NEW Gotway Monster 100V

[Marty Backe]

3 hours ago, meepmeepmayer said:

@Marty Backe I know nothing about electric motors, just my thoughts:

67V is 12% over specification.

84V is 40%.

100V would be over 65%.

So I'm wondering, what is a "60V motor" when you can overuse it by that much and it still works? Anyways, maybe it is possible.

But if my cables melted at 84V, should it not be even easier to melt the same cables (assuming) by using a lot of power (uphills...) at 100V? Will a 100V wheel be even more in danger of damage due to high power draw (because it's easier to demand power)?

I'd want some definitive safety guarantees (like new parts, cables) from GW before considering a 100V msuper.

My undergraduate degree was in electronics, many moons ago. That being said, I never studied motors.

Higher voltage means less current flowing thru the wires which means lower temperatures. That might be side benefit to the wheel manufacturers for moving to higher voltage systems - they can user lower (smaller) gauge cabling between the motor and the electronics.

For practical purposes (in terms of voltages likely to be applied in our EUCs) motors are current limited not voltage limited. They are destroyed when too much current flows through the coils. As long as the current is limited much higher voltages could be used.

I think the power electronics and battery configuration is the long pole when moving to higher voltage EUCs. The motors and cabling are the easy part of the equation.

[Carlos E Rodriguez]

Its all about the AMPS. The voltage is just a potential differential to cause AMPS to flow through a circuit. With higher voltage the electronics can fight the motor back EMF to allow the AMPS to flow as the RPMs get higher.

To cause an electromagnetic field of X strength you need to put Y amps though the coil. Voltage is not the issue but a tool.  The computer pulses voltage at the necessary duty cycle to induce the necessary current to produce a electromagnetic field to act with the magnets and move the wheel with the necessary force and accelerate based on what the rider is asking it to do and maintain balance. That is why the motors make that high pitch notes. They are pulsing voltage to produce current in the coils. Its all about producing an electromagnetic field by running AMPS on the coils.  The maximum magnetic field will be when the pulse is 100% duty cycle and it gets pulsed on and off for each phase and I dont believe the system goes that high (100% duty cycle) because it would burn the wires( too much amps).  But a higher input voltage would allow to provide AMPS at high RPMs. To calculate the power to the motor you can not use the system voltage.  YOu have to use the AMPS through the coil and the resistance of the coil. I^2R and adjusted by the duty cycle of the PWM voltage modulator.

[Mono]

Yet another voltage change. It becomes more and more evident that Gotway does not so much aim at building better EUCs, but building EUCs with record labels that they hope will sell. I can't argue with sales numbers, but it's a sad development anyways.

[Pingouin]

12 hours ago, Marty Backe said:

Thanks, but my desire is for the 100v MSuper - it's needs more oomph for climbing hills. 

Hi, doesn't the 84V Msuperv3s+ serve that purpose already ? People seem to say (wiring issue put aside) that it is a great powerful wheel in all situations.

 

14 minutes ago, Mono said:

Yet another voltage change. It becomes more and more evident that Gotway does not so much aim at building better EUCs, but building EUCs with record labels that they hope will sell. I can't argue with sales numbers, but it's a sad development anyways.

What do you mean by "better EUC" ? There are no corrolation between voltage and quality if that's what you're refering to, gotway had issues with the solder mealting up in extreme conditions, but other companies also had their issues (fried motherboard, fragile axles, broken pedals..) EUC are still under development and I think that the final product is still to come out.

I haven't heard of any issues (but they might be some, correct me if I'm wrong) with the Gotway Monster so far, it wouldn't be is Kebye's interest to give us a bad Monster upgrade, but again I may be wrong but hope not.

If nobody was asking for more power, I think they wouldn't come out with this little guy, so there is certainly people that have asked for it

[Mono]

4 minutes ago, Pingouin said:

What do you mean by "better EUC" ?

That's not a serious question, or is it? 

4 minutes ago, Pingouin said:

There are no corrolation between voltage and quality if that's what you're refering to,

Right, that is exactly the point, higher voltage doesn't make the EUC better, it mainly introduces new challenges the manufacturer has to address additionally. 

4 minutes ago, Pingouin said:

[...]

I haven't heard of any issues (but they might be some, correct me if I'm wrong) with the Gotway Monster so far

4 minutes ago, Pingouin said:

it wouldn't be is Kebye's interest to give us a bad Monster upgrade, but again I may be wrong but hope not.

Of course they don't want to make a bad product, but one has to focus on the right things to get a difficult job done, which is true for any difficult job. 

4 minutes ago, Pingouin said:

If nobody was asking for more power, I think they wouldn't come out with this little guy, so there is certainly people that have asked for it

Voltage and power are slightly different things. But sure, they aim to do what sells and I can't argue with sales. It remains to be sad though as we don't have so many candidates that could come up with a decent EUC product.

[esaj]

Surely it can be done, just a matter of designing and testing it properly. Tesla's (the cars) use something like 350-400V

I'd see that the 100V will need modifications on their mainboards, like the CPUs/MPUs use 3.3V or 5V, the buck-converter power stage probably needs to be partially redesigned to bring the voltage down to those levels with even higher input voltages, the current mosfets used in the high-power wheels seem to have Vds 100V max, and could breakdown due to high voltage of the battery or voltage spikes from the motor, so probably change those to higher voltage models... But I trust their engineers know what they're doing (at least they know a hell of a lot more than me )

Could the spikes become high enough to arc between the cables when they're pushed close together inside the axle shaft? I've ran some small motors with 9V DC, and saw inductive spikes going up to around 100V, so roughly 10 x the battery voltage... But don't recall whether it was 3-phase BLDC or 1-phase brushed motor. Also the high battery voltage makes it more likely to get a (very painful or lethal) electric shock, although that shouldn't happen unless there's a really bad design fault or you stick your hands in the wrong place (which the casing should prevent anyway)    

[Pingouin]

@MonoI don't ask lazy questions, so yes it was a serious question..

Higher voltage, as for what I have seen on the ACM, means a much safer EUC at higher speeds, plus (aside from the wiring issue that is now solved) it is much safer while climbing a steep hill, while before some riders experienced cut off due to overpower.

If Kebye want to keep it's reputation, then if they already made a mistake while upgrading from 67V to 84V, making the same mistake again could be very negative for the company, so they shouldn't.

Voltage & power may be different thing, but higher voltage gives the feeling of having more power, alot more. I said we don't have the perfect product, but I think we already have several decent product, even in the car industry no car is perfect, it's the same for EUC, that doesn't mean there are no descent ones

Going back to the Monster, I think, and hope, it'll be a great improvement on the original Monster, and I'll share my thoughts with you when I test it

 

 

[Marty Backe]

3 hours ago, Mono said:

<snip>
Right, that is exactly the point, higher voltage doesn't make the EUC better, it mainly introduces new challenges the manufacturer has to address additionally.
<snip>

The 84v ACM is better than the 67v ACM, likewise the MSuper. In both cases they have noticeable improvements in acceleration and top end speed. They are better wheels.

So if they go to 100v systems it won't be just for marketing, they will be delivering better wheels.

[Marty Backe]

4 hours ago, Pingouin said:

Hi, doesn't the 84V Msuperv3s+ serve that purpose already ? People seem to say (wiring issue put aside) that it is a great powerful wheel in all situations.

<snip>

For someone (me) who enjoys climbing steep hills in the mountains, even the ACM would benefit from additional power. So I would buy a 100v MSuper over the 84v MSuper any day of the week.

The MSuper V3s+ is a great powerful wheel, but that doesn't mean it couldn't be better.

[Mono]

22 minutes ago, Marty Backe said:

For someone (me) who enjoys climbing steep hills in the mountains, even the ACM would benefit from additional power. So I would buy a 100v MSuper over the 84v MSuper any day of the week.

In my experience, climbing ability is usually more limited by the pedal size than by the wheel power. I don't have experience with the ACM or the MSuper though. What is the sizes of their pedals?

[Marty Backe]

5 minutes ago, Mono said:

In my experience, climbing ability is usually more limited by the pedal size than by the wheel power. I don't have experience with the ACM or the MSuper though. What is the sizes of their pedals?

I don't have any measurements handy, but the ACM and MSuper pedals are very comfortable, and not small at all. The Monster shares the same ACM pedals.

The MSuper pedals are noticeably larger than the ACM pedals yet the MSuper is a worse hill climber than the ACM.

The ACM, MSuper, and Monster can all climb steep hills, but the ACM goes fastest and with the least amount of effort (hard leaning forward). In my experience (owning all three wheels), wheel diameter seems to be the determining factor in ease of hill climbing and acceleration.

[US69]

4 minutes ago, Marty Backe said:

wheel diameter seems to be the determining factor in ease of hill climbing and acceleration.

Exactly on point, Marty! Same motors...diferrent wheel size...means the smaller wheel has best acceleration and torque!

[Mono]

14 minutes ago, KingSong69 said:

Exactly on point, Marty! Same motors...diferrent wheel size...means the smaller wheel has best acceleration and torque!

Only that not all wheels have the same motor  And even then may the pedal size be the limiting factor if the motor is strong enough.

gives a nice sketch of the problem. 

[Mono]

 

4 hours ago, Pingouin said:

I don't ask lazy questions, so yes it was a serious question.

Everything else being equal, an EUC is better when it is

• safer or
• more reliable or
• more durable or robust or
• more comfortable to ride or use or
• easier to ride or
• simpler to use or
• lighter or
• having more range or
• allowing more relevant settings to be made by the user or
• consuming less energy

I am pretty sure the list is not complete. One might think that a faster EUC is also invariably better, but I can immediately see at least two reasons why this may not be the case: 

• it may become illegal
• it may be intrinsically less safe in particular if the app does not allow to set lower max speed limits

So I'd consider a faster wheel different, but not invariably better. 

Quote

Higher voltage, as for what I have seen on the ACM, means a much safer EUC at higher speeds, plus (aside from the wiring issue that is now solved) it is much safer while climbing a steep hill, while before some riders experienced cut off due to overpower.

The 84V ACM may be better than the 67V ACM in these aspects, or possibly in any other aspect, but a higher voltage was not the necessary crucial means to achieve these improvements, or for any other possible improvement on the above list (while a change from, say, 6V to 60V probably is a crucial change to get better wheels in the above sense).

[Pingouin]

1 hour ago, Marty Backe said:

For someone (me) who enjoys climbing steep hills in the mountains, even the ACM would benefit from additional power. So I would buy a 100v MSuper over the 84v MSuper any day of the week.

The MSuper V3s+ is a great powerful wheel, but that doesn't mean it couldn't be better.

I hear you Marty, if I hear about a Gotway Msuper3 100V or ACM 100V I will share the info, but for now it seems that Gotway is shipping the first 100V Monster & will soon come out with the new MCM4

I'm still not convinced they will come out with new versions of the Msuper3 & ACM, instead I guess they will come out towards the end of the year with ACM2 & Msuper4 which could be available in 84V & 100V, seems logic to me (but maybe I'm wrong).

EUC are becoming incredible performance machines and I'm very excited to see the new models coming out !

[Ch.Eng.62]

Regarding voltage and power, the modern passenger ships propulsion system is diesel electric. It means that there's a set of diesel generators and propellers driven by electric motors. The voltage is above 7000V (for reducing the AMPs) and the power is above 20MWt. 

[meepmeepmayer]

Wouldn't the higher voltage just be used to increase the power (which is the point after all), so the current won't necessarily decrease?

[Mono]

41 minutes ago, Ch.Eng.62 said:

Regarding voltage and power, the modern passenger ships propulsion system is diesel electric. It means that there's a set of diesel generators and propellers driven by electric motors. The voltage is above 7000V (for reducing the AMPs) and the power is above 20MWt. 

Interesting, what do you mean by 20MWt? It obviously can't be 20 mega Watt, right? I guess it's 20MW = 20,000kW (or thirty thousand EUCs, in other words), so then with 7000V we have around 3000A current under full power 

I didn't know this and it is kind-of funny that a 2-fold electric conversion can be used as an efficient gearing system. Though, this is what we have in hybrid cars as well, so I did know this part.

[Mono]

5 hours ago, Marty Backe said:

I don't have any measurements handy, but the ACM and MSuper pedals are very comfortable, and not small at all. The Monster shares the same ACM pedals.

There seem to be different opinions about pedal length of the ACM then.

The pedals seem to be 15mm shorter than the Ninebot pedals. According to the original drawings they are 205mm long.

The current InMotion pedals are 212mm long. This means, AFAICS, that the ACM (and the Monster) must be weaker climbers than the V8 and that would not change even if we provided the ACM with 300V or 7000V. Why? Because the climbing limitation of the V8 comes, to all I know (and have read), only from its pedal length, at least for a weight load of up to 85kg. More torque of the motor does not help, because the rider does not have the pedal leverage to produce the necessary (equivalent) counter torque.

 

[Rehab1]

9 hours ago, esaj said:

But I trust their engineers know what they're doing (at least they know a hell of a lot more than me )

Don't undercut your talent! You should apply for an engineering  job!

[EUCMania]

10 hours ago, Marty Backe said:

I don't have any measurements handy, but the ACM and MSuper pedals are very comfortable, and not small at all. The Monster shares the same ACM pedals.

The MSuper pedals are noticeably larger than the ACM pedals yet the MSuper is a worse hill climber than the ACM.

The ACM, MSuper, and Monster can all climb steep hills, but the ACM goes fastest and with the least amount of effort (hard leaning forward). In my experience (owning all three wheels), wheel diameter seems to be the determining factor in ease of hill climbing and acceleration.

When climbing hill of 20 degree on my Msuper 3 67v, just lean forward to press the pedal is not enough, one has to squeeze the Msuper on the pads using lower leg and bend it forward to produce more demand of torque. I have not been able to over lean the Msuper 3 in this way yet ( at low hill climbing speed). My calculation shows that the pedal length of the MSuper 3  is just driving up a 18 degree incline with reasonable margin for your shoes to press. At speed 0, one can put about 44kg of force on the front -1cm of the pedal. At half of cutoff speed, one can put 22kg of downward force.

  

[Ch.Eng.62]

8 hours ago, Mono said:

Interesting, what do you mean by 20MWt? It obviously can't be 20 mega Watt, right? I guess it's 20MW = 20,000kW (or thirty thousand EUCs, in other words), so then with 7000V we have around 3000A current under full power 

I didn't know this and it is kind-of funny that a 2-fold electric conversion can be used as an efficient gearing system. Though, this is what we have in hybrid cars as well, so I did know this part.

Yes, 20,000kW. It is the power required for moving the big passenger ships (about 250 meters long and 35 meters wide). It is NOT the most efficient system, but have advantages for passenger ships. 

So, for increasing the power it is compulsory to increase the voltage, it is not new for the industry, but what is the safety limit for EUC? And do we really need this? 

[Mono]

5 hours ago, Ch.Eng.62 said:

So, for increasing the power it is compulsory to increase the voltage

Power still equals voltage times current.

5 hours ago, Ch.Eng.62 said:

what is the safety limit for EUC?

I guess the main problem could be legislation. For example, the EU low voltage directive^1 covers equipment operated with voltages between 75V and 1500V DC. That is, to my understanding (without any legislative insider knowledge), 67V charging does not need to follow this directive, 84V charging does. Yet, 84V charging EUCs are sold and can be bought currently in the EU, so it might not be a decisive problem. 

5 hours ago, Ch.Eng.62 said:

And do we really need this?

No, I don't think so, neither do we need 20,000kW, nor do we need 100V. But it sells, to some extend 

BTW, the fuse in the Tesla Model S cars is rated for 1500A.^2

^1 https://en.wikipedia.org/wiki/Low_Voltage_Directive
^2 http://www.autoblog.com/2015/07/17/tesla-announces-model-s-ludicrous-upgrade-90-kwh-battery/

[Mono]

8 hours ago, EUCMania said:

At speed 0, one can put about 44kg of force on the front -1cm of the pedal. At half of cutoff speed, one can put 22kg of downward force.

Can you explain how you computed these numbers?

[OliverH]

On 17.4.2017 at 0:19 PM, Mono said:

Power still equals voltage times current.

I guess the main problem could be legislation. For example, the EU low voltage directive^1 covers equipment operated with voltages between 75V and 1500V DC. That is, to my understanding (without any legislative insider knowledge), 67V charging does not need to follow this directive, 84V charging does. Yet, 84V charging EUCs are sold and can be bought currently in the EU, so it might not be a decisive problem. 

No, I don't think so, neither do we need 20,000kW, nor do we need 100V. But it sells, to some extend 

BTW, the fuse in the Tesla Model S cars is rated for 1500A.^2

^1 https://en.wikipedia.org/wiki/Low_Voltage_Directive
^2 http://www.autoblog.com/2015/07/17/tesla-announces-model-s-ludicrous-upgrade-90-kwh-battery/

Reading LVD (http://www.ibf.at/fileadmin/infomaterial/2016-11-21_LVD_Guide.pdf) specially $51 Safety Objectives it has the same sentences as street laws:

2. Protection against hazards arising from the electrical equipment

Measures of a technical nature shall be laid down in accordance with point 1, in order to ensure that:

(a) persons and domestic animals are adequately protected against the danger of physical injury or other harm which might be caused by direct or indirect contact;

(b) temperatures, arcs or radiation which would cause a danger, are not produced;

(c) persons, domestic animals and property are adequately protected against non-electrical dangers caused by the electrical equipment which are revealed by experience;

(d) the insulation is suitable for foreseeable conditions. 

3. Protection against hazards which may be caused by external influences on the electrical equipment

Technical measures shall be laid down in accordance with point 1, in order to ensure that the electrical equipment:

(a) meets the expected mechanical requirements in such a way that persons, domestic animals and property are not endangered;

(b) is resistant to non-mechanical influences in expected environmental conditions, in such a way that persons, domestic animals and property are not endangered;

(c) does not endanger persons, domestic animals and property in foreseeable conditions of overload. 

 

And EUC must comply also to Safety of machinery 2006/42/EC regarding Article 1and 2:

http://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:32006L0042&from=DE

 

And this was a Short introduction where PLEV has started some time ago.