Fried cap in charger while driving -- thoughts on why?
Posted: Wed Feb 11, 2009 2:35 am
Ok - question time for current or former CF electric owners, or anyone who knows something about them...
I have a Zivan NG-3 charger sitting in between the two front seats. I use that charger for the obvious purpose - to charge the traction battery pack. So far, it has worked just fine.
While driving my CF Electric (aka The Griffon) today, everything seemed to be running ok, but I started to sense an alarming smell of something plastic getting TOO HOT! I looked down at the controller (I have the "engine cover" off, but the controller cover on), but didn't see any smoke. I then happened to notice something moving around the charger, and a second look revealed white smoke issuing from one of the vent fan openings. Note that the charger was not plugged in to AC at this point (I was driving on the road), but the dc output was connected into the 216V system through the SIM as one would expect.
Smoke issuing from any part of your EV (save tires when drag racing) is alarming, and it is especially so when you are travelling down a street and the item smoking is right next to you inside the passenger compartment. Luckily, I was travelling down a a straight section of street, and there is a quick disconnect on the DC output of the charger. I reached down and grabbed the connector and pulled it free, isolating the charger from the 216V system. The rest of the short drive proceeded uneventfully.
It's very possible I always disconnected (isolated) the Zivan charger when driving the van previously. I've only really been driving it for a few days; the previous trips were just "round the block" test drives.
When I got home, I disassembled the Zivan charger and found the smoked component is (or was?) a 100 uF 450V electrolytic capacitor which parallels the DC output.
This is sort of what I expected to find, although I can't see any reason for it other than sudden internal failure of that capacitor -- possible, but unlikely. It would be more likely to fail when the charger has been running, heated up, and finishing the charge at it's highest output voltage (~ 320 V).
But wait... what if a high voltage ripple coming out of the battery side of the traction controller caused an overload of AC flowing through the capacitor?
At first, I'd think the batteries would "stiffen" the 216V system to where there wouldn't be much ripple from the switching of the controller. But maybe in this case, they don't. Maybe the ripple frequency is too high, or...???
Has anyone had a problem like this before? Any ideas?
I'm concerned something may be wrong inside my traction controller (Lucas Mk 4A). I don't want it to fry my DC/DC converter, which is currently working very nicely. The controller does make more noise than I'd expect -- it sounds like there's actually something in there vibrating, especially at low power (crawling along at low speed). I wouldn't expect that from a electronic controller (does anyone know what frequency these controllers operate at?).
I have not had the time to remove the traction controller cover yet for an inspection.
I have a smaller variac-based charger that I can use in place of the Zivan for now.
Any help on this would be greatly appreciated.
- John
I have a Zivan NG-3 charger sitting in between the two front seats. I use that charger for the obvious purpose - to charge the traction battery pack. So far, it has worked just fine.
While driving my CF Electric (aka The Griffon) today, everything seemed to be running ok, but I started to sense an alarming smell of something plastic getting TOO HOT! I looked down at the controller (I have the "engine cover" off, but the controller cover on), but didn't see any smoke. I then happened to notice something moving around the charger, and a second look revealed white smoke issuing from one of the vent fan openings. Note that the charger was not plugged in to AC at this point (I was driving on the road), but the dc output was connected into the 216V system through the SIM as one would expect.
Smoke issuing from any part of your EV (save tires when drag racing) is alarming, and it is especially so when you are travelling down a street and the item smoking is right next to you inside the passenger compartment. Luckily, I was travelling down a a straight section of street, and there is a quick disconnect on the DC output of the charger. I reached down and grabbed the connector and pulled it free, isolating the charger from the 216V system. The rest of the short drive proceeded uneventfully.
It's very possible I always disconnected (isolated) the Zivan charger when driving the van previously. I've only really been driving it for a few days; the previous trips were just "round the block" test drives.
When I got home, I disassembled the Zivan charger and found the smoked component is (or was?) a 100 uF 450V electrolytic capacitor which parallels the DC output.
This is sort of what I expected to find, although I can't see any reason for it other than sudden internal failure of that capacitor -- possible, but unlikely. It would be more likely to fail when the charger has been running, heated up, and finishing the charge at it's highest output voltage (~ 320 V).
But wait... what if a high voltage ripple coming out of the battery side of the traction controller caused an overload of AC flowing through the capacitor?
At first, I'd think the batteries would "stiffen" the 216V system to where there wouldn't be much ripple from the switching of the controller. But maybe in this case, they don't. Maybe the ripple frequency is too high, or...???
Has anyone had a problem like this before? Any ideas?
I'm concerned something may be wrong inside my traction controller (Lucas Mk 4A). I don't want it to fry my DC/DC converter, which is currently working very nicely. The controller does make more noise than I'd expect -- it sounds like there's actually something in there vibrating, especially at low power (crawling along at low speed). I wouldn't expect that from a electronic controller (does anyone know what frequency these controllers operate at?).
I have not had the time to remove the traction controller cover yet for an inspection.
I have a smaller variac-based charger that I can use in place of the Zivan for now.
Any help on this would be greatly appreciated.
- John