|Owner||Mike and Dave|
|Location||Brisbane, Queensland Australia map|
|Vehicle||1990 Mazda MX-5 |
Sporty convertible with low centre of gravity and excellent road holding; original ICE was 1.6 L
|Motor||Asea Brown Boveri 3GAA 131 008E 3-Phase AC|
22 kW (cont @ 230 Vac, 50 Hz), 2 pole, long 132 frame, Aluminium frame
|Drivetrain||Standard 5-speed manual gearbox and clutch; using 3.636:1 diff in place of stock 4.3:1.|
|Controller|| Tritium Wavesculptor200|
165 kVA 450 Vdc
|Batteries||228 CALB/Skyenergy SE40AHA, 3.29 Volt, Lithium-Ion|
Sky Energy SE40AHA Lithium Iron Phosphate x 212 via bulk buy from EV Components. Added another 16 from EV Works. Stage 1: 375 V; stage 2: 750 V
|System Voltage||375 Volts|
With CAN bus option.
We have two of these now.
|Heater||2 x 500 W ceramic PTC heaters (not installed yet)|
|DC/DC Converter|| |
We hope that 2x Meanwell HLG-240H-15A power supplies in parallel across each half of the pack will be enough
|Top Speed||75 MPH (120 KPH)|
Stage 1: est 120 km/h; stage 2: est 160 km/h
|Acceleration||Unknown; will be better than original ICE|
|Range||100 Miles (160 Kilometers)|
Est 160 km
|Watt Hours/Mile||322 Wh/Mile |
Est 200 Wh/km.
|Seating Capacity||2 adults|
|Curb Weight||2,163 Pounds (983 Kilograms)|
Before conversion. Engine and gearbox combined are 170 kg.
|Conversion Time||Not finished yet; started in February 2009.|
Spent months developing analogue BMS; abandoned.
Spent well over a year (1-2 days per week) on digital BMS development.
|Conversion Cost||Batteries AUD 13K (212) + AUD1K (16)|
Controller AUD 7K inc GST
Motor AUD 2600
Chargers US$ 649 each plus import costs but including freight (US$ 165) and CAN interface
DC/DCs AUD 440
|Additional Features||Replaced manual steering with power steering|
Keeping existing air conditioning
Upgraded brakes to NB model 250 mm disks all wheels
Upgraded to NB8B 3.636 differential
|Attempting to produce a sporty conversion with better performance than the original. We planned to do more MX-5s to amortise the learning costs over several conversions.|
2009/Apr: the engine is out. Still considering two lithium battery options: 40AH Thunder Sky, or 30AH China Power (high discharge versions).
2009/June: Sky energy batteries ordered weeks ago; controller arrived; motor almost ordered (just waiting for final options). Motor will take 5 weeks to manufacture and 9 weeks (!) to ship.
2009/Oct/13: Batteries arrived months ago; started battery racks. BMS PCB design completed and prototype arrived. Motor ordered and now due late December.
2009/Dec: Having completed an analogue BMS design, we're now considering a redesign using a microcontroller per cell. Three battery cages are welded (no cells installed yet).
2010/May: Decided to switch from industrial controller to Tritium Wavesculptor200. Motor has arrived, and we have a plywood "adapter plate" for measurements.
Completed the digital BMS design; testing prototypes. Almost complete on 5 battery boxes.
2010/July: Installed potbox.
2010/Nov: Tritium controller and motor are home from dyno testing
2010/Dec: Installed custom flywheel.
2011/Jan: Got the motor running from 24 VDC.
2011/Feb: Driver Controls is talking to both BMS and charger, cutting back charger on over-voltage, and detecting all BMUs (Battery Management Units) in bypass.
2011/Mar: Motor coupled and installed (still needs final balance)
2011/May: still tweaking BMS. Using industrial fibre.
Chasing measurement glitches.
2011/June: First drive with one battery box (28 cells; 93V). Video: WebPage .
2011/Sep: All battery boxes complete and painted. Now concentrating on getting the car ready for the Brisbane EV festival.
2011/Oct: Air conditioning bracket completed, also mounts vacuum pump, starting contactor boxes. Power steering pump mounted. Three battery boxes installed. Frame for mounting two under-bonnet contactor boxes made and painted. Three contactor boxes completed; controller pre-charges and connects to the pack with the key-switch now. It moved under its own power for the Brisbane AEVA festival.
2012/Jan: Three battery boxes (of 8) are complete. Still chasing possible BMS comms problems. Had setback with pre-charge resistor exploding: adding thermal cutout, redesigning 12 V wiring. Repositioning motor controller to allow space for two more contactor boxes.
2012/June: BMS testing is complete, final PCBs have arrived, parts about to be ordered. Motor controller repositioned. Started installing cells into next battery boxes. Boot floor reinstalled.
2012/July: BMS parts arrived, started loading components using a frypan and a rework station (the latter mainly for the bypass resistors). Two more battery boxes are ready for BMUs.
2012/Sep: The BMUs are finally manufactured. Starting the last battery boxes in earnest; installing BMUs in all boxes.
See also our AEVA Member's Machines page: WebPage