I want to design BMS by using AD8450 and AD1972, 64 pcs of batteries connect to same input source, and battery charge independently,
AD1972 have energy recycle feature, so the energy on battery can discharge back to input bus. can 64 pcs battery discharge to the input bus at the same time? maybe i need to replace the ESS on input bus for preventing input voltage rising, i just thinking the current balancing problem when 64pcs battery discharge at the same time
I'm not an expert on mass battery conversion in a production environment (initial charging/forming). However I can relate a few observations from various travels. Forgive me if I tell you something you already know .
You'll need a PID loop for each battery, that is to say, an AD8450 and ADP1972 (or the soon to arrive, ADP1974), and an ac-dc power supply. Both the AD8450 and the ADP1972 feature recycling of power. This is still a rather new technique, but our understanding is that the power is metered back too the grid using dc-ac conversion.
The AD8450 features a bus pin called CSH, or current share, which provides a measure of the highest measured current of each battery in the array. For an explanation of the current share and maximum current pins see pages 27 and 28 of the data sheet (attached). If one uses the uncommitted op-amp as described in the text, the assumption is that the error signal output OAVO is usable as a signal source to amend the charge current for each of the boards. Furthermore, the assumption is that the same ISET is applied to each channel from a common source.
Is this an academic project, or a commercial application? We get lots of questions from both milieus.
I hope this helps,
Does anyone know if there is any Evaluation Board that has AD8541 + AD1972 on board?
There is not an evaluation board containing both the AD8451 and ADP1972.
There is an AD8450/ADP1972 Battery Testing and Formation Evaluation Board that may be made available for evaluation by contacting your local Analog Devices Sales Office. An informative User's Guide can be found at Battery Testing and Formation | Analog Devices .