Stack Voltage Calibration - Nuvation Energy NUV300-BC-12 Product Manual

7.9.2.2. Stack Current Field Calibration
Units that have been factory locked may still require tuning for variability in shunts on a per-unit
basis. The equation for Stack Current Field Calibration adjustment is:
The gain is set in the configuration as follows.
stack_power.current_gain (Configuration)
▪
Fine tuning gain for raw current values.
▪
A value of 1000 = +1% adjustment (rawcurrent * 1.01)
▪
A value of -1000 = -1% adjustment (rawcurrent * 0.99).
At the factory, appropriate limits for the gain are defined to ensure a user does not misconfigure the
system. The gain limit is set in the configuration as follows:
stack_power.current_gain_limit (Factory)
▪
Absolute value of the limit for gains on raw current values.
▪
If the stack_power.current_gain register is set to outside of this limit, the gain applied will be
limited to this value.
7.9.2.3. Charge Deadband Setting
In addition to calibrating current readings, it is also necessary to define the deadband that will be
used to determine whether the battery stack is charging, discharging, or at rest (holding).
stack_charge_status.hold_current (Factory)
▪
The battery stack is considered at rest unless the absolute value of current exceeds this
threshold
▪
Set as required by application (typically between 50 and 100 mA)
While this threshold is used to qualify certain aspects of SoC estimation, Coulomb counting takes
place continuously regardless of the configured hold current value. Other functions that require
knowledge of the charge or discharge state of the stack (e.g. the thermistor temperature thresholds)
also make use of this threshold.

7.9.3. Stack Voltage Calibration

Stack voltage measurements are made using a voltage sensing analog front-end (AFE) that must be
configured for Nuvation Energy BMS.
Document ID: NE-PM-002
Nuvation Energy Low-Voltage BMS - Product Manual
126 Rev 1.2, 2021-03-03
Curie Update 1