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How do these boosters work?
- Thread starter Cyclomania
- Start date
lnanek
1 kW
- Joined
- Sep 26, 2022
- Messages
- 477
I tried one once to go from 48V to 52V in hopes of higher top speed, but my controller kept throwing faults. Maybe you need to disable any regen, provided your controller supports that, to avoid. Some controllers seem to depend on having a direct connection to the battery they can pump current back into in situations like downhill with the wheel moving faster than the motor can normally drive it.
beemac
10 kW
The higher the voltage difference generally the poorer the efficiency. You also need to watch out that your battery can cope, as say 72v@20A would need 30A@48V (at perfect efficiency) and as the soc drops the current the battery needs to provide increases.
I've tried cheap 1500W dcdc converters to run my tsdz2 at a constant 60V. It's was good to have a bit of extra speed and no slowdown as soc reduced but in the end wasn't worth the faff and extra things mounted on my bike..
1200W 20A/1500W 30A/1800W 40A DC Converter Boost Step-up Power Supply Module New | eBay
Output power: 1800W. Enter 36V 20A = 720W, input 48V 20A = 960W, input 60V 20A = 1200W. 1 x 1500W 30A boost constant current module. Module properties: non-isolated step-up module (BOOST). Input current: 40A.
www.ebay.co.uk
docw009
1 MW
Your link is for a battery blender and I don't see its use here, but I figure you are asking about DC-DC boost converters. I had this commonly available model I used one to boost my 36V battery to 50V.
At that level, it seemed to run OK. You get a constant DC level, so the speed didn't drop as the battery ran down. The tradeoff is poor efficiency. I wrote a post here about it several years ago, but cannot find it. This is from memory, so it could be wrong. To get 10A output at 50V, I was pulling around 20A from my 36V battery, I had wattmeters on both sides of the converter to check that. That's a lot of power being wasted.
I eventually cranked it up to 60V. Bike was pretty fast, but it was too much. I blew the battery fuse, had to ride home w/o power, and lost interest, A few weeks later, the battery went unbalanced. A cell had failed. It could have been the age of the battery or it could have been high stress. Who knows.
At that level, it seemed to run OK. You get a constant DC level, so the speed didn't drop as the battery ran down. The tradeoff is poor efficiency. I wrote a post here about it several years ago, but cannot find it. This is from memory, so it could be wrong. To get 10A output at 50V, I was pulling around 20A from my 36V battery, I had wattmeters on both sides of the converter to check that. That's a lot of power being wasted.
I eventually cranked it up to 60V. Bike was pretty fast, but it was too much. I blew the battery fuse, had to ride home w/o power, and lost interest, A few weeks later, the battery went unbalanced. A cell had failed. It could have been the age of the battery or it could have been high stress. Who knows.
Every time you perform a conversion of power, you lose power.
it would be a lot better to just use flux weakening/phase advance on your controller to get additional speed. The efficiency loss is going to be lower than using a standalone DC-DC device.
it would be a lot better to just use flux weakening/phase advance on your controller to get additional speed. The efficiency loss is going to be lower than using a standalone DC-DC device.