brushless motor won't re-start - IR2110 control IC w/charge pump

[EPL803]

Hello, I use IR2110 to control power mosfet to power a three-phase brushless motor. I have to run the engine for a start. I mounted a charge pump that provides a voltage of 30V to VB but every time the PWM stop the engine does not start. VCC = + 15 = Vmot= + 24 PWM= 15 Khz
Every time I turn on the circuit the engine will not start: I lightly touch the tree to start working.
Can anyone help? thanks Luciano

 

[shaiko]

I assume your motor is sensorless?
What algorithm are you using to identify the rotor position?

 

[EPL803]

Thank you for your immediate response,
I use UCC3626. My engine has Hall sensors 120 °, two quadrant.
I believe that the problem is the management of the IR2110 in HO out that despite the bootstrap capacitor and a charge pump system, made with a 7 kHz oscillator, does not change status than its LIN. After turning on the circuit by increasing the voltage PWM you see out I always high and just moving the motor shaft that starts regularly. The current consumption is minimal and it seems to run very well. thanks Luciano

 

[FvM]

After turning on the circuit by increasing the voltage PWM you see out I always high and just moving the motor shaft that starts regularly.

We actually don't "see" anything as long as you don't post the circuit and waveforms.

 

[EPL803]

Hello, to start my testing I used the UCC3626 circuit application information Texas. I tried small changes but without result. I can not get to work HO out of IR2110.
I tried to drive the mosfet with MAX4427 and the motor can stop and start without problems. But I would like to understand how to work with IR2110.
Thanks for your time Luciano

 

[EPL803]

Hello, I finally solved the problem.
is very important to maintain the voltage VB and for this we need a pump charg I made with a frequency of about 8 kHz. When the power to give way to VB to bring the right tension I had to delay the start of the UCC3626 using a trigger smit 4093. For a second there remain high Coast of UCC3626 after which everything is ready ...
was very useful reading vs Forum and I was able to learn many things that led me to get the result. thanks Luciano

 

[EPL803]

https://obrazki.elektroda.pl/2239920300_1426074051.jpg
This is my project

 

[EPL803]

These are the waveforms: 1) Vb, 2) Vs, 3) to gate Hout.
The two images relate with engine ON and engine OFF.
When the engine is off you can better see the difference between VS and VB where Vb thanks to Charge Pump is polarized so that it can work in a continuous manner.
But now I formulate my question: the waveform obtained is correct in your opinion?
Should I try to clean again?
thanks Luciano