Tuesday, 26 March 2013

Some More Parts

Some more parts have arrived.
After a lot of searching a suitable DC/DC converter was located at a reasonable price.  Meanwell make a wide range of power supplies including the RSP-1500-12.  This power supply will operate on 127-370VDC and supply up to 125A at 12VDC, perfect noting the additional electrical loads for the power steering pump and the vacuum pump. The output voltage can be adjusted up to 13.5VDC to maintain the auxiliary battery at full charge.

It also has an alarm signal that can be used to drive the original alternator warning light.
The water heater for the cabin also arrived.  Unfortunately the thermostat was damaged in transit.  It looks simple to replace and, as it was sent from the US, hopefully the supplier can provide a replacement thermostat under warranty that they would be happy for me to install.

Water Heater

Two under tray pannier boxes also arrived.  One of these will house the power cord and the other is for balance.  I plan to fit a rotary limit switch to the door to disable the motor controller if the power cord is not secured in the box.

Battery Box Design

Back into SketchUp to design a battery box. 
My first effort (Version 1) was based on 52 x 200Ahr batteries (166V) and used bars designed to fit through the corrugations in the batteries to hold them in.  This was to leave the tops of the batteries free from fittings other than the connections. 
Battery Box Ver 1 - In Situ
This arrangement fits very snugly into the front of the tray with the battery chargers fitted on the left and the contactors and BMS on the right.  The advantages of putting the chargers and contactors in the box is that the high voltage is contained within the battery box when the car is shut down. 
Battery Box Ver 1 - Frame
I think the design is too tight so I am working on Version 2 based on 180Ahr batteries, probably 58 or 60 depending on how they fit.  These batteries are slightly taller and I am hoping to gain some floor space at the cost of some height. The 180Ahr batteries should still fit in the tray without obstructing the rear window from the cab.   The higher battery voltage (approx 196V) is within the specifications of all the components I have bought so far with the exception of the water heater.  If the higher voltage turns out to be a problem I will connect the elements in series and operate the unit at a lower power output. 

Monday, 25 March 2013

Motor Mount Fabrication Begins

After a bit of a false start we started the welding for the motor mount today.
I got all the individual pieces for the motor mount cut a couple of weeks ago.  A company in Queenbeyan cut them for me using a very cool computer controlled profile cutter normally used for cutting glass and ceramics but which could also be used for steel and wood (they can cut 10mm MDF without any noticable swelling at all). 
Unfortunately in my original model I forgot to include the studs for the power cables on the side for the motor and the lower A/C mounting plate ended up being in the same place as one of the studs.  To move the mounting plates out by 25mm I added two small "fixit" bits to the front plate (shown below in white) and widened the top plates.  Lesson for first time 3D CAD modelers - model all parts of the components and ot just the major bits!  

Motor Mount Ver 2
The photo below shows the front plate with the "fixit" bits added and the power steering pump mount tacked on.

Motor Mount Fabrication
Next step is to sort the mounting arrangements for the A/C compressor and the vacuum pump which go on the other side. 
The photo below shows the main part fully welded with the power steering pump and vacuum pump fitted up.
Motor Mount Initial Fit Up

Tuesday, 29 January 2013

Motor Mount Design

Pulled the radiator out to make some measurements for the motor support last weekend.  The basic idea is to mount the controller, A/C compressor, power steering pump and the vacuum pump all with the motor on the existing motor mounts.
Trimble publishes a free CAD package called SketchUp which was used to model the main components and their locations.  The image below shows the overall arrangement.  The motor is in the middle in red.  The A/C compressor is on the left hand side as close to its existing position as possible hopefully not requiring any change to the existing piping.  The A/C compressor will be driven from a 150mm pulley fitted to the non-drive end of the motor and the existing idle pulley will be used to tension the A/C drive belt.  The vacuum pump is also on the left hand side behind the A/C compressor.  The power steering pump is on the right hand side, again close to the position of the existing pump in an attempt to minimise changes to existing hydraulic piping.  The controller is on the top of the motor to minimise the length of cable that carries the highest current.
Arrangement of Main Components
The image below shows the motor support on its own.
Motor Support From Below
The angles with the end plates are separate from the rest of the support and will be located on the existing engine mounts.  The end plates will be bolted to the front plate and the adaptor plate on the bell housing.  The bolt holes will be marked with the assembly in the engine bay.
The plan is to get the pieces of plate and angle cut by a local supplier and then spend some time in the shed aligning things and welding it all together.  Hopefully the entire assembly can be lifted into the engine bay in one go when it comes time to take the vehicle off the road. 

Wednesday, 11 July 2012

Back on the job....

After a spell of almost a year related to a small matter of money, I have got back to work on the electric hilux. As we use the hilux nearly every day, the plan is to assemble all the components that need to go in the engine bay and build a battery box before removing anything from the donor vehicle. First stop is the motor and associated mounting frame. To make things as simple as possible, I intend to retain the original gearbox and the clutch.
The design calculations indicated a 9inch DC motor would be able to provide sufficient power and torque. Both Advanced DC and Netgain make suitable motors.  The information available for the Advanced DC FB1-4001A indicates a rating of 144V while the Netgain WarP9 is rated at 196V.  So a WarP9 is now in the shed.
WarP9 Motor
Canadian Electric Vehicles (www.canev.com) manufactures off the shelf adaptor plates for many different types of vehicles including a Toyota S22 engine. They appear to be on sold by a number of other companies. As I like to buy from the original equipment manufacturer I ordered one and 6 weeks later it arrived from Canada. These adaptor plates come with a coupling to fit the original flywheel and clutch onto the electric motor shaft.
Adaptor Plate and Flywheel Adaptor
I plan to mount any reciprocating auxiliary components together with the motor on the original engine mounts. As the electric motor is a bit shorter than the original petrol motor, I will try and fit all the auxiliary components at the front of the motor to take some load off the gearbox mount.
I will need a power steering pump and a vacuum pump as new equipment and I plan to keep the original air conditioning compressor. 
12V Power Steering Pump

Vacuum Pump
As the motor controller should also be as close as possible to the motor, it will be mounted on the motor assembly as well, directly above the motor. Time to order this.
Next task is to take some measurements of the location of the engine mounts and the arrangement of the air conditioning compressor. I also need to source a suitable v-belt pulley to mount on the free end of the motor for the compressor and some steel to commence design and fabrication of the engine mount.

Tuesday, 26 April 2011

Donor Vehicle Selection and Purchase

The basic requirements for the donor vehicle were:
- seating for two adults and one child;
- enough load carrying capacity to use lead acid batteries required for the approx 100km range (>800kg);
- enough space to include batteries;
- air conditioning;
- less than $5000.

The 1996 Toyota Hilux single cab is a good choice as it has:
- three seats in the front (the middle is a bit small but should be suitable for a child if all three of us want to go somewhere);
- a tare weight of approx 1350kg and a GVM of approx 2700kg so there is lots of weight margin for batteries if the range ends up being too low;
- the single cab means that most of the batteries can go behind the cab to keep the weight balance good;
- has a carburetted engine so there will be no ECU to be confused when the engine disappears.

I watched three car sales web sites every day for 6 weeks.  This one was advertised in Sydney for $6990 - out of our price range but worth a look to see what could be had for some more money.  When I went to look at it I told the dealer what I wanted to do with it and our budget.  Apparently he had paid more for it than I offered.  I asked him to call me back if he changed his mind.  Three weeks later he did and we got our donor vehicle. 
The Donor Vehicle

On the drive back from Sydney we had a bit of a scare as the engine cut out on the way up a hill on the freeway - not a good sign. 
Luckily it was just a blocked fuel filter and easily fixed.  There are no rattles or squeaks, the air conditioning works, the radio might need replacing and some seat covers won’t go astray.