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General Category => Magic Pie & Smart Pie Discussions => Topic started by: Kauaikit on November 02, 2014, 06:47:16 PM

Title: Review of the Newest MP4
Post by: Kauaikit on November 02, 2014, 06:47:16 PM

Hello all….yes, I'm a new member and eager to try out the newest MP4 (sine-wave controller) on one of my older EVG PE (Police Edition) ebikes.

The 26" rim version, along with the dash and PAS setup is on it's way from China to S. CA.

Anyone have any advice or reviews of this hub yet for MAX performance?   

I've reviewed Gary's (Ca) excellent youtube video, though I'd like to know the upper most performance (60v) from this newest hub from GM.

Thanks.

Kit (kauaikit)

12/1/14

Installed the MP4 hub with grip throttle (factory out of thumb's) and LED display. Fairly straight forward. Installed two 22.2v/8ah (12s2p @ 50.4v/8ah) Nano tech batteries in the original EVG bike battery box.

It works as designed. Very quiet up to around 25mph.

I'm used to higher speeds, so have ordered a 14s5p Samsung 25r pack from China. I'll keep the voltage @60v and see if I can get the claimed 28mph level speed. Now working on installing the PAS to test on how that functions, though I've always been a throttle guy.

I've too ordered a second MP4 hub kit, though am having the Factory setup the sine wave controller for higher speed, though with less torque. This should be interesting to test.

KB

Title: Re: Review of the Newest MP4
Post by: GM Canada on December 12, 2014, 02:34:25 PM

Hello, I have not been in the forum for a while but trying to solve an issue for someone has brought me here so I thought I would read a few posts.

Thank you for your positive comments on my video.

First: Who is claiming it will go 28 MPH. This is something I have not seen.

Second: running it with a 60 volt battery is risky. Its not designed for that. Any spike over 60 volts will likely fry the controller instantly.

I'm not trying to be negative, just pointing out a reality from previous experience.

Gary

Title: Re: Review of the Newest MP4
Post by: Bikemad on December 12, 2014, 05:59:19 PM

Quote from: GM Canada on December 12, 2014, 02:34:25 PM

Running it with a 60 volt battery is risky. Its not designed for that. Any spike over 60 volts will likely fry the controller instantly.

I'm not trying to be negative, just pointing out a reality from previous experience.

Don't worry Gary, he's not using a 60V battery, he's planning on using a 14 cell LiPo pack, which is only 51.8V nominal and 58.8V maximum, that's only 0.4V higher than the 48V GM LiFePO₄ packs which are charged up to 58.4V.

Over the last five and a bit years I have run all of my GM hubmotors on a 14 cell LiPo pack without damaging any of the controllers. (Except for the tweaked controller that I managed to blow up after extracting over 97 Amps from it.) ::)

(http://www.arhservices.co.uk/GoldenMotor/MaxPower.GIF)

Alan
 

Title: Re: Review of the Newest MP4
Post by: Kauaikit on December 12, 2014, 07:22:43 PM

Hello Gary….my current interest in the latest Chinese manufactured Golden Motor MP4 is their upgrade to a internal sine-wave controller. I'm experienced with the now BK USA Wavecrest Tidalforce ebikes (2005) using the same tech though having a 7 phase motor. I have 8 of these bikes. These are over engineered NASA quality electric hubs. They originally used a 36v/8ah NiMH front battery hub source. Mine are upgraded to use 46.2v Lithium Poly battery packs, which is the max voltage allowed.

So, with a small investment I decided to try out a complete Golden Motor Magic Pie 4 "kit". As you know, it works well and is dead silent. A Chinese TF or even a poor mans BionX model D?!?   ;)

I've installed this first MP4 on an older EVG PE (Police edition) ebike (BK 2004) which I've retained the original controller to power the great front 35 watt front light, rear LED light, original left hand brake handle to power the rear LED brake light function, and too the horn!

Test riding this MP4 power ebike, a few days ago, with a charged 51.5v (NanoTech 22.2v/8ah x 2) battery pack got me a level speed of 27mph/43.2kph (195lbs). I using both the GM BAC-601 and a Cateye Enduro 8 bike computer. Getting 28mph/45kph from a charged 58.8v battery pack shouldn't be a problem. Currently I decided on having a 14s5p (58.8v/12.5ah) battery pack made up to fit into the original EVG ebike battery case, that slides in the side compartment. This shouldn't be an issue, since the MP4 sine wave controller has 63v caps installed. I've attempted to get the GM R&D department to update to higher voltage caps & Mosfets, but….

I'm eager to still install the PAS setup, as I just received my BB tool, and test the 1-5 settings.

I just received a second MP4 rear 26" "kit" that I had the GM R&D Department rewind for higher top end speed, though lower torque. I'll be testing this unit as soon as it stops raining here in S. California! I'm being told it will get an "off road" speed of 34mph/55kph with a 48v battery. Lets see? 

Gary, I've watched your videos and understand your a bit conservative in your speeds you like to ride. The last four years I've been riding street ebikes, I safely go to 31.5mph/50.4kph on level ground, though cruise around 25mph/40kph on my TF ebikes. I have a regular "cardio" 12 mile loop I ride 2/3 times a week. It's 6 miles up hill and then 6 miles downhill. And I've safely gone 40mph/64kph pedaling hard (53t-11t) on the Tidalforce bikes on a slight downhill.

Currently I have 31 ebikes in the collection and am looking for a low cost upgrade, and higher silent speeds, with the MP4 hubs. There is only one Company in Utah that can or will service the TF ebikes. The EVG ebikes use a heizmann brushed geared hub that is a bit noisy. Though I can go to 22mph/35.2kph using a charged 50.4v/8ah lithium battery pack. This is too slow for me. I have 17 of these ebikes.

I'd be curious to get your feedback on trying a 2wd dually MP4 setup for speed and performance on the street and even MTB trails.

Kit

Title: Re: Review of the Newest MP4
Post by: Kauaikit on December 12, 2014, 07:33:33 PM

Hello Allan….so, when are you going to attempt a 15s (63v) lithium battery pack, maybe only charge to 61.5/62v to test the limit of the MP controllers?  :o

I'm thinking the current MP4 sine wave controller should handle it just fine.

BTW, what level speeds are you getting on your MP ebikes using 14s?

Kit 

Title: Re: Review of the Newest MP4
Post by: Bikemad on December 13, 2014, 02:01:10 PM

Quote from: Kauaikit on December 12, 2014, 07:33:33 PM

Hello Allan….so, when are you going to attempt a 15s (63v) lithium battery pack, maybe only charge to 61.5/62v to test the limit of the MP controllers?  :o

I'm thinking the current MP4 sine wave controller should handle it just fine.

BTW, what level speeds are you getting on your MP ebikes using 14s?

Hi Kit,

I have tried 15s in the past but the voltage was too high for the controller to work. When the voltage eventually dropped below the High Voltage Limit  on the controller (below 60.5V if I remember correctly) the motor would work fine.

Unfortunately my last remaining 14s LiPo pack is getting on a bit and the packs are starting to swell, but I can't really complain as they had a lot of use during the last 5 years. I now get a large voltage drop on some cells under load and the pack is therefore unable to deliver the high current that it used to supply. 

The majority of my rides are purely for walking the dog through grass fields and bumpy lanes, my dog is now over eight years old, so I rarely exceed 15 mph.

(http://www.arhservices.co.uk/GoldenMotor/heidi.JPG)

As I live in a very hilly area, torque is far more important to me than top speed.

My rides are typically two or three miles long, so I tend to use a small lightweight 8s LiPo pack comprising of two 4s hard case Turnigy 5000mA packs in series, but even these are beginning to bulge slightly.
I managed to pop one of the hard case packs last week during one of my wheelie sessions while the dog.
I noticed the power had dropped significantly and when I removed pack for charging, I found this very disturbing sight:

(http://www.arhservices.co.uk/GoldenMotor/LiPo/2014-12-08233338_zps11ad7e15.JPG)

(http://www.arhservices.co.uk/GoldenMotor/LiPo/2014-12-08233706_zps3f6131d2.JPG)

(http://www.arhservices.co.uk/GoldenMotor/LiPo/2014-12-09000555_zps85191b17.JPG)

(http://www.arhservices.co.uk/GoldenMotor/LiPo/2014-12-09001403_zpsf83ad94a.JPG)

And this is what it now looks like after undergoing some experimental LiPo-suction:

(http://www.arhservices.co.uk/GoldenMotor/LiPo/2014-12-09171206_zpsadfaa434.JPG)

(http://www.arhservices.co.uk/GoldenMotor/LiPo/2014-12-09171416_zpsf4ae226a.JPG)

(http://www.arhservices.co.uk/GoldenMotor/LiPo/2014-12-09171606_zpsd25d5336.JPG)

These hard case packs are only just 2½ years old and have never been overloaded or more than 80% discharged, yet all four of the packs that I have are now bulging. 

I haven't tried 15s on the MP4, perhaps I will give it a go one day just to see what happens.

Alan
 

Title: Re: Review of the Newest MP4
Post by: GM Canada on December 14, 2014, 05:41:59 AM

Quote from: Kauaikit on December 12, 2014, 07:22:43 PM

I'd be curious to get your feedback on trying a 2wd dually MP4 setup for speed and performance on the street and even MTB trails.

Kit

If you have followed my posts and videos you can see I have built many two wheel drives, even a three wheel drive.

I have thought about two wheel drive mp4 but to be honest it really does not seem necessary. The power is far more than I need and I have zero fear of controller failure. I do ride a long isolated trail home from work and I can actually be miles from the nearest road at times so I always liked the confidence of two motors if one failed. But the reliability factor has increased by leaps and bounds and Im really enjoying that fact. The only Issue I have is I stocked up on a lot of mp4 controllers at release time just incase and now they just sit there.

Gary

Title: Re: Review of the Newest MP4
Post by: GM Canada on December 14, 2014, 05:43:18 AM

Awesome picture of your dog!

Title: Re: Review of the Newest MP4
Post by: Bikemad on December 14, 2014, 12:45:11 PM

Quote from: GM Canada on December 14, 2014, 05:43:18 AM

Awesome picture of your dog!

That's because she's an awesome dog!  ;)

Unfortunately she doesn't always stay quite that clean, as she cannot resist wallowing in muddy puddles:

(http://www.arhservices.co.uk/GoldenMotor/image-1332708318-V_zps283ef891.JPG)


Alan
 

Title: Re: Review of the Newest MP4
Post by: Kauaikit on December 14, 2014, 06:39:57 PM

Alan…I've been using the HK Nano Tech 22.2v/8ah & 18.5v/8ah batteries for years on the Tidalforce ebikes. The engineers @ Wavecrest Labs decided to be very conservative and max the voltage @ 46.2v. So I combine one 22.2v & one 18.5v batteries in series for a 46.2v/8ah (charged) battery, then parallel a similar pack for a 46.2v/16ah 10lb brick. Works great, though I tend to puff a cell or two within 6 months. My level performance is 31.5mph/50.4kph (195lbs) level, and 37+mph/59.2kph on a slight downhill pedaling (53t-11t). The Tidalforce 7 phase internal sine wave controller hubs are amp hogs!  :-)

I've been using 2 of the 22.2v/8ah batteries for a 50.4v/8ah battery to test the MP4's. I'm waiting for my 14s5p Samsung 18650 cell pack to be finished, though I thought of trying a 15s/5p pack but only charge to 60v (4.0 cell), instead of the max 63v, to eek out one more volt. Which too is why I'm curious on the max voltage the newest MP4 sine wave controller will take. Which you say is 60.5v, right?

My goal is to match the American manufactured TF performance with a lower cost Chinese substitute. :-)

I'll be testing my second MP4 (HS "CA Special") today, though it's been setup by Golden Motor for higher speed performance but expected lower torque (50nm vs 70nm).

Would you be curious on the test results, though it's only using a 50.4/8ah battery pack?

Kit
S.CA

Title: Re: Review of the Newest MP4
Post by: Bikemad on December 15, 2014, 01:36:40 AM

Quote from: Kauaikit on December 14, 2014, 06:39:57 PM

Which too is why I'm curious on the max voltage the newest MP4 sine wave controller will take. Which you say is 60.5v, right?

No, the 60.5V limit was on the earlier controllers (MPII and MPIII).

The MP4 vector controller can have the overvoltage protection set using the USB lead and it can be programmed for up to 65V maximum, but the default setting is 62V for the 48V battery.
The two large capacitors are marked 80V, one of the smaller ones is rated 63V and two others are rated 25V. But as I cannot access the tracks on the PCB, I don't know whether the smaller capacitors are subjected to full battery voltage or not. :-\

I'm guessing it may be feasible to set the maximum to 65V and then use a 15S LiPo pack fully charged to 63V without experiencing any problems, but I haven't tried it yet. ;)

It's a pity that the Nominal voltage can only be set to 24V, 36V or 48V, as it would be nice to be able to set it correctly for different LiPo packs (29.6V for 8s and 51.8V for 14S etc.).

Quote from: Kauaikit on December 14, 2014, 06:39:57 PM

I'll be testing my second MP4 (HS "CA Special") today, though it's been setup by Golden Motor for higher speed performance but expected lower torque (50nm vs 70nm).

Would you be curious on the test results, though it's only using a 50.4/8ah battery pack?

It would good to know how much faster the MP4 is with the modified windings, which I guess has been reconfigured as delta instead of star (Y).

I wonder how long it will be before we start seeing 12 or 24FET controllers connected to motors via 6 phase wires which would be able to automatically switch between Delta and Star (electronically) dependant upon the speed and load of the motor. This combined with a built in high power variable voltage step-up inverter would allow much higher top speeds to be achieved using lower voltage batteries.
(http://www.arhservices.co.uk/GoldenMotor/emoticons/thinking.GIF)

Alan
 

Title: Re: Review of the Newest MP4
Post by: Kauaikit on December 15, 2014, 02:15:15 AM

Alan…please give me an email address, as my iPhone tends to take photos too big to attach here. You may enjoy reading todays results.

Kit
kauaikit@earthlink.net

Title: Re: Review of the Newest MP4
Post by: Bikemad on December 15, 2014, 10:08:44 AM

My email address should be underneath my avatar, but I have just PM'd you just in case you can't see it on your iPhone.

Is it by any chance a photo of a speeding ticket?

Alan
 

Title: Re: Review of the Newest MP4
Post by: Morgen 3Eman on December 15, 2014, 07:35:51 PM

Hi Folks,

Damn, Alan, that winding switching idea is a great idea.  It effectively gives the motor an equivalent of a two speed transmission, with higher torque in one setup, and higher speed on the other.  GM would be crazy not to use this scheme. I gotta draw out a schematic for doing the switching. 

Brilliant work, dude.

TTFN,
Dennis

Title: Re: Review of the Newest MP4
Post by: Supchrgamx on December 15, 2014, 10:30:20 PM

sounds like laminations more than y delta

Laurence

Title: Re: Review of the Newest MP4
Post by: Morgen 3Eman on December 16, 2014, 12:26:43 AM

Hi Lawrence,

I have no idea how laminations effect motor speed and torque.  How about making me smarter by explaining it, or pointing us to some web site that might explain it.

TTFN,
Dennis
(the inquisitive old fart)

Title: Re: Review of the Newest MP4
Post by: Supchrgamx on December 16, 2014, 06:00:11 AM

trouble is I read to much
this may or may not be true , but this is what I have read

hi kv or low turn count is faster

low kv  or high turn count  is slower but more torque
this is the motor that you will want for a y -delta motor

lower pole count is faster

thinner laminates are quicker
other motors use 50mm 35mm and 20mm

more amp = more torque
more voltage = higher speeds

y-delta has 2 problems
if you loose 1 phase of three in delta, the wheel locks up
when you are in y the winding are in series , you have a break any where, it kills the power
delta you have 2 winding in series paralleled with the third winding, if you loose 1 winding the power can still go through the other wjnding
so if your controller screws up or you cook a winding in delta,  at high speed ,watch out
but you say, I wont put enough current through my motor to cook my controller or motor to be safe
when you go delta  the current increases by 1.73 so your controller and bms has to be able to handle that extra current
but you say , no problem I will increase my bms and controller to handle the extra current
so you have done all of this and are ready to try this y delta thing
so lets say that when you are in y ,your top speed is 50 kmh
you switch it to delta, your current increases by 1.73 and your speed should increase  by 1.73 ,but because of wind drag you only increase by 1.5 to a speed  of 75 kmh
but your controller doesn't like switching winding under full load, no problem , when you switch you now have a throttle kill that interrupts the throttle for 40 milliseconds to allow the relays to switch and then allows full power again
so you have taken care of all of this and think , what could go wrong
 so now you have a controller that will handle higher current for the delta
back to my story
so you are flying down the road  at 75 kmh thinking this is great
but at some point you need to slow down, so you release the throttle  and you coast abit
and then ,not even thinking you switch back to y
if you do it below 50 kmh every thing is fine and you live to do it again
if you do it above 50 kmh the back emf created will fry your fets and over the handle bars you go
so now you need something to prevent it switching back to y until you reach the lower speed or
you increase the controller or fets to handle the higher voltage
so if you have a higher current and voltage controller you might as well feed it with more battery and leave it in y

correct me if im wrong

Laurence

Title: Re: Review of the Newest MP4
Post by: Morgen 3Eman on December 16, 2014, 06:38:16 AM

Hi Laurance,

I want to apologize in advance for being a terrible person.  I am not questioning you to hurt your feelings, but to learn.  An Aussie called me a bully a while back, and wanted me kicked off the board, and I am still stigmatized by that. 

So…….

I agree with much of what you say, but the question I had was : how do laminations affect motor torque and speed?  You say thinner laminations  are quicker, and that other motors use 50mm 35 mm and 20 mm:  So Why?  Why are they quicker? and what does GM use?  (PS: 20 mm laminations are way thicker than I have ever seen.  I have never measured them, but I would guess most of the motor laminations I have seen were a vey few tenths of mm thick)

That being said, regarding loss of a winding; in my experience, it won't matter which way the motor is connected: you are screwed.

TTFN,
Dennis

 

Title: Re: Review of the Newest MP4
Post by: Bikemad on December 16, 2014, 12:33:35 PM

Dennis, I think Laurence was talking about the overall thickness of the stator core, not the individual thickness of each steel laminate.

(http://www.arhservices.co.uk/GoldenMotor/P7291341_zps8edae824.JPG)

The stator core is constructed from laminated steel plates instead of a single solid piece of steel (~35 layers on the Magic Pie), as it greatly increases the stator's efficiency by increasing the resistance and surface area which reduces unwanted heat generation and loss of energy by reducing the induced eddy currents within the steel core.

Although the thickness of the individual laminations will have an effect on the efficiency of the motor, I'm not really sure how much it would actually affect the speed of the motor (rpm/volt).

If you use the same gauge copper wire and the same number of turns on each coil, the total length of the windings will be much less on a thinner stator than it would be on a wide stator, therefore the resistance of the windings will also be lower on the thinner stator allowing more current to flow from the same applied voltage.
Shorter windings and higher current usually results in a higher motor speed, which is basically why the speed increases when you switch from star to Delta:

(http://www.arhservices.co.uk/GoldenMotor/DeltaStarswitching.JPG) (http://goldenmotor.com/SMF/index.php?topic=2830.msg18417#msg18417)

Alan
 

Title: Re: Review of the Newest MP4
Post by: Morgen 3Eman on December 17, 2014, 12:49:43 AM

Hi Folks,

I understood how the wiring affects speed and torque, and how lamination thickness affects I(2)R loss, but didn't twig to the core thickness affecting the winding length and turns and thus the speed.   Thanks. 

By the way, electronically switching the connections  (VS relay) is a bit more complex than I first thought.  I didn't immediately consider the bidirectional circulating currents.  I must be getting too old to think.  I still think you have a great idea… Using Laurences number of 1.73, that is a nice ratio for a two speed tranny.

TTFN,
Dennis

Title: Re: Review of the Newest MP4
Post by: Morgen 3Eman on December 17, 2014, 12:53:10 AM

Hi Folks,

It turns out the that old General Motors PowerGlide two speed automatics had speed ratios of 1.76 or 1.82!  I'm telling you this is a great idea.

Dennis

Title: Re: Review of the Newest MP4
Post by: Supchrgamx on December 17, 2014, 07:40:01 AM

bad eddie currents
no offence taken
just threw it all out there to see the response

Laurence

Title: Re: Review of the Newest MP4
Post by: Supchrgamx on December 17, 2014, 06:48:37 PM

not saying it  cant be done
I have built my stuff with existing components and just modify what out there  to make it work for me
simple and fast
some times it work better than expected and some times not so good
so if I had a r and d department I would build a controller that would shut down on the up shift for a second and then not let it shift back down until the motor reaches a safe speed and if it is a issue ,monitor all phases for balance and if a hazard rears its ugly head shut the controller down
some where I saw a diagram that they use 3 more fets to do the y delta switch on top of the 6 fets for just y
and that is a standard ac motor winding switch and that's what im use to
but
here comes the what if
the y has two winding in series and im ok with that
the delta has two winding in series paralleled with the third one
and that is standard for a ac motor ,but do you need to do this
why cant you switch one winding at a time in a delta  set and do not feed the winding in series anything
I don't know if the series winding in delta contribute any power to the motor or just add losses
welcome to the inside of my head
enlighten me with your smarts

Laurence

Title: Re: Review of the Newest MP4
Post by: Morgen 3Eman on December 17, 2014, 11:51:09 PM

Hi Laurence

Your question about using only two windings beats the hell out of me!  But I do know you will have to do something with the third winding, as there will be a current induced in it.

TTFN,
Dennis

Title: Re: Review of the Newest MP4
Post by: Kauaikit on December 18, 2014, 02:38:23 AM

So…I asked what was changed from their newest MP4 offering to this High Speed California Special (HS CA SPL) MP4.1 version that I had special ordered and was told…"we changed the winding, and resistance and inductance of contoller".  That was it. :o

Is anyone curious what the performance was achieved with this one off HS MP4.1 compared to the standard MP4 hub?

Kit
S.CA USA

Title: Re: Review of the Newest MP4
Post by: Supchrgamx on December 18, 2014, 04:59:38 AM

sorry for hi jacking the thread
kit I would love to know
dennis they have one winding in y that's not used when the other two windings are run in series, why cant they not use two windings in delta and just do phase a -b-c

Title: Re: Review of the Newest MP4
Post by: Kauaikit on December 18, 2014, 07:23:43 AM

Ok….I'm only using 2 HK 18.5v/8ah Nano Tech batteries (50.4v/8ah). Way below the max levels allowed.

My level speed on this special order High Speed California Special MP4.1 (HS CA SPL MP4.1) is 32mph/51.2kph (195lbs), and on a slight downhill pedaling (46t-11t) I'm getting 37mph/59.2kph. And an average of 22.4mph/35.9kph for a 12 mile/19.2km ride!

WOW….this performance matches my Tidalforce bikes, though the MP4's don't have the same torque. Though I need a 16ah battery for the same 12mile/19.2km distance on the TF bikes.

I'm waiting on my 15s5p Samsung 25r battery pack to come from China…then I'm have a real top speed and distance from a 12.5ah battery pack that fits inside the original EVG ebike battery case!

I'll be working on the PAS setup to see if I can get it to work for me, though I tend to like the thumb throttle.

After the Xmas holidays, I'll be ordering 2/3 more of these HS MP4 "kits"….they work.

What are your speeds or performance numbers on your MP4's?

Title: Re: Review of the Newest MP4
Post by: Morgen 3Eman on December 18, 2014, 07:22:08 PM

Hi Laurence,

The third Y winding is not energized  directly by current from the battery thru the H-switch, but the magnetic fields will induce a current into that coil.  There are diodes in the H-switch drivers that effectiively ground that end of the coil, while the other end is always connected to ground.  That keeps the voltage across the coil from going really, really high and damaging things. 

Does that make any sense?

TTFN,
Dennis

Title: Re: Review of the Newest MP4
Post by: Supchrgamx on December 19, 2014, 03:25:23 AM

oh now, we are going to add rules are we
h switch  ,you know ,its been 30 yrs since I've  done electronics
1 winding - motor , 2 windings generator , got it
flying diode or what ever you call it ,got it
I feel like your toying with me dennis
I don't want this to be this, didn't work out version

Title: Re: Review of the Newest MP4
Post by: Supchrgamx on December 19, 2014, 03:46:32 AM

hi Kit

300 lbs combined weight 15 ah @ 48v batt 58v charged I think
26 rim 235 tires I can do 48 kmh peddling and go 48km on one charge not peddling
and im pulling 16 amp to do it
I can ride for 6 hrs at 22kmh average but,  that's stop and go riding in the river valley
or at least I use to be able to, until 2 feet of snow
that would be awesome to be able to travel at town speed
we have pot holes in the road that would swallow a  bike

laurence

Title: Re: Review of the Newest MP4
Post by: Morgen 3Eman on December 19, 2014, 04:42:31 AM

Sorry I annoyed you.  Didn't mean to.  Thought we were having a discussion.   You from OZ?

TTFN,
Dennis

Title: Re: Review of the Newest MP4
Post by: Supchrgamx on December 19, 2014, 05:16:43 AM

didnt annoyed me.    we are having a discussion.   Canada
trying to make lite conversation and failing badly
didn't think of induced voltage , just a little rusty , I guess
need to draw a picture to get a handle on this
and if I remember right if you short the winding it becomes a brake

Laurence

Title: Re: Review of the Newest MP4
Post by: GM Canada on December 19, 2014, 07:01:11 AM

Quote from: Morgen 3Eman on December 16, 2014, 06:38:16 AM

Hi Laurance,

I want to apologize in advance for being a terrible person.  I am not questioning you to hurt your feelings, but to learn.  An Aussie called me a bully a while back, and wanted me kicked off the board, and I am still stigmatized by that. 

So…….

hi Dennis,

I have seen you post this more than once. I do recal when this happened, but what was actually said I do not. It hardly matters though. I can say I have had simular situations. I hammer out a lot of email some days and I guess they don't sound friendly at times. I usually give people quick answers or links to the questions that are asked the most like this 4 answer reponce to four questions

1- yes
2- no
3- read this http://www.goldenmotor.ca/FAQ/questions.php?questionid=126
4- have no experience with that try the forum www.goldenmotor.com/SMF

Enjoy the ride
Gary

Most people just accept the answers, some ask more questions and the occasional comment about being so breif.

I realize your posts are nothing like this but I have found inserting a few smileys in makes a differnce in the response. Like...

1- yes :)
2- No :(
3- read this http://www.goldenmotor.ca/FAQ/questions.php?questionid=126  ;)
4- have no experience with that try the forum www.goldenmotor.com/SMF  :o

Enjoy the ride
Gary

I know bad smileys and your posts are nothing like how I answer email. But still tossing in a smiley every now and then never hurts. Just think about your wife and the difference in how you feel when she looks at you with a smile as opposed to a cold stare.

Just my two cents, don't mean to offend. Just making an observation.  8)

Gary

Title: Re: Review of the Newest MP4
Post by: Morgen 3Eman on December 19, 2014, 06:59:00 PM

Hi Gary,

I have to tell you that I do not understand how putting a smiley face on it will change the fact that a changing magnetic field will induce a current in a conductor, but if you think it will help, I'll try it.:) :D

Thanks for the suggestion. :)

TTFN,
Dennis

Title: Running the MP4 on a 15 cell LiPo pack (63 Volts)
Post by: Bikemad on December 20, 2014, 03:52:58 PM

Quote from: Bikemad on December 15, 2014, 01:36:40 AM

The MP4 vector controller can have the overvoltage protection set using the USB lead and it can be programmed for up to 65V maximum, but the default setting is 62V for the 48V battery.
The two large capacitors are marked 80V, one of the smaller ones is rated 63V and two others are rated 25V. But as I cannot access the tracks on the PCB, I don't know whether the smaller capacitors are subjected to full battery voltage or not. :-\

I'm guessing it may be feasible to set the maximum to 65V and then use a 15S LiPo pack fully charged to 63V without experiencing any problems, but I haven't tried it yet. ;)

Here's an update:
I have just tried running my latest MP4 controller on 15 x 5Ah LiPo cells and I can now confirm that it works.
 (http://www.arhservices.co.uk/GoldenMotor/emoticons/6_small.GIF)
I set the controller's overvoltage protection to 63V (15 cells @ 4.2V) and the 15s battery voltage was reading 62.53V.
Maximum current reading was 30.28 Amps, Maximum Wattage was 1565.9, but as the LiPo packs I used are very old and weak there was a huge voltage drop of ~15 Volts at full power (which is almost 25%!)  :o

As my new LiPo pack only drops ~5% with a 45 Amp load, I would expect a good 15 cell LiPo to drop to around 58V, which should produce 1756 watts of power at the same 30.28 Amps. If the shunt on the vector controllers could be modified to allow ~50 Amps (like I did with my current MPII controller) the torque would increase by 65% and the maximum power should also increase to around 2900 Watts!! ;D

Fortunately for me, the BAC-601 also seems to have survived the higher voltage, and here is the maximum unloaded wheel speed achieved by applying full throttle with the wheel raised off the ground:

(http://www.arhservices.co.uk/GoldenMotor/MP4Unloadedspeed625V_zpsfe2e5051.JPG)

I didn't have enough time to carry out a decent long test, but at least I have confirmed the MP4 controller can be used with a battery voltage in excess of 60V, whereas the MPIII controller cannot. ;)   

Alan

P.S. I'm not sure if I have used enough smilies to keep Gary happy, so here are a few more just in case! ;) ::)

(http://www.arhservices.co.uk/GoldenMotor/emoticons/bike.GIF)    (http://www.arhservices.co.uk/GoldenMotor/emoticons/bike.GIF)       (http://www.arhservices.co.uk/GoldenMotor/emoticons/bike.GIF)    (http://www.arhservices.co.uk/GoldenMotor/emoticons/emoticon_on_bike.GIF)  (http://www.arhservices.co.uk/GoldenMotor/emoticons/bike.GIF)            (http://www.arhservices.co.uk/GoldenMotor/emoticons/bike.GIF)    (http://www.arhservices.co.uk/GoldenMotor/emoticons/bike.GIF)  (http://www.arhservices.co.uk/GoldenMotor/emoticons/emoticon_on_bike.GIF)           (http://www.arhservices.co.uk/GoldenMotor/emoticons/bike.GIF) (http://www.arhservices.co.uk/GoldenMotor/emoticons/emoticon_on_bike.GIF)  (http://www.arhservices.co.uk/GoldenMotor/emoticons/bike.GIF) (http://www.arhservices.co.uk/GoldenMotor/emoticons/emoticon_on_bike.GIF)  (http://www.arhservices.co.uk/GoldenMotor/emoticons/bike.GIF)           (http://www.arhservices.co.uk/GoldenMotor/emoticons/bike.GIF)  (http://www.arhservices.co.uk/GoldenMotor/emoticons/emoticon_on_bike.GIF) (http://www.arhservices.co.uk/GoldenMotor/emoticons/bike.GIF)    (http://www.arhservices.co.uk/GoldenMotor/emoticons/bike.GIF)   (http://www.arhservices.co.uk/GoldenMotor/emoticons/bike.GIF) (http://www.arhservices.co.uk/GoldenMotor/emoticons/emoticon_on_bike.GIF)   

Title: Re: Review of the Newest MP4
Post by: Morgen 3Eman on December 20, 2014, 07:03:23 PM

Thanks for the laugh, Alan:)

It brought a smile to my face and page:)

The 80 Volt cap is most likely for bulk filtering the supply voltage, so it should survive on 63V, but I would be very scared as the voltage supply went much more than 65V-70V.   I have no idea what the 63 V and 25 volt rated caps are for.  Inductive phase angle correction? Probably not. :)  Perhaps they have a linear power supply for some internal function? :)   Good engineering practice says they are being subject to around 45V and 18V.  :) Perhaps there are some opamp circuits running plus and minus 15VDC?  That would be a typical usage for the 25V caps.  Just a guess, again, but zero crossing detectors would be pretty handy to have for triggering functions. :)
 
Ya gotta love Gary, eh?:)  He must be fun in a pub for a bevvie.:)

Have a nice day 8)
Dennis

Title: Re: Review of the Newest MP4
Post by: Kauaikit on December 20, 2014, 10:50:00 PM

Thanks Alan...good to know a 15s5p pack will work! And I will report my results on this end with both MP4's @ 63v.

So, do I work GM, again, to get their R&D department to up the amps to 50 on the MP4 controller....for controlled testing of course?!?

Philip @ GM has already to told me, "the MP4 is fast enough" when I requested my last special order HS MP4!   >:(

I'm fine with the torque on the standard MP4, and the top speed of the HS MP4...now, I just want both for this "poor mans BionX model D and Tidalforce X version ebikes".

Kit
S.CA USA

Title: Re: Review of the Newest MP4
Post by: Bikemad on December 21, 2014, 12:57:39 AM

Quote from: Kauaikit on December 20, 2014, 10:50:00 PM

I'm fine with the torque on the standard MP4, and the top speed of the HS MP4...now, I just want both for this "poor mans BionX model D and Tidalforce X version ebikes".

Perhaps you should build a dual Pie bike with a high speed MP4 on the front and a standard MP4 on the rear, this would give you the best of both.
More torque and more speed than you have at the moment, and the slower motor would only begin to hold you back when you try to exceed 37 mph!

Alan
 

Title: Re: Review of the Newest MP4
Post by: Kauaikit on December 21, 2014, 05:55:37 PM

Alan....that was my first initial plan with the newest MP4, but was told by GM that many people were falling @ higher speeds with a dually setup. Maybe it was just with the MPIII?

So, I was concerned about cogging on the front hub @ higher speed, but your suggestion sounds like something worth testing.  ::)

BTW, have you done a level speed test @ 63v, and what level speed (lbs) are you getting on your standard MP4?

Kit

Title: Re: Review of the Newest MP4
Post by: Bikemad on December 21, 2014, 06:44:12 PM

Hi Kit,

I haven't tested it flat out on the road as the legal limit over here is only 15 mph and the maximum permitted power is a mere 200 Watts!!

My bike that has the MP4 fitted is a little bit conspicuous and it tends to stand out like a sore thumb rather than blend in with other cyclists:

(http://www.arhservices.co.uk/GoldenMotor/MP4/P8162417_zps00b972e3.JPG)

So I would definitely be asking for trouble riding it fast on public roads.

With my usual 8 cell LiPo pack I don't go fast enough to draw attention to the motor's power, so I am hopefully not going to get stopped by the police, and as the majority of my riding is done off-road, I am not overly concerned. ;)

Alan
 

Title: Re: Review of the Newest MP4
Post by: Kauaikit on December 21, 2014, 08:33:34 PM

Alan....what a shame, when non bike riders actually make laws that must be obeyed by actual bike riders. The Euro and Canadian ebike laws are just silly! Even the spandex riders can go 30+mph/48kph on leg power alone.

Bike riders, in the USA, are generally still under the radar. I've never been stopped or questioned in the last 4 years that I've focused on only riding electric street bikes. I retired from years of hard core mountain biking after knee surgery. So, the street riding still gives me my cardio workouts. And it's also fun to compete and test different ebikes and their setups on my regular 12mi/19.2km course. And of course I'm always on the lookout to race these spandex riders.

I've not yet setup an electric offroad mountain bike.

My regular gym drive to vehicles is either a '06 Harley Road Glide or one of two '68 Ford Cobra Jet Mustang GT 428ci fastbacks. I like American muscle, hence my initial ebike interest in the Wavecrest Tidalforce bikes for street riding.

Kit

Title: Re: Review of the Newest MP4
Post by: Supchrgamx on December 22, 2014, 01:05:45 AM

what do you know about Canadian law kit

dennis, we still talking?
I knew you had dry humour, made me laugh

Laurence

Title: Re: Review of the Newest MP4
Post by: Morgen 3Eman on December 22, 2014, 05:59:05 PM

Hi Laurence

It is surprisingly hard to  make me shut up:)  What ya got?

Have a nice day 8)
Dennis

Title: Re: Review of the Newest MP4
Post by: Supchrgamx on December 24, 2014, 01:22:34 AM

some where on the web

And then there is the issue of eddy-current losses. Eddy currents are too complex to fully explain here, just know that for very high RPMs, you need thinner laminations and a lower pole-count, or…you will reach a certain RPM (different for each motor design) where there is a sudden and seemingly unexplainable increase of heat.

One example of this is the popular MAC geared hub motor from em3ev.com. The standard model performs well at 36V and 48V. But when builders began using it at 60V and 72V (which makes it spin faster), some of them would encounter heat spikes when they were at their highest RPMs (caused by eddy currents and a high switching frequency). Paul at em3ev.com now provides the option of an upgraded MAC with thinner laminations and a factory-installed heat sensor for builders who want to run higher RPMs.
A stator core must be made from some type of steel, but they are not solid blocks. The stator is made from many thin slices (called laminations) that are stacked together to make the final shape. Laminations that are 0.50mm thick are common and very affordable (due to the high volume of production). The thinner (and slightly more expensive) 0.35mm thick lams are the next common upgrade. The High-efficiency Joby motor (no longer made) is capable of 10,000-RPM’s, and it uses 0.20mm thick lams.

High-RPM laminations also have a higher content of silicon in their steel. I don’t know why that helps them run cooler…but it does.

Laurence