xiiijojjo Posted February 13 Author Share Posted February 13 (edited) !OUTDATED READ LATER POSTS! Okay so no matter how I look at this my total backpack weight is simply getting too heavy and maybe I should rethink this project for the Master Pro v3. One really heavy component is the 250V60A mppt solar charge controller at 3kg/6.6lbs, by using a 134V wheel such as the Master Pro v3 I could get away with only using a 150V mppt solar charge controller which is cheaper and lighter, the ampacity of which should be sized for the max discharge rate the EUC charge ports can safely handle. I can't find specific info on v3 charge ports anywhere online, but I would imagine they can output more than the v2 considering the former has 50S cells.. Even so I can't find any specs online so I'll just use the specs from the v2 which are revealed on https://www.ewheels.com/product/begode-masterpro/ Quote What is the maximum rate of charge? On anything greater than a 32s4p/128 cell 21700 battery pack, the bottleneck tends to be less with the cells, but rather with the other components such as the charge-board, wiring & BMS. Charging at 14A is considered ‘acceptable limits’ but in excess of this, may cause damage to the other components. So let's assume 14A also means 14A out. Low power tilt back alarm starts at 95V. So 95-134V 14A = 1330-1876W of output depending on EUC battery charge. I could go with the 150V35A mppt at 1/3 the price weighing only 1,25kg/2.75lbs compared to the 250V60A at 3kg/6.6lbs I would also save weight on using smaller gauge wire with this setup. The only thing that sucks about this 134V setup is if the v3 is limited to 14A out, making it impossible to hit 2000W minimum at low voltage. 2000W/95V=21A, so I'd need 20A ports, this is the only real reason I picked the ET MAX in the 168V version. I could always just go with a smaller 1000 or 1500W inverter, and save even more weight, but I really like the idea of using a 2000W electric induction stovetop at full blast, but since they can be dialed between 0-10 I guess I'd be fine with a smaller 1000W inverter. In fact I have a Bluetti ps72 1000W powerstation that I won't be using. I think I will remove the internal battery from that powerstation and in its place I will put the 150V30A solar charge controller, then I just remove the cigarette lighter charge port to have PV+/- cables accessible (for either charging with solar or discharging with EUC) Or maybe I can make a lighter and smaller custom box, using only the front panel (AC out, DC IN/OUT, Monitor), and the wireless QI charger in top panel, and the internal inverter, and of course the victron 150V35A mppt. I will look into that option depending on how full my backpack will be fully packed. In any case I will admit that a bit more thinking has made me realize this project is probably a lot more doable with a 4800WH Master Pro v3 paired with the smaller weight and size of the Bluetti ps72 mod described above, even if that means settling for a smaller inverter. Edited February 15 by xiiijojjo Quote Link to comment Share on other sites More sharing options...
xiiijojjo Posted February 14 Author Share Posted February 14 (edited) I just did a ton of reading and sadly came to the conclusion that running a "regular inverter" without battery is not really recommended for neither the inverter nor solar charge controller. I should apparently ideally get a "hybrid inverter" made for the exact purpose of taking solar into an mppt charge controller and outputting directly into an inverter that can operate safely, without needing a battery at all. So now I'm looking into those, hopefully I'll find a small and light-weight one... It's honestly got me thinking about just giving up on having no battery at all. I may have to go for the smallest possible 12-24V, not for capacity simply for not having to get a hybrid inverter as they all are huge. After some more thinking I got the idea: Maybe I can use a grid-tie inverter, disable the anti-islanding protection somehow, Then I connect EUC -> grid-tie inverter (where solar is permanently connected) -> my own 180 V-280 V grid... I can't find anything on disabling the anti-islanding protection feature online, and I understand why, it's there for a very important reason, so lineworkers don't have to deal with your live wires... Instead of trying to turn the protection off, maybe I just need to find the smallest powerstation capable of outputting 230VAC to simulate the grid being on, making sure the anti-islanding protection doesn't kick in. This may actually just work reading about it online people say that the grid-tie inverter would likely kill the powerstation used to simulate the grid being on, by continuously charging it through the VAC ports which it can't handle according to people online. Looking into if info on grid-tie inverters being used in ac coupling with an inverter/hybrid inverter... Much reading later... It is possible to run the grid-tie inverter off a regular inverter, saving a ton of money and weight in the setup. I can get a small 12v 8ah battery to power the regular inverter, providing a "grid" to the grid-tie inverter allowing it to run, however the HUGE downside to running it with a regular inverter vs a huge bulky hybrid inverter is that the regular inverter will blow capacitors if no load is connected, or rather if the load is smaller than the wattage produced by the grid-tie inverter. Still I prefer the cost saving and light weight nature of this setup, so I will now try to come up will a way to have a reliable constant load running on this "grid". So I did look into it but I found no reliable, safe and easy way of constantly ensuring that no power was fed back into the regular inverter. So a hybrid inverter is my ONLY way going forward, I can even get a "all in one" hybrid inverter which means it has the option to turn into a grid-tie inverter, in case I want to stop living nomadically for a while but retain the ability to have my portable solar generation lower the power-bill where ever I happen to live, rather than a "regular" hybrid inverter which cannot feed power back into the grid. Edited February 15 by xiiijojjo Quote Link to comment Share on other sites More sharing options...
xiiijojjo Posted February 15 Author Share Posted February 15 (edited) Newest development after a lot of reading, video watching and thinking. I'm leaning toward simply using only this "all in one" hybrid inverter, solar panels, and nothing else (yet another niche category of inverters that have the all the capability of a regular hybrid inverter + the ability to switch over to grid-tie mode) It can run without a battery and I can connect both solar and EUC to its PV+/-. It's only 4,6kg/10.1lbs and the long, slim design would fit into my backpack, takes 30-400VDC so any electric unicycle ever made or that will be made for a looong time as we're only at 168V at this moment. These are the solar panels I will use for the setup (already mentioned in the OP) I can get away with using as little as two of these in series considering the Vmp of one panel, to go above the 30V minimum for the mppt of the hybrid inverter to start converting solar/EUC from 30-450VDC into 230VAC. I may end up using up to 4 of these solar panels depending on total packed backpack weight. Now that it seems that I've found out what type of setup I'm going for I have to spend a good amount of time watching reviews of all the 3000Wh+ EUCs. I'm certainly leaning heavily towards the Master Pro v3 because of the 4800Wh. For doing this thing nomadically I really want as much battery as possible inside the EUC because I won't have to carry the battery myself, so I may as well get the biggest battery possible. Another benefit from picking a big battery model is the wide 20-24 inch wheel diameter which, in my opinion, is ideal for prolonged travel going 40-70kmph/25-45mph or faster. My biggest concern about the Master Pro v3 and other big capacity EUCs is their suspension, especially the ones using linkage suspension like the Master Pro v3. Edited February 15 by xiiijojjo Quote Link to comment Share on other sites More sharing options...
xiiijojjo Posted February 15 Author Share Posted February 15 (edited) Here is a mod I've made for the all in one hybrid inverter to do all of the things envisioned in the original post. Let me know what you think. I'm very happy to have learned so much in these past weeks. When I began this I was barely an amateur electrician, but now I'm at least adept, and have gained so much knowledge about different types of inverters, solar charge controllers etc. Edited February 16 by xiiijojjo Quote Link to comment Share on other sites More sharing options...
xiiijojjo Posted February 16 Author Share Posted February 16 (edited) I have made a list with the weight of every single thing I would bring with me, and I have removed all but the bare necessities and still have a weigh of 28,6kg/63lbs which is simply too much.. I want to get down to 20kg/45lbs and I think the only way for me to do this project is to mod the EUC to be able to store some stuff, removing weight from my backpack. The fact that I prefer the Master Pro v3 is great considering I could get the kickstand, and add a few parts to it to allow it to lock into place when folded out. Doing this would allow me to install panniers or "bicycle luggage" to the front or rear (or both ) of the EUC. This would allow me to off-load a TON of weight from the backpack and allow me to bring my 8L cooler/freezer, and a ton of other things I had started to give up on ever being able to bring. Getting something like this 65L pannier would certainly do the job, I could also strap the 8L cooler/freezer onto the back of this. Using one of these I've been able to get the backpack weight down to 46lbs, but the weight of the pannier is already the same at around 46lbs. The EUC should be able to handle it though. Total weight of me+pannier+backpack = 125kg/275lbs The Master Pro v3 should be able to handle that. It supports up to around 300lbs according to Ewheels.com Update: Came up with this I'd obviously remove the stock rear stand. Not sure if mounting it to where the battery cases are mounted would work. I'm afraid it'd be too much weight, so I probably have to develop supports to the frame that connects to a lower point on the EUC. After a lot more thinking I don't think the above mod is a good idea. There's to much weight too far forward and backward, negatively affecting the ease of control, also in case of a crash the frame most likely end up breaking, which would be fine if I wasn't going to use this to live nomadically, so I need this EUC to be able to withstand a crash while retaining the ability to carry a lot of volume and weight. So instead of that mod I think I will be using a large capacity backpack with the proper dimensions allowing for me to strap it on top of the EUC with elastic hook straps. Something like this 45L backpack would be great. If I store the sleeping bag and clothes in the bottom of the backpack I'd have a nice, comfy and raised seat for long drives. This would allow me to keep the total weight/price down, I won't have to mod the EUC, and more importantly I get to store everything in one big backpack mounted on top of the EUC raising the center of gravity and the seat. Edited February 19 by xiiijojjo Quote Link to comment Share on other sites More sharing options...
xiiijojjo Posted February 18 Author Share Posted February 18 (edited) So if this hybrid inverter can in fact run without a battery I may as well go for the 3000W 24V version since I won't need 12V battery compatibility, but after contacting the manufacturer I've been informed that it DOES need one, and that the models that work without a battery are twice as heavy. This lead me to further research and I discovered motorcycle batteries, which feel like a real eureka moment for this project. Since I may be able to go back to using a victron mppt -> battery -> inverter, the only reason I abandoned that plan was because of needing batteries and at this time I though I would need a massive 100Ah battery to supply a 1000-2000W inverter because of the needed amperage. But since I've discovered motorcycle batteries it's become apparent to me that I could get something as small as a 12V 6Ah motor cycle battery with as high of a CCA rating as possible. Quote " CCA is a rating used in the battery industry to define a battery's ability to start an engine in cold temperatures. It is easier to start an engine in a warm environment than in a cold one. The rating refers to the number of amps a 12-volt battery can deliver at 0°F for 30 seconds while maintaining a voltage of at least 7.2 volts. The higher the CCA rating, the greater the starting power of the battery. " If I get a 12V 6Ah with 480CCA that's 12x480A= 5760W, and since I won't ever push 1/3 of that, I probably won't get a voltage drop so steep that the inverter shuts off... But I have no idea what their maximum rated continuous charge/discharge current is, but have a bad feeling they aren't made for continuous high discharge. If that is the case I will have to settle for using one 12V 6Ah motor cycle battery in the hybrid inverter mod. It doesn't add that much more weight and the hybrid inverter would work with such a small battery. I should probably also go for a 168V 20A EUC like ET MAX even if those wheels currently only have 3000Wh batteries, it won't really be a problem considering I will be fast charging most of the time, something that would take a long time with the Master Pro limited at 134V 14A max. So I'd rather have 1800Wh less battery in exchange for insane charge/discharge speeds. That fat 90/90 14 tire also looks like it was purpose made for how I'll be traveling. Edited February 19 by xiiijojjo Quote Link to comment Share on other sites More sharing options...
xiiijojjo Posted February 19 Author Share Posted February 19 (edited) Mmmh a lot more researching later and I'm back with another idea to create what I proposed in my original post, without it getting overly complicated, or involving components I don't want, like a hybrid inverter. I have been looking into different types of dc/dc converters and found the isolated dc/dc converters. After further research I found out that I can connect them like: Solar panels -> isolated dc/dc converter -> inverter. This is the setup I wanted from the start. It's simple, cheap, small and light-weight, and a LOT more practical than carrying around a hybrid inverter in a backpack, and with the hybrid inverter you need at least 2-3x200W panels for the hybrid inverter to even work. Whereas with these isolated dc converters you could start with as little as 1x200W panel. You can also wire more of them in parallel to increase power to inverter. Yes the setup will be heavier than the hybrid inverter mod, but it won't need a heavy battery to work so overall the weight is lower, and I can design the size of the container where I put all the components to perfectly fit as a seat that doubles as a storage box. Then I can carry the heaviest things on the EUC and the most fragile in my backpack. I would use these isolated dc/dc converters in parallel for (168v) EUC discharging. They are only 1,6kg/3.5lbs per unit and the specs: https://aliexpress.com/item/1005005539011055.html?spm=a2g0o.store_pc_allItems_or_groupList.0.0.7921767cCsAvvX&gatewayAdapt=glo2deu This is perfect for a 168V EUC, and at that low weight you could easily start with 1 and upgrade to having 2-3 later on. Meaning I could buy a 12V 2000W inverter and only run it at 800W max, until I buy two more converters to be capable of drawing the full 2000W with overhead by using 3 of these in total. Total weight of setup 3x1,6kg/3.5lbs per unit = 4,8kg/10.5lbs + 12V 2000W inverter (with metal shroud removed), 2x140mm-200mm computer fans + the box I build to compactly house all of this. Sure this weight is greater, but it's a sacrifice that's worth it to me, considering I can have that box double as storage for the heaviest equipment I'll be bringing with me. If I can get the company that make these to make a version for me that take 18-180VDC instead of 105-180VDC I won't have to get another unit purely for solar input. If the company can't custom make one for me with those specs I could just get another converter just for taking 18-35VDC solar in, and it wouldn't add much weight. I could just get two of these 300W converters for 3x200W solar panels only adding another 1,1kg/2.5lbs https://www.aliexpress.com/item/1005003460479084.html?spm=a2g0o.detail.0.0.7e38B2CeB2Ceif&mp=1&gatewayAdapt=glo2deu Edited February 20 by xiiijojjo 1 Quote Link to comment Share on other sites More sharing options...
xiiijojjo Posted February 20 Author Share Posted February 20 (edited) Excuse me guys, I'm no 3D modeler but I taught myself enough to start making a 3D model of the box. Made it long and big enough to fit all the solar panels, and most of the equipment. I also made the sides taper to avoid pain. Measured my inner leg length and the pedal height and I think I can get away with a box this tall. PROTOTYPE ALERT: more details will be ironed out, I will eventually design the internal layout, taking inverter&converter size and placement into account to make 100% sure everything will fit & work. *Updated the design I will most likely end up needing to make the box more narrow too as 330mm is the widest point on the EUC. Maybe the box needs to be 250-280mm to not dig into my shins. I will also add a front handle for breaking and accelerating. * Added solar panel storage * Added 2000W inverter and 3x isolated converters I have confirmed that all my other gear will fit. especially since I can use the inside of the solar panels for the majority of my storage. I will only have to carry my laptop in a low-profile backpack, so It won't be in the way of me using the cooler as back support, for seated riding. * Added solar converters and a 140mm fan * Added color * Added a cutout for where my legs go to guarantee no uncomfort, it may allow me to take the front and rear wider. * Expanded the leg area, moved the electronics to the front, rotated the cooler. * Made the design longer which may look like a bad idea, but the reason was weight redistribution. The majority of the weight will be stored within the solar panels (which will not be a perfectly round roll, but will conform to the triangular space, in turn increasing storage volume) so I had to move them closer to the center of gravity. I also made an attempt to balance the front and rear, however there's still move weight in the rear. Placing the bar for braking and accelerating is difficult at the moment as I don't have an EUC to do testing with yet. Edited February 21 by xiiijojjo Quote Link to comment Share on other sites More sharing options...
xiiijojjo Posted February 22 Author Share Posted February 22 (edited) I keep working away at the 3D prototype, but then I started looking into non-isolated dc-dc converters and the potential issues of running them to the same busbar (inverter DC in +/-) and found out that I'll need to replace the 2x non-isolated inverters out with a viable isolated one, since everything will be connected to the busbar for the simplicity, and for weight saving purposes. DON'T USE NON-ISOLATED DC-DC CONVERTERS IN SERIES OR PARALLEL TO THE SAME BUS IF NON-ISOLATED. Next I'll contact the company to see if they can make 3x 18-180V -> 13.5V version (for solar in + EUC discharge) Would be better than having to get 3x 800W 105-180V -> 13.5V (for EUC discharge) AND 1x 650W 45-90V -> 13.5V (for solar in) I found the link to the company that makes them, in case you want to buy them cheaper than Aliexpress (you HAVE to specify that you want an isolated unit): https://kellycontroller.com/shop/kl-dcdc/ oh also the 140mm pwm fan will be controlled by a Digital PWM controller module with a temperature probe on the hottest isolated converter, I still need to decide where to went the hot air. Right now the fan is pulling air in. ... Hmm, looking at the rough shape of the 3D mod it looks prime for having some smaller cigs solar panels on the sides and top, allowing me to charge the wheel from sun WHILE driving. I will look into potentially changing dimensions of this 3D mod to accommodate that. Edited February 22 by xiiijojjo Quote Link to comment Share on other sites More sharing options...
xiiijojjo Posted February 23 Author Share Posted February 23 (edited) My most recent design: I removed the cooler. I will be carrying that in/on a backpack, the box was simply too long. removed 2x non-isolated converters and I fit 4x isolated converters in there Switched out the 1x140mm fan for 2x120mm fans which will be temperature controlled. Made a cut-out for plugging AC loads into the inverter (there will be a latch so it can be closed while not in use) I still have to find out where in the bottom to cut out holes or air intake Edited February 23 by xiiijojjo Quote Link to comment Share on other sites More sharing options...
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