Paul & Sabrina's cheap DIY 144v motor controller

[drbobwoolery]

The possibility that this sort of interference would mess up the function of the low level board has me thinking of separate boxes for the low level and high level parts of the device.
Lossy ferrite cores threaded over leads are popular at low power levels for surpressing hash. For this, we need a 1 inch hole to allow clearance on 4-0 insulated welding cable, and the toroids used for transformer cores will not do. I'll try to search out some large RFI lossy toroids. This outfit has some with .90 ID, but the permeability can be from 40 to 10,000. For this RFI surpression application, I'm not sure what to try.
Ferrite Toroidal Cores : CWS ByteMark, largest supplier of toroids, ferrite cores, iron powder cores, MPP cores and RF cores

Slipping one or more of these on each power lead of the controller should help the external RFI issue, subject to fines from the FCC if not kept appropriately down.

bob

[asyx]

hi everybody! here is a better diode to use on controller

DSEI120-06A

[jackbauer]

MITSUBISHI RM300CA-9W FAST RECOVERY DIODE LOT OF 2 on eBay (end time 15-Oct-09 14:53:21 BST)
Mine is bigger than yours
1200amps muhahahahaha!

[asyx]

on datasheet looks just 300A/450V and is not so fast.but it is ok

[jackbauer]

yeah each module has 2 x 300amp diodes so i hope will give 1200amps total when in parallel. I agree its a bit slow on recovery but should still be ok at 16khz. Besides i don't want it to have a very harsh recovery.

[MPaulHolmes]

Are the dedicated diodes better than the intrinsic diodes of the IGBTs? I guess they were cheaper, so maybe it's better to use them. Hey I mailed the LEM!

[asyx]

Jackbauer as i know(maybe wrong) in any datasheet is indicated the total power of the 2 diode.so each diode have 150A,total 300A not 600A

[jackbauer]

thanks paul i owe you one! I just spotted those diodes at the right price so decided to give em a try. May work , may not. I'm not sure yet as to whether i'll use the two igbts as switches or one as a switch and one as freewheel. Using one switch has the advantage of no current sharing problems. asyx you may well be correct i'm not sure myself. Two of these babies would be great but a little pricey:
IXYS Single fast diode module 500A 600V (MEO500-06DA) on eBay (end time 04-Nov-09 10:50:19 GMT)

[jackbauer]

Guys i loaded the new firmware with the botloader built in and the orange led is flashing rapidly is that normal?

[adamj12b]

If you dont have the LEM hooked up or dont have 2.5V on the current input, you will get an error and the LED wont stop blinking. Also if the throttle is not 0 on start up the LED will blink until you bring the throttle to 0 and then it will go solid.

-Adam