Ideas for Designing 3 Phase Power Stage For BLDC/ACIM Motor

Thread Starter

ashkarmalik

Joined Jul 1, 2012
75
I have recently started working on 5Kw BLDC Motor Controller That can be used as Either For brushed 5Kw PMDC Motor or BLDC Or ACIM.
Below is my Priliminary Power Stage ,Kindly Provide your Valuable Feedback.
Mosfet - IRFP4868
Vdss=300V
Id @ 25c= 70A
Gate Drivers- IR2110
Source-Drain@ 2A/2A
 

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Thread Starter

ashkarmalik

Joined Jul 1, 2012
75
The BLDC/DC servo drives that I use are settable from 120° commutation to 60° for DC brushed motors.
Max.
Hey Max, That is what I feel like doing in this drive.
And Do you know what Should I implement to Step down drives voltage ie.200vdc to 12v-5v-3.3v?
 

Thread Starter

ashkarmalik

Joined Jul 1, 2012
75
I am Little lost on selecting the Boot strap capacitor. Should I use Ceramic 0.47uF/300v Or Ceramic 0.47uF/25v When Drivinf the IR2110 With VDC=200V ?
 

Robin66

Joined Jan 5, 2016
252
the bootscrap caps (C1 & C5 for example) are only charged to 12V-(diode drop) in this schematic, so 25V would be plenty. You need to ensure the diode (D5) can handle the reverse bias of Vcc tho (I'm guessing Vcc is 200V)
 

Thread Starter

ashkarmalik

Joined Jul 1, 2012
75
the bootscrap caps (C1 & C5 for example) are only charged to 12V-(diode drop) in this schematic, so 25V would be plenty. You need to ensure the diode (D5) can handle the reverse bias of Vcc tho (I'm guessing Vcc is 200V)
Alright, Thanks for the Clearification. I was confused about the Bootstrap voltages.
And for the Bootstrap Diode I am Using STTH3R04S

IF(AV) 3 A
VRRM 400 V
Tj (max) 175 °C
VF (typ) 0.9 V
trr (typ) 18 ns

I was searching for DC-Link Capacitor So I got This Link from Avnet - LINK
So According to the note

For low power AC-DC converters with no PFC stage, minimum capacitance is normally set by the allowed mains ripple voltage on the DC-link. This gives a capacitance value of approximately 2 µF/watt for a universal mains input supply. For higher power AC-DC converters with PFC, the value is set by ‘hold-up’ or ‘ride-through’ time on input power loss and a much lower capacitance is possible with energy stored at high voltage, values of less than 1 µF/watt being normal.

Does that mean if I am designing a 3 Kw Load then I would require 3000uF Cap ?

@MaxHeadRoom Thanks for this link
I have Just a Small Query- How Should The IDDO Value calculated?
 
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Thread Starter

ashkarmalik

Joined Jul 1, 2012
75
Wow... I was going to talk you out of it, since it's an MCU that most people are unfamiliar with, but then I saw it's datasheet and it looks like a rather powerful beast.
I know its a bit overkill for this project but you know what they say "If we can put it on the board then we will definitely put it".
What attracted me are-
12-Bit Analog-to-DigitalConverter - 3.46MSPS
16 PWMChannelsTotal(8 HRPWM-Capable)
and Plenty of Advanced hardware support modules for future upgradation as well.
 

cmartinez

Joined Jan 17, 2007
6,646
The one thing that bothers me is the device's packaging. I would prefer one that could be inserted in a socket instead of being forced to soldering it to the PCB.
 

Thread Starter

ashkarmalik

Joined Jul 1, 2012
75
The one thing that bothers me is the device's packaging. I would prefer one that could be inserted in a socket instead of being forced to soldering it to the PCB.
That is definitely a downside with these advanced controllers but I have to stuck with the 100 Pin LQFP Package, I have already got them.
Now there is some verification that I need to do.
1) Value Of DC-link Capacitor
2) During Running a Servo Motor with High Response rate what Protection Circuits need to be implemented at the Power Stage.
 

Uilnaydar

Joined Jan 30, 2008
118
My suggestion is: stop pressing that bloody Capital lock key at random.
Heh... got a kid at work that does this. Drives me nuts!!! You handled it much better than I did. I brought up a cheese grater and Tabasco sauce the next time he sends one like that. Love those visits to HR.
 
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