CCS/TMDSHVBLPFCKIT: Vloop of BLPFC

user5081490

Part Number: TMDSHVBLPFCKIT
Other Parts Discussed in Thread: CONTROLSUITE

Tool/software: Code Composer Studio

When I use the Build3 to my BLPFC board 。

The output voltage reach to the 310V ，the TI program's PWM will shunt dowm 。

I think the output voltage is divided across three series resistors by 1M、1M and 22k，while the output voltage reach 310V ，this already over the VBUS_OVP_THRSHLD ((int32)((440.0/VBUS_FULL_RANGE)*4096*4096))

what can I do to solve this problem or what the TI do to solve this problem

the SCH is from controlSUITE\development_kits\BLPFC_v1.0\Hardware
the software is from controlSUITE\development_kits\BLPFC_v1.0

over 6 years ago

0 Shamim Choudhury over 6 years ago

TI__Genius 10995 points

310V should not activate OVP. As you can see from the BridgelessPFC-Settings.h file the OVP threshold voltage (for Vout) is set to 440V. Also Vout sense resistors are R13(1M), R14(1M) and R15(13k). This means VBUS_FULL_RANGE (corresponding to 3.3V at the ADC input) is about 510V. So the per unit Vout reading, when OVP is activated should be 440/510 = 0.863.
This kit is configured to output 400V. These settings are in BridgelessPFC-Settings.h and the related parameters are:

#define VBUS_RATED_VOLTS (400.0)
#define VBUS_OVP_THRSHLD ((int32)((440.0/VBUS_FULL_RANGE)*4096*4096))
#define VBUS_TARGET ((int32)((VBUS_RATED_VOLTS/VBUS_FULL_RANGE)*4096*4096))

Please review the User-Guide and run Build-1 and Build - 2 software to check the Vout reading using CCS RT Watch window. For example if your Vout is 310V then the per unit reading should be 310/510 = 0.607

Shamim