Quantcast
Channel: Motor drivers forum - Recent Threads
Viewing all 21614 articles
Browse latest View live
↧

RE: DRV8320: Cannot get BLDC motor spinning due to Gate Drive Faults Read more forums - Followup

September 6, 2018, 4:22 pm
$
0
0
Thank you for being so responsive to all my questions Rick. Everything you said was spot on and did the trick. I will consider to use the DRV8323s instead now, as I can measure the current directly with it.

Removing the capacitor solved the gate drive issue, and the motor spun for a short time until faulting out again. I think this will be fixed with your resistor recommendation. I do not have low enough value resistors on hand to verify the "add a resistor from the low side FET source to the ground" fix, but I think that will do the trick. Thank you.
↧
Search

drv10983evm

September 6, 2018, 9:35 pm
$
0
0

Hi 

anyone can explain triac based ac controlled fan using drv10983.

↧
↧

DRV10983Q1EVM: speed command issue

August 7, 2018, 10:44 am
$
0
0

Part Number: DRV10983Q1EVM

Team, 

My customer is looking for help:

We have encountered a failure mode involving the DRV10983Q1EVM (evaluation board) and the DRV109XX EVM software and we wondered if any of your engineers could help us figure out the possible cause.

Currently, when a speed command is given over I2C to the evaluation board, the BLDC motor will immediately ramp up to max speed after crossing the Open loop to Closed loop threshold. Furthermore it will not respond to any subsequent speed commands given.

Through our debugging process, we have found out the following:

  1. The supply voltage VCC as read by the board is 11.8V when provided with 13V via power supply. 13V is read via multimeter on the VCC pin of the DRV10983Q1.
  2. The RPM calculated by the board is about 50% higher. For instance it reports 1800rpm for max speed when our motor is running at 1200rpm as confirmed via oscilloscope.
  3. If mechanical AVS is unchecked/disabled, then the board will respond normally to various I2C speed commands. However, the voltage and speed readings are still as seen in #1 and #2.

 Two different EVM boards have exhibited the same symptoms described above. For the previous 6 months, we had been manually setting the registers on the TI DRV109XX EVM software without encountering any issues. Then after making use of the configuration file, EEWRITE, and EEREFRESH features of the DRV109XX EVM software, we first noticed the abnormal behavior on both boards. The software version used was 3.2.2.0.

We have since updated to the latest software version of 3.3.4, but setting the registers manually does not fix the issue.

Are there any known issues that could cause this? If you need any additional information please let me know.

Thanks

Viktorija

↧

RE: DRV8308: evaluation board

September 7, 2018, 9:08 am
$
0
0
Hello Hong Sun,

Let me check with our EVM support team to see what is that latest revision we have in stock.
↧

RE: CCS/BOOSTXL-DRV8301: Reset Fault on DRV8301 by software

September 7, 2018, 9:25 am
$
0
0
Hello Uladzimir,

Let me check with my team to see how we resolved the issue from the previous post.
↧
↧

CCS/BOOSTXL-DRV8301: Reset Fault on DRV8301 by software

September 7, 2018, 6:50 am
$
0
0

Part Number: BOOSTXL-DRV8301

Tool/software: Code Composer Studio

There is an issue with LAUNCHXL-F28069M  + BOOSTXL-DRV8301 REVB
I intentionally cause short circuit to test protection, but then can't reset OCTW and FAULT flags with SPI command Control Register 1 : GATE_RESET. After power reset the flags are reset and I can drive the motor.
But we need to do it programmatically.

- Used firmware is motorware 1_01_00_18
- OCTW and FAULT gpios are not used, these gpios are configured used for USB serial port. (JP6 is open, JP7 is closed)
- VDD is 12V.
- OVC is triggered by shorting phases B & C
- BOOSTXL-DRV8301 is inserted in J1 socket of LAUNCHXL-F28069M

There is a related question, but still no answer. Seems triggering EN-GATE pin also doesn't help.

Could anyone help please?

↧

RE: DRV8870: driver Chip blow up

September 7, 2018, 9:48 am
$
0
0
Hi Steve,

Can you tell what seems to be the failure? Is the device hot when it fails? Does it pop, crack, or otherwise let out smoke?

Does it fail before detecting stall, or does it fail after detecting stall when it is in brake mode?

Are you able to repeat the failure and take scope shots of the VM and VREF voltage at the pins and the current through the motor?
↧

RE: DRV8870: driver Chip blow up

September 7, 2018, 12:11 pm
$
0
0
Hi James ,
It start getting hot and eventualy smoke up after i detect stall and immediatly put iT at break.
I have the impression this does not happen when I ramp down to zero and Then break.
So iT seems to happen when I break too fast .

I use a pi filter for the drivers supply voltage.
And wondering if immediat break from a 2-3A load situation can cause a large voltage Spike on VM which kills the driver ? On the other side, should the cap after the inductor prevent any spikes in VM.

Thx
↧
Search

RE: DRV8870: driver Chip blow up

September 7, 2018, 12:12 pm
$
0
0
So iT seems to happen Just after break mode
↧
↧

DRV8870: driver Chip blow up

September 7, 2018, 7:17 am
$
0
0

Part Number: DRV8870

We use the DRV8870 as motor driver at 24V 15kHz to drive a DC 24V motor. Vref = 5V ISEN = GND , VM  is connected trough a LC 15µH and 220uF to 24V

For some reason the driver blow up when we block the motor.

The firmware has a stall detection and put the motor in break (both Motor pins at 0V) after 1 second stalling.

Even while the chip have an aditional current and termal protection the chip blow up every time we stall the motor.

What can cause a failure of internal protection circuits in this chip? We already lowered input protection resitors to 10 Ohm.

Thank you

↧

RE: DRV91680 Programmer

September 7, 2018, 12:26 pm
$
0
0

Che,

I'm working with the MSP team to get you the documentation. Hopefully I'll have it ready to send on Monday.

Thanks,

Brian

↧

RE: drv10983evm

September 7, 2018, 2:36 pm
$
0
0
Deva,

DRV10983 is intended to drive a 3 phase BLDC. It is not for an AC motor.

Regards,
Brian
↧

RE: DRV8801: Reverse Current Reduction

September 7, 2018, 2:54 pm
$
0
0
Wang,

Do they test on an EVM or their board?
"the reverse current can go to -1.76A" Is it input current? Where do they measure the current?

This is high di/dt (1.76A under 1us; up and down) event.
1. The board highest voltage is 10V, if the current goes through a inductor, v=Ldi/dt; L could be lower than (10V/1.76) uH. So, it may not a load issue unless you have load short.
2. di/dt up and down If the FETs are short, it should be only one way.

To me, it seems you measure a capacitor's charge and discharge current or a layout issue. Please let me know your measurement point.
↧
↧

DRV8801: Reverse Current Reduction

September 7, 2018, 8:33 am
$
0
0

Part Number: DRV8801

Hi Team,

One of the customer has the reverse current issue, the reverse current can go to -1.76A which is a little high.

They are wondering:

1. What could be the reason of the high current? 

2. Is it possible to reduce the reverse current? If so, how to do it?

Could you please help to analysis and give some suggestions? Thank you!

Here is the waveform:

CH2: Current; CH3: OUT2 voltage; CH4: OUT1 voltage

The schematic is as follows: the brushed motor is powered by 4 cell battery and the PWM frequency is 16kHz

↧

RE: DRV10983: DRV10983_USB2ANY- Register writing error !!!

September 7, 2018, 2:58 pm
$
0
0
Hey Pratik,

The evm gui will give that error message as long as the board doesn't have the expected voltages on Vcc, Vreg, V3p3, V1p8, so let's focus on the board.

I want to eliminate the possibility that we are not measuring the voltages correctly or somehow there is a bench voltage supply issue.
It is very strange that for two evm's, there is unexpected voltage on Vreg, V3P3, and V1P8.

1) Can you please specify exactly what voltages you are seeing on Vreg, V3P3 and V1P8?
2) Make sure you are measuring the voltage accurately with the DMM by trying to measure Vcc at the EVM hook terminal and seeing if you see 24V.
3) Make sure the current limit on the voltage supply isn't too low and that the Voltage supply isn't stopping output when current consumption gets high.

Let me know what you find.

Sanmesh U.
↧
Search

DRV8308: behavior when switching position while moving

September 7, 2018, 3:00 pm
$
0
0

Part Number: DRV8308

Hello there,

I have a DRV8308 EVM which has the rev. a chip and its document stated the behavior when switching the direction while motor is moving:

"If the commanded direction is changed while the motor is moving, the device either brakes or allows the motor to
coast, depending on the state of the BRKMODE bit, until the motor stops. The stopped condition is determined
by measuring the period of the HALL_U signal; when the period exceeds 160 ms, typical operation resumes and
the motor starts spinning in the commanded direction. This prevents excessive current flow in the output stage if
the motor is reversed while running at speed."

The rev b version has only "If the commanded direction is changed while the motor is still spinning, this may cause excessive current flow in
the output stage."

in EVM board, my motor can rotate properly when I change direction by either giving a pwm duty cylce of 20% and flip the DIR  from the GUI provided by TI or stopping motor by set pwm duty cycle to 0, then 20% and then click DIR.

Now with my own development board, which has rev b. chip.   Motor might stuck which switching direction using the either one of the approach I chosen above.  if I helps the motor to move a little bit, then motor would start to rotate.   I don't know what is the problem and am wondering what is the behavior when DIR signal is toggled high to low or low to high: does DRV8308 simply reverse the commutation sequence based on the directional signal directly no matter if motor is rotated or not.  One more behavior is that when motor stuck, the LOCK signal is still set.

thanks,

Hong

↧

RE: DRV10983EVM: How to enter winding resistance of 0.31 Ohm? Where can I find an example for BLDC gear-pump with 2A current?

September 7, 2018, 3:09 pm
$
0
0

Hey Edelbert,

The Commutation Control Advance Angle section in the DRV10983 Datasheet discusses the definition and influences of the control advance time.

As shown in the figure above, we can summarize control advance time as the a parameter that determines when the voltage is applied to the phases. Essentially, we want the Phase current to be in phase (or line up) with the Phase BEMF voltage. If these waveforms are in phase, we know that the applied magnetic field from the coils matches with the physical rotation of the motor. For example, if the current 0A when the BEMF is 0V, we know that the rotor is the aligned to the coil (motor pole).

As a result, if the time is too high or too low, by a small amount, the motor won't be as efficient (more phase voltage and current required for same speed). Following the procedure in the tuning guide will help tune the parameter. If the time is too large, the motor will fail to spin at all because the magnetic fields will conflict with the position of the motor.

Glad to hear the calculated Kt has helped you.

Best,

-Cole

↧
↧

DRV10983EVM: How to enter winding resistance of 0.31 Ohm? Where can I find an example for BLDC gear-pump with 2A current?

September 7, 2018, 1:12 am
$
0
0

Part Number: DRV10983EVM

With Your help I got the Motor running.

Please can You give me some Information about the influence of Control Advance Time.

What will happen if the value is too low or too high?

With the rough calculations for "Kt" described in the Tuning Guide I got a value of 50mV/Hz.

This value proofed to be good during testing.

Thank You

Edelbert

↧

RE: drv10983evm

September 7, 2018, 9:05 pm
$
0
0

yes i am using bldc motor for fan. i need to control the mototor speed only using triac based ac regulator

↧

RE: drv10983evm explain this circuit

September 7, 2018, 11:09 pm
$
0
0
optocoupler input ac or dc, what about the transformer output voltage
↧
Viewing all 21614 articles
Browse latest View live
Search
<script src="https://jsc.adskeeper.com/r/s/rssing.com.1596347.js" async> </script>