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Changes for page 3.4 Battery parameters

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... ... @@ -136,8 +136,36 @@
136 136  * Start cell discharging – a command to start forced balancing of all battery cells (used for service purposes);
137 137  * Stop cell discharging – a command to stop forced balancing of all battery cells (used for service purposes).
138 138  
139 -== 3.4.5 Series balancing ==
139 +== 3.4.5 Series balancing ==
140 140  
141 +The BMS Main 2.x board supports work with two independent (galvanically unrelated) cell series. To monitor the status of two series, two current sensors are used: primary and secondary (AUX). A series of cells must be equivalent: they must have the same number of cells and the same capacity.
142 +
143 +Since the series of cells can operate at different loads, they must be balanced. For this, the BMS Main 2.x provides two relays: “Balancing series 1” and “Balancing series 2” (see section Configuration of output discrete signals and relays), as well as a combined algorithm that considers both the voltage of each series and the charge that these series gave load. “Balancing series 1” and “Balancing series 2” relays are used to connect high-power balancing resistors in parallel with cells series 1 and 2.
144 +
145 +When charging the battery, balancing is performed based on the voltage of the series. A balancing resistor is connected to the cell series if:
146 +
147 +* the series voltage is higher than the starting voltage of the balancing;
148 +* the difference between the voltage of a series of cells and the minimum voltage among the battery series is greater than the balancing threshold.
149 +
150 +When the battery is discharging (work on load), balancing is turned on if one of the series gives the load a charge (Ah), which is more by the amount Qthr of the charge given off by another series.
151 +
152 +To change the series balancing parameters, select the menu "Cell → Series balancing":
153 +
154 +[[Series balancing settings>>image:1732207584941-447.png||data-xwiki-image-style-alignment="center" height="258" width="438"]]
155 +
156 +In this section:
157 +
158 +* Enable – a flag to enable series balancing;
159 +* Number of BMS Logic boards in a series;
160 +* Minimum series voltage to start balancing, V;
161 +* Balancing threshold, V;
162 +* Coulomb threshold – the difference of the charges Qthr, given by a series of cells, above which balancing to be started, Ah;
163 +* Period – period to reset of charge counters for each series (to avoid accumulation of error), second.
164 +
165 +== ==
166 +
167 +== ==
168 +
141 141  == SOC correction ==
142 142  
143 143  The BMS Main 2.x board can recalculate the battery SOC after long-term storage or after long-term working in the case when the battery was not charged fully or discharged totally. Recalculation is done based on the tabular dependency Uocv = Uocv (SOC, t) (see section Calculating the state of charge (SOC)).