[thingstodo]

I have made some tentative design decisions to move forward on the Electric Motor module, outlined below. Please point out any issues you find. I don't believe that this will be the final design ... in fact, I think that there will be more than one final design ... but I believe this design is a good start.

Executive Summary, since this post is so long ... that I need a SUMMARY!

The design will use a DC motor driven by an open source DC motor controller. The DC motor will be coupled to a Honda Civic manual transmission 1984 - 2005. The power will be supplied by a number of lead-acid deep-discharge batteries. The charger is plugged into an ordinary 120V receptacle. All of these parts interface only to the High Voltage junction Box and the Low Voltage Junction Box, not directly to each other. The interface to the rest of the car is not detailed quite yet.

Details

Looking for `more sets of eyes` to see comment on whether these decisions make sense and will be sustainable. Each section has a title, a list of options, a Plus and Minus list, and a summary with the decision that I think is best.

Motor
There are, in my opinion, 2 obvious choices for the Electric Motor Module. I am not considering purchase of another motor at this time since it would add cost and delay for delivery:
1. my aircraft generator
2. my Netgain 9 inch motor

1. my surplus aircraft generator, separately excited

Plus list
+ it has a mounting plate and a coupler already fabricated for the chev sprint transmission
+ I have it
+ no machining is required if there is a joy coupler on the transmission
+ it is light (under 100 lbs)

Minus list
- the generator is separately excited, so more controls are required, another pair of batteries, field current monitoring, etc
- it is less safe to use, since the field current must be established before applying the armature current
- there is a challenge to mount a cooling fan to the motor. The motor drive end has no holes to allow air flow in
- there are no specs available for this generator. I've read ratings from 15 HP to 21 HP but I have no backup for those numbers. Any information may need to be tested and measured.

2. the Netgain Transwarp 9 inch series wound motor

Plus List
+ the controller handles all of the speed control. No external circuitry is required
+ there are holes in the shroud to allow for an external cooling fan
+ it has a coupler for the motor side, and I have a joy coupler that can be used to drive the chev sprint transmission
+ it is a popular EV motor
+ it is available new from several distributors for 'mass production' of the Electric Motor Modules if that ever is required

Minus List
- a mounting plate will need to be fabricated for either transmission
- a coupler, or half a coupler, needs to be machined for the honda transmission
- it is heavier at just over 200 lbs

Summary
I think that the Netgain motor is the obvious choice. It is a standard motor, it is easily controlled by a commercial DC motor controller. The aircraft generator is more dangerous to control, requires external circuitry or another controller to effectively control torque and speed. The Netgain is more powerful and more likely to be a standard offering for the Electric Motor Module in the future. Applying the Keep It Simple principal - Netgain motor.

Controller
I have two different available DC controllers. Again, I am not considering purchase of a different controller due to cost and delivery issues:

1. Kelly controller - KDHD
2. Pauls & Sabrina's 'ReVolt' Open Source 500A DC Motor Controller

1. Kelly Controller

Plus List
+ it is powered up and operating
+ the rated continuous current is 300A, maximum current (1 minute) is 600A, which is likely more than the batteries can source
+ it is a very simple electrical interface

Minus List
- there are no optional connections
- it is not very powerful
- since it has no optional features, it does not indicate the internal temperature although the manual states that it will cut back current in order to prevent the internal temperatures from failing the components

2. Paul & Sabrina's 'ReVolt' Open Source DC motor controller, Open Source project

Plus List
+ it is more powerful than the Kelly, 500A continuous but no information on maximum current for short periods of acceleration
+ we have drawings for the controller, a Bill of Material, and the files required to produce more boards
+ we have an interface that will communicate the internal temperatures
+ it has self-protection circuits to shut itself down on over-current and prevent damage

Minus List
- mine has not been tested as yet
- it will take some work and some time to test

Summary
The interface for each of these controllers is very similar. My intent is to use the Open Source controller. If there is some issue that cannot be quickly resolved, the Kelly can be used instead. There will not be a large difference either way. Decision to use Open Source. The Kelly will be held as a spare.

Transmission

There appears, to me, to be 3 ready options for the transmission. This section considers purchase, since I have only one transmission and it is not, in my opinion, an ideal candidate for the car:

1 - 5 speed manual from my 1990 chev sprint
2 - 5 speed manual from a 2006-2011 honda civic
3 - auto trans from a 2006-2011 honda civic
4 - added - 5 speed manual from a different year of honda civic

1 - chev sprint

Plus List
+ I have it in a car, available immediately
+ I can measure things on it
+ The transmission runs
+ It has a splined shaft, but the splined shaft also has a joy coupler mated to it, made by the machinist who sold me the car
+ The output shafts of the transmission are available for machining if required
+ It is a very common EV conversion
+ it may not be available new, but you can pick one up used at any wrecker in North America

Minus List
- It may not handle the output torque of the Netgain Transwarp 9 inch motor (it may break)
- The output shafts from the transmission require an adapter to mate with Honda wheels and suspension
- the transmission mounting to the motor module must be fabricated from measurements. Testing is less than ideal

2 - 5 speed manual from a 2006+ Honda Civic

Plus List
+ the transmission is stronger and should handle the output torque of the Netgain Transwarp 9 inch motor
+ Randy at Canev tells me that the DC motor can be reversed with a contactor, and that running at low speed in reverse will not damage the brushes. They do this in their industrial trucks and have not had wear issues.
+ the existing selector for the linear actuator in the car is P, R, D (not sure if there is a neutral?). The standard transmission can be locked in second gear, R will activate a reversing contactor to turn the motor in reverse, D will de-activate the contactor and turn the motor forward.
+ still available new, but can also be picked up from any wrecker in North America

Minus List
- the transmission must be procured and delivered
- it will cost time and money to find it and buy it
- an adapter plate and coupler need to be fabricated since this model of civic is not a popular EV conversion

3 - auto transmission from a Honda Civic

Plus List
+ the output shafts do not require an adapter to mate with the Honda wheels and suspension
+ the transmission is stronger and should handle the output torque of the Netgain Transwarp 9 inch motor
+ the transmission is the same as the gas Motor Module engine
+ The existing linkage available from the WIKISPEED car is Park, Reverse, Neutral, Forward which ALREADY works with this transmission
+ The WIKISPEED shop can measure anything required to fabricate the required motor-to-transmission coupler
+ the transmission mounting to the motor module can be fabricated at the Lynnewood shop using existing designs
+ the transmission is available new from Honda via the existing WIKISPEED agreement

Minus List
- the transmission may or may not shift from 1st to 2nd to 3rd to 4rth gear. This will be a bit of an experiment.
- the motor to transmission 'slips' before lockup so some efficiency is lost when part of the power is lost to slippage. This is not really a big deal at this stage.
- Randy at CanEV has advised against using an automatic


4 - 5 speed manual from a 1984 - 2005 Honda Civic

Plus List
+ the transmission is stronger and should handle the output torque of the Netgain Transwarp 9 inch motor
+ the motor coupler and the transmission adapter plate are available from Canev pre-made
+ Randy at Canev tells me that the DC motor can be reversed with a contactor, and that running at low speed in reverse will not damage the brushes. They do this in their industrial trucks and have not had wear issues.
+ the existing selector for the linear actuator in the car is P, R, D (not sure if there is a neutral?). The standard transmission can be locked in second gear, R will activate a reversing contactor to turn the motor in reverse, D will de-activate the contactor and turn the motor forward.
+ still available new, but can also be picked up from any wrecker in North America

Minus List
- the transmission must be procured and delivered
- it will cost time and money to find it and buy it
- an adapter needs to be fabricated to mate the output shafts of this older style transmission to the 2006+ wheels used by WIKISPEED
- the transmission coupler and adapter plate need to be procured and delivered

Summary
It appeared to me about a week ago that the automatic transmission has many positives and almost NO negatives. After a quick discussion with Randy at CanEV (an EV conversion shop), that has changed. He advises me that there are many problems driving an automatic transmission with an electric motor and advises on the Standard transmission. He did not go into details on the attempts that they have made with their heavy-duty vehicles, but I am inclined to take his advice.

So the added option, number 4, is the tentative path forward. It appears that all the transmissions of this era, 1984 - 2005, have the same mounting to the gas engine so the adapter plate and coupler works. A transmission needs to be sourced so that measurements can be made and the adapter to the wheels can be machined.

The High Voltage Junction Box and Low Voltage Junction Box are part of the design. It may be a challenge to fit everything into the motor module frame.