Peter Holderith recently published an article on “The Drive” stating that motor controllers aka inverters for EV conversions were suffering a large supply shortage.
It seemed that he completely missed out on second hand inverters and entire drivetrains from not only full EVs but hybrids as well. Today, we want to fill that gap by going over some of the most popular (hacked) EV inverters.
Before we start let’s summarize that we are mostly talking about 400V technology here. So the inverter takes something from 300-450V from a lithium battery pack and converts it to 3-phase current to control the torque of the attached electric motor. The main difference between the various inverters is how much current they can handle, which ultimately tells us what sort of power we can expect from a given inverter.
Let’s start with the main actor in our book “Deep Dive EV Conversion” and the one featured next to the title of this post. It is the Nissan Leaf inverter. It exists in 3 generations. They can all be used unmodified using Damien Maguires “Zombieverter” and output between 80 to 160 kW. The 2nd generation can also be run with a modified openinverter controller to run not just the matching Nissan Leaf motor but in fact any motor in the matching voltage range.
On ebay you can find many of them at prices starting around 400€ for just the inverter or 1200€ for the entire “power tower” consisting of motor, inverter, DC/DC converter and battery charger. Mind you, it is so tall that only motor and inverter fit into most cars.
These are not just inverters but real power houses. They consist of 2 inverters, one good for around 100 kW the other for 50 kW plus a DC/DC converter. Hop on ebay and you’ll find them starting at prices as low as 100€. Add another 200€ and you’re supplied with the matching hybrid transmission, powerful enough to run a small car on its own without the pesky fossil burner attached.
But even for other motors these inverters are a great choice, be they from a smart, a Hyundai or other motors whose inverter has not yet been hacked.
On we go with perhaps the most commonly used drive train in EV conversions, the motors from the market leader’s Model S, X, 3 and Y cars.
They come in 3 flavours. The motors from the older Model S and X exist as a small and a large drive unit. The top-range large drive unit is capable of 400 kW or more, the smaller one delivers 200 kW. They can be run with openinverter control boards that replace Tesla’s original controller boards.
The Model 3 and Y drive units can be run with various VCUs (vehicle control units) that spoof the inverter into thinking it is still in its original car. Unfortunately, the VCUs cost about as much as the drive units themselves.
Tesla motors are not cheap in general, starting at 2500€ for the small drive unit and up to 5000€ for the large one making these the choice for performance-minded enthusiasts.
An increasingly popular budget choice are the Mitsubishi Outlander drive trains. Each car has two, a smaller one for the front and a larger one for the rear axle. They are rated around 70 kW each. A bit less for the front, a bit more for the rear.
They are also easy to run with Damiens Zombieverter and will only set you back a mid 3-figure price in euros.
Lexus builds a number of rear-wheel drive hybrid cars. Conveniently the transmission usually slides right into the transmission tunnels of most similar sized rear-wheel drive cars. Its performance figures are impressive at around 150 kW from its two integrated motors. It is paired with an inverter that allows driving this impressive power into the motor terminals.
Damien Maguire’s love for older rear wheel drive BMWs has made these the ideal choice for him. So unsurprisingly, the Lexus drive train was one of the first to be supported by the Zombieverter VCU. That means no board swaps are necessary but a simple hookup to Damiens control box suffices.
Inverter and transmission combined set you back about 1000€. Watch out to get as much of the wiring loom with it as possible, as it is hard/expensive to source otherwise.
The motor/inverter combos described above are merely the tip of the iceberg. As you can see they can be had for rather reasonable prices and a quick ebay search reveals that there is plenty of supply.
For us in Germany, converters matching inverter/motor combos are very convenient and important as they do not require (expensive) EMC testing of our converted cars.
We hope one of them caught your attention and that you can score a good price on ebay or the scrap yard. Happy building!