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Examples of critical operating states
The following examples shows critical operating states who can occur due to regulator priorities. The
examples refer to schematic diagram below.
Operating mode of the devices:
BDC: Boostmode, UHS_COM active
[SG_Sollwert]
Condition
ULS > ULS_MAX
BDC regulates ULS_MAX by converting energy from LS to HS.
ILS_MAX or IHS_MAX is active.
UHS rises till UHS = UHS_MAX.
UHS_MAX is active, because of the higher priority of the HS-limit-regulators.
BDC changes the operating mode to buckmode by converting energy from HS to LS.
ILS_MIN or IHS_MIN is active.
UHS falls till UHS < UHS_MAX or ULS overvoltage detection (ULS > 600V) is active.
Inadvertent operating-mode-changes from boost- to buckmode can be avoided by setting ILS_MIN
and/or IHS_MIN to zero.
(See chapter “Recommended BDC operating settings”)
Condition
ULS < ULS_MIN
BDC regulates ULS_MIN by converting energy from HS to LS.
BDC changes the operating mode to buckmode.
ILS_MIN or IHS_MIN is active.
UHS falls.
ULS rises till ULS > ULS_MIN or UHS < UHS_MIN.
Inadvertent operating-mode-changes from boost- to buckmode can be avoided by setting ILS_MIN
and/or IHS_MIN to zero. (S
ee chapter “Recommended BDC operating settings”)
ULS_MAX [SG_ULS_max]
BDC546
UHS_COM active
ILS_MIN [SG_ILS_min]
Battery 1
Battery 2
UHS_COM [SG_Sollwert]
UHS_MAX [SG_UHS_max]
IHS_MAX [SG_IHS_max]
IHS_MIN [SG_IHS_min]
ILS_MAX [SG_ILS_max]
Low-Side (LS)
High-Side (HS)
UHS_MIN [SG_UHS_min]
ULS_MIN [SG_ULS_min]
ULS
UHS
