Search found 266 matches

by francisco.shi
Sun, 16 Feb 2020, 04:59
Forum: Members Machines
Topic: Francisco's Electric Pajero
Replies: 126
Views: 14289

Re: Francisco's Electric Pajero

About the quietness the inverter is running at 7khz and surprisingly there is no 7khz noise coming from the motor. I was very surprised. However when I lift the wheels and run it there is a lot more noise from the diff gears than I was expecting. I have to wait and see how noisy it is once it is dri...
by francisco.shi
Sat, 15 Feb 2020, 16:32
Forum: Technical and conversion discussion
Topic: Prelude conversion project - some questions
Replies: 544
Views: 43813

Re: Prelude conversion project - some questions

Any chance the charger or DC-DC converter for 12v may be causing the problem?
by francisco.shi
Wed, 12 Feb 2020, 04:01
Forum: General EV Discussion
Topic: Aussie electric vehicle sales triple in 2019
Replies: 15
Views: 412

Re: Aussie electric vehicle sales triple in 2019

My guess is that an electric drive train excluding the battery is considerably cheaper than an ICE drive train (engine + transmission + exhaust etc) so it seems the price we are paying is the price of the original ICE car + the price of all the electrics. No discount for not having the ICE.
by francisco.shi
Tue, 11 Feb 2020, 22:05
Forum: General EV Discussion
Topic: Aussie electric vehicle sales triple in 2019
Replies: 15
Views: 412

Re: Aussie electric vehicle sales triple in 2019

I think car makers are making as much as they can from the electrics. I don't believe an electric drive train costs that much more than the ice drive train. Batteries have come down significantly. I am sure the car manufacturers can already get the cost of the cells close to the magic $100/kwh.
by francisco.shi
Wed, 05 Feb 2020, 15:27
Forum: Members Machines
Topic: Francisco's Electric Pajero
Replies: 126
Views: 14289

Re: Francisco's Electric Pajero

I think it is too bad. It has no brakes. Only regen braking :twisted: It is good enough to hold it on a slope.
by francisco.shi
Tue, 04 Feb 2020, 16:23
Forum: Members Machines
Topic: Francisco's Electric Pajero
Replies: 126
Views: 14289

Re: Francisco's Electric Pajero

I bought a rolling chassis from the wreckers so I could do the testing and measurements without having to pull apart the one I am using. Once I get everything right I will pull apart the real one and transfer everything across. Because the motors and battery are all one unit I expect it will take lo...
by francisco.shi
Mon, 03 Feb 2020, 17:17
Forum: Technical and conversion discussion
Topic: VW T3 syncro conversion
Replies: 7
Views: 359

Re: VW T3 syncro conversion

If you want motors let me know.
by francisco.shi
Mon, 03 Feb 2020, 17:14
Forum: Members Machines
Topic: Francisco's Electric Pajero
Replies: 126
Views: 14289

Re: Francisco's Electric Pajero

A bit of a test drive.

Just testing the mechanics and the gate drive. So far only running one motor at 30% of peak torque.
by francisco.shi
Sun, 02 Feb 2020, 05:02
Forum: Batteries, charging, management and monitoring
Topic: Weber & Coulomb's LyteFyba BMS
Replies: 72
Views: 30920

Re: Weber & Coulomb's LyteFyba BMS

The flurocarbon coolants are extremely expensive and have to be kept in an airtight loop. They absorb water which makes them conductive.
I was considering to use them for a cooling loop in a 3kv inverter. After funding out about the problems I decided that air cooling was good enough.
by francisco.shi
Thu, 30 Jan 2020, 14:06
Forum: Members Machines
Topic: 4Springs' Brumby
Replies: 247
Views: 44052

Re: 4Springs' Brumby

Could you use a heater element from a bag sealer?
They are a thin strip about the thickness of the tape. I would expect the thickness to be thin enough that you will not mark the cells.
by francisco.shi
Sun, 19 Jan 2020, 05:39
Forum: The Lounge
Topic: hello, new here
Replies: 8
Views: 383

Re: hello, new here

The motors I was looking at were about 15krpm. A friend had one of those 4 cylinder 250cc. They sounded like you were going top speed and then he would come around the corner doing 40kph. It was really funny. I wonder how many times cops took off thin king some one was speeding around the corner onl...
by francisco.shi
Sat, 18 Jan 2020, 18:34
Forum: The Lounge
Topic: hello, new here
Replies: 8
Views: 383

Re: hello, new here

In the case of the motorbike it is not a problem. The old engine redlines at 11krpm. So the gearbox is already geared correctly.
by francisco.shi
Fri, 17 Jan 2020, 17:51
Forum: The Lounge
Topic: hello, new here
Replies: 8
Views: 383

Re: hello, new here

I have an old engine for my dirt bike and the other day I saw some 30kw RC airplane brushless motor and started thinking of doing the same. I just didn't have the courage to do all that.
by francisco.shi
Thu, 16 Jan 2020, 11:17
Forum: Members Machines
Topic: 4Springs' Brumby
Replies: 247
Views: 44052

Re: 4Springs' Brumby

I think you are being too aggressive. I think I used some 600 sand paper and did it by hand. Only a few strokes and then quickly applied the contact grease. Then they could sit for a few min while I did the other tabs. From memory I think I folded the sandpaper and did both sides of the tab at the s...
by francisco.shi
Thu, 16 Jan 2020, 09:20
Forum: Members Machines
Topic: 4Springs' Brumby
Replies: 247
Views: 44052

Re: 4Springs' Brumby

Only the copper tabs are nickel plated. I had a lot of trouble with contact overheating on the aluminium tabs until I removed the oxide and applied contact grease.
by francisco.shi
Thu, 16 Jan 2020, 06:30
Forum: Members Machines
Topic: 4Springs' Brumby
Replies: 247
Views: 44052

Re: 4Springs' Brumby

You just need to polish them to remoce the oxide layer and quickly apply some electrical contact grease and clamp them. That is what I did and it seemed fine the contact resistance was as low as the contact on the copper side.
by francisco.shi
Wed, 15 Jan 2020, 12:30
Forum: Members Machines
Topic: Francisco's Electric Pajero
Replies: 126
Views: 14289

Re: Francisco's Electric Pajero

I am not expecting it to be able to spin the wheels. That means that a highlux on low range and 1000kg on the back will pull the Pajero. As much as it looks impressive for a Tesla to drag a Ute it is all about grip. Any old Ute with enough weight on the back and in low range will drag any Tesla any ...
by francisco.shi
Tue, 14 Jan 2020, 07:43
Forum: Members Machines
Topic: Francisco's Electric Pajero
Replies: 126
Views: 14289

Re: Francisco's Electric Pajero

Yes. It already does regen. The current processor is too slow to run the motor smoothly at full speed and it doesn't have enough pwm outputs to run the resolver and the 3ph bridge. So I will use a different processor on the final version. This setup is so that I can test the structural strength of t...
by francisco.shi
Sun, 12 Jan 2020, 20:18
Forum: Members Machines
Topic: Francisco's Electric Pajero
Replies: 126
Views: 14289

Re: Francisco's Electric Pajero

I have been doing some further testing of the power stage. This time driving the motor. I put some wires between the motor and the power stage because I can't get to the components when it is mounted to the back of the motor. I got a friend to lend me a board he has been using to learn about Field O...
by francisco.shi
Fri, 03 Jan 2020, 11:46
Forum: Technical and conversion discussion
Topic: My vision of a low cost electric super car
Replies: 6
Views: 407

Re: My vision of a low cost electric super car

You may be better off using a motor designed for EVs. By the time you rewind the industrial motor you will have spent not much less than buying a motor for an EV. Also the EV motors are water cooled so they will give you better performance.
by francisco.shi
Fri, 03 Jan 2020, 05:00
Forum: Members Machines
Topic: Francisco's Electric Pajero
Replies: 126
Views: 14289

Re: Francisco's Electric Pajero

I didn't know about the VESC project.
I think it is a good idea to use existing hardware.
Maybe we should start a similar project for EVs.
by francisco.shi
Fri, 03 Jan 2020, 04:40
Forum: Members Machines
Topic: Francisco's Electric Pajero
Replies: 126
Views: 14289

Re: Francisco's Electric Pajero

It is mostly my own design. The DC-DC converters (the 3 transformers with associated drivers oscillator and rectifier on the secondaries) is a pretty standard way of doing isolated psu for gate drives. I just used newer parts for the transistors that drive the primary. There are two transistors in o...
by francisco.shi
Fri, 03 Jan 2020, 04:17
Forum: Members Machines
Topic: Francisco's Electric Pajero
Replies: 126
Views: 14289

Re: Francisco's Electric Pajero

I think they are very good cells. Having the tabs on opposite sides makes it easy to connect them together and reduces the amount of copper you need for busbars.
by francisco.shi
Thu, 02 Jan 2020, 09:43
Forum: Members Machines
Topic: Francisco's Electric Pajero
Replies: 126
Views: 14289

Re: Francisco's Electric Pajero

I have been a bit busy for a while and didn't really have time to work on the Pajero. I have managed to get back into it and I am now working on the inverter to drive the motor. I got the gate driver board made. 15779286035601025195610.jpg Here is a picture of the power module. 157792875744714568428...