus voltage sampling is done every PWM cycle.

Later on the PFC section, it is mentioned that the DC bus voltage is again sampled depending on the setting of the base rate for PFC current control.

If the PWM frequency of the motor control side does not match with the PFC side, does this mean that the DC bus voltage would be sampled by two independent tasks?

Question 2:

In the datasheet a gain error of 0.5% and offset error of 8 mV is mentioned on the ADC section. Does this apply also for the VDC sensing?

Hi there,

I have a question on how the VadcRef is generated for the IMC100 series. Is it the same as Vdd which is nominally set to 3.3 V or do you have a better calibrated voltage source for the Vadc ref? I could not find details in the functional reference manual.

Hi,

Im having some problem using the script to know if the motor has stopped.

The logic of the script is:

- Use zero braking vector to stop.

- When SpdRef is 0 i activate a pin.

The problem is that the information of the motor stop is very delayed.

As you can see in the graph (with sample rate of 100 samples/second), the motor takes about 250 ms to go from 600RPM to 0RPM. 

The total time since I order to stop till i get the signal from the imc102t pin is about 500ms.

I have debounce of 10ms in the microcontroller, when i receive the signal that the motor has stopped it takes less that 20 ms to activate the lock. The image bellow shows the activation of the imc102T pin (yellow) and lock activation (blue). The imc102t pin is isolated with a optoacoplador.

But, 500-250-20 = 230 ms, because of this time, after the motor stops the gate falls down a bit and then it locks.

To see if it was the script fault i used the RunTimeCounter, i used it to measure the time it takes since the zero braking activation till the pin activation, and it would take less than 10ms. 

After that i also used the RunTimeCounter to count the time between the stop order and the pin activation, the result was 474 ms. 

The problem must be in the script.

The problem can be the in the script execution being delayed because of the motor control?

If it was delayed, it would affect the RunTimeCounter?

I need some help with this problem.

Attached is the MCEWizard configuration file.

Thanks,

Paulo

Hi,

I'm having trouble figuring out if the PFC is working properly in my controller. So i have some questions to ask:

1 - Is there a way to know if its working properly using MCEDesigner? Or i need to check input Voltage/Current to see the power factor?

2 - Do i need to change gains based on load and motor?

3 - What variables do i need to change in order to get the best results with PFC?

Best Regards,

Paulo

Hello there,

I am trying to understand the sample rate of the DC link voltage in IMC102T-F048. I can see in the functional reference manual for IMC100 that this probably depends on the configuration of the base rate. Assuming we choose the ratio of 1:1 between PWM and base rate, would all ADC inputs be sampled once per PWM cycle? I was just wondering if there is a possibilty to undersample the Vdc input.