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zain
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I bought the following board mentioned in title. I have all the exclusive information. I want to know how the board regulates the voltage in BOOST mode? I want specific answer to it.

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Abhilash_P
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Hi,

 

     For operating the converter safely, the HV supply, LV supply and loads has to be in the range as shown in the below image. Also in the boost mode proper power levels has to be maintained and the correct precharge circuit  has to be designed . The converter has not been designed to operate in voltage range other than mentioned in the below image,

Abhilash_P_0-1655469362485.png

 

You can go through this link for redesigning the circuit. It is potentially possible, adapting the firmware in accordance. However, I would not recommend that approach. It will be more cost consuming redesigning the series inductor, the transformer, the switches (Rds(ON)) and the sensing circuitry for the different specifications. 

The current limits and the protection features has to be properly set in the GUI before using it in the boost mode. 

One more reason being, during the start-up the converter takes more current than in steady state, even at that light load as it  also needs to charge up the HV capacitor from the starting voltage up to the 400V regulation. During the start-up in some conditions the converter feeds back some energy from the HV side, and with LV supplies without sinking capability might cause the voltage to raise beyond the LV upper limit (approx. 58 V) of the converter and might damage the converter if proper protection features are not enabled. 

 

 

Regards,
Abhilash P

 

 

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Abhilash_P
Moderator
Moderator 25 likes received 250 replies posted 250 sign-ins
Moderator

Hi,

 

    Thank you for posting on the Infineon Community. 

 

To understand about the modulation scheme of PSFB in boost mode, please refer the following IEEE paper from infineon, 

" Modulation Scheme for the Bidirectional Operation of the Phase-Shift Full-Bridge Power Converter.
   Manuel Escudero , David Meneses, Noel Rodriguez , and Diego Pedro Morales"

 

Regards,
Abhilash P

zain
Level 1
5 sign-ins First reply posted First like given
Level 1

Thank you Abhilash for the reply. I have downloaded the paper. I am designing high power BOOST converter only, please tell me if you recommend this design or can suggest some other one.

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Abhilash_P
Moderator
Moderator 25 likes received 250 replies posted 250 sign-ins
Moderator

Hi Zain,

 

      Can you please share your specifications?, I can suggest you accordingly. 

And also please do specify the reason for using bidirectional PSFB for your application. 

 

Regards,
Abhilash P

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zain
Level 1
5 sign-ins First reply posted First like given
Level 1

I am looking for 24VDC to 200VDC 2k5W to 3kW. And i have read the paper, sadly i have this confusion as in how to regulate voltage in BOOST, by means of boost duty or pwm duty? actually i was testing the prototype and damaged it, now i am looking for answers.

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Abhilash_P
Moderator
Moderator 25 likes received 250 replies posted 250 sign-ins
Moderator

Hi,

 

     For operating the converter safely, the HV supply, LV supply and loads has to be in the range as shown in the below image. Also in the boost mode proper power levels has to be maintained and the correct precharge circuit  has to be designed . The converter has not been designed to operate in voltage range other than mentioned in the below image,

Abhilash_P_0-1655469362485.png

 

You can go through this link for redesigning the circuit. It is potentially possible, adapting the firmware in accordance. However, I would not recommend that approach. It will be more cost consuming redesigning the series inductor, the transformer, the switches (Rds(ON)) and the sensing circuitry for the different specifications. 

The current limits and the protection features has to be properly set in the GUI before using it in the boost mode. 

One more reason being, during the start-up the converter takes more current than in steady state, even at that light load as it  also needs to charge up the HV capacitor from the starting voltage up to the 400V regulation. During the start-up in some conditions the converter feeds back some energy from the HV side, and with LV supplies without sinking capability might cause the voltage to raise beyond the LV upper limit (approx. 58 V) of the converter and might damage the converter if proper protection features are not enabled. 

 

 

Regards,
Abhilash P

 

 

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zain
Level 1
5 sign-ins First reply posted First like given
Level 1

I have turned on the converter several times before it got damaged, It was damaged while i was checking some thing on oscilloscope. HV bridge and gate driver got damaged possibly because of voltage overshoot in the HV bridge.

And please tell what is the regulation technique used in BOOST? And if there is some other BOOST board you can recommend from infineon?

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Abhilash_P
Moderator
Moderator 25 likes received 250 replies posted 250 sign-ins
Moderator

Hi,

 

      The bidirectional concept is patent pending but for basic understanding  you can refer the paper that was shared earlier. Basically it is regulated using boost duty. 

As far the EVK is concerned, unfortunately we do not have any other EVK's which fits your specification / application. 

 

Regards,
Abhilash P