Architecture & Functional Components Flashcards
7 cards from real BMS practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Architecture & Functional Components flashcards as text
In a modular BMS architecture, what does a 'module controller' manage?
Answer: A single battery module consisting of several cell groups
A module controller oversees the cells within one physical battery module, reporting aggregated data to the pack-level master BMS.
Which BMS hardware component provides galvanic isolation between the high-voltage bus and the low-voltage measurement circuitry?
Answer: Isolation amplifier or optocoupler
Isolation amplifiers or optocouplers transfer analog or digital signals across a voltage barrier without a direct electrical connection.
What is the role of the 'service disconnect' in a high-voltage BMS architecture?
Answer: Provides a manual means to interrupt the high-voltage circuit for safe service
The service disconnect (often a plug or lever) lets technicians manually break the high-voltage circuit before performing maintenance, preventing shock hazards.
A BMS firmware uses a Coulomb-counting algorithm. What happens to SOC accuracy if the current sensor has a fixed offset error?
Answer: SOC error accumulates over time, drifting further from the true value
Coulomb counting integrates current over time, so any constant sensor offset is also integrated, causing SOC drift that worsens with each charge/discharge cycle.
Which active balancing technique transfers charge between cells using a shared inductor?
Answer: Inductive (flyback) balancing
Inductive (flyback or buck-boost) balancers temporarily store energy in an inductor and transfer it to a lower-voltage cell, preserving energy rather than wasting it.
In a BMS protection hierarchy, which layer typically acts fastest to prevent over-current damage?
Answer: Hardware comparator or dedicated protection IC
Hardware comparators or dedicated protection ICs trigger in microseconds, far faster than software loops, making them the first line of defense against over-current.
What is the purpose of the 'cell voltage reference' circuit on a BMS slave board?
Answer: To provide a stable voltage against which cell measurements are compared for ADC accuracy
A precision voltage reference ensures the ADC's full-scale input is accurate, so cell voltage measurements are not skewed by supply rail variations.