rkosiorek
100 kW
after DC rectification and a couple of filter caps that 110VAC RMS becomes 110 * 1.414 = 156V. more than enough to charge that 120Vdc pack.
rick
rick
Knuckles said:5) Ecrazyman and I do have a PROBLEM, neither of us have brushless motors that can handle 72V nominal and 50-amps!!! I have no way to hard test this proposed 50-amp controller! So we ask for help from this forum. If he build it will you guys kick sh*t out of it?
-B
drewjet said:Knuckles said:5) Ecrazyman and I do have a PROBLEM, neither of us have brushless motors that can handle 72V nominal and 50-amps!!! I have no way to hard test this proposed 50-amp controller! So we ask for help from this forum. If he build it will you guys kick sh*t out of it?
-B
I am pushing 75 volts and 150 amps in my motorcycle.
tron said:What are you guys using for batteries? I don't see to many 72 volt battery packs except for SLA in series. What about modifiying e-crazyman's 48 volt 600 watt system with better fets and a lower cutoff. From a marketing standpoint wouldn't this be better for him to sell more units. Just my thoughts on this one. If most people are aiming for LifePO4 batteries, there are no practical systems yet that have good BMS over 48 volts. If he makes better 48 volt systems he can sell to a wider group of people and make more units at a lower price. Until he can redesing the PC board on the 72 volt to accept a variable cutoff that would go from 20 volts to 60 volts he won't get the 48 volt crowd. Help me if I'm missing something.
Hey Knuckles, I like what your doing here!
fechter said:Excellent. I'll take a good look at it when it arrives.
I'd recommend holding off on any board changes until we decide on a few more things. A new layout will cost money and take time. Let's try to get it right in fewer passes.
I don't think we should go overboard on the features too. Keep it simple and cheap, but bulletproof.
The BMC / Puma problem might be a bit tougher for me to test. I have one that's not mounted on anything yet, so I can bench test it, but not under full load.
We might need to send one of those over to Jozzer or Mark at Team Hybrid and see if he can blow it up. He's got a pretty big pile of smoked controllers over there from what I've heard.
Knuckles said:We will immediately start on a 72V 50-amp controller with 4110 fets. Is 59V fixed low V cut-off OK with everyone?
We hope to here Fechter’s feedback before we tell the factory to make these killer 50-amp units.
We plan on using the same size case (heat sink).
5) Ecrazyman and I do have a PROBLEM, neither of us have brushless motors that can handle 72V nominal and 50-amps!!! I have no way to hard test this proposed 50-amp controller! So we ask for help from this forum. If he build it will you guys kick sh*t out of it?
I am pushing 75 volts and 150 amps in my motorcycle.
And Y only 75V? Wouldn't 200V+ be better?
drewjet said:A Mars Brushless motor and 216 lithium cells
lazarus2405 said:Those are the best option for FETs above 100v. If you were to have controllers made to regularly operate above 110v, those are what you'd use. The drawback to those is that their On resistance is three times that of the 4110s. They need more cooling, and can handle less current than IRFB4110s. However, if you want to run those higher voltages, you have no choice.
Knuckles said:lazarus2405 wrote "That might be too high for folks using 66v a123 setups, who need a LVC of 54v."
Well I don't consider 10 a123 cells a true 36V pack. I consider 12 a123s a 36V pack. 10 a123's is a 33V pack (more like 30V IMO).
So I think 24 a123'a are needed to make a true 72V pack (and thus mate in p to a 60 cell NiMH pack)
This is significant and I welcome debate on this issue.
-B
lazarus2405 said:Knuckles said:lazarus2405 wrote "That might be too high for folks using 66v a123 setups, who need a LVC of 54v."
Well I don't consider 10 a123 cells a true 36V pack. I consider 12 a123s a 36V pack. 10 a123's is a 33V pack (more like 30V IMO).
So I think 24 a123'a are needed to make a true 72V pack (and thus mate in p to a 60 cell NiMH pack)
This is significant and I welcome debate on this issue.
-B
Most folks here don't use a123s in 24s; they use 20s for a 66v setup because that is how they come in the pack, spot-welded in a 10s configuration. Folks who don't want to completely rebuild their packs run them like that. It's too high of a voltage for a 48a controller, so they have to use a 72v unit. However, they'd loose a lot of capacity if it cut out early.
The real solution is the pot to adjust the LVC. We know that that's in the works. However, in the mean time, perhaps it would be wise to find out how to disable the LVC in those controllers, so a123-users can run without it in the mean time.