GoldenMotor.com Forum
General Category => General Discussions => Topic started by: Mordaz on September 13, 2007, 09:17:08 PM
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Any ideas on how to implement such function with a regen controller?
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Switching supply power to the controller on and off is the only way I know. The new, new regenerative controller is expected to allow user specification of freewheel width at both ends and in the middle but not a random or arbitrary point of freewheel, so again a supply power switch is needed.
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When can we expect the new regen controller to be available (36V Or 48V) and how we can tell the difference from the old and the new versions? ???
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I have just received the regen controller but have not tried it yet. How can I tell the new, new model from the old version?
With the regular controller I can pedal along with the motor and get faster. But the regen function is really great when going downhill. That's why I think a freewheel/regen mode switch would come in handy.
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That is exactly what I am looking for !! Here in SJ valley there aren't very many hills but plenty of silly drivers who don't stop at stop signs so the regen/brake will come in very handy. Oh, mordaz, was that 48V or 36v??
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Sorry guys, I hate to report that I have not received either the 30 kits, the wheel chair sample or the new, new regen controller yet. I can report that today I have received six samples of Allegro's new Three Phase Power MOSFET Controller
which I will hopefully be testing over the next few weeks.
...not suitable for hub motor regenerative commutation, sorry.
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What battery chemistries does the allegro controller support? SLA LiPo, LiFeP04, Nimh. ??
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Since it is programmable I would say all chemistries are capable of support by the OEM but let me check further and see if Allegro or one of its OEM's specifically state or do this. Adaptation to battery chemistries is definitely not a built-in function of the commutation chip.
Also, it appears that the BRAKE function of both Allegro commutation chips does not support regeneration.
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Since it is programmable I would say all chemistries are capable of support by the OEM but let me check further and see if Allegro or one of its OEM's specifically state or do this. Adaptation to battery chemistries is definitely not a built-in function of the commutation chip.
Also, it appears that the BRAKE function of both Allegro commutation chips does not support regeneration.
A 3PH bridge into a boost converter would effect regen braking.
Dan
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As I understand it when the BRAKE function is not selected and no power is applied the MOSFETS are open and simply allow the motor to spindown whereas when the BRAKE function is selected all MOSFETs are shorted. Thus you have freewheel from the chip when the BRAKE input is not active. Although you can insert diodes across the MOSFET pins and create a 3ph bridge rectifier when the BRAKE function is active there is no provision on the chip for PWM to control the level of regen, so that the instant you release the throttle and switch to regen you get 100% regen instead of a throttled amount. This is why the current Golden regen controllers use a microcontroller and software for everything instead of a commutation chip. I'm looking for a commutation chip that has PWM braking, and hence PWM regen built-in.
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As I understand it when the BRAKE function is not selected and no power is applied the MOSFETS are open and simply allow the motor to spindown whereas when the BRAKE function is selected all MOSFETs are shorted. Thus you have freewheel from the chip when the BRAKE input is not active. Although you can insert diodes across the MOSFET pins and create a 3ph bridge rectifier when the BRAKE function is active there is no provision on the chip for PWM to control the level of regen, so that the instant you release the throttle and switch to regen you get 100% regen instead of a throttled amount. This is why the current Golden regen controllers use a microcontroller and software for everything instead of a commutation chip. I'm looking for a commutation chip that has PWM braking, and hence PWM regen built-in.
There is no way for a controller to do regen braking with the same FETs it uses to drive the motor since the motor voltage is less than the supply rail. It takes a second 3PH bridge switching into a boost topology in order to effect regen.
Dan
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And indeed the Golden regen controller uses 12 MOSFETs instead of 6, but there must be a commutation chip somewhere that offers the same regen capability in hardware versus using software and a microcontroller chip.
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mustangman, I got the 36V controller.
I was wondering, wouldn't a diode do the trick? (battery+ to anode; cathode to controller+; mode switch in parallel with the diode). I know a regular diode would pose a significant power loss, so I was thinking of a 'zero-volt diode' implementation with a power mosfet.
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mordaz, I was looking for the 48volt regen (version 3) that might get more speed and better regen braking than the 36volt version. Otherwise, I bought an extra battery to run my lighting with.(LOL) When RAGE had a sales, I got 4 18Ah SLA for 24.05 each including shipping(no sales tax) with the thought of upgrading to 48 volt for more speed since I live in California(30MPH limit!!). I will have to wait for MEB to finish up any testing and post results before I can make a decision. Email me if you have any questions. :D
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Instead of building your own MOSFET switch you can buy a 12 to 24 volt coil solid state 30 amp relay like power companies use in home energy management systems to switch water heaters on and off.
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I am in no rush to get a 48 volt regen controller, so I will wait for the results of beta tests. ;)
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myelectricbike,
My idea was to use a diode instead of a switch so that the batteries would be always 'on', except when the back emf from the controller exceeds the battery pack voltage. The diode would block the reverse current and the regenerative breaking would be disabled. A switch (or relay contact) could be used in parallel with the 'zero-drop diode', as a regen/freewheel switch.
Any flaws in this theory?
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myelectricbike,
My idea was to use a diode instead of a switch so that the batteries would be always 'on', except when the back emf from the controller exceeds the battery pack voltage. The diode would block the reverse current and the regenerative breaking would be disabled. A switch (or relay contact) could be used in parallel with the 'zero-drop diode', as a regen/freewheel switch.
Any flaws in this theory?
CEMF will never exceed the battery voltage. At full speed and no load it is still less than the motor voltage since it has to be overcome at any given speed to drive current through the motor. You need to boost the motor voltage past the battery voltage to allow regen braking.
Dan
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Mordaz
In concept a diode should prevent current from traveling in the reverse direction. You would need a diode that had a breakdown well above anything you might expect coming from the controller. The diodes in the regen controller are rated at 62 reverse breakdown volts and I think 62 amps.
cadstarsucks
In the setup Mordaz is describing (correct me if I am wrong) he would be inserting his device between the regen controller and the battery rather than between the motor and the battery so that his diode arrangement would be switching the "boosted" voltage from the controller. Can you explain to us how the voltage is boosted in the controller? Is it done with a voltage multiplier, or otherwise how is it done?
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In the setup Mordaz is describing (correct me if I am wrong) he would be inserting his device between the regen controller and the battery rather than between the motor and the battery so that his diode arrangement would be switching the "boosted" voltage from the controller. Can you explain to us how the voltage is boosted in the controller? Is it done with a voltage multiplier, or otherwise how is it done?
I am not sure what he is thinking off hand...I was thinking of adding regen to an existing system... I is conceivable that a regen controller could use the motor inductance as the boost inductor since the inductor want to keep current flowing in the driven direction while the CEMF wants to drive it in the opposite direction.
You would have to drive the motor to 20A and then let the motor inductance dump to the battery. Complicated on a BLDC to say the least. On the other hand a bridge into a boost circuit, while clumsy, is a doable add on.
Da
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myelectricbike, you got it right. This 'zero-drop diode' would be inserted between the batteries and the controller.
cadstarsucks, the idea is not to add regen to a regular controller, but to disable the regen function in a regen controller. Yes, of course cefm would never exceed the battery voltage. I meant the reverse current the controller feeds back to the batteries when breaking / reducing speed.
Am I right to assume the regenerative breaking would be disabled by such series diode?
Also, do you guys foresee any potential problem, like an overvoltage buildup due to the lack of a load (that is, the batteries to be charged)?
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A diode or a switch in the off position will disconnect the battery and hence the load, and the regen controller has no problem with disconnecting the battery and hence the load. Depending on the side of the battery to which you connect a switch there could be a spike problem for the controller, whereas a diode would eliminate the possibility of a spike problem for the controller altogether.
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It's actually a diode AND a switch. Here goes a pic of the idea.
When the switch is closed, the circuit is shorted and the regen controller behaves normally (regen mode).
When the switch is open, the circuit acts like a near zero drop diode, blocking any current from the controller to the batteries (freewheel mode, like the non-regen controller).
Do you guys think this would work?
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Thanks guys for all the information. :)
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Actually the controller may already be immune to spikes since power is normally connected by simply plugging and unplugging rather than using a switch.
The circuit you have drawn seems plausible for what you want to do but the issue for me with switching from a regen mode to a standard controller mode is on the opposite end. I need a circuit (actually a user selectable software routine) that will keep the regen controller from limiting top speed to the RPM of maximum efficiency while keeping regen fully operational for braking and downhill.
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I see. My aim is just to be able to pedal along with the motor without fighting the regenerative breaking.
I'll try the circuit and let you know the results.
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One of the new regen controllers I have, oddly enough still has the power cutoff break leads coming from the controller so that if you order a regen controller you might be able to specify that it is the one the also has the power cutoff break leads. Normally the power cutoff break levers come with the controller so just be sure they acknowledge your request and confirm this to be the case.
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Today I have tried the regen controller for the first time. I did not like it very much. Don't take me wrong, it works just fine, but it doesn't feel like a bicycle anymore. Changing the gears is also a problem, because you have to release the throttle in order to shift, and the regenerative braking kicks in. A freewheel/regen mode switch is really a must. I'll definitely try this idea. Or go back to the regular controller.
Speaking of a freewheel/regen mode switch, I was wondering, would it be possible to modify the controller instead of using an external circuit? Does anybody have an schematic of the regen controller?
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Another question that just came to mind: If I successfully disable the regen function (either using an external switching circuit or modifying the controller), is it right to assume the top speed limit be overriden?
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What did sales say, when you asked them?
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Actually I did not ask sales anything about this mod. I only contact sales (Philip) when ordering.
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The regen functions are under proprietary software rather than hardware control. Limitation on top speed comes from finding the RPM of maximum efficiency via software analysis and limiting top speed to it.
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I put my shifter on the left side so I could hold down the throttle while changing gears. I have a 21 speed so now, my 3-way shifter and the 7-way are beside each other. Looks different and takes some getting used to, but it works! Try that. I do not have a regen controller, but was like you and didn't want to take my hand off the throttle to change gears.
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Also the only reason why you cannot lift you hand off the throttle to change gears, wave at a friend, take a drink of water is the absence of a thumb screw. If you add one, however, be particularly cautious in its use. Eventually the controller may provide electronically controlled cruise control and you will not have to provide mechanically controlled cruise control of your own.
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I had read about erdurbin shifter placement before and it's a good idea, but I like being able to give the bike an electric push and coast for a while. Can't do that with the regen controller.
Anyway, this electronic cruise control would be great. I guess it could be disengaged by pressing the brakes, for example.
But I still want to give that freewheel/regen switch a try. I'm now looking for an automotive power mosfet for it.
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After applying throttle to the regen controller you can back off the throttle into freewheel and manually maintain throttle position there.
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I didn't know that it wouldn't freewheel because I don't have one. I think someone said earlier that you can give it the push you want and then just hold the throttle on just enough that the regen function doesn't kick in yet. Is this right? For example, hold the throttle around 5-10% so it is still pushing, but only at a minimal rate.
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Golden's new, new (for lack of a better name) regen controller is expected to allow the user to configure the width of the freewheel between throttle and regen. The first new (for lack of a better name) regen controller I got had a fairly tight freewheel but not overly so that you could not follow it all the way down to zero. The second one I got was a lot wider and had a lot wider freewheel at the bottom as well. The second regen controller also seems to have the power brake cut-off so that if you really want freewheel without having to follow it with the throttle then you just apply the power brake cut-off instead. Since I have not yet received the new, new regen controller that is supposed to let me program the width of freewheel that suits me I can't tell you much about it. Consequently I'm thinking about taking a throttle apart and redesigning it so that I can have cruise control.
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I was trying the regen controller on my delta trike and found one more reason for having a freewheel/regen switch. When maneuvering the trike in tight spaces, like my garage, I usually alternate between pushing it backwards with the feet on the ground and moving it forward with no power assist so I can have more control over it and not bump into anything. The problem is, with the regen control and zero throttle, it's like pushing a bike with brakes engaged.
OK, I know a simple on/off switch would do in this case.
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Does your regen controller have leads for the power brake cut-off switch levers? I have one that does and one that does not.
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I don't remember, but I'll have a look at it. I'll try my freewheel/regen switching circuit prototype anyway. I'm making a PCB for it right now.
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Hello,
I don't speak english very well, but reading you I'm afraid to have to understand that the regenerative controller has only 2 functions, depending on the position of the red button on the throttle : ON, with an enormous braking that oblige me to use power even on flat parts and down hills (!), and off, with only pedaling...
I have ordered it, and I am very disappointed with it : worst acceleration, lower speed, and above all a constant braking.
Is the red button only intended to cut the power off, when you don't want the regenerative braking to slow you down ? I can't test it by myself, because the thumb throttle that was sent to me has NO red button (and Mr Yao doesn't reply to my e-mails now...),
If so, it is not useful, because you have only 2 choices : either to use more power to move, or to cut the motor off and pedaling ?
After a short struggle against the motor in order to move in spite of its unwanted braking, I went back to my standard controller.
Did I miss something ?
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The thumb throttle with red button (push-on, push-off) switch I have did not come with the brown and yellow leads for the switch or the green and black leads for the level indicator LED's connected. The controller has green and black leads with a connector but I think these leads are for reverse rather than to power the green (+) and black (-) leads for the LED level indicator on the thumb throttle switch. Odd consideration to use identical lead colors on the thumb throttle and on the controller that do not match in function. Maybe this is why the thumb throttle did not come with these leads connected or with a connector for these leads. Mr. Yao would be the person to contact for a replacement and I think he has returned. Send him another email. Best of luck.
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I ordered a thumb throttle too, and it doesn't have any red button on it.
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So does anybody know how to decrease the braking of the controller when regenerating is not needed ? In a few words, what is the good method to use this controller ? Because as far as now, I can't use it in those conditions. Thank you.
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Have you done a search on "braking" or "regenerative" or other similar keywords? The topic has been covered at least once in this forum so if you do a search you will most likely come across an answer to that question.
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Sorry, I thought I was on the right topic...
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Don't worry, you're in the right topic, although the search function can often provide you exactly what you're looking for. myelectricbike can get testy sometimes--he has answered the question a few times in different threads, but they can get long and buried.
According to MEB, just keep the throttle rolled forward enough so it isn't braking, but not too far where it is providing power. As you slow down due to normal wind/friction, release the throttle a little at a time to match your current speed. This shouldn't use power from the batteries because the back-EMF generated by the motor matches the forward voltage coming from the controller, you essentially get near-zero current. It will probably take a while to get the feel for when you are coasting instead of applying a bit of power.
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That's a perfect explanation, OneEye. I understand that using the throttle is essential. Goodbye Pedelec, despite it is obligatory here in France. Thank you very much, I shall try the regenerative controller again.
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Thanks OneEye but now allow me to make several things clear.
The plan is to build a database of information that can and will serve to provide answers to question that have already been asked as well as to provide answers to new unasked questions but not to repeat previous answers over and over again. This idea supports a dynamic online FAQ and owner manual. There is of course the provision and prerequisite of a keyword search in order to make this plan work.
While additional detailed answers to questions which have already been asked are naturally welcome it is expected that previous answers to the same questions will have already been reviewed by the newbie or by anyone following their keyword search so that it will not be necessary to redirect the newbie or repeat the same answer over and over again.
Asking that a newbie do a keyword search as a prerequisite to asking a question is IMHO not too much to ask, especially since they are likely to gain even more information than the answer to an uneducated question most likely will provide.
I apologize if my response comes off as being testy because my very purpose of course in being here is to assure that newbies are not left in the dark and are in fact served but in addition to doing a keyword search there is another expectation I have for rendering this service free of charge. To be quite frank no one is here with legitimate purpose to help newbies who are too lazy to search for an answer and who resent the suggestion they should do a keyword search prior to asking questions because such newbies will come here to get what they want and serve themselves and then offer no help whatsoever in return. Such newbies who are unwilling to preface their questions with a keyword search, to be testy, not only mark themselves as lazy but selfish as well.
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Sorry, I wasn't trying to snipe at you. I've found, though, that even some the best information on some of these subjects tend to get buried within a thread and the threads get buried deep in the list. Some of our 5 page threads where we hash out the particulars of a particular technical question have great information, but finding that info within the thread (even if you know the right one) is a daunting task. The search function can help, but not always.
One feature that is useful when trying to compile an FAQ type list of topics that contain "approved" answers is a forum admin with the ability to make "sticky" topics that are kept up at the top of the forum.
Alternately, we need an FAQ forum where we distil the useful information out of our sometimes rambling conversations into concise posts. Only certain members could post to the FAQ forum. Ideally, threads in the FAQ forum would be exactly 1 post long; critique, discussion, and questions about an FAQ thread would be here, with the consensus answers being edited into the original post.
When we have something like that set up I'll join you in being testy/curt/terse when a repetitive/redundant/stupid question comes up ;D
Of course, with all the changes in the hardware coming from the factory, how long does it take for an answer here to become obsolete?
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Obsolescence... humm... naw. I don't think they will go to a 6 phase motor or do much more to the controller than add an SD card as I've requested plus microcode to turn the controller into a controller/data logger. The real issues that newbies seem to be having repeatedly are frame type, hanger, dropout or spacing problems, fuse problems, battery issues, sensor problems, phase lead problems, throttle and power brake cut-off problems and permisson from the
old hag ;D very sweet nice lady in the kitchen who has all the cash under lock and key. Lets see... seems like there was some thng else... maybe if I do a keyword search I'll come across what it is. ;D
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and permisson from the old hag ;D very sweet nice lady in the kitchen who has all the cash under lock and key
touché
Let me know when you get that FAQ sorted out and posted.
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:o Wow, such a nice welcome ! Thank you Yourelectricbike ! In spite of my lacks in English, your opinion about lazy and selfish newbies like me has reached my stupid brain (thanks to translators too).
I'm surprised about your knowledge about me.
First I didn't come here thinking "Bouououhhhhh, too tired to make a search, let me post a question anywhere, some stupid user will certainly answer..."
In fact, I was leaded by the link on the site towards your eulogistic (maybe a bit too much) adver... thread about the regenerative controller.
Then, I am not used to think in English, so it is very difficult for me to translate then assimilate all the technical informations buried everywhere.
Even in French, I am not a technician at all. So I tried to ask in a few words my essential inquiries.
Of course I am a newby, like I am on some other forums, where I don't miss to give back my humble newby (I know you like this word) experiences, and tell my (rather good at this point) opinion about my Goldenmotor kits to many virtual users in Europe.
Should every newby on this forum be considered as a "pique-assiette" ;), according to you, 145 users from 154 would be persona non grata.
Thanks again to OneEye.
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Fact is that by not following my suggestion to perform a keyword search to help make any questions less redundant and by not reading the topic from the beginning but instead engaging in the practice of nudging you have missed several answers to your question that such a search and reading may have revealed. If you do not desire to be persona non grata then do that which the label does not fit, namely asking less redundant questions by reading the topic from the beginning and doing a keyword search. You might also want to abandon your practice of nudging since you have not been here quite that long.
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No need to overreact, caradec, perhaps you are interpreting a bit more vitriol from myelectricbike than was intended.
Does the pedelec act as an on-off style sensor? i.e. if you reverse pedal or pedal at a very slow pace does it tell the controller you are "pedalling".
Or does it vary the allowed throttle based on pedaling speed?
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You too, myelectricbike... repeat after me: "breathe in.....breathe out...."
Repeat that a few times. There's no need for this to escalate into a pointless shouting match.
Cut the guy a little slack, please. He looked around in what he thought were the relevant threads, didn't find what he was looking for and posted in an appropriately titled conversation topic. English isn't his primary language, so keyword searches on different synonyms may be a bit much to expect. It's not like the information is perfectly presented...
Just chill, I think the question has been answered anyway.
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Actually I'm headed to the store on my regular bike since they have a buy one get one free sale and I definitely need the excercise. BTW - Philip is interested in the idea of adding the SD card to the controller to make a controller/data logger and will present it to his engineers. Before long, who knows, we may be riding fancy dancy MXZY1 $5,000 Golden ebikes of our own. 8) Converse amoung yourselves. :-X
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I approve your wise reaction, OneEye. Let's forget.
So you invite me to go on in this part of the forum :
You're right, my pedelec is an "on-off" model, not varying at all.
I have heard from another french user that he has a more progressive one.
Do Goldenmotors provide different kinds ?
With my kind of pedelec, I'm afraid there is no mean to use it with the new controller.
Another problem is that without a power cutoff button, you can't stop holding the throttle at the balance point, and the motor is always in use. Am I right ?
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Back to the topic...
I have just tried my freewheel/regen switching circuit. It turns out that blocking the reverse current from the controller to the batteries (like a series diode would do) does not result in freewheeling at all. That said, this circuit is useless. But I still want to be able to disable the regen function. As you can see in the attached schematic, I intend to keep the regen braking even when the regen function is disabled.
Now I think modifying the regen controller is the way to go. I'd appreciate any help.
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Have you ever visited the Endless-sphere Forum (http://endless-sphere.com/forums/viewtopic.php?t=764)? I was shocked at the depth of dedication to repair and reverse engineering all of its members seem to have. If you are deeply into electronics then that is the place to give and to get help, especially for circuits to solve problems that most people are content to just live with.
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I am a member of the endless sphere forum as well, there is tons of info there but none that I have found on golden motors. Is there any detailed info on how the regen works, I thought I saw a review on it now I cannot find it.
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The problem is the startup delay,
you hop on and pedal, then hit the power switch,
and regardless of throttle position the regen brakes
hit full blast until the controller initializes.
It takes a few seconds, but that means a screeching halt
while you wait for the 'click' after pressing the red button.
Ok, I'm no electronics expert, but could you have
three relays cut out the field coil (power) connections
between the controller and the motor?
When I don't want regen, I probably don't want power either.
The sensors will probably freak and send 'more current'
request to the controller, but with an open circuit you get
zero amps out.
Elmer.
Ebike in a state of flux. Now=.5kW kit with 3xSLA on the cheapest bike I could get.
The next order is a kW front wheel on a $60US Diamond Back Cruiser
with an under-published 48V20AH LiFePO4 pack.