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Effect of Dynamic Advanced Active Clamping of 1SP0335 Gate drivers

Posted by: TK Kim on

Datasheets of 1SP0335 gate driver series introduce Dynamic Advanced Active Clamping(DA^2C) to suppress High Voltage during IGBT switching events.

I ask you to answer these questions about the 1SP0335 gate driver DAAC function.

1. Does DAAC function perfectly control (or cut away) high voltage over threshold voltage of each gate driver model?

--> whether the voltage on the switch(in turning off operation) is suppressed to be under the maximum available IGBT DC voltage (in case of 1SP0335-45 and 4.5kV IGBT pair or 1SP0335-65 and 6.5kV IGBT pair)

2. If RC or RDC snubbers are attached to IGBT, is there any problem with the DAAC function working correctly?

--> The existence of interaction between snubbers and gate driver DAAC function and whether the interaction interrupts DAAC function working

 

Thanks

回應

Submitted by PI-IWH on 09/29/2022

Dear Kim

thanks for the question 

here are feedback 

1, In general, DAAC has very good performance with 1SP0335 to protect IGBT from being destroying from excessive over voltage during turn off. 

it means, for a 4500V IGBT, if the maximum switching DC link value is 3000V, then the maximum Vce over voltage will be below 4500V,

the actual value will depends on stray inductance in commutation loop, turn off resistance, IGBT type, etc.

 

2, the DAAC starts to work as long as the Vce over voltage higher than a designed threshold Vce value of gate driver.

if there is strong oscillation on Vce by adding snubbers, and the peak value of the oscillation is higher the the Vce threshold value, it will lead to repeatedly DAAC actions. 

the gate driver will just do its job. However, the excessive DAAC is a condition should be avoid, since TVS diode on board will be heated up in a short time.

 

3, to have better view of DAAC, following points should be clarified 

the DC-link voltage value of "switching operation" means, IGBT will have turn-on and turn-off activities under this DC link value 

the DC-link voltage value of "Off state" means, the IGBT will stay at OFF states , please refer to Note 11 of datasheet of 1SP0335

 

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