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Changes for page 3.4 Battery parameters

Last modified by Admin on 2025/04/09 12:04
From version 8.2
edited by Admin
on 2024/11/21 16:48
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To version 9.2
edited by Admin
on 2024/11/21 16:54
Change comment: There is no comment for this version

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... ... @@ -178,8 +178,73 @@
178 178  
179 179  [[Cell analysis section>>image:1732207696322-587.png||data-xwiki-image-style-alignment="center" height="213" width="258"]]
180 180  
181 -== SOC correction ==
181 +In this section:
182 182  
183 +* Enable – a flag to enable cell analysis;
184 +* Discharge step, Ah;
185 +* Delta voltage – a maximum allowable voltage drop for the cell, V;
186 +* Logic index – an address of the BMS Logic board to which the analyzed cell is connected;
187 +* Cell index – a position of the analyzed cell connected to the BMS Logic board;
188 +* Analyse cell with minimum voltage – a flag to analyse of the least charged cell (in this case, the values of Logic index and Cell index are ignored).
189 +
190 +Discharge step should be set equal to
191 +
192 +Discharge step = С/21,
193 +
194 +where C is the cell capacity.
195 +
196 +The discharge characteristic will be constructed for the given cell (its position is determined by the fields Logic index and Cell index).
197 +
198 +The algorithm for determining the discharge characteristic of the battery will be started if the Enable flag is set. From this moment, the control of the discharge relay is performed by this algorithm.
199 +
200 +Algorithm steps:
201 +
202 +1. DOD = 0.
203 +1. Disconnecting the discharge relay.
204 +1. Waiting for the relaxation of the battery.
205 +1. Measuring Uocv = U.
206 +1. Saving the point of the discharge characteristic (Q, U,,OCV,,).
207 +1. Activation of the discharge relay. DOD,,1,, = DOD + Discharge step, U,,1,, = U
208 +1. If DOD = DOD,,1,, or U < (U,,1,, – Delta voltage), then go to step 2.
209 +1. If the "Undervoltage" error is detected, then the end of the algorithm.
210 +
211 +During the operation of the algorithm, a file with the name "CELLANALYSIS.TXT" in the CSV format will be created on the SD card.
212 +
213 +File structure:
214 +
215 +|**Time**|**DOD**|**Logic**|**Cell**|**OCV**|**Resistance**
216 +|**10.11.2017 12:28:34**|0.0|1|1|4.180|0.080000
217 +|**...**|...|…|…|...|...
218 +
219 +Parameter names:
220 +
221 +* Time – date and time;
222 +* DOD – depth of discharge, Ah;
223 +* Logic – the address of the BMS Logic board to which the analyzed cell is connected;
224 +* Cell – position of the analyzed cell for which OCV and Resistance values are provided;
225 +* OCV – cell voltage Uocv, V;
226 +* Resistance – cell resistance, Ohm.
227 +
228 +== 3.4.7 Charge current map ==
229 +
230 +The BMS Main 2.x board calculates maximum allowable charge current values in respect to SOC and battery temperature, contactor temperature and maximum cell voltage.
231 +
232 +Calculated currents values are sending to chargers or intellectual loads over the CAN bus.
233 +
234 +To configure parameters for determining the charge current limit, select the menu "Cells → Charge current map":
235 +
236 +[[Charge current map settings>>image:1732208033738-498.png||data-xwiki-image-style-alignment="center" height="655" width="453"]]
237 +
238 +== 3.4.8 Discharge current map ==
239 +
240 +The BMS Main 2.x board calculates maximum allowable discharge current values in respect to SOC and battery temperature, contactor temperature and maximum cell voltage.
241 +
242 +Calculated currents values are sending to chargers or intellectual loads over the CAN bus.
243 +
244 +To configure parameters for determining the charge current limit, select the menu "Cells → Charge current map":
245 +
246 +== 3.4.9 SOC correction ==
247 +
183 183  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)).
184 184  
185 185  To configure parameters for periodically correcting the battery state of charge, select the menu "Cells → SOC correction":
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