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Wiki source code of 3.4 Protections

Version 18.1 by Admin on 2025/04/04 12:00
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1 (% data-numbered-headings-start="3" style="--numbered-headings-start: 2;font-size: 0px;color: rgba(0, 0, 0, 0.0);margin-bottom: 0px; margin-top: 0px;" %)
2 = Settings =
3
4 (% data-numbered-headings-start="4" style="--numbered-headings-start: 3;font-size: 0px;color: rgba(0, 0, 0, 0.0);margin-bottom: 0px; margin-top: 0px;" %)
5 == Protections ==
6
7 The BMS Main X monitors the battery modules, compares the voltages and currents of the modules, and protects the battery system from damage.
8
9 (% class="box errormessage" %)
10 (((
11 **Attention!**
12 Behavior of contactors at different errors is configured in **corresponding contactor settings**!
13 )))
14
15 === Charging current limit ===
16
17 The BMS Main X device protects the battery from charging current higher than estimated current limit.
18
19 To configure parameters of the charge current limit, select the "Protections → Charge current limit" section:
20
21 [[image:1740754371437-635.png||data-xwiki-image-style-alignment="center" data-xwiki-image-style-border="true" height="142" width="800"]]
22
23 In this section:
24
25 * Enable – a flag to enable the protection;
26 * Threshold to switch from Region 1 to Region 2 – a threshold current value, dividing regions 1 and 2 with their error generation conditions, A;
27 * Region 1: Current difference – an absolute difference of measured battery current and calculated value “Charge current limit”, at which error is generated (condition for Region 1), A;
28 * Region 2: Current difference – a relative difference of measured battery current and calculated value “Charge current limit”, at which error is generated (conditions for Region 2), %;
29 * Delay before setting the error, millisecond;
30 * Delay before clearing the error, second;
31 * Lock – a flag to block the error until the device is restarted.
32
33 As a result of the operation of the charging current limit protection, the “Current limit error (CH)” is generated.
34
35 Error generation conditions:
36
37 * if the current is positive, less than “Threshold to switch from Region 1 to Region 2” value and exceeds “Charge current limit” by the “Region 1: Current difference” value during the “Delay before setting the error” time;
38 * if the current is positive, more than “Threshold to switch from Region 1 to Region 2” value and exceeds “Charge current limit” by the (“Region 2: Current difference” × “Charge current limit”) / 100 value during the “Delay before setting the error” time.
39
40 Error is cleared if conditions for generating an error do not apply during the “Delay before clearing the error” time.
41
42 === Discharging current limit ===
43
44 The BMS Main X device protects the battery from discharging current higher than estimated current limit.
45
46 To configure parameters of the charge current limit, select the "Protections → Discharge current limit " section:
47
48 [[image:1740754420820-767.png||data-xwiki-image-style-alignment="center" data-xwiki-image-style-border="true" height="138" width="800"]]
49
50 In this section:
51
52 * Enable – a flag to enable the protection;
53 * Threshold to switch from Region 1 to Region 2 – a threshold current value, dividing regions 1 and 2 with their error generation conditions, A;
54 * Region 1: Current difference – an absolute difference of measured battery current and calculated value “Discharge current limit”, at which error is generated (condition for Region 1), A;
55 * Region 2: Current difference – a relative difference of measured battery current and calculated value “Discharge current limit”, at which error is generated (conditions for Region 2), %;
56 * Delay before setting the error, millisecond;
57 * Delay before clearing the error, second;
58 * Lock – a flag to block the error until the device is restarted.
59
60 As a result of the operation of the charging current limit protection, the “Current limit error (DCH)” is generated.
61
62 Error generation conditions:
63
64 * if the current is negative, and the current modulus is less than “Threshold to switch from Region 1 to Region 2” value and exceeds “Discharge current limit” by the “Region 1: Current difference” value during the “Delay before setting the error” time;
65 * if the current is negative, and the current modulus is more than “Threshold to switch from Region 1 to Region 2” value and exceeds “Discharge current limit” by the (“Region 2: Current difference” × “Discharge current limit”) / 100 value during the “Delay before setting the error” time.
66
67 Error is cleared if conditions for generating an error do not apply during the “Delay before clearing the error” time.
68
69 === Battery cover ===
70
71 The BMS Main X device detects the opening of the battery cover and performs a protective opening of the contactors.
72
73 Battery cover protection is configured in the "Protections - Battery cover" section:
74
75 [[image:1734356776691-451.png||data-xwiki-image-style-alignment="center" data-xwiki-image-style-border="true" height="88" width="800"]]
76
77 In this section:
78
79 * Enable – a flag to enable the protection;
80 * Delay before setting the error;
81 * Delay before clearing the error;
82 * Lock – a flag to block the error until the device is restarted.
83
84 As a result of the protection against opening the battery cover, the “Battery cover” error is generated. Conditions for generating the error:
85
86 * presence of the “Battery cover” signal during the “Delay before setting the error” time.
87
88 Conditions for clearing the error:
89
90 * no “Battery cover” signal during the “Delay before clearing the error” time.
91
92 (% class="box warningmessage" %)
93 (((
94 If there is the "Battery cover" error, the **"Critical error flag" is generated.**
95 )))
96
97 === Insulation ===
98
99 The BMS Main X device detects a signal from an external insulation monitoring device (e.g., Bender IR155) and performs a protective opening of the contactors.
100
101 Insulation protection is configured in the "Protections - Insulation" section:
102
103 [[image:1740754491323-815.png||data-xwiki-image-style-alignment="center" data-xwiki-image-style-border="true" height="121" width="800"]]
104
105 In this section:
106
107 * Enable – a flag to enable the protection;
108 * Checking algorithm – isolation checking mode:
109 ** Always on – check is always performed;
110 ** On charging – check is performed only if the “Charge request” is set;
111 ** Except charging - check is performed only if the “Charge request” is cleared;
112 * Delay before setting the error, second;
113 * Delay before clearing the error, second;
114 * Lock – a flag to block the error until the device is restarted.
115
116 The “Insulation fault” is set if the “Insulation status” signal is detected during the “Delay before setting the error” time. The “Insulation status” signal can be received through the discrete input or by the CAN bus from an insulation monitoring device. The “Insulation fault” is cleared if the “Insulation status” signal is cleared during the “Delay before clearing the error” time.
117
118 (% class="box warningmessage" %)
119 (((
120 If there is the "Insulation fault" error, **the critical error flag is generated.**
121 )))
122
123 === Contactor feedback ===
124
125 The BMS Main X device detects the feedback signals from the main contactors and, in the event of a discrepancy between the feedback signals from the control signals, performs a protective opening of the contactors.
126
127 Contactor feedback protection is configured in the “Protections – Contactor feedback” section:
128
129 [[image:1734356776695-557.png||data-xwiki-image-style-alignment="center" data-xwiki-image-style-border="true" height="89" width="800"]]
130
131 In this section:
132
133 * Enable – a flag to enable the protection;
134 * Delay before setting the error;
135 * Delay before clearing the error;
136 * Lock – a flag to block the error until the device is restarted.
137
138 As a result of the protection against contactor failures, the errors "CH contactor feedback error", "DCH contactor feedback error", "CH/DCH contactor feedback error" are generated. Conditions for generating the errors:
139
140 * feedback signal from the contactor differs from the contactor control signal for the time "Delay before setting the error".
141
142 Conditions for clearing the error:
143
144 * feedback signal from the contactor repeats the contactor control signal for the time "Delay before clearing the error".
145
146 (% class="box warningmessage" %)
147 (((
148 If there is the “CH contactor feedback error”, “DCH contactor feedback error”, or “CH/DCH contactor feedback error”, **the critical error flag is generated.**
149 )))
150
151 === Module offline ===
152
153 The BMS Main X device detects the loss of communication with the battery modules and performs a protective opening of the contactors.
154
155 Protection against loss of communication with battery modules is configured in the "Protections - Module offline" section:
156
157 [[image:1740754588971-137.png||data-xwiki-image-style-alignment="center" data-xwiki-image-style-border="true" height="118" width="800"]]
158
159 In this section:
160
161 * Enable – a flag to enable the protection;
162 * Number of offline modules to set the error;
163 * Delay before setting the error, second;
164 * Delay before clearing the error, second;
165 * Lock – lock the error until the device is reset.
166
167 As a result of the protection from loss of communication with battery modules, the "Module offline" error is generated.
168
169 Error generation conditions:
170
171 * more than “Number of offline modules to set the error” battery modules do not respond to the commands of the BMS Main X device within “Delay before setting the error” time.
172
173 Conditions for removing the error:
174
175 * less than “Number of offline modules to set the error” battery modules do not respond to the commands of the BMS Main X device within “Delay before clearing the error” time.
176
177 (% class="box warningmessage" %)
178 (((
179 If there is the "Module offline" error, **“Critical error” is generated.**
180 )))
181
182 === Voltage unbalance (in any state) ===
183
184 Before closing the contactors for charging and discharging battery modules, the BMS Main X device detects those modules whose voltage is significantly different from the rest. For unbalanced modules, errors "Voltage unbalance (CH)" (charge circuit) and "Voltage unbalance (DCH)" (discharge circuit) are generated.
185
186 Protection against voltage unbalance of battery modules is configured in the section "Protections - Voltage unbalance (in any state)":
187
188 [[image:1740754732291-420.png||data-xwiki-image-style-alignment="center" data-xwiki-image-style-border="true" height="127" width="800"]]
189
190 In this section:
191
192 * Enable – a flag to enable the protection;
193 * Delta voltage – maximum allowable voltage difference of battery modules, V;
194 * Use the open circuit voltage to detect the error – a flag to enable U,,ocv,, correction;
195 * Delay before setting the error;
196 * Delay before clearing the error;
197 * Set the 'Voltage unbalance' error for the modules that are not ready to charge/discharge;
198 * Lock – a flag to block the error until the device is restarted.
199
200 As a result of the operation of the voltage unbalance protection the errors “Voltage unbalance (CH)” and “Voltage unbalance (DCH)” are generated.
201
202 Conditions for generating the error:
203
204 * battery module is not included in the largest group of modules whose voltages differ from each other by no more than "Delta voltage" during the "Delay before setting the error" time;
205 * module is not ready to charge or discharge;
206
207 Conditions for clearing the error:
208
209 * battery module is in the largest group of balanced modules during the "Delay before clearing the error" time;
210 * module is ready to charge or discharge.
211
212 (% class="box infomessage" %)
213 (((
214 If there is the “Voltage unbalance (CH)” or "Voltage unbalance (DCH)" error, **corresponding battery module do not close its contactors while joining  to charge of discharge**.
215 )))
216
217 === Current unbalance (in “Balancing” state) ===
218
219 When battery modules are connected in parallel, the most charged modules transfer charge to the least charged modules. The process of charge transfer is accompanied by the flow of balancing currents. The BMS Main X device detects modules with high balancing currents and generates “Current unbalance (CH)” (charge circuit) and “Current unbalance (DCH)” (discharge circuit) errors for them.
220
221 Protection against current unbalance of battery modules is configured in the section "Protections - Current unbalance":
222
223 [[image:Battery management systems.BMS Main 3X.3\. Configuration.3\.4 Protections.WebHome@1734090244843-403.png||data-xwiki-image-style-alignment="center" data-xwiki-image-style-border="true" height="116" width="800"]]
224
225 In this section:
226
227 * Enable – a flag to enable the protection;
228 * Maximum current – a maximum allowable self-balancing current of battery modules, A;
229 * Delay before setting the error;
230 * Delay before clearing the error;
231 * Check all the time (not only in the ‘Balancing’ state) – a flag to enable voltage check not only in “Balancing” state;
232 * Lock – a flag to block the error until the device is restarted.
233
234 As a result of the operation of the current unbalance protection the errors “Current unbalance (CH)” and “Current unbalance (DCH)” are generated.
235
236 Conditions for generating the error:
237
238 * the current of the battery module is greater than the "Maximum current" value during the "Delay before setting the error" time.
239
240 Conditions for clearing the error:
241
242 * the current of the battery module is less than the "Maximum current" value during the "Delay before clearing the error" time.
243
244 (% class="box infomessage" %)
245 (((
246 If there is the “Current unbalance (CH)” or "Current unbalance (DCH)" error, **corresponding battery module opens its charging or discharging contactor**.
247 )))
248
249 === Charging current unbalance (in “Charging” state) ===
250
251 During battery charging, the currents of the battery modules may vary. The BMS Main X device detects modules whose charging currents are significantly different from the currents of other modules and generates the “Charging current unbalance” errors for them.
252
253 Protection against different charge currents is configured in the "Protections – Charging current unbalance" section:
254
255 [[image:1734356802715-364.png||data-xwiki-image-style-alignment="center" data-xwiki-image-style-border="true" height="75" width="600"]]
256
257 In this section:
258
259 * Enable – a flag to enable the protection;
260 * Delta current – maximum allowable charge current difference, A;
261 * Delay before setting the error;
262 * Delay before clearing the error;
263 * Lock – a flag to block the error until the device is restarted.
264
265 As a result of the operation of the protection the “Charging current unbalance” are generated.
266
267 Conditions for generating the errors:
268
269 * battery module is not included in the largest group of modules whose charge currents differ from each other by no more than "Delta current" during the "Delay before setting the error" time.
270
271 Conditions for clearing the error:
272
273 * battery module is included in the largest group of modules with similar charge currents during the “Delay before clearing the error” time.
274
275 (% class="box infomessage" %)
276 (((
277 If there is the “Charging current unbalance” error, **corresponding battery module opens its charging contactor**.
278 )))
279
280 === Discharging current unbalance (in “Discharging” state) ===
281
282 During battery discharging, the currents of the battery modules may vary. The BMS Main X device detects modules whose discharging currents are significantly different from the currents of other modules and generates the “Discharging current unbalance” errors for them.
283
284 Protection against different discharge currents is configured in the "Protections – Discharging current unbalance" section:
285
286 [[image:1734356802717-812.png||data-xwiki-image-style-alignment="center" data-xwiki-image-style-border="true" height="75" width="600"]]
287
288 In this section:
289
290 * Enable – a flag to enable the protection;
291 * Delta current – maximum allowable discharge current difference, A;
292 * Delay before setting the error;
293 * Delay before clearing the error;
294 * Lock – a flag to block the error until the device is restarted.
295
296 As a result of the operation of the protection the “Discharging current unbalance” are generated.
297
298 Conditions for generating the errors:
299
300 * battery module is not included in the largest group of modules whose discharge currents differ from each other by no more than "Delta current" during the "Delay before setting the error" time.
301
302 Conditions for clearing the error:
303
304 * battery module is included in the largest group of modules with similar discharge currents during the “Delay before clearing the error” time.
305
306 (% class="box infomessage" %)
307 (((
308 If there is the “Discharging current unbalance” error, **corresponding battery module opens its discharging contactor**.
309 )))
310
311 === High contactor temperature ===
312
313 The BMS Main X device protects power contactors from overheating. To measure the temperature of the contactor, one of the thermistors connected to the X5 connector is used.
314
315 To change the overheating protection parameters of power contactors, select the "Protections → High contactor temperature" section:
316
317 [[image:1740756362809-292.png||data-xwiki-image-style-alignment="center" data-xwiki-image-style-border="true" height="161" width="800"]]
318
319 In this section:
320
321 * Enable – a flag to enable the protection;
322 * Thermistor – a selection of which cell thermistor will be used as contactor temperature sensor;
323 * Maximum contactor temperature, °C;
324 * Tolerant contactor temperature, °C;
325 * Delay before setting the error, second;
326 * Delay before clearing the error, second;
327 * Lock – a flag to block the error until the device is restarted.
328
329 If there is a contactor overheat, the "High contactor temperature" error is generated.
330
331 Error generation conditions:
332
333 * the contactor temperature is greater than the “Maximum contactor temperature” value during the “Delay before setting the error” time.
334
335 Conditions for removing the error:
336
337 * the contactor temperature is lower than the “Tolerant contactor temperature” value during the “Delay before clearing the error” time.
338
339 === WDT reset ===
340
341 If the BMS firmware hangs, the watchdog timer resets the device. The BMS can detect that the device was reset and generates the “WDT reset” error.
342
343 To change the parameters of the watchdog protection, select the "Protections → WDT reset" section:
344
345 [[image:Battery management systems.BMS Main 3X.3\. Configuration.3\.4 Protections.WebHome@1734090244845-157.png||data-xwiki-image-style-alignment="center" data-xwiki-image-style-border="true" height="93" width="800"]]
346
347 In this section:
348
349 * Enable – a flag to enable the protection;
350 * Delay before clearing the error, second;
351 * Lock – a flag to block the error until the device is restarted.
352
353 Conditions for removing the error:
354
355 * the “Delay before clearing the error” time has passed from the device startup.
356
357 (% class="box warningmessage" %)
358 (((
359 If there is the "WDT reset" error, **“Critical error” is generated.**
360 )))
361
362 === Critical error ===
363
364 Some of the errors are system critical. A separate signal named "Critical error" indicates a BMS fault.
365
366 To change the critical error parameters, select the "Protections → Critical error" section:
367
368 [[image:1740756532131-419.png||data-xwiki-image-style-alignment="center" data-xwiki-image-style-border="true" height="118" width="800"]]
369
370 In this section:
371
372 * Enable – a flag to enable the protection;
373 * Delay before setting the error;
374 * Delay before clearing the error;
375 * Lock – a flag to block the error until the device is restarted.
376
377 The "Critical error" signal is generated if at least one of the critical errors (see [[Errors>>doc:Battery management systems.Additional information.2\. Strings controllers\: signals and errors.WebHome||anchor="HErrors"]]) is generated during the “Delay before setting the error” time.
378
379 The “Critical error" signal is cleared if there are no errors from the list above during the “Delay before clearing the error” time.