Battery Module Voltage Balancing With Constant Discharge Current

The patent applies dynamics by making the discharge current adjustable and time-dependent. The control unit dynamically modifies the discharge current magnitude based on real-time voltage measurements and balancing progress, transitioning from static passive balancing to dynamic active balancing. This allows the system to maintain high discharge currents initially for rapid balancing, then reduce currents as voltage equilibrium approaches, thereby achieving voltage equilibrium much faster than traditional passive balancing while controlling total energy consumption.

The patent changes the parameter of discharge current from a fixed, naturally decaying value to a controllable, adjustable parameter. By using PWM control and adjustable current sources, the system can maintain discharge currents at optimal levels throughout the balancing process rather than allowing them to decay to near-zero levels. This parameter change enables the system to achieve voltage equilibrium in significantly reduced time while managing energy consumption through intelligent current profiling.

The patent implements feedback control by continuously monitoring battery module voltages and using this information to adjust discharge currents in real-time. The control unit receives voltage measurements from sensor units, compares actual voltages to target values, and dynamically modifies discharge current magnitudes based on the voltage differences and balancing progress. This feedback mechanism allows the system to maintain high discharge currents when voltage differences are large (fast balancing) and reduce currents as equilibrium approaches (energy efficiency), achieving both fast balancing and controlled energy consumption simultaneously.

The patent employs periodic action through PWM (pulse width modulation) control of the discharge currents. Instead of using continuous analog current adjustment, the system applies periodic pulsed currents with varying duty cycles to achieve effective average current control. This periodic approach enables precise control of energy delivery while maintaining high instantaneous currents for rapid balancing, resolving the contradiction between balancing speed and energy consumption.

The patent applies universality by designing a modular control architecture where a single control unit performs multiple functions: voltage measurement, current regulation, PWM generation, and balancing algorithm execution for all battery modules. Instead of implementing separate control circuits for each module, the system uses one multi-functional control unit that can independently manage multiple modules through software control and PWM signals. This universal approach achieves individual module control precision while minimizing hardware complexity through functional integration.

The patent merges multiple control functions into a unified control system. The control unit combines voltage sensing, current regulation, PWM signal generation, and balancing logic into a single integrated device. By merging these functions that could have been implemented as separate components for each battery module, the system achieves individual module control precision while significantly reducing overall device complexity. The modular software architecture within the unified control unit allows independent management of each module without requiring separate hardware control circuits.