New "TSDZ2 Torque Sensor Central Motor"

[casainho]

So, I am developing and testing on a bad quality dual suspension bike. I could not found a good way to place the motor and at start I just let it rotate against the bike frame... and after some testing, it cracked as seen on the picture -- please be warned. Now, I put a metal clamp... you can see this can't work for bike that I will ride.

 

[casainho]

Running TSDZ2 at 62.2V
It runs without any problems. I would like to test with 53V but my lab power supply max voltage is 62.2V.

TSDZ2 max pedal cadence
TSDZ2 max recommended RPM is 4100. I can't say what is the max pedal cadence but it should be easy to calculate if anyone knows what is the gear ratio between the motor and the pedal wheel -- can someone please help here?

Running TSDZ2 at 63V - 15S battery
15S * 4.2 (volts per each cell) = 63 volts.
I think it can be done but will be for sure on the limit edge, a the voltage capacitors of the motor controller are rated at 63V.

The advantage of running at higher voltage should be mainly for having more power, like with a 15S charged battery it should power the motor with 1134 watts (63 * 18 amps) as the speed can't be increased from the 4100 RPMs.

My notes about the video where I tested, running with our own developed OpenSource firmware, TSDZ2 running at 52.2V and 5600 RPMs:

I put my lab power supply at 62.2V, the max that it can gives. The firmware was controlling the current to not be higher than about 3 amps (power supply limit is 5 amps only).

Also the motor speed in ERPS was limited to 750 but I can see on the power supply (green LED) that after about 550 ERPS, the motor starts to asking to much current and being highly inefficient. This is because PWM frequency is at 16KHz and it will draw the FOC phase voltages wave signals with 28 points - any higher ERPS speed will mean lower number of points and that should distort the FOC voltage wave signal.
NOTE: the motor I used on the video is the 36V version.

The TSDZ2 motor has 8 pole pairs and this means that the RPM speed was:
- at recommended max limit of 550 ERPS: 4166 RPMS
- at the tested very inefficient limit of 750 ERPS (as seen on the video): 5600 RPMS

On my regular ebike, at 4000 RPMS I can get easily about 38km/h (but this speed depends on the bicycle gear ratio I choose to use).

[youtube]GzHg8fCl1Nc[/youtube]

 

[vscope]

I would suggest getting the 52v 750w motor. Another user has reported that the cadence is a bit higher than on the 48v engine so it apparently uses the same 48v motor winding. I would also go with a 14s battery. By running in the 58.8v - 42v range your max engine rpm (cadence) should be in the 100 (full battery) - 80 (depleted battery) range as you requested.

Has this higher cadence been confirmed on the 52v version?

The cadence appears to be a product of motor winding and voltage. From statements made earlier in this thread the 52v version is the same as a 48v version except it is flashed to allow the use of a higher voltage battery. I believe eyebyesickle clained the higher cadence with the 52v motor running at higher voltages. I have tested my 48v motor at different voltages and motor rpms are substantially higher when running my 48v motor at 56v as opposed to 48v. Apparently the more volts you give it the faster it will spin. I really want to remove the upper voltage limit in the firmware and try a 15s battery. Casainho claims the capacitors are rated to 63v which just happens to be the max voltage of a 15s battery.

that was my assumption also.
so if i want a bike thats faster (endspeed) with less torque its better to choose the 36v version with 13s and enable the 48V in the controller firmware. or is it going to be ineffecient? and better stay at 13s 48v version?

@casainho which version to you have 36v or 48v version?

i dont want to go higher than 13s.
i have a good source for cheap high quaility packs made in germany
https://enerprof.de/shop/akkus/ebike-und-pedelec-akkus/enerpower-softpack-48v-13s4p-2030ah-mit-bms-pedelec-akku-10x6-diy/?lang=en

 

[casainho]

Another test, to see the current controller working. Current was limited at about 3 amps and that a value of ADC = 6, as seen on green line. I hit the throttle fast and put it at max value, as we can see, the current jumps almost immediately to the limited value and keeps there, so this means the torque is constant and well controlled. And the speed, as we can see on red line, increases with an increasing curve because the wheel was loaded...

The purple line is the motor phase voltage the firmware apply, in a way to keep the current at the max limit.

I think the firmware for the motor controller is working very well. If anyone want to try (using a throttle only for now) but must use a fuse and a battery with a BMS.

 

[vscope]

I checked some images on the web.

Seems like gear ratio is:
outside 92/10
Inner wheel: 36/8
So all in all

92/10
36/8

9.2 * 4.5 = 41,4 / 1 ration
so 4000rpm / 41.4 = 96rpm cadence

so with the 48v motor i will reach 4000rpm/96rpm with full 13s battery and 2800rpm/68rpm (70%) with empty battery?
and with 36v motor i will reach 4000rpm/96rpm with full 13s battery and the same with empty battery?
is that correct?

 

[casainho]

Seems like gear ratio is:
outside 92/10
Inner wheel: 36/8
So all in all

92/10
36/8

9.2 * 4.5 = 41,4 / 1 ration
so 4000rpm / 41.4 = 96rpm cadence

Good work, thanks!!

And so 96RPM pedal cadence when the motor stops to assist (his max RPM and also 0 current/torque) but since we should count with some assist level, let's say 20% lower than max RPM, so maybe average max cadence RPM for TSDZ2 is 75 -- that's low, right??

 

[John and Cecil]

that was my assumption also.
so if i want a bike thats faster (endspeed) with less torque its better to choose the 36v version with 13s and enable the 48V in the controller firmware. or is it going to be ineffecient? and better stay at 13s 48v version?

@casainho which version to you have 36v or 48v version?

i dont want to go higher than 13s.
i have a good source for cheap high quaility packs made in germany
https://enerprof.de/shop/akkus/ebike-und-pedelec-akkus/enerpower-softpack-48v-13s4p-2030ah-mit-bms-pedelec-akku-10x6-diy/?lang=en

Yes and no. My concern would be burning out the 36v motor winding. I suspect it may not be able to handle as many watts as the 48v winding. Not many people have tried it, and there are no reports of it being able to handle high amounts of power for long term. If you are looking to do 15mph with lower watts maybe it would be ok, but 20-25mph is pushing the 48v motor to it's maximum. Is the 36v motor able to handle the same amount of power as the 48v motor (850w)? Can anyone answer this?

This is why I suggest running more voltage (and perhaps reducing amps slightly) through the 48v motor. We know the 48v motor winding can handle 850w or so, but how many watts can the 36v motor handle. I really think the 15s battery may be the ticket for this motor, perhaps slightly undercharged to increase battery longevity.

 

[casainho]

so with the 48v motor i will reach 4000rpm/96rpm with full 13s battery and 2800rpm/68rpm (70%) with empty battery?
and with 36v motor i will reach 4000rpm/96rpm with full 13s battery and the same with empty battery?
is that correct?

I don't know what may be better... But clearly the limitation is the motor max speed of 550 ERPs.

I think that our firmware can be developed to drive the motor with PWM of 20KHz and so would run at 550 * 1.25 ERPs = 687 ERPs; would increase cadence by 25%.

 

[Uturn]

My concern would be burning out the 36v motor winding.

You can set max amps in your display so the motor does not burn. Say it's a 350W 36V motor it will be specified for 9.7Amps. Now you run it at 48V, 7.5Amps will be enough to reach same Wattage.
However if open firmware can increase cadence by 25% that would be very interesting!

 

[John and Cecil]

My concern would be burning out the 36v motor winding.

You can set max amps in your display so the motor does not burn. Say it's a 350W 36V motor it will be specified for 9.7Amps. Now you run it at 48V, 7.5Amps will be enough to reach same Wattage.
However if open firmware can increase cadence by 25% that would be very interesting!

Yes but 350w is only half the power of the 48v motor. I believe the person that asked the question wants to ride around at 25mph. I don't think 350w is going to do that. I am lucky to get my 750w motor with 14s battery up to 20-22mph with light to moderate pedaling

It does seem like a nice alternative for people looking for less assist but higher cadence. If it will do 90 rpm at 36v then it should do close to 135 rpm at 56v. Coupled with Casianho's firmware in production that can limit the motor to a certain amount of watts throughout the rpm range it might work really well.

ps - That max amps in the displat is BS. It does not do anything, at least on the VLCD5 display. Changing that setting does absolutely nothing...

 

[vscope]

in my opinion the watt rating on these motors is just nonsense.
doesn't matter if its 250/350/500/750 watt motor, i think its completely the same motor/controller except of the different winding in the 36v / 48v version of the motor and the max voltage configuration in the controller software.
@casainho hope thats correct?

since the 36v motor just has less windings, the winding wire is/could be thicker.
so the 36v motor in theory could be able to push more wattage.

the 36v winding wont have a problem with 4000rpm since its rated for that.
however if you overdo it and push the motor to its limits that might bring troubles


i think i go the 36v 13s route. hack the controller max volt in software.
and hope that there will be a software reducing the max wattage when using the torque sensor just to be on the safe side

 

[John and Cecil]

Yes the engines and controllers are apparently the same but have different firmware settings and the 36v and 48v motors are wound differently.

If anyone has done any thermal (or extreme riding) testing of both the 36v and 48v electric motors I would love to know which winding would be the most reliable when being fed 750w of power. I agree that IF the 36v winding can handle as much power reliably as the 48v motor then running a 36v motor with a 13s battery may be the way to go!

 

[Rydon]

If anyone has done any thermal (or extreme riding) testing of both the 36v and 48v electric motors I would love to know which winding would be the most reliable when being fed 750w of power. I agree that IF the 36v winding can handle as much power reliably as the 48v motor then running a 36v motor with a 13s battery may be the way to go!

At a given voltage the tradeoff is speed vs torque/load. With fewer windings like the 36v motor you get speed but less torque. If you add a big load to the motor it will bog down and draw more power converting the excess power to heat. The 36v motor will go faster at a given voltage but the 48v motor will have more load capacity and will produce less heat at a given load. When climbing hills, riding into a headwind or carrying a lot of weight the 48v motor will generate less heat and be more efficient. At 48/52v if you live in a flat area the 36v motor will be faster. If you want that speed but have hills, wind or weight, make sure you have really low granny gear. You will go slow but the motor will get to spin faster and be more efficient and less likely to overheat the motor.

 

[Chalo]

I agree that IF the 36v winding can handle as much power reliably as the 48v motor then running a 36v motor with a 13s battery may be the way to go!

It seems like the opposite would be true for a pedal actuated system. My 48V BBS02, for example, has a free speed well in excess of what I can match with the pedals for more than a few seconds. Therefore, I use it with throttle only when I want it to get up to its best efficiency RPM. I would rather have a motor that performs well and efficiently within my comfortable pedaling cadence than one which makes more power at a speed I can't pedal along with. If my 48V system would run on 36V, I'd use it that way.

 

[vscope]

@rydon. thx for your detailed explanation. the 28km track to my office is completly flat an i ride without motor 30km/h average speed. my whole setup will be below 100kg.
so when i want to pedal in a high cadence and top speed should be above 40km/h i suppose the 36v will be better. motor assist should be in the 250 watt range. at 40km/h plus the aircooling of the motor shall also be good.

do we know the kv of the 48 and the 36v motor?

since then i could calc the cadence at a given volt....

 

[John and Cecil]

Yes I will stick to the 48v motor and consider bumping the voltage a bit if I want the best of both worlds, but I most definitely want the torque and heat resistance under load.

 

[casainho]

I wish more developers can join because there are a lot of good ideas to try!!

I think you guys should advance with all that different options, and the hardware parts are relatively cheap and easily available and that is a big advantage. Please go, try and sjare the results and we all will win!!

 

[Hillhater]

do we know the kv of the 48 and the 36v motor?

since then i could calc the cadence at a given volt....

no need to know the KV of the motors if you just want cadence.
We know that both motors have a maximum unloaded cadence of 96.
So each volt on a 36 v system alters the max cadence by 2.7
And on the 48 v unit is a straight 2 rpm per volt.
But be aware there are low battery voltage limits that cut this down as voltages reduce.
IE the 48 v set up cut cadence at 43v to about 30 or less !

 

[angusinalberta]

Casainho replied to my query about adding a datalogger:

Technically is very easy to implement that with our improved original firmware, because all of that data is already sent to the LCD3 by the serial line.

Anyway, I think that best idea is just to connect in parallel to the wire that comes from TSDZ2 motor controller to the LCD3, that that means no need to open or wire anything inside LCD3.

Fantastic! This becomes much easier than I imagined.
What is the baud rate parity etc of the stream?
3.3V or 5V?
What is the word size? 2 bytes?
Are there any control characters in the stream for synching? For example I'd expect something like:
cc A B C D E cc A B C D E... rather than A B C D E A B C D E...

Anything else I should know?
Cheers,
Angus

 

[vscope]

I think here we have all the information about 36-52v motors on this site:
https://www.eco-ebike.com/products/tsdz2vldc5?variant=2304362479625

overdrive 48v means that they use the 36v motor with 48V and change the eeprom settings on the controller.
overdrive 52v means that they use 48v motor with 52V and change the eeprom settings on the controller.

Maximum Torque: 36v = 80N.m / 48v Overdrive & 52v Overdrive = 90N.m / 48v & 52v = 100N.m (Power to conquer virtually
Pedal Cadence Assist: 36v & 48v = 90 RPM / 52v = 100 RPM / 48v Overdrive & 52v = 110 RPM / 52v Overdrive = 120 RPM

i just ordered the 36v motor and a STLinkV2.
lets go overdrive!

 

[dojrude]

52v overdrive has perked my interest a lot. Must have a look at that site.

Thanks for the info.

 

[casainho]

Casainho replied to my query about adding a datalogger:

Technically is very easy to implement that with our improved original firmware, because all of that data is already sent to the LCD3 by the serial line.

Anyway, I think that best idea is just to connect in parallel to the wire that comes from TSDZ2 motor controller to the LCD3, that that means no need to open or wire anything inside LCD3.

Fantastic! This becomes much easier than I imagined.
What is the baud rate parity etc of the stream?
3.3V or 5V?
What is the word size? 2 bytes?
Are there any control characters in the stream for synching? For example I'd expect something like:
cc A B C D E cc A B C D E... rather than A B C D E A B C D E...

Anything else I should know?

I can help you but I am only interested in doing it if you promise you will share some notes, photos and the Arduino code, on github as OpenSource.

 

[casainho]

Hmm....I downloaded the latest v3 LCD3 firmware (thanks!), flashed successfully, and then made sure to flash my TSDZ2 controller as follows below (I actually edited a value in the eeprom to work with 52V).

Same result (throttle and brake work, but display is all on (no backlight this time)): doesn't respond to signals, and no torque sensing (probably since assist is at zero)

I having the same issue as you!!

I have a new TSDZ2 and a new LCD3. I flashed them but they don't work.... I did debug the firmware on LCD and it is not receiving data from the motor controller.
I connected this LCD3 to my other EBike, were the other LCD3 works, and this new one just works -- so the LCD3 is ok, it is something with the motor controller... I wounder if they exchanged some wires on this new TSDZ2 I have...

 

[casainho]

Hmm....I downloaded the latest v3 LCD3 firmware (thanks!), flashed successfully, and then made sure to flash my TSDZ2 controller as follows below (I actually edited a value in the eeprom to work with 52V).

Same result (throttle and brake work, but display is all on (no backlight this time)): doesn't respond to signals, and no torque sensing (probably since assist is at zero)

I having the same issue as you!!

I have a new TSDZ2 and a new LCD3. I flashed them but they don't work.... I did debug the firmware on LCD and it is not receiving data from the motor controller.
I connected this LCD3 to my other EBike, were the other LCD3 works, and this new one just works -- so the LCD3 is ok, it is something with the motor controller... I wounder if they exchanged some wires on this new TSDZ2 I have...

Found the issue, on my notes, the LCD3 pins for TX and RX were exchanged, the correct are this ones (I will update my notes and put online):

KT-LCD3 | TSDZ2 LCD cable
• red wire | (P+) battery voltage
• blue wire | Vin
• black wire | GND ground
• green wire | UART TX motor controller
• yellow wire | UART RX motor controller

 

[jbalat]

Guys, please clarify in the queens english

The problem with this motor for me is the 90rpm. Its just so frigging annoying that you hit a brick wall and have to upshift to the next gear when your legs can spin much more.. Especially in a really low gear when you are only doing like 10 km/hr....
(My Bosch CX is far nicer to ride in this regard, it almost feels like you have a power band above 90rpm !!)

Anyway..
I have the 36v with 10s3p (30 batteries 3.5amp hrs each) max 42V

I want to reconfigure these for 15s2p which should still give me the same overall range as long as I don't overheat the motor

if 42v gives 90 rpm then 63v should give 135rpm right ?
Can the motor controller PWM handle this ? Sorry my bad but I couldnt figure out what ERPS's are.....

Casainho just to be clear are you saying your firmware only works with throttle ? since I don't have a throttle and don't intend to use one on this bike..