Lets say this is my starting system:
https://d31ezp3r8jwmks.cloudfront.net/e63qawtqq2yyqmd6x0i38axlms1a
A connector box w/ multiple MPPTs, batteries in parallel, 48V....
Plan to expand this system with even more MPPTs and battery strings (e.g. plan to have about 35kW of solar, 65kWh of batteries). The current coming from the solar will be too high for each battery string. So, if any imbalance happens, and the current becomes to high for a string, it's BMS will trigger. Likely then other BMSs will trigger.
I would like to have some kind of current limiter on each battery string so that the BMS doesn't trigger due the imbalance. Is there some standard practice when it comes to handling this ? Tried reading on parallel BMSs but didn't get too far. Maybe some kind of current source (PWM?) in each battery string, that limits the current to the batteries spec.
Or maybe nothing is needed; in normal operation, w/ batteries having similar spec, and with BMS in each string, the current imbalance will be too small and will not cause any overload. E.g. 500A into 4 strings, each handing 200A, should allow for quite some imbalance. Thus, I shouldn't expect BMS to trigger on overload unless there is a really a faulty condition, which is ok.
https://d31ezp3r8jwmks.cloudfront.net/e63qawtqq2yyqmd6x0i38axlms1a
A connector box w/ multiple MPPTs, batteries in parallel, 48V....
Plan to expand this system with even more MPPTs and battery strings (e.g. plan to have about 35kW of solar, 65kWh of batteries). The current coming from the solar will be too high for each battery string. So, if any imbalance happens, and the current becomes to high for a string, it's BMS will trigger. Likely then other BMSs will trigger.
I would like to have some kind of current limiter on each battery string so that the BMS doesn't trigger due the imbalance. Is there some standard practice when it comes to handling this ? Tried reading on parallel BMSs but didn't get too far. Maybe some kind of current source (PWM?) in each battery string, that limits the current to the batteries spec.
Or maybe nothing is needed; in normal operation, w/ batteries having similar spec, and with BMS in each string, the current imbalance will be too small and will not cause any overload. E.g. 500A into 4 strings, each handing 200A, should allow for quite some imbalance. Thus, I shouldn't expect BMS to trigger on overload unless there is a really a faulty condition, which is ok.
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