High side IGBT for negative voltages

Discussion in 'The Projects Forum' started by sriniketh, Sep 29, 2015.

  1. sriniketh

    Thread Starter New Member

    Jul 7, 2015
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    0
    I am trying to design a circuit using IGBT whose collector is connected to 0V (machine ground) and emitter is connected to -800VDC (negative). I am using IRS2113 high side low side driver in half bridge circuit. How shall i connect the common pin of the IRS2113 whether to 0V or -800VDC . Kindly suggest. how can i isolate the control and power side .?
    I haave attached the schematic of the circuit drawn in KiCAD.



    circuit.jpg
     
  2. RamaD

    Active Member

    Dec 4, 2009
    254
    33
    These bootstrap gate drivers are designed for connection to the low side IGBT's emitter, or MOSFET's source, in this case -800VDC. The logic supply ground has to be within +/-5V of COM. The inputs to the MGD (microcontroller) also should be referenced to this only. BTW, IRS2113 is for use upto 600V only and some other component needs to be selected.
     
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  3. Bordodynov

    Active Member

    May 20, 2015
    637
    188
    We'll have to make also galvanically isolated power supply for the driver. Negative pin connected to the source of -800V. Manage the driver will have through optocoupler.
     
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  4. sriniketh

    Thread Starter New Member

    Jul 7, 2015
    28
    0
    Thank you for the reply, Is it possible to design the high side circuit just by using isolated gate drivers? Yes i am aware about the voltage offset constraints about the gate driver. But before that i am confused about the reference voltage for the logic section and the gate driver section. Can you clarify the same ?
     
  5. Bordodynov

    Active Member

    May 20, 2015
    637
    188
    Using isolation using optocoupler or transformer can be controlled by the upper and lower gates simple identical drivers. You only need to make two isolated voltage source. Wiring for the upper and lower transistors are identical. And there is no need for complicated driver upper and lower gates.

    DrajverGate.png
     
    Last edited: Oct 5, 2015
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