[WIP] L322 RR Vogue - The beached whale

[nkiernan]

Electrical:

The list of components and interlinked systems adds up quickly, so have been laying out a general schematic to help me get my head around what needs to happen! These are still work in process and I will continue adding more detail such as the low voltage system.

Lots of various discussions on the forum around the right way to set things out but depends on what the project will allow. Here, the two battery boxes are tucked underneath with a 3m to 4m run of HV cables to the HVJB in the front. I'm considering separate fuses and contactors in each of the battery boxes, but in order to keep good access to the ISA shunt and CAN buses etc, it looks like the neatest way is to double up the positive and negative contactors in the HVJB. This means seven contactors including the charging contactors though, so maybe some overkill I can simplify.

I also need to figure out the interaction between some of the controllers. Both the LIM and PCS controller expect CP and PP signals but these can't be used by two controllers. Some work to do here.

Open to any comments or suggestions to correct errors, or simplify things, or address any safety requirements!?



Electrical schematic WIP:

RRV_Elec.pdf

(268.99 KiB) Downloaded 515 times

Schematic with cooling/heating system hidden:

RRV_Elec-Model_Less-Cooling.pdf

(190 KiB) Downloaded 596 times

[johu]

I'd at least drop the negative relay in the HVJB, more likely I'd drop all 3 battery relays there and move precharge to box 2 next to the B+ relay. That way the long run back to front is unpowered with the vehicle off and so is the HVJB.
Or maybe I haven't understood why you want to double up the relays

[nkiernan]

Thanks for your reply Johu.

Ideally I don't want to double up relays so your suggestion would be much tidier. I do want the HVJB and cable runs from battery to be unpowered when car is off, but was thinking I needed the ISA shunt the battery side of the main contactors. I want the shunt in the HVJB for accessibility for now at least, so that is where the second set of contactors came from.

Thinking about it more, the ISA shouldn't need to be battery side so your suggestion makes good sense.

[johu]

Yes, I'd be surprised if there was current flow across the ISA shunt while the battery box relays are off

[Alibro]

Some great fabrication there mate, well done, it puts my efforts to shame big time
And your RR will be very nice when it's finished.
BTW I watched Calvin and his mate dismantle a model 3 battery pack last April while I was picking up my eGolf pack, could it have been yours?
I was impressed by how careful they were while working at it. I also was happy by the description of the pack I picked up. It was described as coming from a car with 250 miles on it and when collecting the pack the car definitely matched the description so they seem to be a good bunch to deal with.

[nkiernan]

BTW I watched Calvin and his mate dismantle a model 3 battery pack last April while I was picking up my eGolf pack, could it have been yours?

Thanks Alibro.

Yes, that might have been my pack at EVBreakers. I saw that golf with the low miles just in so it was around that time alright

[Bratitude]

I’d put positive contactor/precharge and positive ccs contactor in the battery box. delete negative contactor in the HVJB, and run pcs threw the positive ccs contactor.

this way your not running pcs or ccs through pre charge at any point accidentally. And you cut back on contactors and the HVJB size

[nkiernan]

I’d put positive contactor/precharge and positive ccs contactor in the battery box. delete negative contactor in the HVJB, and run pcs threw the positive ccs contactor.

this way your not running pcs or ccs through pre charge at any point accidentally. And you cut back on contactors and the HVJB size

Thanks for the suggestions Bratitude. I'm going to rejig the layout tomorrow and see how it looks. I've left myself tight on space in the battery boxes, but with the space in the engine bay I have a good size electrical/HVJB I can make use of so might have to come to a bit of a compromise with the CCS contactor location.

Not just sure what you mean re the CCS positive and the PCS. I tried laying it out as it is in the TM3 battery pack. If I understand what you're saying, you'd run the PCS positive cable through the CCS positive, so the CCS positive would have to come on for drive and charging?

[nkiernan]

HVJB / Electric:

Maybe a little prematurely (some layout mods being discussed in previous posts ), but I've been looking at a neat way to house the TM3 PCS, the VCU and controllers, and contactors etc in the engine bay. With no batteries being mounted in the engine bay, this leaves a lot of space above the motor. I have a rough idea where things like the steering pump and brake vacuum pump and accumulator are going so time to get things mounted.

Originally I had planned for the battery and precharge contactors, as well as the CCS charge contactors to be housed here, but after some suggestions on better layout, I'll see what I can move to the battery boxes and this will free up space for the BMS possibly. The VCU, PCS controller and LIM will mount on the outside edge of the enclosure near to the RRV engine electrical box

Played around with a number of layouts. Plan is for the CCS combo charge port to mount at the front, somewhere behind the front grill. Was a tight fit where the original fuel filler would have been, and makes it tidier to have everything close in the engine bay anyway

[nkiernan]

HVJB / Electric:

Drew up an enclosure to be laser cut in aluminium. I didn't have a way to fold properly, so I stitched the fold lines to allow it to be folded by hand and these would have to be welded later on. Was looking for a clean design (to bug anyone looking for the V8 later on ) but wanted to steer away from just rectangular. This added complexity to the flat pattern and folding etc, but as its one piece and hand folded it worked out. I have a single aluminium lid for now but could consider smoked perspex later, depending on what might be worth seeing inside

Some test fitting. HV battery cables through the rear as well as the feed out to the inverter. CCS charging HV cables in through the front. Reusing the TM3 connectors for 12V, auxiliary, AC charging, cooling, etc so essentially remaking a Tesla Model 3 penthouse!

Electrical components will mount on a removable backplate. M6 rivnuts used to give threaded mounts for the lid and controllers. Not good for the IP rating but thinking about what to do for that

Welded up

[Bratitude]

Not just sure what you mean re the CCS positive and the PCS. ……..
you'd run the PCS positive cable through the CCS positive, so the CCS positive would have to come on for drive and charging?

oh no sorry I mean the pcs positive would share the same contactor as the positive end of ccs. (Which is in parallel with the main positive/pre charge - connected to the battery)

Pcs negative would be on the main Negative contactor

Ccs has its own negative contactor.

Just cuts down on contactors, that’s all


just cuts down

[nkiernan]

Electrical:

A revised electrical layout following some comments by Johu and Bratitude. Modified to show how the PCS will be inside the enclosure and moving some contactors to the battery boxes. Tight on space in the battery boxes but should fit this much

Am I correct that pre-charge is needed at the start of charging in the same way it is for powering up the inverter? Is this for the batteries or because the inverter see's HV during charging in this sort of setup (just the inverter has no 12V/run signal)? Is this acceptable?

Bratitude, you mention separating PCS and CCS from the pre-charge, but I'm still not 100% sure how you mean and I thought I needed to have the pre-charge when charging also. Showing a rough layout of my understanding below but think you mean PCS + to the other side of the + CCS contactor but then I'm seeing extra HV cables between HVJB and Battery box or live CCS + charge port pins during normal running? Know I haven't picked up what you're describing correctly

Revised Electrical layout:

RRV_Elec.R1.pdf

(266.81 KiB) Downloaded 523 times

[SuperV8]

HVJB / Electric:

Drew up an enclosure to be laser cut in aluminium. I didn't have a way to fold properly, so I stitched the fold lines to allow it to be folded by hand and these would have to be welded later on. Was looking for a clean design (to bug anyone looking for the V8 later on ) but wanted to steer away from just rectangular. This added complexity to the flat pattern and folding etc, but as its one piece and hand folded it worked out. I have a single aluminium lid for now but could consider smoked perspex later, depending on what might be worth seeing inside


Welded up

020.JPG

That is a great idea - i'll be borrowing in the future!!

Who did you use to laser cut?

[nkiernan]

Who did you use to laser cut?

A company called Four Dee NI (www.4d-ni.co.uk). Have been really helpful for small one off orders for this project and a few others

[Phate]

What sort of roadblocks did you run into to kill the plan to use the GS450H transmission with the original transfer case?

Or was it just a case of having more room than expected to use a separate drive unit on each axle?

I'm not quite at the "buy parts" stage yet, but I have an older Nissan D22 that would be a fairly easy conversion if I can use the truck's original transfer case.

[muehlpower]

I like the circuit diagram a lot, I'm just wondering about the position of the main fuse. I would install it in the line to the battery, then the CCS port is also fused. And there is no need to connect the CP and PP signal to the PCS control. Both signals can be handled by the LIM and are available in the CAN bus.

[Bratitude]

Electrical:


Am I correct that pre-charge is needed at the start of charging in the same way it is for powering up the inverter?

There is no need for recharging the pcs.

precharge is only for the drive inverter to protect the drive inverter igbt’s from inrush currents and voltage spikes. It just slowly charges the capacitors up, instead of instantly.

the reason to not have other HV components connected to your main/precharge path is if the pcs or anything else were to draw power during precharge, you’ll most likely blow up the precharge resistor.

[muehlpower]

Electrical:


Am I correct that pre-charge is needed at the start of charging in the same way it is for powering up the inverter?

There is no need for recharging the pcs.

precharge is only for the drive inverter to protect the drive inverter igbt’s from inrush currents and voltage spikes. It just slowly charges the capacitors up, instead of instantly.

the reason to not have other HV components connected to your main/precharge path is if the pcs or anything else were to draw power during precharge, you’ll most likely blow up the precharge resistor.

I do not think so. In any case, the capacitors must be charged slowly in order to protect the contactors. It is also no problem to connect all HV components firmly to one another and to supply them with power both when charging and when driving. Of course, you can only demand performance when the main contactor is closed. So only enable DC/DC converter, A/C compressor, heater, motor, charger etc. after the main contactor is closed.

[johu]

Agreed, usually any HV equipment has capacity inside that you want to precharge.
The PCS can precharge itself and other components on the DC bus by transferring power from the 12V battery to the HV side. Makes the precharge resistor redundant. Not that it is supported in the recent firmware...

[nkiernan]

What sort of roadblocks did you run into to kill the plan to use the GS450H transmission with the original transfer case?

Or was it just a case of having more room than expected to use a separate drive unit on each axle?

It's to do with the amount of extra space that could be gained for batteries if I went that direction. With separate motors for each axle, the transfer case and prop shafts front and rear are removed, and that could double the space underneath for batteries. I'm continuing with the GS450H and the original RRV transfer case for now though to see how it all works. I not just 100% convinced on the true 4x4 ability of the dual motor setup.

[nkiernan]

I like the circuit diagram a lot, I'm just wondering about the position of the main fuse. I would install it in the line to the battery, then the CCS port is also fused. And there is no need to connect the CP and PP signal to the PCS control. Both signals can be handled by the LIM and are available in the CAN bus.

Thank you for the comments Muehlpower, Bratitude and Johu, that helps me a lot. I've moved the main inverter fuse and deleted the CP/PP line to the PCS controller. Yes, I'm assuming the PCS controller is not controlling the PCS pre-charge function for now but this may be a neat revision in a future firmware update. Like others, I still need to get the PCS properly functioning. The final piece of the puzzle to settle on now is the BMS

RRV_Elec.R2.pdf

(266.43 KiB) Downloaded 423 times

[Phate]

It's to do with the amount of extra space that could be gained for batteries if I went that direction. With separate motors for each axle, the transfer case and prop shafts front and rear are removed, and that could double the space underneath for batteries. I'm continuing with the GS450H and the original RRV transfer case for now though to see how it all works. I not just 100% convinced on the true 4x4 ability of the dual motor setup.

Gotcha, yeah there is definitely a lot of room in the center tunnel.

Extremely interested in what you come up with for attaching the GS transmission to the original transfer case. I also have the same concerns regarding the dual motor setup - at low speed in slippery conditions there's a lot of value in having things mechanically linked. OEM's can make it work with software (grabbing the brakes on any wheel that breaks traction and spins up), but that seems like it would be more difficult on a DIY build.

Also, didn't the Range Rover come with locking differentials? Those would certainly be more useful than the open diff(s) you'd find in pretty much any EV drive unit.

In my case I have a fairly simple pickup truck with a mechanical transfer case that just shifts between RWD high/4WD high/4wd low using a lever, and a straight axle with leaf springs in the rear. If I can keep the transfer case I don't need to modify the suspension, differentials, hubs, or driveshafts. It also is probably more efficient to drive it around in 2wd instead of being AWD/4WD all the time.

[nkiernan]

Extremely interested in what you come up with for attaching the GS transmission to the original transfer case. I also have the same concerns regarding the dual motor setup - at low speed in slippery conditions there's a lot of value in having things mechanically linked. OEM's can make it work with software (grabbing the brakes on any wheel that breaks traction and spins up), but that seems like it would be more difficult on a DIY build.

Because of the length of the battery boxes underneath, the transfer case has to move forward from its original position. If I could have left it in its original position, I looked at the option to direct couple the GS450H gearbox and the transfer case similar to how the original RR gearbox mounted. The GS450H gearbox is a larger diameter though so would have been tight in the tunnel. This would have left the engine bay clear also.

However, with moving the transfer case forward, I will lengthen the rear prop shaft and shorten the front prop. I have a spare rear prop shaft that will provide the center piece for lengthening, which leaves the CV ends to be made into a short drive shaft between the GS450H box and the trasfer case. Not my ideal scenario but one I'll test. The GS450H box now sits in the engine bay due to position of the transfer case but because of the front diff and steering rack etc, it has to sit slightly right of center and higher than the transfer case.

As you say though, the diffs and transfer case from the RR are definitely more suited to the job for now, so happy to retain them at the minute. I like your option to have RWD or 4WD setup. I did wonder if the RR transfer case could be made to allow similar as it has a controllable clutch setup!

[nkiernan]

Battery Boxes:

The battery boxes are designed to accommodate the stubs for the battery module terminal connections as the space available for the batteries meant the overall length was restricted. This will allow me to work with the contactors etc on top of the battery boxes and this fits in the space where the fuel tank would have been

The idea was to let the stubs protrude up through the lid of the battery boxes, along with the mid pack terminal connection point and possibly the BMS harness

Looks like a standard enclosure could work well for this, and provides a back-plate for the contactors and fuses and leaves an easily serviceable access point rather than having to remove the battery box lid if needed

Trying out a few component layouts between the HVJB and the battery box junction boxes to find the simplest layout

[nkiernan]

Mechanical:

Must be getting confident there won't be any more chopping and changing, the paint cans are out!


Parts for mounting the inverter and front axle tube

Anti-vibration mounts for the HVJB frame

Final test fit for the transmission and differential mounting frame to locate the anti-vibration mounts for the transmission

Test fit for the HVJB frame before building up the HVJB

Transmission frame assembly which needs the front differential and axle supports mounted next