I'm confused on IR21362 IGBT Driver For 3PHASE ACIM operation

[medik]

Hi,
I have been studying different articles especially App note AN843 from Microchip on controlling 3phase AC induction motor. I understand the math behind the 120° phase angle between phase.
 My greatest confusion is how to implement the negative half-cycle of a phase. In single phase, the other half cycle is done by changing direction of switching via code after 10ms for 50Hz output.
Does it mean that IR21362 handles the direction? if yes, how?

it is unfortunate  that there's no simulation model for this driver in Proteus. I would appreciate your clarifications.

Rephrased:

Hello,

Please, I would like  to know how the IR21362 chip handles the 3 phase pwm signals from microcontroller to determine the positive and negative half-cycles of each phase. I have pulled my hairs trying to figure that from the Microchip AN843 app note. I understand clearly from code, how the positive half-cycle of each phase is generated. But the negative half-cycle is not covered in code, does the IR21362 automatically handles that?



Those that have used the 3phase IGBT driver chip should please clear my doubts. Thanks.

[sohel]

you can use STGIPL14K60 without driver. or 6 TLP250.

I have done with dsPIC30F2010
https://youtu.be/dapsrU5SLBo?list=PL1tqVlWKcjR2WCI4TAiqzlILdiSiDfoeO

[medik]

Thanks Sohel for your reply. Please I am completely new to 3phase generation unlike single phase H-bridge, is it possible to guide me with a diagram? or PWM pattern for the mosfet using TLP250.

[sohel]

Dear, I think you should buy Microchip dev tools regarding this projects. or see some of them which topology they use.  start with AN967

[kreutz]

Take a look at table # 6 on the Microchip's AN. It seems they coded the complete AC cycle for each phase, in the pwm table, with 1/2 cycle positive offset already on it, so max pwm  value is positive half peak  and zero pwm is negative peak, so there is no need to add any additional state commutation logic in the power stage.

[medik]

Dear, I think you should buy Microchip dev tools regarding this projects. or see some of them which topology they use.  start with AN967

Noted, I will look into more app notes on the subject.

Take a look at table # 6 on the Microchip's AN. It seems they coded the complete AC cycle for each phase, in the pwm table, with 1/2 cycle positive offset already on it, so max pwm  value is positive half peak  and zero pwm is negative peak, so there is no need to add any additional state commutation logic in the power stage.

That is a wonderful insight. Highly appreciated.I will examine closely as you have interpreted.