Contactor (Contactor Based PHEV)

EV200 contactor is what i and other also use rated for 200 amps con. and cheaper then others.. but not sure about the ones you refer to.

 

Contactor based PHEV is using the PHEV batteries to directly connect to the HV power line using contactors. The tyco contactor you mentioned are the contactor used to connect the PHEV battery to HV power line. Enginer is converter based and do not use contactors. The converter output connects directly to the HV power line. I believe Hymotion is also converter based. The 100amp and the 200amp you've mentioned are the contactor's rating. contactor based PHEV can yield higher mileage than converter based.

 

It s a big difference in between contacts ratings for AC and DC.
Usually contactors are defined for making/braking AC current connections with an ac coil whereas relays are for DC current handling.

 

I think one of the big differences is in contactor cycling. The early cal-cars type design used a PHEV battery with a voltage intentionally higher than the built in HEV battery, which it would dynamically connect and disconnect to the OEM battery via the contactor while driving to force the OEM BMS to "re-cal" and adjust the estimated battery SOC up. By doing this repeatedly you could keep the BMS estimated SOC high enough to force the system to use a lot more electric drive and enhance mileage significantly. In this arrangement, the contactor could easily be switching 100s of times per trip, and routinely breaking contact during significant current flow. Consequently they chose to go with a very robust contactor. Over time the system evolved from this "SOC drift" mode to "SOC spoofing", where you no longer have to yank the HV voltage high enough to trigger re-cal, you just maintain the voltage at a reasonable level and replace the SOC value on the CAN bus with a suitably high value to accomplish the same increased use of electric drive. In this arrangement, particularly if the PHEV battery voltage is similar to the HEV battery voltage its likely you'll be cycling the contactors much more infrequently, maybe only at startup and shutdown. So you could argue that a lesser contactor would be fine. On the other hand the contactor is really you primary piece of safety equipment, so maybe its not the best place to cut corners. I guess it depends on what sort of setup you are looking at and what your expected failure scenarios are.

 

you can do this with just 1 contactor!
then you connect the MIN from you add pack to the min of t he OEM
and the PLUS of you addpack to the prius side of the plus behind the prius contactor.
make sure you first start the prius let the prius close the oem contactors and then close yours.
this way you only need one expensif contactor


also when trhere is a problem you just shutdown the prius and the Addpack is disconnected from the OEM.

 

Sigh.... I realize I just joined this forum. I signed up because this forum post came into my email via a google alert. I'm a HEV and EV systems engineer, and a large part of my job is HV electrical architecture and control systems. I have done design engineering on many different light duty hybrid vehicles that are in the market, or are shortly coming to market, and there are probably very few engineers in North America that have spend as much time as I have on understanding the guts of the prius.

With respect to the above post: please do not do this foolishness. Sooner or later, you guys will have a welded contactor from an unintended short, and your whole car will go up in flames. And hopefully you didnt park it inside your attached garage that day. Connecting two different battery packs in parallel like this is an absolutely terrible idea, and is NOT safe, and I urge you guys to not even consider it. The problem with contactors opening under current is that you dont know how much current there was when that contactor opened. Your control system isnt faster enough to know this overcurrent value, and even if it was, what would you do with this information...In most systems we are now locking out battery operation if the contactors open under load in order to force the technician to replace the contactor. We are also implementing contactor weld checks to ensure that we know if a contactor is welded. We also design the system so that if one contactor welds, you still can remove HV from the system immediately using the other contactor, and then lock down the system for repair.

This is my two cents. Take it for what its worth.

 

The HEV Engineer makes a good point of contactor welds. Best to use a contactor in both positive and negative legs. If you are really worried you can use two pole contactors and electrically interlock the two contactors so that if one cpntactor welds the other contactor will be locked out. He also makes a good point of the event of getting a unintended short circuit which is why you need to install HRC fuses.

 

not sure if you did read it
but the add pack can be attached and stay there
only when the add battery pack is being recharged then its not

after years of contactor based DIY community prius builds on the internet i did not read about any prius go up in flames or a Ev200 contactor failing
and based on what i do, the prius contactors also double play in safety.

i also planned on using 2 contators but based on above info there is really no problem i think

i also can manual disconnect and have a add pack fuse 125 amps in place..

i also use temp sensors

and plan to connect a car alarm to the sensors relays.

 

Excuse me for being stupid on this but I just have to ask.

Why can't mechanical contactors be done away with by using solid state components? Is it because of the high current involved cannot be handled by solid state components? Or the price is too high? It seems all this "welding" could be avoided and the circuit could be better controlled.

PS: Just to let you know, I'm not smart but, I sometimes think I am.

 

Hard to get isolation between 12v and 240v (traction battery high voltage) using an electronic component such as a power transistor. Isolation between the two voltage systems would be the issue in the event of the electronic component failure.

 

was this because at first they forgot ( did not now ) to use the hall effect bypass?